[PATCH 0/10] x86: EHCI and earlyprintk= improvements

[PATCH 0/10] x86: EHCI and earlyprintk= improvements

[Jason Wessel]

This patch series against the 2.6.31-rc3 covers improving the
reliability of earlyprintk when using a usb debug device connected to
an EHCI debug controller.

The only patch that is not directly related to the USB earlyprintk is
the 5th in the series which changes the console registration such that
you can have more than one earlyprintk device.  It is plausible to
drop this patch if folks object to the idea or implementation.

These patches were heavily test on 12 different systems with a total
of 7 different EHCI controllers on both the x86_64 and i386
architectures.

The series starts by moving the EHCI debug code out of the
arch/x86/kernel/early_printk.c and over to under the
drivers/usb/early/ehci-dbgp.c.  It is plausible to use this code on
other architectures beyond x86.  This also allows the earlyprintk.c to
stay a bit cleaner, since it is primarily intended to handle the
"earlyprintk=" setup.

The other key changes are:
   * Update the documentation to reflect the usage constraints
   * The earlyprintk=keep,... works correctly with dbgp
   * Make the cr nl handling for dbgp the same as the uart drivers
   * Numerous errata and initialization fixes to make the usb
     debug device work with a wide range of EHCI controllers

Thanks,
Jason.

The following changes since commit 78af08d90b8f745044b1274430bc4bc6b2b27aca:
  Linus Torvalds (1):
        Merge branch 'drm-fixes' of git://git.kernel.org/.../airlied/drm-2.6

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.git for_gregkh_2

Jason Wessel (10):
      ehci early_printk: split ehci debug driver from early_printk.c
      usb,early_printk: insert cr prior to nl as needed
      ehci-dbgp: Execute early BIOS hand off
      usb,early_printk: EHCI debug controller initialization delays
      printk,early_printk,console: Allow more than one early console
      ehci-dbgp: stability improvements and external re-init
      ehci-dbgp,ehci: Allow early or late use of the dbgp device
      ehci-dbgp: errata for EHCI debug controller initialization
      ehci-dbgp: errata for EHCI debug/host controller synchronization
      ehci-dbgp,documentation: Documentation updates for ehci-dbgp


 Documentation/kernel-parameters.txt |    2 +-
 Documentation/x86/earlyprintk.txt   |   39 ++-
 arch/x86/kernel/early_printk.c      |  780 ++--------------------------
 drivers/usb/Makefile                |    1 +
 drivers/usb/early/Makefile          |    5 +
 drivers/usb/early/ehci-dbgp.c       |  996 +++++++++++++++++++++++++++++++++++
 drivers/usb/host/ehci-hcd.c         |   33 ++-
 drivers/usb/host/ehci-hub.c         |   10 +
 drivers/usb/host/ehci-pci.c         |   20 -
 include/linux/usb/ehci_def.h        |   13 +
 kernel/printk.c                     |   41 +-
 11 files changed, 1154 insertions(+), 786 deletions(-)
 create mode 100644 drivers/usb/early/Makefile
 create mode 100644 drivers/usb/early/ehci-dbgp.c

[PATCH 01/10] ehci early_printk: split ehci debug driver from early_printk.c

[Jason Wessel]

Move the dbgp early printk driver in advance of refactoring and adding
new code, so the changes to this code are tracked separately from the
move of the code.

The drivers/usb/early directory will be the location of the current
and future early usb code for driving usb devices prior initializing
the standard interrupt driven USB drivers.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/x86/kernel/early_printk.c |  715 ---------------------------------------
 drivers/usb/Makefile           |    1 +
 drivers/usb/early/Makefile     |    5 +
 drivers/usb/early/ehci-dbgp.c  |  723 ++++++++++++++++++++++++++++++++++++++++
 include/linux/usb/ehci_def.h   |    6 +
 5 files changed, 735 insertions(+), 715 deletions(-)
 create mode 100644 drivers/usb/early/Makefile
 create mode 100644 drivers/usb/early/ehci-dbgp.c

diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index 335f049..519a5e1 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -160,721 +160,6 @@ static struct console early_serial_console = {
 	.index =	-1,
 };
 
-#ifdef CONFIG_EARLY_PRINTK_DBGP
-
-static struct ehci_caps __iomem *ehci_caps;
-static struct ehci_regs __iomem *ehci_regs;
-static struct ehci_dbg_port __iomem *ehci_debug;
-static unsigned int dbgp_endpoint_out;
-
-struct ehci_dev {
-	u32 bus;
-	u32 slot;
-	u32 func;
-};
-
-static struct ehci_dev ehci_dev;
-
-#define USB_DEBUG_DEVNUM 127
-
-#define DBGP_DATA_TOGGLE	0x8800
-
-static inline u32 dbgp_pid_update(u32 x, u32 tok)
-{
-	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
-}
-
-static inline u32 dbgp_len_update(u32 x, u32 len)
-{
-	return (x & ~0x0f) | (len & 0x0f);
-}
-
-/*
- * USB Packet IDs (PIDs)
- */
-
-/* token */
-#define USB_PID_OUT		0xe1
-#define USB_PID_IN		0x69
-#define USB_PID_SOF		0xa5
-#define USB_PID_SETUP		0x2d
-/* handshake */
-#define USB_PID_ACK		0xd2
-#define USB_PID_NAK		0x5a
-#define USB_PID_STALL		0x1e
-#define USB_PID_NYET		0x96
-/* data */
-#define USB_PID_DATA0		0xc3
-#define USB_PID_DATA1		0x4b
-#define USB_PID_DATA2		0x87
-#define USB_PID_MDATA		0x0f
-/* Special */
-#define USB_PID_PREAMBLE	0x3c
-#define USB_PID_ERR		0x3c
-#define USB_PID_SPLIT		0x78
-#define USB_PID_PING		0xb4
-#define USB_PID_UNDEF_0		0xf0
-
-#define USB_PID_DATA_TOGGLE	0x88
-#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
-
-#define PCI_CAP_ID_EHCI_DEBUG	0xa
-
-#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
-#define HUB_SHORT_RESET_TIME	10
-#define HUB_LONG_RESET_TIME	200
-#define HUB_RESET_TIMEOUT	500
-
-#define DBGP_MAX_PACKET		8
-
-static int dbgp_wait_until_complete(void)
-{
-	u32 ctrl;
-	int loop = 0x100000;
-
-	do {
-		ctrl = readl(&ehci_debug->control);
-		/* Stop when the transaction is finished */
-		if (ctrl & DBGP_DONE)
-			break;
-	} while (--loop > 0);
-
-	if (!loop)
-		return -1;
-
-	/*
-	 * Now that we have observed the completed transaction,
-	 * clear the done bit.
-	 */
-	writel(ctrl | DBGP_DONE, &ehci_debug->control);
-	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
-}
-
-static void __init dbgp_mdelay(int ms)
-{
-	int i;
-
-	while (ms--) {
-		for (i = 0; i < 1000; i++)
-			outb(0x1, 0x80);
-	}
-}
-
-static void dbgp_breath(void)
-{
-	/* Sleep to give the debug port a chance to breathe */
-}
-
-static int dbgp_wait_until_done(unsigned ctrl)
-{
-	u32 pids, lpid;
-	int ret;
-	int loop = 3;
-
-retry:
-	writel(ctrl | DBGP_GO, &ehci_debug->control);
-	ret = dbgp_wait_until_complete();
-	pids = readl(&ehci_debug->pids);
-	lpid = DBGP_PID_GET(pids);
-
-	if (ret < 0)
-		return ret;
-
-	/*
-	 * If the port is getting full or it has dropped data
-	 * start pacing ourselves, not necessary but it's friendly.
-	 */
-	if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET))
-		dbgp_breath();
-
-	/* If I get a NACK reissue the transmission */
-	if (lpid == USB_PID_NAK) {
-		if (--loop > 0)
-			goto retry;
-	}
-
-	return ret;
-}
-
-static void dbgp_set_data(const void *buf, int size)
-{
-	const unsigned char *bytes = buf;
-	u32 lo, hi;
-	int i;
-
-	lo = hi = 0;
-	for (i = 0; i < 4 && i < size; i++)
-		lo |= bytes[i] << (8*i);
-	for (; i < 8 && i < size; i++)
-		hi |= bytes[i] << (8*(i - 4));
-	writel(lo, &ehci_debug->data03);
-	writel(hi, &ehci_debug->data47);
-}
-
-static void __init dbgp_get_data(void *buf, int size)
-{
-	unsigned char *bytes = buf;
-	u32 lo, hi;
-	int i;
-
-	lo = readl(&ehci_debug->data03);
-	hi = readl(&ehci_debug->data47);
-	for (i = 0; i < 4 && i < size; i++)
-		bytes[i] = (lo >> (8*i)) & 0xff;
-	for (; i < 8 && i < size; i++)
-		bytes[i] = (hi >> (8*(i - 4))) & 0xff;
-}
-
-static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
-			 const char *bytes, int size)
-{
-	u32 pids, addr, ctrl;
-	int ret;
-
-	if (size > DBGP_MAX_PACKET)
-		return -1;
-
-	addr = DBGP_EPADDR(devnum, endpoint);
-
-	pids = readl(&ehci_debug->pids);
-	pids = dbgp_pid_update(pids, USB_PID_OUT);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, size);
-	ctrl |= DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	dbgp_set_data(bytes, size);
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	return ret;
-}
-
-static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
-				 int size)
-{
-	u32 pids, addr, ctrl;
-	int ret;
-
-	if (size > DBGP_MAX_PACKET)
-		return -1;
-
-	addr = DBGP_EPADDR(devnum, endpoint);
-
-	pids = readl(&ehci_debug->pids);
-	pids = dbgp_pid_update(pids, USB_PID_IN);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, size);
-	ctrl &= ~DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	if (size > ret)
-		size = ret;
-	dbgp_get_data(data, size);
-	return ret;
-}
-
-static int __init dbgp_control_msg(unsigned devnum, int requesttype,
-	int request, int value, int index, void *data, int size)
-{
-	u32 pids, addr, ctrl;
-	struct usb_ctrlrequest req;
-	int read;
-	int ret;
-
-	read = (requesttype & USB_DIR_IN) != 0;
-	if (size > (read ? DBGP_MAX_PACKET:0))
-		return -1;
-
-	/* Compute the control message */
-	req.bRequestType = requesttype;
-	req.bRequest = request;
-	req.wValue = cpu_to_le16(value);
-	req.wIndex = cpu_to_le16(index);
-	req.wLength = cpu_to_le16(size);
-
-	pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
-	addr = DBGP_EPADDR(devnum, 0);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, sizeof(req));
-	ctrl |= DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	/* Send the setup message */
-	dbgp_set_data(&req, sizeof(req));
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	/* Read the result */
-	return dbgp_bulk_read(devnum, 0, data, size);
-}
-
-
-/* Find a PCI capability */
-static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap)
-{
-	u8 pos;
-	int bytes;
-
-	if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
-		PCI_STATUS_CAP_LIST))
-		return 0;
-
-	pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
-	for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
-		u8 id;
-
-		pos &= ~3;
-		id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
-		if (id == 0xff)
-			break;
-		if (id == cap)
-			return pos;
-
-		pos = read_pci_config_byte(num, slot, func,
-						 pos+PCI_CAP_LIST_NEXT);
-	}
-	return 0;
-}
-
-static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func)
-{
-	u32 class;
-
-	class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
-	if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI)
-		return 0;
-
-	return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
-}
-
-static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
-{
-	u32 bus, slot, func;
-
-	for (bus = 0; bus < 256; bus++) {
-		for (slot = 0; slot < 32; slot++) {
-			for (func = 0; func < 8; func++) {
-				unsigned cap;
-
-				cap = __find_dbgp(bus, slot, func);
-
-				if (!cap)
-					continue;
-				if (ehci_num-- != 0)
-					continue;
-				*rbus = bus;
-				*rslot = slot;
-				*rfunc = func;
-				return cap;
-			}
-		}
-	}
-	return 0;
-}
-
-static int __init ehci_reset_port(int port)
-{
-	u32 portsc;
-	u32 delay_time, delay;
-	int loop;
-
-	/* Reset the usb debug port */
-	portsc = readl(&ehci_regs->port_status[port - 1]);
-	portsc &= ~PORT_PE;
-	portsc |= PORT_RESET;
-	writel(portsc, &ehci_regs->port_status[port - 1]);
-
-	delay = HUB_ROOT_RESET_TIME;
-	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
-	     delay_time += delay) {
-		dbgp_mdelay(delay);
-
-		portsc = readl(&ehci_regs->port_status[port - 1]);
-		if (portsc & PORT_RESET) {
-			/* force reset to complete */
-			loop = 2;
-			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
-				&ehci_regs->port_status[port - 1]);
-			do {
-				portsc = readl(&ehci_regs->port_status[port-1]);
-			} while ((portsc & PORT_RESET) && (--loop > 0));
-		}
-
-		/* Device went away? */
-		if (!(portsc & PORT_CONNECT))
-			return -ENOTCONN;
-
-		/* bomb out completely if something weird happend */
-		if ((portsc & PORT_CSC))
-			return -EINVAL;
-
-		/* If we've finished resetting, then break out of the loop */
-		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
-			return 0;
-	}
-	return -EBUSY;
-}
-
-static int __init ehci_wait_for_port(int port)
-{
-	u32 status;
-	int ret, reps;
-
-	for (reps = 0; reps < 3; reps++) {
-		dbgp_mdelay(100);
-		status = readl(&ehci_regs->status);
-		if (status & STS_PCD) {
-			ret = ehci_reset_port(port);
-			if (ret == 0)
-				return 0;
-		}
-	}
-	return -ENOTCONN;
-}
-
-#ifdef DBGP_DEBUG
-# define dbgp_printk early_printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
-
-typedef void (*set_debug_port_t)(int port);
-
-static void __init default_set_debug_port(int port)
-{
-}
-
-static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
-
-static void __init nvidia_set_debug_port(int port)
-{
-	u32 dword;
-	dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
-				 0x74);
-	dword &= ~(0x0f<<12);
-	dword |= ((port & 0x0f)<<12);
-	write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74,
-				 dword);
-	dbgp_printk("set debug port to %d\n", port);
-}
-
-static void __init detect_set_debug_port(void)
-{
-	u32 vendorid;
-
-	vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
-		 0x00);
-
-	if ((vendorid & 0xffff) == 0x10de) {
-		dbgp_printk("using nvidia set_debug_port\n");
-		set_debug_port = nvidia_set_debug_port;
-	}
-}
-
-static int __init ehci_setup(void)
-{
-	struct usb_debug_descriptor dbgp_desc;
-	u32 cmd, ctrl, status, portsc, hcs_params;
-	u32 debug_port, new_debug_port = 0, n_ports;
-	u32  devnum;
-	int ret, i;
-	int loop;
-	int port_map_tried;
-	int playtimes = 3;
-
-try_next_time:
-	port_map_tried = 0;
-
-try_next_port:
-
-	hcs_params = readl(&ehci_caps->hcs_params);
-	debug_port = HCS_DEBUG_PORT(hcs_params);
-	n_ports    = HCS_N_PORTS(hcs_params);
-
-	dbgp_printk("debug_port: %d\n", debug_port);
-	dbgp_printk("n_ports:    %d\n", n_ports);
-
-	for (i = 1; i <= n_ports; i++) {
-		portsc = readl(&ehci_regs->port_status[i-1]);
-		dbgp_printk("portstatus%d: %08x\n", i, portsc);
-	}
-
-	if (port_map_tried && (new_debug_port != debug_port)) {
-		if (--playtimes) {
-			set_debug_port(new_debug_port);
-			goto try_next_time;
-		}
-		return -1;
-	}
-
-	loop = 10;
-	/* Reset the EHCI controller */
-	cmd = readl(&ehci_regs->command);
-	cmd |= CMD_RESET;
-	writel(cmd, &ehci_regs->command);
-	do {
-		cmd = readl(&ehci_regs->command);
-	} while ((cmd & CMD_RESET) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("can not reset ehci\n");
-		return -1;
-	}
-	dbgp_printk("ehci reset done\n");
-
-	/* Claim ownership, but do not enable yet */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_OWNER;
-	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
-	writel(ctrl, &ehci_debug->control);
-
-	/* Start the ehci running */
-	cmd = readl(&ehci_regs->command);
-	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
-	cmd |= CMD_RUN;
-	writel(cmd, &ehci_regs->command);
-
-	/* Ensure everything is routed to the EHCI */
-	writel(FLAG_CF, &ehci_regs->configured_flag);
-
-	/* Wait until the controller is no longer halted */
-	loop = 10;
-	do {
-		status = readl(&ehci_regs->status);
-	} while ((status & STS_HALT) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("ehci can be started\n");
-		return -1;
-	}
-	dbgp_printk("ehci started\n");
-
-	/* Wait for a device to show up in the debug port */
-	ret = ehci_wait_for_port(debug_port);
-	if (ret < 0) {
-		dbgp_printk("No device found in debug port\n");
-		goto next_debug_port;
-	}
-	dbgp_printk("ehci wait for port done\n");
-
-	/* Enable the debug port */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_CLAIM;
-	writel(ctrl, &ehci_debug->control);
-	ctrl = readl(&ehci_debug->control);
-	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
-		dbgp_printk("No device in debug port\n");
-		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
-		goto err;
-	}
-	dbgp_printk("debug ported enabled\n");
-
-	/* Completely transfer the debug device to the debug controller */
-	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
-	portsc &= ~PORT_PE;
-	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
-
-	dbgp_mdelay(100);
-
-	/* Find the debug device and make it device number 127 */
-	for (devnum = 0; devnum <= 127; devnum++) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
-			&dbgp_desc, sizeof(dbgp_desc));
-		if (ret > 0)
-			break;
-	}
-	if (devnum > 127) {
-		dbgp_printk("Could not find attached debug device\n");
-		goto err;
-	}
-	if (ret < 0) {
-		dbgp_printk("Attached device is not a debug device\n");
-		goto err;
-	}
-	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
-
-	/* Move the device to 127 if it isn't already there */
-	if (devnum != USB_DEBUG_DEVNUM) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
-		if (ret < 0) {
-			dbgp_printk("Could not move attached device to %d\n",
-				USB_DEBUG_DEVNUM);
-			goto err;
-		}
-		devnum = USB_DEBUG_DEVNUM;
-		dbgp_printk("debug device renamed to 127\n");
-	}
-
-	/* Enable the debug interface */
-	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
-		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
-	if (ret < 0) {
-		dbgp_printk(" Could not enable the debug device\n");
-		goto err;
-	}
-	dbgp_printk("debug interface enabled\n");
-
-	/* Perform a small write to get the even/odd data state in sync
-	 */
-	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
-	if (ret < 0) {
-		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
-		goto err;
-	}
-	dbgp_printk("small write doned\n");
-
-	return 0;
-err:
-	/* Things didn't work so remove my claim */
-	ctrl = readl(&ehci_debug->control);
-	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
-	writel(ctrl, &ehci_debug->control);
-	return -1;
-
-next_debug_port:
-	port_map_tried |= (1<<(debug_port - 1));
-	new_debug_port = ((debug_port-1+1)%n_ports) + 1;
-	if (port_map_tried != ((1<<n_ports) - 1)) {
-		set_debug_port(new_debug_port);
-		goto try_next_port;
-	}
-	if (--playtimes) {
-		set_debug_port(new_debug_port);
-		goto try_next_time;
-	}
-
-	return -1;
-}
-
-static int __init early_dbgp_init(char *s)
-{
-	u32 debug_port, bar, offset;
-	u32 bus, slot, func, cap;
-	void __iomem *ehci_bar;
-	u32 dbgp_num;
-	u32 bar_val;
-	char *e;
-	int ret;
-	u8 byte;
-
-	if (!early_pci_allowed())
-		return -1;
-
-	dbgp_num = 0;
-	if (*s)
-		dbgp_num = simple_strtoul(s, &e, 10);
-	dbgp_printk("dbgp_num: %d\n", dbgp_num);
-
-	cap = find_dbgp(dbgp_num, &bus, &slot, &func);
-	if (!cap)
-		return -1;
-
-	dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot,
-			 func);
-
-	debug_port = read_pci_config(bus, slot, func, cap);
-	bar = (debug_port >> 29) & 0x7;
-	bar = (bar * 4) + 0xc;
-	offset = (debug_port >> 16) & 0xfff;
-	dbgp_printk("bar: %02x offset: %03x\n", bar, offset);
-	if (bar != PCI_BASE_ADDRESS_0) {
-		dbgp_printk("only debug ports on bar 1 handled.\n");
-
-		return -1;
-	}
-
-	bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
-	dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset);
-	if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) {
-		dbgp_printk("only simple 32bit mmio bars supported\n");
-
-		return -1;
-	}
-
-	/* double check if the mem space is enabled */
-	byte = read_pci_config_byte(bus, slot, func, 0x04);
-	if (!(byte & 0x2)) {
-		byte  |= 0x02;
-		write_pci_config_byte(bus, slot, func, 0x04, byte);
-		dbgp_printk("mmio for ehci enabled\n");
-	}
-
-	/*
-	 * FIXME I don't have the bar size so just guess PAGE_SIZE is more
-	 * than enough.  1K is the biggest I have seen.
-	 */
-	set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK);
-	ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE);
-	ehci_bar += bar_val & ~PAGE_MASK;
-	dbgp_printk("ehci_bar: %p\n", ehci_bar);
-
-	ehci_caps  = ehci_bar;
-	ehci_regs  = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase));
-	ehci_debug = ehci_bar + offset;
-	ehci_dev.bus = bus;
-	ehci_dev.slot = slot;
-	ehci_dev.func = func;
-
-	detect_set_debug_port();
-
-	ret = ehci_setup();
-	if (ret < 0) {
-		dbgp_printk("ehci_setup failed\n");
-		ehci_debug = NULL;
-
-		return -1;
-	}
-
-	return 0;
-}
-
-static void early_dbgp_write(struct console *con, const char *str, u32 n)
-{
-	int chunk, ret;
-
-	if (!ehci_debug)
-		return;
-	while (n > 0) {
-		chunk = n;
-		if (chunk > DBGP_MAX_PACKET)
-			chunk = DBGP_MAX_PACKET;
-		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, str, chunk);
-		str += chunk;
-		n -= chunk;
-	}
-}
-
-static struct console early_dbgp_console = {
-	.name =		"earlydbg",
-	.write =	early_dbgp_write,
-	.flags =	CON_PRINTBUFFER,
-	.index =	-1,
-};
-#endif
-
 /* Direct interface for emergencies */
 static struct console *early_console = &early_vga_console;
 static int __initdata early_console_initialized;
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 19cb7d5..4e215ae 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_USB_MICROTEK)	+= image/
 obj-$(CONFIG_USB_SERIAL)	+= serial/
 
 obj-$(CONFIG_USB)		+= misc/
+obj-$(CONFIG_USB)		+= early/
 
 obj-$(CONFIG_USB_ATM)		+= atm/
 obj-$(CONFIG_USB_SPEEDTOUCH)	+= atm/
diff --git a/drivers/usb/early/Makefile b/drivers/usb/early/Makefile
new file mode 100644
index 0000000..dfedee8
--- /dev/null
+++ b/drivers/usb/early/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for early USB devices
+#
+
+obj-$(CONFIG_EARLY_PRINTK_DBGP)        += ehci-dbgp.o
diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
new file mode 100644
index 0000000..c7aa0aa
--- /dev/null
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -0,0 +1,723 @@
+#include <linux/console.h>
+#include <linux/errno.h>
+#include <linux/pci_regs.h>
+#include <linux/pci_ids.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/ehci_def.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+#include <asm/pci-direct.h>
+#include <asm/fixmap.h>
+
+static struct ehci_caps __iomem *ehci_caps;
+static struct ehci_regs __iomem *ehci_regs;
+static struct ehci_dbg_port __iomem *ehci_debug;
+static unsigned int dbgp_endpoint_out;
+
+struct ehci_dev {
+	u32 bus;
+	u32 slot;
+	u32 func;
+};
+
+static struct ehci_dev ehci_dev;
+
+#define USB_DEBUG_DEVNUM 127
+
+#define DBGP_DATA_TOGGLE	0x8800
+
+static inline u32 dbgp_pid_update(u32 x, u32 tok)
+{
+	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
+}
+
+static inline u32 dbgp_len_update(u32 x, u32 len)
+{
+	return (x & ~0x0f) | (len & 0x0f);
+}
+
+/*
+ * USB Packet IDs (PIDs)
+ */
+
+/* token */
+#define USB_PID_OUT		0xe1
+#define USB_PID_IN		0x69
+#define USB_PID_SOF		0xa5
+#define USB_PID_SETUP		0x2d
+/* handshake */
+#define USB_PID_ACK		0xd2
+#define USB_PID_NAK		0x5a
+#define USB_PID_STALL		0x1e
+#define USB_PID_NYET		0x96
+/* data */
+#define USB_PID_DATA0		0xc3
+#define USB_PID_DATA1		0x4b
+#define USB_PID_DATA2		0x87
+#define USB_PID_MDATA		0x0f
+/* Special */
+#define USB_PID_PREAMBLE	0x3c
+#define USB_PID_ERR		0x3c
+#define USB_PID_SPLIT		0x78
+#define USB_PID_PING		0xb4
+#define USB_PID_UNDEF_0		0xf0
+
+#define USB_PID_DATA_TOGGLE	0x88
+#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
+
+#define PCI_CAP_ID_EHCI_DEBUG	0xa
+
+#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
+#define HUB_SHORT_RESET_TIME	10
+#define HUB_LONG_RESET_TIME	200
+#define HUB_RESET_TIMEOUT	500
+
+#define DBGP_MAX_PACKET		8
+
+static int dbgp_wait_until_complete(void)
+{
+	u32 ctrl;
+	int loop = 0x100000;
+
+	do {
+		ctrl = readl(&ehci_debug->control);
+		/* Stop when the transaction is finished */
+		if (ctrl & DBGP_DONE)
+			break;
+	} while (--loop > 0);
+
+	if (!loop)
+		return -1;
+
+	/*
+	 * Now that we have observed the completed transaction,
+	 * clear the done bit.
+	 */
+	writel(ctrl | DBGP_DONE, &ehci_debug->control);
+	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
+}
+
+static void __init dbgp_mdelay(int ms)
+{
+	int i;
+
+	while (ms--) {
+		for (i = 0; i < 1000; i++)
+			outb(0x1, 0x80);
+	}
+}
+
+static void dbgp_breath(void)
+{
+	/* Sleep to give the debug port a chance to breathe */
+}
+
+static int dbgp_wait_until_done(unsigned ctrl)
+{
+	u32 pids, lpid;
+	int ret;
+	int loop = 3;
+
+retry:
+	writel(ctrl | DBGP_GO, &ehci_debug->control);
+	ret = dbgp_wait_until_complete();
+	pids = readl(&ehci_debug->pids);
+	lpid = DBGP_PID_GET(pids);
+
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * If the port is getting full or it has dropped data
+	 * start pacing ourselves, not necessary but it's friendly.
+	 */
+	if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET))
+		dbgp_breath();
+
+	/* If I get a NACK reissue the transmission */
+	if (lpid == USB_PID_NAK) {
+		if (--loop > 0)
+			goto retry;
+	}
+
+	return ret;
+}
+
+static void dbgp_set_data(const void *buf, int size)
+{
+	const unsigned char *bytes = buf;
+	u32 lo, hi;
+	int i;
+
+	lo = hi = 0;
+	for (i = 0; i < 4 && i < size; i++)
+		lo |= bytes[i] << (8*i);
+	for (; i < 8 && i < size; i++)
+		hi |= bytes[i] << (8*(i - 4));
+	writel(lo, &ehci_debug->data03);
+	writel(hi, &ehci_debug->data47);
+}
+
+static void __init dbgp_get_data(void *buf, int size)
+{
+	unsigned char *bytes = buf;
+	u32 lo, hi;
+	int i;
+
+	lo = readl(&ehci_debug->data03);
+	hi = readl(&ehci_debug->data47);
+	for (i = 0; i < 4 && i < size; i++)
+		bytes[i] = (lo >> (8*i)) & 0xff;
+	for (; i < 8 && i < size; i++)
+		bytes[i] = (hi >> (8*(i - 4))) & 0xff;
+}
+
+static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
+			 const char *bytes, int size)
+{
+	u32 pids, addr, ctrl;
+	int ret;
+
+	if (size > DBGP_MAX_PACKET)
+		return -1;
+
+	addr = DBGP_EPADDR(devnum, endpoint);
+
+	pids = readl(&ehci_debug->pids);
+	pids = dbgp_pid_update(pids, USB_PID_OUT);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, size);
+	ctrl |= DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	dbgp_set_data(bytes, size);
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	return ret;
+}
+
+static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
+				 int size)
+{
+	u32 pids, addr, ctrl;
+	int ret;
+
+	if (size > DBGP_MAX_PACKET)
+		return -1;
+
+	addr = DBGP_EPADDR(devnum, endpoint);
+
+	pids = readl(&ehci_debug->pids);
+	pids = dbgp_pid_update(pids, USB_PID_IN);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, size);
+	ctrl &= ~DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	if (size > ret)
+		size = ret;
+	dbgp_get_data(data, size);
+	return ret;
+}
+
+static int __init dbgp_control_msg(unsigned devnum, int requesttype,
+	int request, int value, int index, void *data, int size)
+{
+	u32 pids, addr, ctrl;
+	struct usb_ctrlrequest req;
+	int read;
+	int ret;
+
+	read = (requesttype & USB_DIR_IN) != 0;
+	if (size > (read ? DBGP_MAX_PACKET:0))
+		return -1;
+
+	/* Compute the control message */
+	req.bRequestType = requesttype;
+	req.bRequest = request;
+	req.wValue = cpu_to_le16(value);
+	req.wIndex = cpu_to_le16(index);
+	req.wLength = cpu_to_le16(size);
+
+	pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
+	addr = DBGP_EPADDR(devnum, 0);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, sizeof(req));
+	ctrl |= DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	/* Send the setup message */
+	dbgp_set_data(&req, sizeof(req));
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	/* Read the result */
+	return dbgp_bulk_read(devnum, 0, data, size);
+}
+
+
+/* Find a PCI capability */
+static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap)
+{
+	u8 pos;
+	int bytes;
+
+	if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
+		PCI_STATUS_CAP_LIST))
+		return 0;
+
+	pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
+	for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
+		u8 id;
+
+		pos &= ~3;
+		id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
+		if (id == 0xff)
+			break;
+		if (id == cap)
+			return pos;
+
+		pos = read_pci_config_byte(num, slot, func,
+						 pos+PCI_CAP_LIST_NEXT);
+	}
+	return 0;
+}
+
+static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func)
+{
+	u32 class;
+
+	class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
+	if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI)
+		return 0;
+
+	return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
+}
+
+static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
+{
+	u32 bus, slot, func;
+
+	for (bus = 0; bus < 256; bus++) {
+		for (slot = 0; slot < 32; slot++) {
+			for (func = 0; func < 8; func++) {
+				unsigned cap;
+
+				cap = __find_dbgp(bus, slot, func);
+
+				if (!cap)
+					continue;
+				if (ehci_num-- != 0)
+					continue;
+				*rbus = bus;
+				*rslot = slot;
+				*rfunc = func;
+				return cap;
+			}
+		}
+	}
+	return 0;
+}
+
+static int __init ehci_reset_port(int port)
+{
+	u32 portsc;
+	u32 delay_time, delay;
+	int loop;
+
+	/* Reset the usb debug port */
+	portsc = readl(&ehci_regs->port_status[port - 1]);
+	portsc &= ~PORT_PE;
+	portsc |= PORT_RESET;
+	writel(portsc, &ehci_regs->port_status[port - 1]);
+
+	delay = HUB_ROOT_RESET_TIME;
+	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
+	     delay_time += delay) {
+		dbgp_mdelay(delay);
+
+		portsc = readl(&ehci_regs->port_status[port - 1]);
+		if (portsc & PORT_RESET) {
+			/* force reset to complete */
+			loop = 2;
+			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
+				&ehci_regs->port_status[port - 1]);
+			do {
+				portsc = readl(&ehci_regs->port_status[port-1]);
+			} while ((portsc & PORT_RESET) && (--loop > 0));
+		}
+
+		/* Device went away? */
+		if (!(portsc & PORT_CONNECT))
+			return -ENOTCONN;
+
+		/* bomb out completely if something weird happend */
+		if ((portsc & PORT_CSC))
+			return -EINVAL;
+
+		/* If we've finished resetting, then break out of the loop */
+		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
+			return 0;
+	}
+	return -EBUSY;
+}
+
+static int __init ehci_wait_for_port(int port)
+{
+	u32 status;
+	int ret, reps;
+
+	for (reps = 0; reps < 3; reps++) {
+		dbgp_mdelay(100);
+		status = readl(&ehci_regs->status);
+		if (status & STS_PCD) {
+			ret = ehci_reset_port(port);
+			if (ret == 0)
+				return 0;
+		}
+	}
+	return -ENOTCONN;
+}
+
+#ifdef DBGP_DEBUG
+# define dbgp_printk early_printk
+#else
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
+typedef void (*set_debug_port_t)(int port);
+
+static void __init default_set_debug_port(int port)
+{
+}
+
+static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
+
+static void __init nvidia_set_debug_port(int port)
+{
+	u32 dword;
+	dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+				 0x74);
+	dword &= ~(0x0f<<12);
+	dword |= ((port & 0x0f)<<12);
+	write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74,
+				 dword);
+	dbgp_printk("set debug port to %d\n", port);
+}
+
+static void __init detect_set_debug_port(void)
+{
+	u32 vendorid;
+
+	vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+		 0x00);
+
+	if ((vendorid & 0xffff) == 0x10de) {
+		dbgp_printk("using nvidia set_debug_port\n");
+		set_debug_port = nvidia_set_debug_port;
+	}
+}
+
+static int __init ehci_setup(void)
+{
+	struct usb_debug_descriptor dbgp_desc;
+	u32 cmd, ctrl, status, portsc, hcs_params;
+	u32 debug_port, new_debug_port = 0, n_ports;
+	u32  devnum;
+	int ret, i;
+	int loop;
+	int port_map_tried;
+	int playtimes = 3;
+
+try_next_time:
+	port_map_tried = 0;
+
+try_next_port:
+
+	hcs_params = readl(&ehci_caps->hcs_params);
+	debug_port = HCS_DEBUG_PORT(hcs_params);
+	n_ports    = HCS_N_PORTS(hcs_params);
+
+	dbgp_printk("debug_port: %d\n", debug_port);
+	dbgp_printk("n_ports:    %d\n", n_ports);
+
+	for (i = 1; i <= n_ports; i++) {
+		portsc = readl(&ehci_regs->port_status[i-1]);
+		dbgp_printk("portstatus%d: %08x\n", i, portsc);
+	}
+
+	if (port_map_tried && (new_debug_port != debug_port)) {
+		if (--playtimes) {
+			set_debug_port(new_debug_port);
+			goto try_next_time;
+		}
+		return -1;
+	}
+
+	loop = 10;
+	/* Reset the EHCI controller */
+	cmd = readl(&ehci_regs->command);
+	cmd |= CMD_RESET;
+	writel(cmd, &ehci_regs->command);
+	do {
+		cmd = readl(&ehci_regs->command);
+	} while ((cmd & CMD_RESET) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("can not reset ehci\n");
+		return -1;
+	}
+	dbgp_printk("ehci reset done\n");
+
+	/* Claim ownership, but do not enable yet */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_OWNER;
+	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
+	writel(ctrl, &ehci_debug->control);
+
+	/* Start the ehci running */
+	cmd = readl(&ehci_regs->command);
+	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
+	cmd |= CMD_RUN;
+	writel(cmd, &ehci_regs->command);
+
+	/* Ensure everything is routed to the EHCI */
+	writel(FLAG_CF, &ehci_regs->configured_flag);
+
+	/* Wait until the controller is no longer halted */
+	loop = 10;
+	do {
+		status = readl(&ehci_regs->status);
+	} while ((status & STS_HALT) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("ehci can be started\n");
+		return -1;
+	}
+	dbgp_printk("ehci started\n");
+
+	/* Wait for a device to show up in the debug port */
+	ret = ehci_wait_for_port(debug_port);
+	if (ret < 0) {
+		dbgp_printk("No device found in debug port\n");
+		goto next_debug_port;
+	}
+	dbgp_printk("ehci wait for port done\n");
+
+	/* Enable the debug port */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_CLAIM;
+	writel(ctrl, &ehci_debug->control);
+	ctrl = readl(&ehci_debug->control);
+	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
+		dbgp_printk("No device in debug port\n");
+		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
+		goto err;
+	}
+	dbgp_printk("debug ported enabled\n");
+
+	/* Completely transfer the debug device to the debug controller */
+	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
+	portsc &= ~PORT_PE;
+	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
+
+	dbgp_mdelay(100);
+
+	/* Find the debug device and make it device number 127 */
+	for (devnum = 0; devnum <= 127; devnum++) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
+			&dbgp_desc, sizeof(dbgp_desc));
+		if (ret > 0)
+			break;
+	}
+	if (devnum > 127) {
+		dbgp_printk("Could not find attached debug device\n");
+		goto err;
+	}
+	if (ret < 0) {
+		dbgp_printk("Attached device is not a debug device\n");
+		goto err;
+	}
+	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
+
+	/* Move the device to 127 if it isn't already there */
+	if (devnum != USB_DEBUG_DEVNUM) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
+		if (ret < 0) {
+			dbgp_printk("Could not move attached device to %d\n",
+				USB_DEBUG_DEVNUM);
+			goto err;
+		}
+		devnum = USB_DEBUG_DEVNUM;
+		dbgp_printk("debug device renamed to 127\n");
+	}
+
+	/* Enable the debug interface */
+	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
+		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
+	if (ret < 0) {
+		dbgp_printk(" Could not enable the debug device\n");
+		goto err;
+	}
+	dbgp_printk("debug interface enabled\n");
+
+	/* Perform a small write to get the even/odd data state in sync
+	 */
+	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
+	if (ret < 0) {
+		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
+		goto err;
+	}
+	dbgp_printk("small write doned\n");
+
+	return 0;
+err:
+	/* Things didn't work so remove my claim */
+	ctrl = readl(&ehci_debug->control);
+	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
+	writel(ctrl, &ehci_debug->control);
+	return -1;
+
+next_debug_port:
+	port_map_tried |= (1<<(debug_port - 1));
+	new_debug_port = ((debug_port-1+1)%n_ports) + 1;
+	if (port_map_tried != ((1<<n_ports) - 1)) {
+		set_debug_port(new_debug_port);
+		goto try_next_port;
+	}
+	if (--playtimes) {
+		set_debug_port(new_debug_port);
+		goto try_next_time;
+	}
+
+	return -1;
+}
+
+int __init early_dbgp_init(char *s)
+{
+	u32 debug_port, bar, offset;
+	u32 bus, slot, func, cap;
+	void __iomem *ehci_bar;
+	u32 dbgp_num;
+	u32 bar_val;
+	char *e;
+	int ret;
+	u8 byte;
+
+	if (!early_pci_allowed())
+		return -1;
+
+	dbgp_num = 0;
+	if (*s)
+		dbgp_num = simple_strtoul(s, &e, 10);
+	dbgp_printk("dbgp_num: %d\n", dbgp_num);
+
+	cap = find_dbgp(dbgp_num, &bus, &slot, &func);
+	if (!cap)
+		return -1;
+
+	dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot,
+			 func);
+
+	debug_port = read_pci_config(bus, slot, func, cap);
+	bar = (debug_port >> 29) & 0x7;
+	bar = (bar * 4) + 0xc;
+	offset = (debug_port >> 16) & 0xfff;
+	dbgp_printk("bar: %02x offset: %03x\n", bar, offset);
+	if (bar != PCI_BASE_ADDRESS_0) {
+		dbgp_printk("only debug ports on bar 1 handled.\n");
+
+		return -1;
+	}
+
+	bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
+	dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset);
+	if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) {
+		dbgp_printk("only simple 32bit mmio bars supported\n");
+
+		return -1;
+	}
+
+	/* double check if the mem space is enabled */
+	byte = read_pci_config_byte(bus, slot, func, 0x04);
+	if (!(byte & 0x2)) {
+		byte  |= 0x02;
+		write_pci_config_byte(bus, slot, func, 0x04, byte);
+		dbgp_printk("mmio for ehci enabled\n");
+	}
+
+	/*
+	 * FIXME I don't have the bar size so just guess PAGE_SIZE is more
+	 * than enough.  1K is the biggest I have seen.
+	 */
+	set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK);
+	ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE);
+	ehci_bar += bar_val & ~PAGE_MASK;
+	dbgp_printk("ehci_bar: %p\n", ehci_bar);
+
+	ehci_caps  = ehci_bar;
+	ehci_regs  = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase));
+	ehci_debug = ehci_bar + offset;
+	ehci_dev.bus = bus;
+	ehci_dev.slot = slot;
+	ehci_dev.func = func;
+
+	detect_set_debug_port();
+
+	ret = ehci_setup();
+	if (ret < 0) {
+		dbgp_printk("ehci_setup failed\n");
+		ehci_debug = NULL;
+
+		return -1;
+	}
+
+	return 0;
+}
+
+static void early_dbgp_write(struct console *con, const char *str, u32 n)
+{
+	int chunk, ret;
+
+	if (!ehci_debug)
+		return;
+	while (n > 0) {
+		chunk = n;
+		if (chunk > DBGP_MAX_PACKET)
+			chunk = DBGP_MAX_PACKET;
+		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
+			dbgp_endpoint_out, str, chunk);
+		str += chunk;
+		n -= chunk;
+	}
+}
+
+struct console early_dbgp_console = {
+	.name =		"earlydbg",
+	.write =	early_dbgp_write,
+	.flags =	CON_PRINTBUFFER,
+	.index =	-1,
+};
+
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 5b88e36..0e22b5f 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -157,4 +157,10 @@ struct ehci_dbg_port {
 #define DBGP_EPADDR(dev, ep)	(((dev)<<8)|(ep))
 } __attribute__ ((packed));
 
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+#include <linux/init.h>
+extern int __init early_dbgp_init(char *s);
+extern struct console early_dbgp_console;
+#endif /* CONFIG_EARLY_PRINTK_DBGP */
+
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

[PATCH 02/10] usb,early_printk: insert cr prior to nl as needed

[Jason Wessel]

The rs232 drivers send a carriage return prior to a new line in the
early printk code.

The usb debug driver should do the same because you want to be able to
use the same terminal programs and tools for analysis of early printk
data.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   22 ++++++++++++++++------
 1 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index c7aa0aa..51ec414 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -700,17 +700,27 @@ int __init early_dbgp_init(char *s)
 static void early_dbgp_write(struct console *con, const char *str, u32 n)
 {
 	int chunk, ret;
+	char buf[DBGP_MAX_PACKET];
+	int use_cr = 0;
 
 	if (!ehci_debug)
 		return;
 	while (n > 0) {
-		chunk = n;
-		if (chunk > DBGP_MAX_PACKET)
-			chunk = DBGP_MAX_PACKET;
+		for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0;
+		     str++, chunk++, n--) {
+			if (!use_cr && *str == '\n') {
+				use_cr = 1;
+				buf[chunk] = '\r';
+				str--;
+				n++;
+				continue;
+			}
+			if (use_cr)
+				use_cr = 0;
+			buf[chunk] = *str;
+		}
 		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, str, chunk);
-		str += chunk;
-		n -= chunk;
+			dbgp_endpoint_out, buf, chunk);
 	}
 }
 
-- 
1.6.0.3.523.g304d0

[PATCH 03/10] ehci-dbgp: Execute early BIOS hand off

[Jason Wessel]

The PCI quirk code executes a BIOS hand off to obtain full control of
the EHCI host controller, the self contained ehci-dbgp driver must do
the same thing using the early PCI API, else the BIOS can cause a
fatal fault.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   49 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 49 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 51ec414..f4bfe31 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -435,6 +435,53 @@ static void __init detect_set_debug_port(void)
 	}
 }
 
+/* The code in early_ehci_bios_handoff() is derived from the usb pci
+ * quirk initialization, but altered so as to use the early PCI
+ * routines. */
+#define EHCI_USBLEGSUP_BIOS	(1 << 16)	/* BIOS semaphore */
+#define EHCI_USBLEGCTLSTS	4		/* legacy control/status */
+static void __init early_ehci_bios_handoff(void)
+{
+	u32 hcc_params = readl(&ehci_caps->hcc_params);
+	int offset = (hcc_params >> 8) & 0xff;
+	u32 cap;
+	int msec;
+
+	if (!offset)
+		return;
+
+	cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+			      ehci_dev.func, offset);
+	dbgp_printk("dbgp: ehci BIOS state %08x\n", cap);
+
+	if ((cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS)) {
+		dbgp_printk("dbgp: BIOS handoff\n");
+		write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset + 3, 1);
+	}
+
+	/* if boot firmware now owns EHCI, spin till it hands it over. */
+	msec = 1000;
+	while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
+		mdelay(10);
+		msec -= 10;
+		cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset);
+	}
+
+	if (cap & EHCI_USBLEGSUP_BIOS) {
+		/* well, possibly buggy BIOS... try to shut it down,
+		 * and hope nothing goes too wrong */
+		dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap);
+		write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset + 2, 0);
+	}
+
+	/* just in case, always disable EHCI SMIs */
+	write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+			      offset + EHCI_USBLEGCTLSTS, 0);
+}
+
 static int __init ehci_setup(void)
 {
 	struct usb_debug_descriptor dbgp_desc;
@@ -446,6 +493,8 @@ static int __init ehci_setup(void)
 	int port_map_tried;
 	int playtimes = 3;
 
+	early_ehci_bios_handoff();
+
 try_next_time:
 	port_map_tried = 0;
 
-- 
1.6.0.3.523.g304d0

[PATCH 04/10] usb,early_printk: EHCI debug controller initialization delays

[Jason Wessel]

When using the EHCI host controller as a polled device, a bit more
tolerance is required in terms of delays.  On some 3+ghz systems the
cpu loops were faster than the EHCI device mmio and resulted in the
controller failing to initialize.

On at least one first generation EHCI controller when it was not
operating in interrupt mode, it would fail to report a port change
status, but executing the port reset allowed the debug controller to
work correctly anyway.  This errata causes a one time 300ms delay in
the boot time, where as the typical delay is 1-5ms for an EHCI
controller that does not have this errata.

The debug printk's were fixed to have the correct state messages, and
there was a conversion from using early_printk to printk to avoid
calling the dbgp driver while debugging the initialization.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   45 +++++++++++++++++++++++-----------------
 1 files changed, 26 insertions(+), 19 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index f4bfe31..6198ebd 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -9,6 +9,12 @@
 #include <asm/pci-direct.h>
 #include <asm/fixmap.h>
 
+#ifdef DBGP_DEBUG
+# define dbgp_printk printk
+#else
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
 static struct ehci_caps __iomem *ehci_caps;
 static struct ehci_regs __iomem *ehci_regs;
 static struct ehci_dbg_port __iomem *ehci_debug;
@@ -342,6 +348,7 @@ static int __init ehci_reset_port(int port)
 	u32 delay_time, delay;
 	int loop;
 
+	dbgp_printk("ehci_reset_port %i\n", port);
 	/* Reset the usb debug port */
 	portsc = readl(&ehci_regs->port_status[port - 1]);
 	portsc &= ~PORT_PE;
@@ -352,14 +359,17 @@ static int __init ehci_reset_port(int port)
 	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
 	     delay_time += delay) {
 		dbgp_mdelay(delay);
-
 		portsc = readl(&ehci_regs->port_status[port - 1]);
+		if (!(portsc & PORT_RESET))
+			break;
+	}
 		if (portsc & PORT_RESET) {
 			/* force reset to complete */
-			loop = 2;
+			loop = 100 * 1000;
 			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
 				&ehci_regs->port_status[port - 1]);
 			do {
+				udelay(1);
 				portsc = readl(&ehci_regs->port_status[port-1]);
 			} while ((portsc & PORT_RESET) && (--loop > 0));
 		}
@@ -375,7 +385,6 @@ static int __init ehci_reset_port(int port)
 		/* If we've finished resetting, then break out of the loop */
 		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
 			return 0;
-	}
 	return -EBUSY;
 }
 
@@ -384,24 +393,18 @@ static int __init ehci_wait_for_port(int port)
 	u32 status;
 	int ret, reps;
 
-	for (reps = 0; reps < 3; reps++) {
-		dbgp_mdelay(100);
+	for (reps = 0; reps < 300; reps++) {
 		status = readl(&ehci_regs->status);
-		if (status & STS_PCD) {
-			ret = ehci_reset_port(port);
-			if (ret == 0)
-				return 0;
-		}
+		if (status & STS_PCD)
+			break;
+		dbgp_mdelay(1);
 	}
+	ret = ehci_reset_port(port);
+	if (ret == 0)
+		return 0;
 	return -ENOTCONN;
 }
 
-#ifdef DBGP_DEBUG
-# define dbgp_printk early_printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
-
 typedef void (*set_debug_port_t)(int port);
 
 static void __init default_set_debug_port(int port)
@@ -520,7 +523,7 @@ try_next_port:
 		return -1;
 	}
 
-	loop = 10;
+	loop = 250 * 1000;
 	/* Reset the EHCI controller */
 	cmd = readl(&ehci_regs->command);
 	cmd |= CMD_RESET;
@@ -540,6 +543,7 @@ try_next_port:
 	ctrl |= DBGP_OWNER;
 	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
 	writel(ctrl, &ehci_debug->control);
+	udelay(1);
 
 	/* Start the ehci running */
 	cmd = readl(&ehci_regs->command);
@@ -554,10 +558,13 @@ try_next_port:
 	loop = 10;
 	do {
 		status = readl(&ehci_regs->status);
-	} while ((status & STS_HALT) && (--loop > 0));
+		if (!(status & STS_HALT))
+			break;
+		udelay(1);
+	} while (--loop > 0);
 
 	if (!loop) {
-		dbgp_printk("ehci can be started\n");
+		dbgp_printk("ehci can not be started\n");
 		return -1;
 	}
 	dbgp_printk("ehci started\n");
-- 
1.6.0.3.523.g304d0

[PATCH 05/10] printk,early_printk,console: Allow more than one early console

[Jason Wessel]

It is very nice to be able to use one early boot device to debug
another or to have multiple places you can see the early boot
diagnostics, such as the vga screen or serial device.

This patch changes the early_printk console device registration to
allow more than one early printk device to get registered via
register_console().

A corresponding change is required to the console registration code
such that it will properly unregister any console marked with the
CON_BOOT flag via a simple loop during a console handover or at late
init time.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
---
 arch/x86/kernel/early_printk.c |   65 ++++++++++++++++++++-------------------
 kernel/printk.c                |   41 ++++++++++++++++---------
 2 files changed, 59 insertions(+), 47 deletions(-)

diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index 519a5e1..2acfd3f 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -176,10 +176,19 @@ asmlinkage void early_printk(const char *fmt, ...)
 	va_end(ap);
 }
 
+static inline void early_console_register(struct console *con, int keep_early)
+{
+	early_console = con;
+	if (keep_early)
+		early_console->flags &= ~CON_BOOT;
+	else
+		early_console->flags |= CON_BOOT;
+	register_console(early_console);
+}
 
 static int __init setup_early_printk(char *buf)
 {
-	int keep_early;
+	int keep;
 
 	if (!buf)
 		return 0;
@@ -188,42 +197,34 @@ static int __init setup_early_printk(char *buf)
 		return 0;
 	early_console_initialized = 1;
 
-	keep_early = (strstr(buf, "keep") != NULL);
-
-	if (!strncmp(buf, "serial", 6)) {
-		early_serial_init(buf + 6);
-		early_console = &early_serial_console;
-	} else if (!strncmp(buf, "ttyS", 4)) {
-		early_serial_init(buf);
-		early_console = &early_serial_console;
-	} else if (!strncmp(buf, "vga", 3)
-		&& boot_params.screen_info.orig_video_isVGA == 1) {
-		max_xpos = boot_params.screen_info.orig_video_cols;
-		max_ypos = boot_params.screen_info.orig_video_lines;
-		current_ypos = boot_params.screen_info.orig_y;
-		early_console = &early_vga_console;
+	keep = (strstr(buf, "keep") != NULL);
+
+	while (*buf != '\0') {
+		if (!strncmp(buf, "serial", 6)) {
+			early_serial_init(buf + 6);
+			early_console_register(&early_serial_console, keep);
+		}
+		if (!strncmp(buf, "ttyS", 4)) {
+			early_serial_init(buf + 4);
+			early_console_register(&early_serial_console, keep);
+		}
+		if (!strncmp(buf, "vga", 3) &&
+		    boot_params.screen_info.orig_video_isVGA == 1) {
+			max_xpos = boot_params.screen_info.orig_video_cols;
+			max_ypos = boot_params.screen_info.orig_video_lines;
+			current_ypos = boot_params.screen_info.orig_y;
+			early_console_register(&early_vga_console, keep);
+		}
 #ifdef CONFIG_EARLY_PRINTK_DBGP
-	} else if (!strncmp(buf, "dbgp", 4)) {
-		if (early_dbgp_init(buf+4) < 0)
-			return 0;
-		early_console = &early_dbgp_console;
-		/*
-		 * usb subsys will reset ehci controller, so don't keep
-		 * that early console
-		 */
-		keep_early = 0;
+		if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
+			early_console_register(&early_dbgp_console, keep);
 #endif
 #ifdef CONFIG_HVC_XEN
-	} else if (!strncmp(buf, "xen", 3)) {
-		early_console = &xenboot_console;
+		if (!strncmp(buf, "xen", 3))
+			early_console_register(&xenboot_console, keep);
 #endif
+		buf++;
 	}
-
-	if (keep_early)
-		early_console->flags &= ~CON_BOOT;
-	else
-		early_console->flags |= CON_BOOT;
-	register_console(early_console);
 	return 0;
 }
 
diff --git a/kernel/printk.c b/kernel/printk.c
index b4d97b5..45e0cec 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1129,6 +1129,28 @@ void console_start(struct console *console)
 }
 EXPORT_SYMBOL(console_start);
 
+static int disable_boot_consoles(void)
+{
+	struct console *bootconsole = console_drivers;
+	struct console *nextcon;
+	if (!bootconsole)
+		return 0;
+	while (bootconsole) {
+		nextcon = bootconsole->next;
+		if (bootconsole->flags & CON_BOOT) {
+			printk(KERN_INFO "turn off boot console %s%d\n",
+			       console_drivers->name, console_drivers->index);
+			if (unregister_console(bootconsole) != 0)
+				printk(KERN_ERR "ERROR unregistering %s%d\n",
+				       console_drivers->name,
+				       console_drivers->index);
+		}
+		bootconsole = nextcon;
+	}
+	return 0;
+}
+late_initcall(disable_boot_consoles);
+
 /*
  * The console driver calls this routine during kernel initialization
  * to register the console printing procedure with printk() and to
@@ -1142,8 +1164,7 @@ void register_console(struct console *console)
 	struct console *bootconsole = NULL;
 
 	if (console_drivers) {
-		if (console->flags & CON_BOOT)
-			return;
+
 		if (console_drivers->flags & CON_BOOT)
 			bootconsole = console_drivers;
 	}
@@ -1216,6 +1237,7 @@ void register_console(struct console *console)
 		       console->name, console->index);
 		unregister_console(bootconsole);
 		console->flags &= ~CON_PRINTBUFFER;
+		disable_boot_consoles();
 	} else {
 		printk(KERN_INFO "console [%s%d] enabled\n",
 		       console->name, console->index);
@@ -1280,24 +1302,13 @@ int unregister_console(struct console *console)
 	if (console_drivers != NULL && console->flags & CON_CONSDEV)
 		console_drivers->flags |= CON_CONSDEV;
 
+	if (!res)
+		console->index = -1;
 	release_console_sem();
 	return res;
 }
 EXPORT_SYMBOL(unregister_console);
 
-static int __init disable_boot_consoles(void)
-{
-	if (console_drivers != NULL) {
-		if (console_drivers->flags & CON_BOOT) {
-			printk(KERN_INFO "turn off boot console %s%d\n",
-				console_drivers->name, console_drivers->index);
-			return unregister_console(console_drivers);
-		}
-	}
-	return 0;
-}
-late_initcall(disable_boot_consoles);
-
 #if defined CONFIG_PRINTK
 
 /*
-- 
1.6.0.3.523.g304d0

[PATCH 06/10] ehci-dbgp: stability improvements and external re-init

[Jason Wessel]

This patch implements several changes:

1) Improve the capability to debug the dbgp driver

   The dbgp_ehci_status() was added in a number of places to report
   the critical ehci registers to diagnose the cause of a failure of
   the ehci-dbgp driver.

2) Capability to survive the host controller initialization

   The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were
   added so as to allow the ehci-dbgp to re-initialize after the ehci
   host controller is reset by the standard host controller driver.
   This same routine is common for the early startup or
   re-initialization.

   This resulted in the need to move some of the initialization code
   out of the __init section because the ehci driver has the
   possibility to be loaded later on as a kernel module.

3) Stability improvements for device initialization

   The device enumeration from 0 to 127 has the possibility to fail
   the first time after a warm reset on some older EHCI debug
   controllers.  The enumeration will be tried up to 3 times to
   account for this failure case.

   The dbg_wait_until_complete() was changed to wait up to 250 ms
   before failing which only comes into play during device
   initialization. The maximum delay will never get hit during the
   course of normal operation of the driver, unless the device got
   unplugged or there was a ehci controller failure, in which case the
   dbgp device driver will shut itself down.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |  442 +++++++++++++++++++++++++++--------------
 include/linux/usb/ehci_def.h  |    5 +
 2 files changed, 299 insertions(+), 148 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 6198ebd..06e05ea 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -1,5 +1,19 @@
+/*
+ * Standalone EHCI usb debug driver
+ *
+ * Originally written by:
+ *  Eric W. Biederman" <ebiederm@xmission.com> and
+ *  Yinghai Lu <yhlu.kernel@gmail.com>
+ *
+ * Changes for early/late printk and HW errata:
+ *  Jason Wessel <jason.wessel@windriver.com>
+ *  Copyright (C) 2009 Wind River Systems, Inc.
+ *
+ */
+
 #include <linux/console.h>
 #include <linux/errno.h>
+#include <linux/module.h>
 #include <linux/pci_regs.h>
 #include <linux/pci_ids.h>
 #include <linux/usb/ch9.h>
@@ -9,15 +23,37 @@
 #include <asm/pci-direct.h>
 #include <asm/fixmap.h>
 
-#ifdef DBGP_DEBUG
-# define dbgp_printk printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
+/* The code here is intended to talk directly to the EHCI debug port
+ * and does not require that you have any kind of USB host controller
+ * drivers or USB device drivers compiled into the kernel.
+ *
+ * If you make a change to anything in here, the following test cases
+ * need to pass where a USB debug device works in the following
+ * configurations.
+ *
+ * 1. boot args:  earlyprintk=dbgp
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ * 2. boot args: earlyprintk=dbgp,keep
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ * 3. boot args: earlyprintk=dbgp console=ttyUSB0
+ *     o kernel has CONFIG_USB_EHCI_HCD=y and
+ *       CONFIG_USB_SERIAL_DEBUG=y
+ * 4. boot args: earlyprintk=vga,dbgp
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ *
+ * For the 4th configuration you can turn on or off the DBGP_DEBUG
+ * such that you can debug the dbgp device's driver code.
+ */
+
+static int dbgp_phys_port = 1;
 
 static struct ehci_caps __iomem *ehci_caps;
 static struct ehci_regs __iomem *ehci_regs;
 static struct ehci_dbg_port __iomem *ehci_debug;
+static int dbgp_not_safe; /* Cannot use debug device during ehci reset */
 static unsigned int dbgp_endpoint_out;
 
 struct ehci_dev {
@@ -32,6 +68,26 @@ static struct ehci_dev ehci_dev;
 
 #define DBGP_DATA_TOGGLE	0x8800
 
+#ifdef DBGP_DEBUG
+#define dbgp_printk printk
+static void dbgp_ehci_status(char *str)
+{
+	if (!ehci_debug)
+		return;
+	dbgp_printk("dbgp: %s\n", str);
+	dbgp_printk("  Debug control: %08x", readl(&ehci_debug->control));
+	dbgp_printk("  ehci cmd     : %08x", readl(&ehci_regs->command));
+	dbgp_printk("  ehci conf flg: %08x\n",
+		    readl(&ehci_regs->configured_flag));
+	dbgp_printk("  ehci status  : %08x", readl(&ehci_regs->status));
+	dbgp_printk("  ehci portsc  : %08x\n",
+		    readl(&ehci_regs->port_status[dbgp_phys_port - 1]));
+}
+#else
+static inline void dbgp_ehci_status(char *str) { }
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
 static inline u32 dbgp_pid_update(u32 x, u32 tok)
 {
 	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
@@ -79,21 +135,23 @@ static inline u32 dbgp_len_update(u32 x, u32 len)
 #define HUB_RESET_TIMEOUT	500
 
 #define DBGP_MAX_PACKET		8
+#define DBGP_TIMEOUT		(250 * 1000)
 
 static int dbgp_wait_until_complete(void)
 {
 	u32 ctrl;
-	int loop = 0x100000;
+	int loop = DBGP_TIMEOUT;
 
 	do {
 		ctrl = readl(&ehci_debug->control);
 		/* Stop when the transaction is finished */
 		if (ctrl & DBGP_DONE)
 			break;
+		udelay(1);
 	} while (--loop > 0);
 
 	if (!loop)
-		return -1;
+		return -DBGP_TIMEOUT;
 
 	/*
 	 * Now that we have observed the completed transaction,
@@ -103,7 +161,7 @@ static int dbgp_wait_until_complete(void)
 	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
 }
 
-static void __init dbgp_mdelay(int ms)
+static inline void dbgp_mdelay(int ms)
 {
 	int i;
 
@@ -130,8 +188,17 @@ retry:
 	pids = readl(&ehci_debug->pids);
 	lpid = DBGP_PID_GET(pids);
 
-	if (ret < 0)
+	if (ret < 0) {
+		/* A -DBGP_TIMEOUT failure here means the device has
+		 * failed, perhaps because it was unplugged, in which
+		 * case we do not want to hang the system so the dbgp
+		 * will be marked as unsafe to use.  EHCI reset is the
+		 * only way to recover if you unplug the dbgp device.
+		 */
+		if (ret == -DBGP_TIMEOUT && !dbgp_not_safe)
+			dbgp_not_safe = 1;
 		return ret;
+	}
 
 	/*
 	 * If the port is getting full or it has dropped data
@@ -149,7 +216,7 @@ retry:
 	return ret;
 }
 
-static void dbgp_set_data(const void *buf, int size)
+static inline void dbgp_set_data(const void *buf, int size)
 {
 	const unsigned char *bytes = buf;
 	u32 lo, hi;
@@ -164,7 +231,7 @@ static void dbgp_set_data(const void *buf, int size)
 	writel(hi, &ehci_debug->data47);
 }
 
-static void __init dbgp_get_data(void *buf, int size)
+static inline void dbgp_get_data(void *buf, int size)
 {
 	unsigned char *bytes = buf;
 	u32 lo, hi;
@@ -208,7 +275,7 @@ static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
 	return ret;
 }
 
-static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
+static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
 				 int size)
 {
 	u32 pids, addr, ctrl;
@@ -239,7 +306,7 @@ static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
 	return ret;
 }
 
-static int __init dbgp_control_msg(unsigned devnum, int requesttype,
+static int dbgp_control_msg(unsigned devnum, int requesttype,
 	int request, int value, int index, void *data, int size)
 {
 	u32 pids, addr, ctrl;
@@ -342,13 +409,179 @@ static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
 	return 0;
 }
 
+static int dbgp_ehci_startup(void)
+{
+	u32 ctrl, cmd, status;
+	int loop;
+
+	/* Claim ownership, but do not enable yet */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_OWNER;
+	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
+	writel(ctrl, &ehci_debug->control);
+	udelay(1);
+
+	dbgp_ehci_status("EHCI startup");
+	/* Start the ehci running */
+	cmd = readl(&ehci_regs->command);
+	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
+	cmd |= CMD_RUN;
+	writel(cmd, &ehci_regs->command);
+
+	/* Ensure everything is routed to the EHCI */
+	writel(FLAG_CF, &ehci_regs->configured_flag);
+
+	/* Wait until the controller is no longer halted */
+	loop = 10;
+	do {
+		status = readl(&ehci_regs->status);
+		if (!(status & STS_HALT))
+			break;
+		udelay(1);
+	} while (--loop > 0);
+
+	if (!loop) {
+		dbgp_printk("ehci can not be started\n");
+		return -ENODEV;
+	}
+	dbgp_printk("ehci started\n");
+	return 0;
+}
+
+static int dbgp_ehci_controller_reset(void)
+{
+	int loop = 250 * 1000;
+	u32 cmd;
+
+	/* Reset the EHCI controller */
+	cmd = readl(&ehci_regs->command);
+	cmd |= CMD_RESET;
+	writel(cmd, &ehci_regs->command);
+	do {
+		cmd = readl(&ehci_regs->command);
+	} while ((cmd & CMD_RESET) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("can not reset ehci\n");
+		return -1;
+	}
+	dbgp_ehci_status("ehci reset done");
+	return 0;
+}
+static int ehci_wait_for_port(int port);
+/* Return 0 on success
+ * Return -ENODEV for any general failure
+ * Return -EIO if wait for port fails
+ */
+int dbgp_external_startup(void)
+{
+	int devnum;
+	struct usb_debug_descriptor dbgp_desc;
+	int ret;
+	u32 ctrl, portsc;
+	int dbg_port = dbgp_phys_port;
+	int tries = 3;
+
+	ret = dbgp_ehci_startup();
+	if (ret)
+		return ret;
+
+	/* Wait for a device to show up in the debug port */
+	ret = ehci_wait_for_port(dbg_port);
+	if (ret < 0) {
+		portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+		dbgp_printk("No device found in debug port\n");
+		return -EIO;
+	}
+	dbgp_ehci_status("wait for port done");
+
+	/* Enable the debug port */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_CLAIM;
+	writel(ctrl, &ehci_debug->control);
+	ctrl = readl(&ehci_debug->control);
+	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
+		dbgp_printk("No device in debug port\n");
+		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
+		return -ENODEV;
+	}
+	dbgp_ehci_status("debug ported enabled");
+
+	/* Completely transfer the debug device to the debug controller */
+	portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+	portsc &= ~PORT_PE;
+	writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
+
+	dbgp_mdelay(100);
+
+try_again:
+	/* Find the debug device and make it device number 127 */
+	for (devnum = 0; devnum <= 127; devnum++) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
+			&dbgp_desc, sizeof(dbgp_desc));
+		if (ret > 0)
+			break;
+	}
+	if (devnum > 127) {
+		dbgp_printk("Could not find attached debug device\n");
+		goto err;
+	}
+	if (ret < 0) {
+		dbgp_printk("Attached device is not a debug device\n");
+		goto err;
+	}
+	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
+
+	/* Move the device to 127 if it isn't already there */
+	if (devnum != USB_DEBUG_DEVNUM) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
+		if (ret < 0) {
+			dbgp_printk("Could not move attached device to %d\n",
+				USB_DEBUG_DEVNUM);
+			goto err;
+		}
+		devnum = USB_DEBUG_DEVNUM;
+		dbgp_printk("debug device renamed to 127\n");
+	}
+
+	/* Enable the debug interface */
+	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
+		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
+	if (ret < 0) {
+		dbgp_printk(" Could not enable the debug device\n");
+		goto err;
+	}
+	dbgp_printk("debug interface enabled\n");
+	/* Perform a small write to get the even/odd data state in sync
+	 */
+	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
+	if (ret < 0) {
+		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
+		goto err;
+	}
+	dbgp_printk("small write doned\n");
+	dbgp_not_safe = 0;
+
+	return 0;
+err:
+	if (tries--)
+		goto try_again;
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(dbgp_external_startup);
+
 static int __init ehci_reset_port(int port)
 {
 	u32 portsc;
 	u32 delay_time, delay;
 	int loop;
 
-	dbgp_printk("ehci_reset_port %i\n", port);
+	dbgp_ehci_status("reset port");
 	/* Reset the usb debug port */
 	portsc = readl(&ehci_regs->port_status[port - 1]);
 	portsc &= ~PORT_PE;
@@ -388,7 +621,7 @@ static int __init ehci_reset_port(int port)
 	return -EBUSY;
 }
 
-static int __init ehci_wait_for_port(int port)
+static int ehci_wait_for_port(int port)
 {
 	u32 status;
 	int ret, reps;
@@ -487,12 +720,9 @@ static void __init early_ehci_bios_handoff(void)
 
 static int __init ehci_setup(void)
 {
-	struct usb_debug_descriptor dbgp_desc;
-	u32 cmd, ctrl, status, portsc, hcs_params;
+	u32 ctrl, portsc, hcs_params;
 	u32 debug_port, new_debug_port = 0, n_ports;
-	u32  devnum;
 	int ret, i;
-	int loop;
 	int port_map_tried;
 	int playtimes = 3;
 
@@ -505,10 +735,12 @@ try_next_port:
 
 	hcs_params = readl(&ehci_caps->hcs_params);
 	debug_port = HCS_DEBUG_PORT(hcs_params);
+	dbgp_phys_port = debug_port;
 	n_ports    = HCS_N_PORTS(hcs_params);
 
 	dbgp_printk("debug_port: %d\n", debug_port);
 	dbgp_printk("n_ports:    %d\n", n_ports);
+	dbgp_ehci_status("");
 
 	for (i = 1; i <= n_ports; i++) {
 		portsc = readl(&ehci_regs->port_status[i-1]);
@@ -523,138 +755,27 @@ try_next_port:
 		return -1;
 	}
 
-	loop = 250 * 1000;
-	/* Reset the EHCI controller */
-	cmd = readl(&ehci_regs->command);
-	cmd |= CMD_RESET;
-	writel(cmd, &ehci_regs->command);
-	do {
-		cmd = readl(&ehci_regs->command);
-	} while ((cmd & CMD_RESET) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("can not reset ehci\n");
-		return -1;
-	}
-	dbgp_printk("ehci reset done\n");
-
-	/* Claim ownership, but do not enable yet */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_OWNER;
-	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
-	writel(ctrl, &ehci_debug->control);
-	udelay(1);
-
-	/* Start the ehci running */
-	cmd = readl(&ehci_regs->command);
-	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
-	cmd |= CMD_RUN;
-	writel(cmd, &ehci_regs->command);
-
-	/* Ensure everything is routed to the EHCI */
-	writel(FLAG_CF, &ehci_regs->configured_flag);
-
-	/* Wait until the controller is no longer halted */
-	loop = 10;
-	do {
-		status = readl(&ehci_regs->status);
-		if (!(status & STS_HALT))
-			break;
-		udelay(1);
-	} while (--loop > 0);
-
-	if (!loop) {
-		dbgp_printk("ehci can not be started\n");
-		return -1;
+	/* Only reset the controller if it is not already in the
+	 * configured state */
+	if (!(readl(&ehci_regs->configured_flag) & FLAG_CF)) {
+		if (dbgp_ehci_controller_reset() != 0)
+			return -1;
+	} else {
+		dbgp_ehci_status("ehci skip - already configured");
 	}
-	dbgp_printk("ehci started\n");
 
-	/* Wait for a device to show up in the debug port */
-	ret = ehci_wait_for_port(debug_port);
-	if (ret < 0) {
-		dbgp_printk("No device found in debug port\n");
+	ret = dbgp_external_startup();
+	if (ret == -EIO)
 		goto next_debug_port;
-	}
-	dbgp_printk("ehci wait for port done\n");
-
-	/* Enable the debug port */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_CLAIM;
-	writel(ctrl, &ehci_debug->control);
-	ctrl = readl(&ehci_debug->control);
-	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
-		dbgp_printk("No device in debug port\n");
-		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
-		goto err;
-	}
-	dbgp_printk("debug ported enabled\n");
 
-	/* Completely transfer the debug device to the debug controller */
-	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
-	portsc &= ~PORT_PE;
-	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
-
-	dbgp_mdelay(100);
-
-	/* Find the debug device and make it device number 127 */
-	for (devnum = 0; devnum <= 127; devnum++) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
-			&dbgp_desc, sizeof(dbgp_desc));
-		if (ret > 0)
-			break;
-	}
-	if (devnum > 127) {
-		dbgp_printk("Could not find attached debug device\n");
-		goto err;
-	}
 	if (ret < 0) {
-		dbgp_printk("Attached device is not a debug device\n");
-		goto err;
-	}
-	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
-
-	/* Move the device to 127 if it isn't already there */
-	if (devnum != USB_DEBUG_DEVNUM) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
-		if (ret < 0) {
-			dbgp_printk("Could not move attached device to %d\n",
-				USB_DEBUG_DEVNUM);
-			goto err;
-		}
-		devnum = USB_DEBUG_DEVNUM;
-		dbgp_printk("debug device renamed to 127\n");
-	}
-
-	/* Enable the debug interface */
-	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
-		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
-	if (ret < 0) {
-		dbgp_printk(" Could not enable the debug device\n");
-		goto err;
-	}
-	dbgp_printk("debug interface enabled\n");
-
-	/* Perform a small write to get the even/odd data state in sync
-	 */
-	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
-	if (ret < 0) {
-		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
-		goto err;
+		/* Things didn't work so remove my claim */
+		ctrl = readl(&ehci_debug->control);
+		ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
+		writel(ctrl, &ehci_debug->control);
+		return -1;
 	}
-	dbgp_printk("small write doned\n");
-
 	return 0;
-err:
-	/* Things didn't work so remove my claim */
-	ctrl = readl(&ehci_debug->control);
-	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
-	writel(ctrl, &ehci_debug->control);
-	return -1;
 
 next_debug_port:
 	port_map_tried |= (1<<(debug_port - 1));
@@ -749,6 +870,7 @@ int __init early_dbgp_init(char *s)
 
 		return -1;
 	}
+	dbgp_ehci_status("early_init_complete");
 
 	return 0;
 }
@@ -758,9 +880,27 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n)
 	int chunk, ret;
 	char buf[DBGP_MAX_PACKET];
 	int use_cr = 0;
+	u32 cmd, ctrl;
+	int reset_run = 0;
 
-	if (!ehci_debug)
+	if (!ehci_debug || dbgp_not_safe)
 		return;
+
+	cmd = readl(&ehci_regs->command);
+	if (unlikely(!(cmd & CMD_RUN))) {
+		/* If the ehci controller is not in the run state do extended
+		 * checks to see if the acpi or some other initialization also
+		 * reset the ehci debug port */
+		ctrl = readl(&ehci_debug->control);
+		if (!(ctrl & DBGP_ENABLED)) {
+			dbgp_not_safe = 1;
+			dbgp_external_startup();
+		} else {
+			cmd |= CMD_RUN;
+			writel(cmd, &ehci_regs->command);
+			reset_run = 1;
+		}
+	}
 	while (n > 0) {
 		for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0;
 		     str++, chunk++, n--) {
@@ -775,8 +915,15 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n)
 				use_cr = 0;
 			buf[chunk] = *str;
 		}
-		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, buf, chunk);
+		if (chunk > 0) {
+			ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
+				      dbgp_endpoint_out, buf, chunk);
+		}
+	}
+	if (unlikely(reset_run)) {
+		cmd = readl(&ehci_regs->command);
+		cmd &= ~CMD_RUN;
+		writel(cmd, &ehci_regs->command);
 	}
 }
 
@@ -786,4 +933,3 @@ struct console early_dbgp_console = {
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };
-
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 0e22b5f..e1346fd 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -163,4 +163,9 @@ extern int __init early_dbgp_init(char *s);
 extern struct console early_dbgp_console;
 #endif /* CONFIG_EARLY_PRINTK_DBGP */
 
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+/* Call backs from ehci host driver to ehci debug driver */
+extern int dbgp_external_startup(void);
+#endif
+
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

[PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

If the EHCI debug port is initialized and in use, the EHCI host
controller driver must follow two rules.

1) If the EHCI host driver issues a controller reset, the debug
   controller driver re-initialization must get called after the reset
   is completed.

2) The EHCI host driver should ignore any requests to the physical
   EHCI debug port when the EHCI debug port is in use.

The code to check for debug port was moved from the ehci_pci_reinit()
to the EHCI host controller reset logic because it applies to any
condition where EHCI host controller is getting reset.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   23 +++++++++++++++++++++++
 drivers/usb/host/ehci-hcd.c   |   33 ++++++++++++++++++++++++++++++++-
 drivers/usb/host/ehci-hub.c   |   10 ++++++++++
 drivers/usb/host/ehci-pci.c   |   20 --------------------
 include/linux/usb/ehci_def.h  |    1 +
 5 files changed, 66 insertions(+), 21 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 06e05ea..b88cb65 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -933,3 +933,26 @@ struct console early_dbgp_console = {
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };
+
+int dbgp_reset_prep(void)
+{
+	u32 ctrl;
+
+	dbgp_not_safe = 1;
+	if (!ehci_debug)
+		return 0;
+
+	if (early_dbgp_console.index != -1 &&
+		!(early_dbgp_console.flags & CON_BOOT))
+		return 1;
+	/* This means the console is not initialized, or should get
+	 * shutdown so as to allow for reuse of the usb device, which
+	 * means it is time to shutdown the usb debug port. */
+	ctrl = readl(&ehci_debug->control);
+	if (ctrl & DBGP_ENABLED) {
+		ctrl &= ~(DBGP_CLAIM);
+		writel(ctrl, &ehci_debug->control);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dbgp_reset_prep);
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 7d03549..0d9cf9d 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -238,7 +238,33 @@ static int ehci_reset (struct ehci_hcd *ehci)
 {
 	int	retval;
 	u32	command = ehci_readl(ehci, &ehci->regs->command);
-
+	u32	temp;
+	struct pci_dev *pdev = to_pci_dev(ehci_to_hcd(ehci)->self.controller);
+
+	/* Special handling for the ehci debug port */
+	ehci->debug = NULL;
+	/* optional debug port, normally in the first BAR */
+	temp = pci_find_capability(pdev, 0x0a);
+	if (temp) {
+		pci_read_config_dword(pdev, temp, &temp);
+		temp >>= 16;
+		if ((temp & (3 << 13)) == (1 << 13)) {
+			temp &= 0xfff;
+			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
+			temp = ehci_readl(ehci, &ehci->debug->control);
+			ehci_info(ehci, "debug port %d%s\n",
+				  HCS_DEBUG_PORT(ehci->hcs_params),
+				  (temp & DBGP_ENABLED)
+				  ? " IN USE"
+				  : "");
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+			if (!dbgp_reset_prep() || !(temp & DBGP_ENABLED))
+#else
+			if (!(temp & DBGP_ENABLED))
+#endif
+				ehci->debug = NULL;
+		}
+	}
 	command |= CMD_RESET;
 	dbg_cmd (ehci, "reset", command);
 	ehci_writel(ehci, command, &ehci->regs->command);
@@ -253,6 +279,11 @@ static int ehci_reset (struct ehci_hcd *ehci)
 	if (ehci_is_TDI(ehci))
 		tdi_reset (ehci);
 
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+	/* Restore debug facilities if the controler was active */
+	if (ehci->debug)
+		dbgp_external_startup();
+#endif
 	return retval;
 }
 
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index f46ad27..149beb8 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -816,6 +816,15 @@ static int ehci_hub_control (
 	case SetPortFeature:
 		selector = wIndex >> 8;
 		wIndex &= 0xff;
+		if (unlikely(ehci->debug)) {
+			/* If the debug port is active any port
+			 * feature requests should get denied */
+			if ((readl(&ehci->debug->control) & DBGP_ENABLED) &&
+			    wIndex == HCS_DEBUG_PORT(ehci->hcs_params)) {
+				retval = -ENODEV;
+				goto error_exit;
+			}
+		}
 		if (!wIndex || wIndex > ports)
 			goto error;
 		wIndex--;
@@ -894,6 +903,7 @@ error:
 		/* "stall" on error */
 		retval = -EPIPE;
 	}
+error_exit:
 	spin_unlock_irqrestore (&ehci->lock, flags);
 	return retval;
 }
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index c2f1b7d..af73d12 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -27,28 +27,8 @@
 /* called after powerup, by probe or system-pm "wakeup" */
 static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev)
 {
-	u32			temp;
 	int			retval;
 
-	/* optional debug port, normally in the first BAR */
-	temp = pci_find_capability(pdev, 0x0a);
-	if (temp) {
-		pci_read_config_dword(pdev, temp, &temp);
-		temp >>= 16;
-		if ((temp & (3 << 13)) == (1 << 13)) {
-			temp &= 0x1fff;
-			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
-			temp = ehci_readl(ehci, &ehci->debug->control);
-			ehci_info(ehci, "debug port %d%s\n",
-				HCS_DEBUG_PORT(ehci->hcs_params),
-				(temp & DBGP_ENABLED)
-					? " IN USE"
-					: "");
-			if (!(temp & DBGP_ENABLED))
-				ehci->debug = NULL;
-		}
-	}
-
 	/* we expect static quirk code to handle the "extended capabilities"
 	 * (currently just BIOS handoff) allowed starting with EHCI 0.96
 	 */
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index e1346fd..279d48b 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -166,6 +166,7 @@ extern struct console early_dbgp_console;
 #ifdef CONFIG_EARLY_PRINTK_DBGP
 /* Call backs from ehci host driver to ehci debug driver */
 extern int dbgp_external_startup(void);
+extern int dbgp_reset_prep(void);
 #endif
 
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

[PATCH 08/10] ehci-dbgp: errata for EHCI debug controller initialization

[Jason Wessel]

On some EHCI usb debug controllers, the EHCI debug device will fail to
be seen after a port reset, after a warm reset.  Two options exist to
get the device to initialize correctly.

Option 1 is to unplug and plug in the device.

Option 2 is to use the EHCI port test to get the usb debug device to
start talking again.  At that point the debug controller port reset
will succeed.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
CC: dbrownell@users.sourceforge.net
---
 drivers/usb/early/ehci-dbgp.c |   23 ++++++++++++++++++++++-
 include/linux/usb/ehci_def.h  |    1 +
 2 files changed, 23 insertions(+), 1 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index b88cb65..f0a41c6 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -478,10 +478,13 @@ int dbgp_external_startup(void)
 	int devnum;
 	struct usb_debug_descriptor dbgp_desc;
 	int ret;
-	u32 ctrl, portsc;
+	u32 ctrl, portsc, cmd;
 	int dbg_port = dbgp_phys_port;
 	int tries = 3;
+	int reset_port_tries = 1;
+	int try_hard_once = 1;
 
+try_port_reset_again:
 	ret = dbgp_ehci_startup();
 	if (ret)
 		return ret;
@@ -490,6 +493,24 @@ int dbgp_external_startup(void)
 	ret = ehci_wait_for_port(dbg_port);
 	if (ret < 0) {
 		portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+		if (!(portsc & PORT_CONNECT) && try_hard_once) {
+			/* Last ditch effort to try to force enable
+			 * the debug device by using the packet test
+			 * ehci command to try and wake it up. */
+			try_hard_once = 0;
+			cmd = readl(&ehci_regs->command);
+			cmd &= ~CMD_RUN;
+			writel(cmd, &ehci_regs->command);
+			portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+			portsc |= PORT_TEST_PKT;
+			writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
+			dbgp_ehci_status("Trying to force debug port online");
+			mdelay(50);
+			dbgp_ehci_controller_reset();
+			goto try_port_reset_again;
+		} else if (reset_port_tries--) {
+			goto try_port_reset_again;
+		}
 		dbgp_printk("No device found in debug port\n");
 		return -EIO;
 	}
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 279d48b..209cf36 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -105,6 +105,7 @@ struct ehci_regs {
 #define PORT_WKDISC_E	(1<<21)		/* wake on disconnect (enable) */
 #define PORT_WKCONN_E	(1<<20)		/* wake on connect (enable) */
 /* 19:16 for port testing */
+#define PORT_TEST_PKT	(0x4<<16)	/* Port Test Control - packet test */
 #define PORT_LED_OFF	(0<<14)
 #define PORT_LED_AMBER	(1<<14)
 #define PORT_LED_GREEN	(2<<14)
-- 
1.6.0.3.523.g304d0

[PATCH 09/10] ehci-dbgp: errata for EHCI debug/host controller synchronization

[Jason Wessel]

On some EHCI debug controllers after the host controller driver is
activated, the debug controller will occasionally fail to submit a
bulk write URB.  On controllers that exhibit this behavior a dummy
bulk write must get submitted to resynchronize the device.

The "dummy bulk write" does not get received by the host attached to
the other end of the usb debug device.  The usb debug device simply
acknowledges the "dummy bulk write" and returns to a usable state.

The behavior, without this patch is that you see missing text from a
complete kernel boot when using the keep option to the earlyprintk
kernel argument.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   41 +++++++++++++++++++++++++++++------------
 1 files changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index f0a41c6..1206a26 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -245,16 +245,9 @@ static inline void dbgp_get_data(void *buf, int size)
 		bytes[i] = (hi >> (8*(i - 4))) & 0xff;
 }
 
-static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
-			 const char *bytes, int size)
+static int dbgp_out(u32 addr, const char *bytes, int size)
 {
-	u32 pids, addr, ctrl;
-	int ret;
-
-	if (size > DBGP_MAX_PACKET)
-		return -1;
-
-	addr = DBGP_EPADDR(devnum, endpoint);
+	u32 pids, ctrl;
 
 	pids = readl(&ehci_debug->pids);
 	pids = dbgp_pid_update(pids, USB_PID_OUT);
@@ -267,10 +260,34 @@ static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
 	dbgp_set_data(bytes, size);
 	writel(addr, &ehci_debug->address);
 	writel(pids, &ehci_debug->pids);
+	return dbgp_wait_until_done(ctrl);
+}
 
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
+static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
+			 const char *bytes, int size)
+{
+	int ret;
+	int loops = 5;
+	u32 addr;
+	if (size > DBGP_MAX_PACKET)
+		return -1;
+
+	addr = DBGP_EPADDR(devnum, endpoint);
+try_again:
+	if (loops--) {
+		ret = dbgp_out(addr, bytes, size);
+		if (ret == -DBGP_ERR_BAD) {
+			int try_loops = 3;
+			do {
+				/* Emit a dummy packet to re-sync communication
+				 * with the debug device */
+				if (dbgp_out(addr, "12345678", 8) >= 0) {
+					udelay(2);
+					goto try_again;
+				}
+			} while (try_loops--);
+		}
+	}
 
 	return ret;
 }
-- 
1.6.0.3.523.g304d0

[PATCH 10/10] ehci-dbgp,documentation: Documentation updates for ehci-dbgp

[Jason Wessel]

Add missing information about requirements of using the EHCI usb debug
controller as well as to mention you can use a debug controller other
than the first one in the system.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@intel.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
---
 Documentation/kernel-parameters.txt |    2 +-
 Documentation/x86/earlyprintk.txt   |   39 +++++++++++++++++++++++++++++++++-
 2 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd1a6d4..e709fc0 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -670,7 +670,7 @@ and is between 256 and 4096 characters. It is defined in the file
 	earlyprintk=	[X86,SH,BLACKFIN]
 			earlyprintk=vga
 			earlyprintk=serial[,ttySn[,baudrate]]
-			earlyprintk=dbgp
+			earlyprintk=dbgp[debugController#]
 
 			Append ",keep" to not disable it when the real console
 			takes over.
diff --git a/Documentation/x86/earlyprintk.txt b/Documentation/x86/earlyprintk.txt
index 607b1a0..f19802c 100644
--- a/Documentation/x86/earlyprintk.txt
+++ b/Documentation/x86/earlyprintk.txt
@@ -7,7 +7,7 @@ and two USB cables, connected like this:
 
   [host/target] <-------> [USB debug key] <-------> [client/console]
 
-1. There are three specific hardware requirements:
+1. There are a number of specific hardware requirements:
 
  a.) Host/target system needs to have USB debug port capability.
 
@@ -42,7 +42,35 @@ and two USB cables, connected like this:
      This is a small blue plastic connector with two USB connections,
      it draws power from its USB connections.
 
- c.) Thirdly, you need a second client/console system with a regular USB port.
+ c.) You need a second client/console system with a high speed USB 2.0
+     port.
+
+ d.) The Netchip device must be plugged directly into the physical
+     debug port on the "host/target" system.  You cannot use a USB hub in
+     between the physical debug port and the "host/target" system.
+
+     The EHCI debug controller is bound to a specific physical USB
+     port and the Netchip device will only work as an early printk
+     device in this port.  The EHCI host controllers are electrically
+     wired such that the EHCI debug controller is hooked up to the
+     first physical and there is no way to change this via software.
+     You can find the physical port through experimentation by trying
+     each physical port on the system and rebooting.  Or you can try
+     and use lsusb or look at the kernel info messages emitted by the
+     usb stack when you plug a usb device into various ports on the
+     "host/target" system.
+
+     Some hardware vendors do not expose the usb debug port with a
+     physical connector and if you find such a device send a complaint
+     to the hardware vendor, because there is no reason not to wire
+     this port into one of the physically accessible ports.
+
+ e.) It is also important to note, that many versions of the Netchip
+     device require the "client/console" system to be plugged into the
+     right and side of the device (with the product logo facing up and
+     readable left to right).  The reason being is that the 5 volt
+     power supply is taken from only one side of the device and it
+     must be the side that does not get rebooted.
 
 2. Software requirements:
 
@@ -56,6 +84,13 @@ and two USB cables, connected like this:
     (If you are using Grub, append it to the 'kernel' line in
      /etc/grub.conf)
 
+    On systems with more than one EHCI debug controller you must
+    specify the correct EHCI debug controller number.  The ordering
+    comes from the PCI bus enumeration of the EHCI controllers.  The
+    default with no number argument is "0" the first EHCI debug
+    controller.  To use the second EHCI debug controller, you would
+    use the command line: "earlyprintk=dbgp1"
+
     NOTE: normally earlyprintk console gets turned off once the
     regular console is alive - use "earlyprintk=dbgp,keep" to keep
     this channel open beyond early bootup. This can be useful for
-- 
1.6.0.3.523.g304d0

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Alan Stern]

On Mon, 20 Jul 2009, Jason Wessel wrote:

> If the EHCI debug port is initialized and in use, the EHCI host
> controller driver must follow two rules.
> 
> 1) If the EHCI host driver issues a controller reset, the debug
>    controller driver re-initialization must get called after the reset
>    is completed.
> 
> 2) The EHCI host driver should ignore any requests to the physical
>    EHCI debug port when the EHCI debug port is in use.
> 
> The code to check for debug port was moved from the ehci_pci_reinit()
> to the EHCI host controller reset logic because it applies to any
> condition where EHCI host controller is getting reset.

> --- a/drivers/usb/host/ehci-hcd.c
> +++ b/drivers/usb/host/ehci-hcd.c
> @@ -238,7 +238,33 @@ static int ehci_reset (struct ehci_hcd *ehci)
>  {
>  	int	retval;
>  	u32	command = ehci_readl(ehci, &ehci->regs->command);
> -
> +	u32	temp;
> +	struct pci_dev *pdev = to_pci_dev(ehci_to_hcd(ehci)->self.controller);
> +
> +	/* Special handling for the ehci debug port */
> +	ehci->debug = NULL;
> +	/* optional debug port, normally in the first BAR */
> +	temp = pci_find_capability(pdev, 0x0a);

This isn't going to work very well on systems with non-PCI EHCI
controllers.  Maybe you should leave debug-port detection in
ehci-pci.c.  The controller doesn't get reset very much in any case.

> +	if (temp) {
> +		pci_read_config_dword(pdev, temp, &temp);
> +		temp >>= 16;
> +		if ((temp & (3 << 13)) == (1 << 13)) {
> +			temp &= 0xfff;
> +			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
> +			temp = ehci_readl(ehci, &ehci->debug->control);
> +			ehci_info(ehci, "debug port %d%s\n",
> +				  HCS_DEBUG_PORT(ehci->hcs_params),
> +				  (temp & DBGP_ENABLED)
> +				  ? " IN USE"
> +				  : "");
> +#ifdef CONFIG_EARLY_PRINTK_DBGP
> +			if (!dbgp_reset_prep() || !(temp & DBGP_ENABLED))
> +#else
> +			if (!(temp & DBGP_ENABLED))
> +#endif

This sort of thing is better handled by defining dhbp_reset_prep() as 
an inline routine or macro always returning 1 if 
CONFIG_EARLY_PRINTK_DBGP isn't set.

> @@ -253,6 +279,11 @@ static int ehci_reset (struct ehci_hcd *ehci)
>  	if (ehci_is_TDI(ehci))
>  		tdi_reset (ehci);
>  
> +#ifdef CONFIG_EARLY_PRINTK_DBGP
> +	/* Restore debug facilities if the controler was active */
> +	if (ehci->debug)
> +		dbgp_external_startup();
> +#endif

Similarly here, make dgbp_external_startup() an empty inline function 
or an empty macro.

Alan Stern

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

Alan Stern wrote:
> On Mon, 20 Jul 2009, Jason Wessel wrote:
>> +    /* optional debug port, normally in the first BAR */
>> +    temp = pci_find_capability(pdev, 0x0a);
>
> This isn't going to work very well on systems with non-PCI EHCI
> controllers.  Maybe you should leave debug-port detection in
> ehci-pci.c.  The controller doesn't get reset very much in any case.
>

I'll take a deeper look as to why it didn't work correctly where the
code was originally sitting.  It had something to do with the reset
clearing the debug controller settings.

This chunk got moved prior to creating the reset_prep logic, so in all
likely hood it should go back to where it was, because we do want this
to work with the pci and non-pci case.

>> +            if (!dbgp_reset_prep() || !(temp & DBGP_ENABLED))
>
> This sort of thing is better handled by defining dhbp_reset_prep() as
> an inline routine or macro always returning 1 if
> CONFIG_EARLY_PRINTK_DBGP isn't set.
>
>> +        dbgp_external_startup();
>
> Similarly here, make dgbp_external_startup() an empty inline function
> or an empty macro.
>

Sure, I'll fix these for a round #2 after any other comments come back.

Thanks for the comments,
Jason.

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

Alan Stern wrote:
> On Mon, 20 Jul 2009, Jason Wessel wrote:
>> +    /* optional debug port, normally in the first BAR */
>> +    temp = pci_find_capability(pdev, 0x0a);
> This isn't going to work very well on systems with non-PCI EHCI
> controllers.  Maybe you should leave debug-port detection in
> ehci-pci.c.  The controller doesn't get reset very much in any case.
>
 

The high level debug port detection still needed to move, but you are
correct, it needs to move with in the ehci-pci.c.

The ehci_reset() definitely clears the debug controller in the pci
probe call to ehci_pci_setup().  The debug port detect code just needs
to get called before the ehci_reset() in this case.

The repaired patch is inline below.

Thanks,
Jason.

---
From: Jason Wessel <jason.wessel@windriver.com>
Subject: [PATCH] ehci-dbgp,ehci: Allow early or late use of the dbgp device

If the EHCI debug port is initialized and in use, the EHCI host
controller driver must follow two rules.

1) If the EHCI host driver issues a controller reset, the debug
   controller driver re-initialization must get called after the reset
   is completed.

2) The EHCI host driver should ignore any requests to the physical
   EHCI debug port when the EHCI debug port is in use.

The code to check for the debug port was moved from ehci_pci_reinit()
to ehci_pci_setup because it must get called prior to ehci_reset()
which will clear the debug port registers.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

---
 drivers/usb/early/ehci-dbgp.c |   23 +++++++++++++++++++++++
 drivers/usb/host/ehci-hcd.c   |    8 ++++++++
 drivers/usb/host/ehci-hub.c   |   10 ++++++++++
 drivers/usb/host/ehci-pci.c   |   39 +++++++++++++++++++--------------------
 include/linux/usb/ehci_def.h  |   10 ++++++++++
 5 files changed, 70 insertions(+), 20 deletions(-)

--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -239,6 +239,11 @@ static int ehci_reset (struct ehci_hcd *
 	int	retval;
 	u32	command = ehci_readl(ehci, &ehci->regs->command);
 
+	/* If the EHCI debug controller is active, special care must be
+	 * taken before and after a host controller reset */
+	if (ehci->debug && !dbgp_reset_prep())
+		ehci->debug = NULL;
+
 	command |= CMD_RESET;
 	dbg_cmd (ehci, "reset", command);
 	ehci_writel(ehci, command, &ehci->regs->command);
@@ -253,6 +258,9 @@ static int ehci_reset (struct ehci_hcd *
 	if (ehci_is_TDI(ehci))
 		tdi_reset (ehci);
 
+	if (ehci->debug)
+		dbgp_external_startup();
+
 	return retval;
 }
 
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -816,6 +816,15 @@ static int ehci_hub_control (
 	case SetPortFeature:
 		selector = wIndex >> 8;
 		wIndex &= 0xff;
+		if (unlikely(ehci->debug)) {
+			/* If the debug port is active any port
+			 * feature requests should get denied */
+			if ((readl(&ehci->debug->control) & DBGP_ENABLED) &&
+			    wIndex == HCS_DEBUG_PORT(ehci->hcs_params)) {
+				retval = -ENODEV;
+				goto error_exit;
+			}
+		}
 		if (!wIndex || wIndex > ports)
 			goto error;
 		wIndex--;
@@ -894,6 +903,7 @@ error:
 		/* "stall" on error */
 		retval = -EPIPE;
 	}
+error_exit:
 	spin_unlock_irqrestore (&ehci->lock, flags);
 	return retval;
 }
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -27,28 +27,8 @@
 /* called after powerup, by probe or system-pm "wakeup" */
 static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev)
 {
-	u32			temp;
 	int			retval;
 
-	/* optional debug port, normally in the first BAR */
-	temp = pci_find_capability(pdev, 0x0a);
-	if (temp) {
-		pci_read_config_dword(pdev, temp, &temp);
-		temp >>= 16;
-		if ((temp & (3 << 13)) == (1 << 13)) {
-			temp &= 0x1fff;
-			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
-			temp = ehci_readl(ehci, &ehci->debug->control);
-			ehci_info(ehci, "debug port %d%s\n",
-				HCS_DEBUG_PORT(ehci->hcs_params),
-				(temp & DBGP_ENABLED)
-					? " IN USE"
-					: "");
-			if (!(temp & DBGP_ENABLED))
-				ehci->debug = NULL;
-		}
-	}
-
 	/* we expect static quirk code to handle the "extended capabilities"
 	 * (currently just BIOS handoff) allowed starting with EHCI 0.96
 	 */
@@ -192,6 +172,25 @@ static int ehci_pci_setup(struct usb_hcd
 		break;
 	}
 
+	/* optional debug port, normally in the first BAR */
+	temp = pci_find_capability(pdev, 0x0a);
+	if (temp) {
+		pci_read_config_dword(pdev, temp, &temp);
+		temp >>= 16;
+		if ((temp & (3 << 13)) == (1 << 13)) {
+			temp &= 0x1fff;
+			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
+			temp = ehci_readl(ehci, &ehci->debug->control);
+			ehci_info(ehci, "debug port %d%s\n",
+				HCS_DEBUG_PORT(ehci->hcs_params),
+				(temp & DBGP_ENABLED)
+					? " IN USE"
+					: "");
+			if (!(temp & DBGP_ENABLED))
+				ehci->debug = NULL;
+		}
+	}
+
 	ehci_reset(ehci);
 
 	/* at least the Genesys GL880S needs fixup here */
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -971,3 +971,26 @@ struct console early_dbgp_console = {
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };
+
+int dbgp_reset_prep(void)
+{
+	u32 ctrl;
+
+	dbgp_not_safe = 1;
+	if (!ehci_debug)
+		return 0;
+
+	if (early_dbgp_console.index != -1 &&
+		!(early_dbgp_console.flags & CON_BOOT))
+		return 1;
+	/* This means the console is not initialized, or should get
+	 * shutdown so as to allow for reuse of the usb device, which
+	 * means it is time to shutdown the usb debug port. */
+	ctrl = readl(&ehci_debug->control);
+	if (ctrl & DBGP_ENABLED) {
+		ctrl &= ~(DBGP_CLAIM);
+		writel(ctrl, &ehci_debug->control);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dbgp_reset_prep);
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -167,6 +167,16 @@ extern struct console early_dbgp_console
 #ifdef CONFIG_EARLY_PRINTK_DBGP
 /* Call backs from ehci host driver to ehci debug driver */
 extern int dbgp_external_startup(void);
+extern int dbgp_reset_prep(void);
+#else
+static inline int dbgp_reset_prep(void)
+{
+	return 1;
+}
+static inline int dbgp_external_startup(void)
+{
+	return -1;
+}
 #endif
 
 #endif /* __LINUX_USB_EHCI_DEF_H */

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Alan Stern]

On Tue, 21 Jul 2009, Jason Wessel wrote:

> Alan Stern wrote:
> > On Mon, 20 Jul 2009, Jason Wessel wrote:
> >> +    /* optional debug port, normally in the first BAR */
> >> +    temp = pci_find_capability(pdev, 0x0a);
> > This isn't going to work very well on systems with non-PCI EHCI
> > controllers.  Maybe you should leave debug-port detection in
> > ehci-pci.c.  The controller doesn't get reset very much in any case.
> >
>  
> 
> The high level debug port detection still needed to move, but you are
> correct, it needs to move with in the ehci-pci.c.
> 
> The ehci_reset() definitely clears the debug controller in the pci
> probe call to ehci_pci_setup().  The debug port detect code just needs
> to get called before the ehci_reset() in this case.
> 
> The repaired patch is inline below.

This is much better.

Alan Stern

Re: [PATCH 01/10] ehci early_printk: split ehci debug driver from early_printk.c

[Yinghai Lu]

Jason Wessel wrote:
> Move the dbgp early printk driver in advance of refactoring and adding
> new code, so the changes to this code are tracked separately from the
> move of the code.
> 
> The drivers/usb/early directory will be the location of the current
> and future early usb code for driving usb devices prior initializing
> the standard interrupt driven USB drivers.
> 
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> Cc: Greg KH <gregkh@suse.de>
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Yinghai Lu <yinghai@kernel.org>
> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/x86/kernel/early_printk.c |  715 ---------------------------------------
>  drivers/usb/Makefile           |    1 +
>  drivers/usb/early/Makefile     |    5 +
>  drivers/usb/early/ehci-dbgp.c  |  723 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/usb/ehci_def.h   |    6 +
>  5 files changed, 735 insertions(+), 715 deletions(-)
>  create mode 100644 drivers/usb/early/Makefile
>  create mode 100644 drivers/usb/early/ehci-dbgp.c

before this patch, we could use dbgp without compiling USB susbsystem in...

YH

Re: [PATCH 01/10] ehci early_printk: split ehci debug driver from early_printk.c

[Jason Wessel]

Yinghai Lu wrote:
> Jason Wessel wrote:
>   
>> Move the dbgp early printk driver in advance of refactoring and adding
>> new code, so the changes to this code are tracked separately from the
>> move of the code.
>>
>> The drivers/usb/early directory will be the location of the current
>> and future early usb code for driving usb devices prior initializing
>> the standard interrupt driven USB drivers.
>>
>> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
>> Cc: Greg KH <gregkh@suse.de>
>> Cc: Ingo Molnar <mingo@elte.hu>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Yinghai Lu <yinghai@kernel.org>
>> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
>> ---
>>  arch/x86/kernel/early_printk.c |  715 ---------------------------------------
>>  drivers/usb/Makefile           |    1 +
>>  drivers/usb/early/Makefile     |    5 +
>>  drivers/usb/early/ehci-dbgp.c  |  723 ++++++++++++++++++++++++++++++++++++++++
>>  include/linux/usb/ehci_def.h   |    6 +
>>  5 files changed, 735 insertions(+), 715 deletions(-)
>>  create mode 100644 drivers/usb/early/Makefile
>>  create mode 100644 drivers/usb/early/ehci-dbgp.c
>>     
>
> before this patch, we could use dbgp without compiling USB susbsystem in...
>
>   

And you shouldn't need it today.  You pointed out an error in the patch
which I will correct.  The drivers/Makefile needs to be changed, instead
of the drivers/usb/Makefile.

The dbgp code was changed in the patch series such that it works with or
with out the usb subsystem and with or without the earlyconsole=keep,...

All the code in the drivers/usb/early would work this way as well.  As
an example, I have an experimental UHCI serial driver that can be used
via the earlyprintk.

Thanks for the feed back.  I'll fix this for the v2 of the patch series.
Jason.

Re: [PATCH 01/10] ehci early_printk: split ehci debug driver from early_printk.c

[Jason Wessel]

Jason Wessel wrote:
> Yinghai Lu wrote:
>   
>> Jason Wessel wrote:
>>   
>>     
>>> Move the dbgp early printk driver in advance of refactoring and adding
>>> new code, so the changes to this code are tracked separately from the
>>> move of the code.
>>>
>>> The drivers/usb/early directory will be the location of the current
>>> and future early usb code for driving usb devices prior initializing
>>> the standard interrupt driven USB drivers.
>>>
>>> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
>>> Cc: Greg KH <gregkh@suse.de>
>>> Cc: Ingo Molnar <mingo@elte.hu>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> Cc: Yinghai Lu <yinghai@kernel.org>
>>> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
>>> ---
>>>  arch/x86/kernel/early_printk.c |  715 ---------------------------------------
>>>  drivers/usb/Makefile           |    1 +
>>>  drivers/usb/early/Makefile     |    5 +
>>>  drivers/usb/early/ehci-dbgp.c  |  723 ++++++++++++++++++++++++++++++++++++++++
>>>  include/linux/usb/ehci_def.h   |    6 +
>>>  5 files changed, 735 insertions(+), 715 deletions(-)
>>>  create mode 100644 drivers/usb/early/Makefile
>>>  create mode 100644 drivers/usb/early/ehci-dbgp.c
>>>     
>>>       
>> before this patch, we could use dbgp without compiling USB susbsystem in...
>>
>>   
>>     
>
> And you shouldn't need it today.  You pointed out an error in the patch
> which I will correct.  The drivers/Makefile needs to be changed, instead
> of the drivers/usb/Makefile.
>
> The dbgp code was changed in the patch series such that it works with or
> with out the usb subsystem and with or without the earlyconsole=keep,...
>
> All the code in the drivers/usb/early would work this way as well.  As
> an example, I have an experimental UHCI serial driver that can be used
> via the earlyprintk.
>
>
>   
So I checked into this further because I was curious how all the tests
passed. 

The drivers/usb/Makefile is read because of the line in drivers/Makefile

     67 obj-$(CONFIG_PCI)               += usb/

That of course will cause the drivers/usb/early/Makefile to get read. 
This explains why all the testing passed.  For now it might be ok, but
it will have to get changed to compile the dbgp driver when/if the dbgp
gets changed to work with a non-pci EHCI controller.

Jason.

[PATCH 0/10] x86: EHCI and earlyprintk= improvements (Round 2)

[Jason Wessel]

Greg KH requested a re-post of this patch series, so here is round 2.
The only implementation change here was in patch 7 of 10 per comments
from Alan Stern.  The rest is just context changes from the typical
kernel churn.

--

This patch series against the 2.6.31-rc3 covers improving the
reliability of earlyprintk when using a usb debug device connected to
an EHCI debug controller.

The only patch that is not directly related to the USB earlyprintk is
the 5th in the series which changes the console registration such that
you can have more than one earlyprintk device.  It is plausible to
drop this patch if folks object to the idea or implementation.

These patches were heavily test on 12 different systems with a total
of 7 different EHCI controllers on both the x86_64 and i386
architectures.

The series starts by moving the EHCI debug code out of the
arch/x86/kernel/early_printk.c and over to under the
drivers/usb/early/ehci-dbgp.c.  It is plausible to use this code on
other architectures beyond x86.  This also allows the earlyprintk.c to
stay a bit cleaner, since it is primarily intended to handle the
"earlyprintk=" setup.

The other key changes are:
   * Update the documentation to reflect the usage constraints
   * The earlyprintk=keep,... works correctly with dbgp
   * Make the cr nl handling for dbgp the same as the uart drivers
   * Numerous errata and initialization fixes to make the usb
     debug device work with a wide range of EHCI controllers

Thanks,
Jason.

The following changes since commit b592972493c38665efd7d429a01b23fcb21e331a:
  Linus Torvalds (1):
        Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/.../tip/l
inux-2.6-tip

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.git for_gregkh_2

Jason Wessel (10):
      ehci early_printk: split ehci debug driver from early_printk.c
      usb,early_printk: insert cr prior to nl as needed
      ehci-dbgp: Execute early BIOS hand off
      usb,early_printk: EHCI debug controller initialization delays
      printk,early_printk,console: Allow more than one early console
      ehci-dbgp: stability improvements and external re-init
      ehci-dbgp,ehci: Allow early or late use of the dbgp device
      ehci-dbgp: errata for EHCI debug controller initialization
      ehci-dbgp: errata for EHCI debug/host controller synchronization
      ehci-dbgp,documentation: Documentation updates for ehci-dbgp

 Documentation/kernel-parameters.txt |    2 +-
 Documentation/x86/earlyprintk.txt   |   39 ++-
 arch/x86/kernel/early_printk.c      |  780 ++--------------------------
 drivers/usb/Makefile                |    1 +
 drivers/usb/early/Makefile          |    5 +
 drivers/usb/early/ehci-dbgp.c       |  996 +++++++++++++++++++++++++++++++++++
 drivers/usb/host/ehci-hcd.c         |    8 +
 drivers/usb/host/ehci-hub.c         |   10 +
 drivers/usb/host/ehci-pci.c         |   39 +-
 include/linux/usb/ehci_def.h        |   22 +
 kernel/printk.c                     |   41 +-
 11 files changed, 1158 insertions(+), 785 deletions(-)
 create mode 100644 drivers/usb/early/Makefile
 create mode 100644 drivers/usb/early/ehci-dbgp.c

[PATCH 01/10] ehci early_printk: split ehci debug driver from early_printk.c

[Jason Wessel]

Move the dbgp early printk driver in advance of refactoring and adding
new code, so the changes to this code are tracked separately from the
move of the code.

The drivers/usb/early directory will be the location of the current
and future early usb code for driving usb devices prior initializing
the standard interrupt driven USB drivers.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/x86/kernel/early_printk.c |  715 ---------------------------------------
 drivers/usb/Makefile           |    1 +
 drivers/usb/early/Makefile     |    5 +
 drivers/usb/early/ehci-dbgp.c  |  723 ++++++++++++++++++++++++++++++++++++++++
 include/linux/usb/ehci_def.h   |    6 +
 5 files changed, 735 insertions(+), 715 deletions(-)
 create mode 100644 drivers/usb/early/Makefile
 create mode 100644 drivers/usb/early/ehci-dbgp.c

diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index 335f049..519a5e1 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -160,721 +160,6 @@ static struct console early_serial_console = {
 	.index =	-1,
 };
 
-#ifdef CONFIG_EARLY_PRINTK_DBGP
-
-static struct ehci_caps __iomem *ehci_caps;
-static struct ehci_regs __iomem *ehci_regs;
-static struct ehci_dbg_port __iomem *ehci_debug;
-static unsigned int dbgp_endpoint_out;
-
-struct ehci_dev {
-	u32 bus;
-	u32 slot;
-	u32 func;
-};
-
-static struct ehci_dev ehci_dev;
-
-#define USB_DEBUG_DEVNUM 127
-
-#define DBGP_DATA_TOGGLE	0x8800
-
-static inline u32 dbgp_pid_update(u32 x, u32 tok)
-{
-	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
-}
-
-static inline u32 dbgp_len_update(u32 x, u32 len)
-{
-	return (x & ~0x0f) | (len & 0x0f);
-}
-
-/*
- * USB Packet IDs (PIDs)
- */
-
-/* token */
-#define USB_PID_OUT		0xe1
-#define USB_PID_IN		0x69
-#define USB_PID_SOF		0xa5
-#define USB_PID_SETUP		0x2d
-/* handshake */
-#define USB_PID_ACK		0xd2
-#define USB_PID_NAK		0x5a
-#define USB_PID_STALL		0x1e
-#define USB_PID_NYET		0x96
-/* data */
-#define USB_PID_DATA0		0xc3
-#define USB_PID_DATA1		0x4b
-#define USB_PID_DATA2		0x87
-#define USB_PID_MDATA		0x0f
-/* Special */
-#define USB_PID_PREAMBLE	0x3c
-#define USB_PID_ERR		0x3c
-#define USB_PID_SPLIT		0x78
-#define USB_PID_PING		0xb4
-#define USB_PID_UNDEF_0		0xf0
-
-#define USB_PID_DATA_TOGGLE	0x88
-#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
-
-#define PCI_CAP_ID_EHCI_DEBUG	0xa
-
-#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
-#define HUB_SHORT_RESET_TIME	10
-#define HUB_LONG_RESET_TIME	200
-#define HUB_RESET_TIMEOUT	500
-
-#define DBGP_MAX_PACKET		8
-
-static int dbgp_wait_until_complete(void)
-{
-	u32 ctrl;
-	int loop = 0x100000;
-
-	do {
-		ctrl = readl(&ehci_debug->control);
-		/* Stop when the transaction is finished */
-		if (ctrl & DBGP_DONE)
-			break;
-	} while (--loop > 0);
-
-	if (!loop)
-		return -1;
-
-	/*
-	 * Now that we have observed the completed transaction,
-	 * clear the done bit.
-	 */
-	writel(ctrl | DBGP_DONE, &ehci_debug->control);
-	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
-}
-
-static void __init dbgp_mdelay(int ms)
-{
-	int i;
-
-	while (ms--) {
-		for (i = 0; i < 1000; i++)
-			outb(0x1, 0x80);
-	}
-}
-
-static void dbgp_breath(void)
-{
-	/* Sleep to give the debug port a chance to breathe */
-}
-
-static int dbgp_wait_until_done(unsigned ctrl)
-{
-	u32 pids, lpid;
-	int ret;
-	int loop = 3;
-
-retry:
-	writel(ctrl | DBGP_GO, &ehci_debug->control);
-	ret = dbgp_wait_until_complete();
-	pids = readl(&ehci_debug->pids);
-	lpid = DBGP_PID_GET(pids);
-
-	if (ret < 0)
-		return ret;
-
-	/*
-	 * If the port is getting full or it has dropped data
-	 * start pacing ourselves, not necessary but it's friendly.
-	 */
-	if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET))
-		dbgp_breath();
-
-	/* If I get a NACK reissue the transmission */
-	if (lpid == USB_PID_NAK) {
-		if (--loop > 0)
-			goto retry;
-	}
-
-	return ret;
-}
-
-static void dbgp_set_data(const void *buf, int size)
-{
-	const unsigned char *bytes = buf;
-	u32 lo, hi;
-	int i;
-
-	lo = hi = 0;
-	for (i = 0; i < 4 && i < size; i++)
-		lo |= bytes[i] << (8*i);
-	for (; i < 8 && i < size; i++)
-		hi |= bytes[i] << (8*(i - 4));
-	writel(lo, &ehci_debug->data03);
-	writel(hi, &ehci_debug->data47);
-}
-
-static void __init dbgp_get_data(void *buf, int size)
-{
-	unsigned char *bytes = buf;
-	u32 lo, hi;
-	int i;
-
-	lo = readl(&ehci_debug->data03);
-	hi = readl(&ehci_debug->data47);
-	for (i = 0; i < 4 && i < size; i++)
-		bytes[i] = (lo >> (8*i)) & 0xff;
-	for (; i < 8 && i < size; i++)
-		bytes[i] = (hi >> (8*(i - 4))) & 0xff;
-}
-
-static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
-			 const char *bytes, int size)
-{
-	u32 pids, addr, ctrl;
-	int ret;
-
-	if (size > DBGP_MAX_PACKET)
-		return -1;
-
-	addr = DBGP_EPADDR(devnum, endpoint);
-
-	pids = readl(&ehci_debug->pids);
-	pids = dbgp_pid_update(pids, USB_PID_OUT);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, size);
-	ctrl |= DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	dbgp_set_data(bytes, size);
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	return ret;
-}
-
-static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
-				 int size)
-{
-	u32 pids, addr, ctrl;
-	int ret;
-
-	if (size > DBGP_MAX_PACKET)
-		return -1;
-
-	addr = DBGP_EPADDR(devnum, endpoint);
-
-	pids = readl(&ehci_debug->pids);
-	pids = dbgp_pid_update(pids, USB_PID_IN);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, size);
-	ctrl &= ~DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	if (size > ret)
-		size = ret;
-	dbgp_get_data(data, size);
-	return ret;
-}
-
-static int __init dbgp_control_msg(unsigned devnum, int requesttype,
-	int request, int value, int index, void *data, int size)
-{
-	u32 pids, addr, ctrl;
-	struct usb_ctrlrequest req;
-	int read;
-	int ret;
-
-	read = (requesttype & USB_DIR_IN) != 0;
-	if (size > (read ? DBGP_MAX_PACKET:0))
-		return -1;
-
-	/* Compute the control message */
-	req.bRequestType = requesttype;
-	req.bRequest = request;
-	req.wValue = cpu_to_le16(value);
-	req.wIndex = cpu_to_le16(index);
-	req.wLength = cpu_to_le16(size);
-
-	pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
-	addr = DBGP_EPADDR(devnum, 0);
-
-	ctrl = readl(&ehci_debug->control);
-	ctrl = dbgp_len_update(ctrl, sizeof(req));
-	ctrl |= DBGP_OUT;
-	ctrl |= DBGP_GO;
-
-	/* Send the setup message */
-	dbgp_set_data(&req, sizeof(req));
-	writel(addr, &ehci_debug->address);
-	writel(pids, &ehci_debug->pids);
-	ret = dbgp_wait_until_done(ctrl);
-	if (ret < 0)
-		return ret;
-
-	/* Read the result */
-	return dbgp_bulk_read(devnum, 0, data, size);
-}
-
-
-/* Find a PCI capability */
-static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap)
-{
-	u8 pos;
-	int bytes;
-
-	if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
-		PCI_STATUS_CAP_LIST))
-		return 0;
-
-	pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
-	for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
-		u8 id;
-
-		pos &= ~3;
-		id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
-		if (id == 0xff)
-			break;
-		if (id == cap)
-			return pos;
-
-		pos = read_pci_config_byte(num, slot, func,
-						 pos+PCI_CAP_LIST_NEXT);
-	}
-	return 0;
-}
-
-static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func)
-{
-	u32 class;
-
-	class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
-	if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI)
-		return 0;
-
-	return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
-}
-
-static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
-{
-	u32 bus, slot, func;
-
-	for (bus = 0; bus < 256; bus++) {
-		for (slot = 0; slot < 32; slot++) {
-			for (func = 0; func < 8; func++) {
-				unsigned cap;
-
-				cap = __find_dbgp(bus, slot, func);
-
-				if (!cap)
-					continue;
-				if (ehci_num-- != 0)
-					continue;
-				*rbus = bus;
-				*rslot = slot;
-				*rfunc = func;
-				return cap;
-			}
-		}
-	}
-	return 0;
-}
-
-static int __init ehci_reset_port(int port)
-{
-	u32 portsc;
-	u32 delay_time, delay;
-	int loop;
-
-	/* Reset the usb debug port */
-	portsc = readl(&ehci_regs->port_status[port - 1]);
-	portsc &= ~PORT_PE;
-	portsc |= PORT_RESET;
-	writel(portsc, &ehci_regs->port_status[port - 1]);
-
-	delay = HUB_ROOT_RESET_TIME;
-	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
-	     delay_time += delay) {
-		dbgp_mdelay(delay);
-
-		portsc = readl(&ehci_regs->port_status[port - 1]);
-		if (portsc & PORT_RESET) {
-			/* force reset to complete */
-			loop = 2;
-			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
-				&ehci_regs->port_status[port - 1]);
-			do {
-				portsc = readl(&ehci_regs->port_status[port-1]);
-			} while ((portsc & PORT_RESET) && (--loop > 0));
-		}
-
-		/* Device went away? */
-		if (!(portsc & PORT_CONNECT))
-			return -ENOTCONN;
-
-		/* bomb out completely if something weird happend */
-		if ((portsc & PORT_CSC))
-			return -EINVAL;
-
-		/* If we've finished resetting, then break out of the loop */
-		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
-			return 0;
-	}
-	return -EBUSY;
-}
-
-static int __init ehci_wait_for_port(int port)
-{
-	u32 status;
-	int ret, reps;
-
-	for (reps = 0; reps < 3; reps++) {
-		dbgp_mdelay(100);
-		status = readl(&ehci_regs->status);
-		if (status & STS_PCD) {
-			ret = ehci_reset_port(port);
-			if (ret == 0)
-				return 0;
-		}
-	}
-	return -ENOTCONN;
-}
-
-#ifdef DBGP_DEBUG
-# define dbgp_printk early_printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
-
-typedef void (*set_debug_port_t)(int port);
-
-static void __init default_set_debug_port(int port)
-{
-}
-
-static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
-
-static void __init nvidia_set_debug_port(int port)
-{
-	u32 dword;
-	dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
-				 0x74);
-	dword &= ~(0x0f<<12);
-	dword |= ((port & 0x0f)<<12);
-	write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74,
-				 dword);
-	dbgp_printk("set debug port to %d\n", port);
-}
-
-static void __init detect_set_debug_port(void)
-{
-	u32 vendorid;
-
-	vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
-		 0x00);
-
-	if ((vendorid & 0xffff) == 0x10de) {
-		dbgp_printk("using nvidia set_debug_port\n");
-		set_debug_port = nvidia_set_debug_port;
-	}
-}
-
-static int __init ehci_setup(void)
-{
-	struct usb_debug_descriptor dbgp_desc;
-	u32 cmd, ctrl, status, portsc, hcs_params;
-	u32 debug_port, new_debug_port = 0, n_ports;
-	u32  devnum;
-	int ret, i;
-	int loop;
-	int port_map_tried;
-	int playtimes = 3;
-
-try_next_time:
-	port_map_tried = 0;
-
-try_next_port:
-
-	hcs_params = readl(&ehci_caps->hcs_params);
-	debug_port = HCS_DEBUG_PORT(hcs_params);
-	n_ports    = HCS_N_PORTS(hcs_params);
-
-	dbgp_printk("debug_port: %d\n", debug_port);
-	dbgp_printk("n_ports:    %d\n", n_ports);
-
-	for (i = 1; i <= n_ports; i++) {
-		portsc = readl(&ehci_regs->port_status[i-1]);
-		dbgp_printk("portstatus%d: %08x\n", i, portsc);
-	}
-
-	if (port_map_tried && (new_debug_port != debug_port)) {
-		if (--playtimes) {
-			set_debug_port(new_debug_port);
-			goto try_next_time;
-		}
-		return -1;
-	}
-
-	loop = 10;
-	/* Reset the EHCI controller */
-	cmd = readl(&ehci_regs->command);
-	cmd |= CMD_RESET;
-	writel(cmd, &ehci_regs->command);
-	do {
-		cmd = readl(&ehci_regs->command);
-	} while ((cmd & CMD_RESET) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("can not reset ehci\n");
-		return -1;
-	}
-	dbgp_printk("ehci reset done\n");
-
-	/* Claim ownership, but do not enable yet */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_OWNER;
-	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
-	writel(ctrl, &ehci_debug->control);
-
-	/* Start the ehci running */
-	cmd = readl(&ehci_regs->command);
-	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
-	cmd |= CMD_RUN;
-	writel(cmd, &ehci_regs->command);
-
-	/* Ensure everything is routed to the EHCI */
-	writel(FLAG_CF, &ehci_regs->configured_flag);
-
-	/* Wait until the controller is no longer halted */
-	loop = 10;
-	do {
-		status = readl(&ehci_regs->status);
-	} while ((status & STS_HALT) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("ehci can be started\n");
-		return -1;
-	}
-	dbgp_printk("ehci started\n");
-
-	/* Wait for a device to show up in the debug port */
-	ret = ehci_wait_for_port(debug_port);
-	if (ret < 0) {
-		dbgp_printk("No device found in debug port\n");
-		goto next_debug_port;
-	}
-	dbgp_printk("ehci wait for port done\n");
-
-	/* Enable the debug port */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_CLAIM;
-	writel(ctrl, &ehci_debug->control);
-	ctrl = readl(&ehci_debug->control);
-	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
-		dbgp_printk("No device in debug port\n");
-		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
-		goto err;
-	}
-	dbgp_printk("debug ported enabled\n");
-
-	/* Completely transfer the debug device to the debug controller */
-	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
-	portsc &= ~PORT_PE;
-	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
-
-	dbgp_mdelay(100);
-
-	/* Find the debug device and make it device number 127 */
-	for (devnum = 0; devnum <= 127; devnum++) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
-			&dbgp_desc, sizeof(dbgp_desc));
-		if (ret > 0)
-			break;
-	}
-	if (devnum > 127) {
-		dbgp_printk("Could not find attached debug device\n");
-		goto err;
-	}
-	if (ret < 0) {
-		dbgp_printk("Attached device is not a debug device\n");
-		goto err;
-	}
-	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
-
-	/* Move the device to 127 if it isn't already there */
-	if (devnum != USB_DEBUG_DEVNUM) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
-		if (ret < 0) {
-			dbgp_printk("Could not move attached device to %d\n",
-				USB_DEBUG_DEVNUM);
-			goto err;
-		}
-		devnum = USB_DEBUG_DEVNUM;
-		dbgp_printk("debug device renamed to 127\n");
-	}
-
-	/* Enable the debug interface */
-	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
-		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
-	if (ret < 0) {
-		dbgp_printk(" Could not enable the debug device\n");
-		goto err;
-	}
-	dbgp_printk("debug interface enabled\n");
-
-	/* Perform a small write to get the even/odd data state in sync
-	 */
-	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
-	if (ret < 0) {
-		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
-		goto err;
-	}
-	dbgp_printk("small write doned\n");
-
-	return 0;
-err:
-	/* Things didn't work so remove my claim */
-	ctrl = readl(&ehci_debug->control);
-	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
-	writel(ctrl, &ehci_debug->control);
-	return -1;
-
-next_debug_port:
-	port_map_tried |= (1<<(debug_port - 1));
-	new_debug_port = ((debug_port-1+1)%n_ports) + 1;
-	if (port_map_tried != ((1<<n_ports) - 1)) {
-		set_debug_port(new_debug_port);
-		goto try_next_port;
-	}
-	if (--playtimes) {
-		set_debug_port(new_debug_port);
-		goto try_next_time;
-	}
-
-	return -1;
-}
-
-static int __init early_dbgp_init(char *s)
-{
-	u32 debug_port, bar, offset;
-	u32 bus, slot, func, cap;
-	void __iomem *ehci_bar;
-	u32 dbgp_num;
-	u32 bar_val;
-	char *e;
-	int ret;
-	u8 byte;
-
-	if (!early_pci_allowed())
-		return -1;
-
-	dbgp_num = 0;
-	if (*s)
-		dbgp_num = simple_strtoul(s, &e, 10);
-	dbgp_printk("dbgp_num: %d\n", dbgp_num);
-
-	cap = find_dbgp(dbgp_num, &bus, &slot, &func);
-	if (!cap)
-		return -1;
-
-	dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot,
-			 func);
-
-	debug_port = read_pci_config(bus, slot, func, cap);
-	bar = (debug_port >> 29) & 0x7;
-	bar = (bar * 4) + 0xc;
-	offset = (debug_port >> 16) & 0xfff;
-	dbgp_printk("bar: %02x offset: %03x\n", bar, offset);
-	if (bar != PCI_BASE_ADDRESS_0) {
-		dbgp_printk("only debug ports on bar 1 handled.\n");
-
-		return -1;
-	}
-
-	bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
-	dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset);
-	if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) {
-		dbgp_printk("only simple 32bit mmio bars supported\n");
-
-		return -1;
-	}
-
-	/* double check if the mem space is enabled */
-	byte = read_pci_config_byte(bus, slot, func, 0x04);
-	if (!(byte & 0x2)) {
-		byte  |= 0x02;
-		write_pci_config_byte(bus, slot, func, 0x04, byte);
-		dbgp_printk("mmio for ehci enabled\n");
-	}
-
-	/*
-	 * FIXME I don't have the bar size so just guess PAGE_SIZE is more
-	 * than enough.  1K is the biggest I have seen.
-	 */
-	set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK);
-	ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE);
-	ehci_bar += bar_val & ~PAGE_MASK;
-	dbgp_printk("ehci_bar: %p\n", ehci_bar);
-
-	ehci_caps  = ehci_bar;
-	ehci_regs  = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase));
-	ehci_debug = ehci_bar + offset;
-	ehci_dev.bus = bus;
-	ehci_dev.slot = slot;
-	ehci_dev.func = func;
-
-	detect_set_debug_port();
-
-	ret = ehci_setup();
-	if (ret < 0) {
-		dbgp_printk("ehci_setup failed\n");
-		ehci_debug = NULL;
-
-		return -1;
-	}
-
-	return 0;
-}
-
-static void early_dbgp_write(struct console *con, const char *str, u32 n)
-{
-	int chunk, ret;
-
-	if (!ehci_debug)
-		return;
-	while (n > 0) {
-		chunk = n;
-		if (chunk > DBGP_MAX_PACKET)
-			chunk = DBGP_MAX_PACKET;
-		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, str, chunk);
-		str += chunk;
-		n -= chunk;
-	}
-}
-
-static struct console early_dbgp_console = {
-	.name =		"earlydbg",
-	.write =	early_dbgp_write,
-	.flags =	CON_PRINTBUFFER,
-	.index =	-1,
-};
-#endif
-
 /* Direct interface for emergencies */
 static struct console *early_console = &early_vga_console;
 static int __initdata early_console_initialized;
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 19cb7d5..4e215ae 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_USB_MICROTEK)	+= image/
 obj-$(CONFIG_USB_SERIAL)	+= serial/
 
 obj-$(CONFIG_USB)		+= misc/
+obj-$(CONFIG_USB)		+= early/
 
 obj-$(CONFIG_USB_ATM)		+= atm/
 obj-$(CONFIG_USB_SPEEDTOUCH)	+= atm/
diff --git a/drivers/usb/early/Makefile b/drivers/usb/early/Makefile
new file mode 100644
index 0000000..dfedee8
--- /dev/null
+++ b/drivers/usb/early/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for early USB devices
+#
+
+obj-$(CONFIG_EARLY_PRINTK_DBGP)        += ehci-dbgp.o
diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
new file mode 100644
index 0000000..c7aa0aa
--- /dev/null
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -0,0 +1,723 @@
+#include <linux/console.h>
+#include <linux/errno.h>
+#include <linux/pci_regs.h>
+#include <linux/pci_ids.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/ehci_def.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+#include <asm/pci-direct.h>
+#include <asm/fixmap.h>
+
+static struct ehci_caps __iomem *ehci_caps;
+static struct ehci_regs __iomem *ehci_regs;
+static struct ehci_dbg_port __iomem *ehci_debug;
+static unsigned int dbgp_endpoint_out;
+
+struct ehci_dev {
+	u32 bus;
+	u32 slot;
+	u32 func;
+};
+
+static struct ehci_dev ehci_dev;
+
+#define USB_DEBUG_DEVNUM 127
+
+#define DBGP_DATA_TOGGLE	0x8800
+
+static inline u32 dbgp_pid_update(u32 x, u32 tok)
+{
+	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
+}
+
+static inline u32 dbgp_len_update(u32 x, u32 len)
+{
+	return (x & ~0x0f) | (len & 0x0f);
+}
+
+/*
+ * USB Packet IDs (PIDs)
+ */
+
+/* token */
+#define USB_PID_OUT		0xe1
+#define USB_PID_IN		0x69
+#define USB_PID_SOF		0xa5
+#define USB_PID_SETUP		0x2d
+/* handshake */
+#define USB_PID_ACK		0xd2
+#define USB_PID_NAK		0x5a
+#define USB_PID_STALL		0x1e
+#define USB_PID_NYET		0x96
+/* data */
+#define USB_PID_DATA0		0xc3
+#define USB_PID_DATA1		0x4b
+#define USB_PID_DATA2		0x87
+#define USB_PID_MDATA		0x0f
+/* Special */
+#define USB_PID_PREAMBLE	0x3c
+#define USB_PID_ERR		0x3c
+#define USB_PID_SPLIT		0x78
+#define USB_PID_PING		0xb4
+#define USB_PID_UNDEF_0		0xf0
+
+#define USB_PID_DATA_TOGGLE	0x88
+#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
+
+#define PCI_CAP_ID_EHCI_DEBUG	0xa
+
+#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
+#define HUB_SHORT_RESET_TIME	10
+#define HUB_LONG_RESET_TIME	200
+#define HUB_RESET_TIMEOUT	500
+
+#define DBGP_MAX_PACKET		8
+
+static int dbgp_wait_until_complete(void)
+{
+	u32 ctrl;
+	int loop = 0x100000;
+
+	do {
+		ctrl = readl(&ehci_debug->control);
+		/* Stop when the transaction is finished */
+		if (ctrl & DBGP_DONE)
+			break;
+	} while (--loop > 0);
+
+	if (!loop)
+		return -1;
+
+	/*
+	 * Now that we have observed the completed transaction,
+	 * clear the done bit.
+	 */
+	writel(ctrl | DBGP_DONE, &ehci_debug->control);
+	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
+}
+
+static void __init dbgp_mdelay(int ms)
+{
+	int i;
+
+	while (ms--) {
+		for (i = 0; i < 1000; i++)
+			outb(0x1, 0x80);
+	}
+}
+
+static void dbgp_breath(void)
+{
+	/* Sleep to give the debug port a chance to breathe */
+}
+
+static int dbgp_wait_until_done(unsigned ctrl)
+{
+	u32 pids, lpid;
+	int ret;
+	int loop = 3;
+
+retry:
+	writel(ctrl | DBGP_GO, &ehci_debug->control);
+	ret = dbgp_wait_until_complete();
+	pids = readl(&ehci_debug->pids);
+	lpid = DBGP_PID_GET(pids);
+
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * If the port is getting full or it has dropped data
+	 * start pacing ourselves, not necessary but it's friendly.
+	 */
+	if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET))
+		dbgp_breath();
+
+	/* If I get a NACK reissue the transmission */
+	if (lpid == USB_PID_NAK) {
+		if (--loop > 0)
+			goto retry;
+	}
+
+	return ret;
+}
+
+static void dbgp_set_data(const void *buf, int size)
+{
+	const unsigned char *bytes = buf;
+	u32 lo, hi;
+	int i;
+
+	lo = hi = 0;
+	for (i = 0; i < 4 && i < size; i++)
+		lo |= bytes[i] << (8*i);
+	for (; i < 8 && i < size; i++)
+		hi |= bytes[i] << (8*(i - 4));
+	writel(lo, &ehci_debug->data03);
+	writel(hi, &ehci_debug->data47);
+}
+
+static void __init dbgp_get_data(void *buf, int size)
+{
+	unsigned char *bytes = buf;
+	u32 lo, hi;
+	int i;
+
+	lo = readl(&ehci_debug->data03);
+	hi = readl(&ehci_debug->data47);
+	for (i = 0; i < 4 && i < size; i++)
+		bytes[i] = (lo >> (8*i)) & 0xff;
+	for (; i < 8 && i < size; i++)
+		bytes[i] = (hi >> (8*(i - 4))) & 0xff;
+}
+
+static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
+			 const char *bytes, int size)
+{
+	u32 pids, addr, ctrl;
+	int ret;
+
+	if (size > DBGP_MAX_PACKET)
+		return -1;
+
+	addr = DBGP_EPADDR(devnum, endpoint);
+
+	pids = readl(&ehci_debug->pids);
+	pids = dbgp_pid_update(pids, USB_PID_OUT);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, size);
+	ctrl |= DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	dbgp_set_data(bytes, size);
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	return ret;
+}
+
+static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
+				 int size)
+{
+	u32 pids, addr, ctrl;
+	int ret;
+
+	if (size > DBGP_MAX_PACKET)
+		return -1;
+
+	addr = DBGP_EPADDR(devnum, endpoint);
+
+	pids = readl(&ehci_debug->pids);
+	pids = dbgp_pid_update(pids, USB_PID_IN);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, size);
+	ctrl &= ~DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	if (size > ret)
+		size = ret;
+	dbgp_get_data(data, size);
+	return ret;
+}
+
+static int __init dbgp_control_msg(unsigned devnum, int requesttype,
+	int request, int value, int index, void *data, int size)
+{
+	u32 pids, addr, ctrl;
+	struct usb_ctrlrequest req;
+	int read;
+	int ret;
+
+	read = (requesttype & USB_DIR_IN) != 0;
+	if (size > (read ? DBGP_MAX_PACKET:0))
+		return -1;
+
+	/* Compute the control message */
+	req.bRequestType = requesttype;
+	req.bRequest = request;
+	req.wValue = cpu_to_le16(value);
+	req.wIndex = cpu_to_le16(index);
+	req.wLength = cpu_to_le16(size);
+
+	pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
+	addr = DBGP_EPADDR(devnum, 0);
+
+	ctrl = readl(&ehci_debug->control);
+	ctrl = dbgp_len_update(ctrl, sizeof(req));
+	ctrl |= DBGP_OUT;
+	ctrl |= DBGP_GO;
+
+	/* Send the setup message */
+	dbgp_set_data(&req, sizeof(req));
+	writel(addr, &ehci_debug->address);
+	writel(pids, &ehci_debug->pids);
+	ret = dbgp_wait_until_done(ctrl);
+	if (ret < 0)
+		return ret;
+
+	/* Read the result */
+	return dbgp_bulk_read(devnum, 0, data, size);
+}
+
+
+/* Find a PCI capability */
+static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap)
+{
+	u8 pos;
+	int bytes;
+
+	if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
+		PCI_STATUS_CAP_LIST))
+		return 0;
+
+	pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
+	for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
+		u8 id;
+
+		pos &= ~3;
+		id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
+		if (id == 0xff)
+			break;
+		if (id == cap)
+			return pos;
+
+		pos = read_pci_config_byte(num, slot, func,
+						 pos+PCI_CAP_LIST_NEXT);
+	}
+	return 0;
+}
+
+static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func)
+{
+	u32 class;
+
+	class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
+	if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI)
+		return 0;
+
+	return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
+}
+
+static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
+{
+	u32 bus, slot, func;
+
+	for (bus = 0; bus < 256; bus++) {
+		for (slot = 0; slot < 32; slot++) {
+			for (func = 0; func < 8; func++) {
+				unsigned cap;
+
+				cap = __find_dbgp(bus, slot, func);
+
+				if (!cap)
+					continue;
+				if (ehci_num-- != 0)
+					continue;
+				*rbus = bus;
+				*rslot = slot;
+				*rfunc = func;
+				return cap;
+			}
+		}
+	}
+	return 0;
+}
+
+static int __init ehci_reset_port(int port)
+{
+	u32 portsc;
+	u32 delay_time, delay;
+	int loop;
+
+	/* Reset the usb debug port */
+	portsc = readl(&ehci_regs->port_status[port - 1]);
+	portsc &= ~PORT_PE;
+	portsc |= PORT_RESET;
+	writel(portsc, &ehci_regs->port_status[port - 1]);
+
+	delay = HUB_ROOT_RESET_TIME;
+	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
+	     delay_time += delay) {
+		dbgp_mdelay(delay);
+
+		portsc = readl(&ehci_regs->port_status[port - 1]);
+		if (portsc & PORT_RESET) {
+			/* force reset to complete */
+			loop = 2;
+			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
+				&ehci_regs->port_status[port - 1]);
+			do {
+				portsc = readl(&ehci_regs->port_status[port-1]);
+			} while ((portsc & PORT_RESET) && (--loop > 0));
+		}
+
+		/* Device went away? */
+		if (!(portsc & PORT_CONNECT))
+			return -ENOTCONN;
+
+		/* bomb out completely if something weird happend */
+		if ((portsc & PORT_CSC))
+			return -EINVAL;
+
+		/* If we've finished resetting, then break out of the loop */
+		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
+			return 0;
+	}
+	return -EBUSY;
+}
+
+static int __init ehci_wait_for_port(int port)
+{
+	u32 status;
+	int ret, reps;
+
+	for (reps = 0; reps < 3; reps++) {
+		dbgp_mdelay(100);
+		status = readl(&ehci_regs->status);
+		if (status & STS_PCD) {
+			ret = ehci_reset_port(port);
+			if (ret == 0)
+				return 0;
+		}
+	}
+	return -ENOTCONN;
+}
+
+#ifdef DBGP_DEBUG
+# define dbgp_printk early_printk
+#else
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
+typedef void (*set_debug_port_t)(int port);
+
+static void __init default_set_debug_port(int port)
+{
+}
+
+static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
+
+static void __init nvidia_set_debug_port(int port)
+{
+	u32 dword;
+	dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+				 0x74);
+	dword &= ~(0x0f<<12);
+	dword |= ((port & 0x0f)<<12);
+	write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74,
+				 dword);
+	dbgp_printk("set debug port to %d\n", port);
+}
+
+static void __init detect_set_debug_port(void)
+{
+	u32 vendorid;
+
+	vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+		 0x00);
+
+	if ((vendorid & 0xffff) == 0x10de) {
+		dbgp_printk("using nvidia set_debug_port\n");
+		set_debug_port = nvidia_set_debug_port;
+	}
+}
+
+static int __init ehci_setup(void)
+{
+	struct usb_debug_descriptor dbgp_desc;
+	u32 cmd, ctrl, status, portsc, hcs_params;
+	u32 debug_port, new_debug_port = 0, n_ports;
+	u32  devnum;
+	int ret, i;
+	int loop;
+	int port_map_tried;
+	int playtimes = 3;
+
+try_next_time:
+	port_map_tried = 0;
+
+try_next_port:
+
+	hcs_params = readl(&ehci_caps->hcs_params);
+	debug_port = HCS_DEBUG_PORT(hcs_params);
+	n_ports    = HCS_N_PORTS(hcs_params);
+
+	dbgp_printk("debug_port: %d\n", debug_port);
+	dbgp_printk("n_ports:    %d\n", n_ports);
+
+	for (i = 1; i <= n_ports; i++) {
+		portsc = readl(&ehci_regs->port_status[i-1]);
+		dbgp_printk("portstatus%d: %08x\n", i, portsc);
+	}
+
+	if (port_map_tried && (new_debug_port != debug_port)) {
+		if (--playtimes) {
+			set_debug_port(new_debug_port);
+			goto try_next_time;
+		}
+		return -1;
+	}
+
+	loop = 10;
+	/* Reset the EHCI controller */
+	cmd = readl(&ehci_regs->command);
+	cmd |= CMD_RESET;
+	writel(cmd, &ehci_regs->command);
+	do {
+		cmd = readl(&ehci_regs->command);
+	} while ((cmd & CMD_RESET) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("can not reset ehci\n");
+		return -1;
+	}
+	dbgp_printk("ehci reset done\n");
+
+	/* Claim ownership, but do not enable yet */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_OWNER;
+	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
+	writel(ctrl, &ehci_debug->control);
+
+	/* Start the ehci running */
+	cmd = readl(&ehci_regs->command);
+	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
+	cmd |= CMD_RUN;
+	writel(cmd, &ehci_regs->command);
+
+	/* Ensure everything is routed to the EHCI */
+	writel(FLAG_CF, &ehci_regs->configured_flag);
+
+	/* Wait until the controller is no longer halted */
+	loop = 10;
+	do {
+		status = readl(&ehci_regs->status);
+	} while ((status & STS_HALT) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("ehci can be started\n");
+		return -1;
+	}
+	dbgp_printk("ehci started\n");
+
+	/* Wait for a device to show up in the debug port */
+	ret = ehci_wait_for_port(debug_port);
+	if (ret < 0) {
+		dbgp_printk("No device found in debug port\n");
+		goto next_debug_port;
+	}
+	dbgp_printk("ehci wait for port done\n");
+
+	/* Enable the debug port */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_CLAIM;
+	writel(ctrl, &ehci_debug->control);
+	ctrl = readl(&ehci_debug->control);
+	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
+		dbgp_printk("No device in debug port\n");
+		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
+		goto err;
+	}
+	dbgp_printk("debug ported enabled\n");
+
+	/* Completely transfer the debug device to the debug controller */
+	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
+	portsc &= ~PORT_PE;
+	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
+
+	dbgp_mdelay(100);
+
+	/* Find the debug device and make it device number 127 */
+	for (devnum = 0; devnum <= 127; devnum++) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
+			&dbgp_desc, sizeof(dbgp_desc));
+		if (ret > 0)
+			break;
+	}
+	if (devnum > 127) {
+		dbgp_printk("Could not find attached debug device\n");
+		goto err;
+	}
+	if (ret < 0) {
+		dbgp_printk("Attached device is not a debug device\n");
+		goto err;
+	}
+	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
+
+	/* Move the device to 127 if it isn't already there */
+	if (devnum != USB_DEBUG_DEVNUM) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
+		if (ret < 0) {
+			dbgp_printk("Could not move attached device to %d\n",
+				USB_DEBUG_DEVNUM);
+			goto err;
+		}
+		devnum = USB_DEBUG_DEVNUM;
+		dbgp_printk("debug device renamed to 127\n");
+	}
+
+	/* Enable the debug interface */
+	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
+		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
+	if (ret < 0) {
+		dbgp_printk(" Could not enable the debug device\n");
+		goto err;
+	}
+	dbgp_printk("debug interface enabled\n");
+
+	/* Perform a small write to get the even/odd data state in sync
+	 */
+	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
+	if (ret < 0) {
+		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
+		goto err;
+	}
+	dbgp_printk("small write doned\n");
+
+	return 0;
+err:
+	/* Things didn't work so remove my claim */
+	ctrl = readl(&ehci_debug->control);
+	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
+	writel(ctrl, &ehci_debug->control);
+	return -1;
+
+next_debug_port:
+	port_map_tried |= (1<<(debug_port - 1));
+	new_debug_port = ((debug_port-1+1)%n_ports) + 1;
+	if (port_map_tried != ((1<<n_ports) - 1)) {
+		set_debug_port(new_debug_port);
+		goto try_next_port;
+	}
+	if (--playtimes) {
+		set_debug_port(new_debug_port);
+		goto try_next_time;
+	}
+
+	return -1;
+}
+
+int __init early_dbgp_init(char *s)
+{
+	u32 debug_port, bar, offset;
+	u32 bus, slot, func, cap;
+	void __iomem *ehci_bar;
+	u32 dbgp_num;
+	u32 bar_val;
+	char *e;
+	int ret;
+	u8 byte;
+
+	if (!early_pci_allowed())
+		return -1;
+
+	dbgp_num = 0;
+	if (*s)
+		dbgp_num = simple_strtoul(s, &e, 10);
+	dbgp_printk("dbgp_num: %d\n", dbgp_num);
+
+	cap = find_dbgp(dbgp_num, &bus, &slot, &func);
+	if (!cap)
+		return -1;
+
+	dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot,
+			 func);
+
+	debug_port = read_pci_config(bus, slot, func, cap);
+	bar = (debug_port >> 29) & 0x7;
+	bar = (bar * 4) + 0xc;
+	offset = (debug_port >> 16) & 0xfff;
+	dbgp_printk("bar: %02x offset: %03x\n", bar, offset);
+	if (bar != PCI_BASE_ADDRESS_0) {
+		dbgp_printk("only debug ports on bar 1 handled.\n");
+
+		return -1;
+	}
+
+	bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
+	dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset);
+	if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) {
+		dbgp_printk("only simple 32bit mmio bars supported\n");
+
+		return -1;
+	}
+
+	/* double check if the mem space is enabled */
+	byte = read_pci_config_byte(bus, slot, func, 0x04);
+	if (!(byte & 0x2)) {
+		byte  |= 0x02;
+		write_pci_config_byte(bus, slot, func, 0x04, byte);
+		dbgp_printk("mmio for ehci enabled\n");
+	}
+
+	/*
+	 * FIXME I don't have the bar size so just guess PAGE_SIZE is more
+	 * than enough.  1K is the biggest I have seen.
+	 */
+	set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK);
+	ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE);
+	ehci_bar += bar_val & ~PAGE_MASK;
+	dbgp_printk("ehci_bar: %p\n", ehci_bar);
+
+	ehci_caps  = ehci_bar;
+	ehci_regs  = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase));
+	ehci_debug = ehci_bar + offset;
+	ehci_dev.bus = bus;
+	ehci_dev.slot = slot;
+	ehci_dev.func = func;
+
+	detect_set_debug_port();
+
+	ret = ehci_setup();
+	if (ret < 0) {
+		dbgp_printk("ehci_setup failed\n");
+		ehci_debug = NULL;
+
+		return -1;
+	}
+
+	return 0;
+}
+
+static void early_dbgp_write(struct console *con, const char *str, u32 n)
+{
+	int chunk, ret;
+
+	if (!ehci_debug)
+		return;
+	while (n > 0) {
+		chunk = n;
+		if (chunk > DBGP_MAX_PACKET)
+			chunk = DBGP_MAX_PACKET;
+		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
+			dbgp_endpoint_out, str, chunk);
+		str += chunk;
+		n -= chunk;
+	}
+}
+
+struct console early_dbgp_console = {
+	.name =		"earlydbg",
+	.write =	early_dbgp_write,
+	.flags =	CON_PRINTBUFFER,
+	.index =	-1,
+};
+
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 5b88e36..0e22b5f 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -157,4 +157,10 @@ struct ehci_dbg_port {
 #define DBGP_EPADDR(dev, ep)	(((dev)<<8)|(ep))
 } __attribute__ ((packed));
 
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+#include <linux/init.h>
+extern int __init early_dbgp_init(char *s);
+extern struct console early_dbgp_console;
+#endif /* CONFIG_EARLY_PRINTK_DBGP */
+
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

[PATCH 02/10] usb,early_printk: insert cr prior to nl as needed

[Jason Wessel]

The rs232 drivers send a carriage return prior to a new line in the
early printk code.

The usb debug driver should do the same because you want to be able to
use the same terminal programs and tools for analysis of early printk
data.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   22 ++++++++++++++++------
 1 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index c7aa0aa..51ec414 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -700,17 +700,27 @@ int __init early_dbgp_init(char *s)
 static void early_dbgp_write(struct console *con, const char *str, u32 n)
 {
 	int chunk, ret;
+	char buf[DBGP_MAX_PACKET];
+	int use_cr = 0;
 
 	if (!ehci_debug)
 		return;
 	while (n > 0) {
-		chunk = n;
-		if (chunk > DBGP_MAX_PACKET)
-			chunk = DBGP_MAX_PACKET;
+		for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0;
+		     str++, chunk++, n--) {
+			if (!use_cr && *str == '\n') {
+				use_cr = 1;
+				buf[chunk] = '\r';
+				str--;
+				n++;
+				continue;
+			}
+			if (use_cr)
+				use_cr = 0;
+			buf[chunk] = *str;
+		}
 		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, str, chunk);
-		str += chunk;
-		n -= chunk;
+			dbgp_endpoint_out, buf, chunk);
 	}
 }
 
-- 
1.6.0.3.523.g304d0

[PATCH 03/10] ehci-dbgp: Execute early BIOS hand off

[Jason Wessel]

The PCI quirk code executes a BIOS hand off to obtain full control of
the EHCI host controller, the self contained ehci-dbgp driver must do
the same thing using the early PCI API, else the BIOS can cause a
fatal fault.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   49 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 49 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 51ec414..f4bfe31 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -435,6 +435,53 @@ static void __init detect_set_debug_port(void)
 	}
 }
 
+/* The code in early_ehci_bios_handoff() is derived from the usb pci
+ * quirk initialization, but altered so as to use the early PCI
+ * routines. */
+#define EHCI_USBLEGSUP_BIOS	(1 << 16)	/* BIOS semaphore */
+#define EHCI_USBLEGCTLSTS	4		/* legacy control/status */
+static void __init early_ehci_bios_handoff(void)
+{
+	u32 hcc_params = readl(&ehci_caps->hcc_params);
+	int offset = (hcc_params >> 8) & 0xff;
+	u32 cap;
+	int msec;
+
+	if (!offset)
+		return;
+
+	cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+			      ehci_dev.func, offset);
+	dbgp_printk("dbgp: ehci BIOS state %08x\n", cap);
+
+	if ((cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS)) {
+		dbgp_printk("dbgp: BIOS handoff\n");
+		write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset + 3, 1);
+	}
+
+	/* if boot firmware now owns EHCI, spin till it hands it over. */
+	msec = 1000;
+	while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
+		mdelay(10);
+		msec -= 10;
+		cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset);
+	}
+
+	if (cap & EHCI_USBLEGSUP_BIOS) {
+		/* well, possibly buggy BIOS... try to shut it down,
+		 * and hope nothing goes too wrong */
+		dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap);
+		write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+				      ehci_dev.func, offset + 2, 0);
+	}
+
+	/* just in case, always disable EHCI SMIs */
+	write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+			      offset + EHCI_USBLEGCTLSTS, 0);
+}
+
 static int __init ehci_setup(void)
 {
 	struct usb_debug_descriptor dbgp_desc;
@@ -446,6 +493,8 @@ static int __init ehci_setup(void)
 	int port_map_tried;
 	int playtimes = 3;
 
+	early_ehci_bios_handoff();
+
 try_next_time:
 	port_map_tried = 0;
 
-- 
1.6.0.3.523.g304d0

[PATCH 04/10] usb,early_printk: EHCI debug controller initialization delays

[Jason Wessel]

When using the EHCI host controller as a polled device, a bit more
tolerance is required in terms of delays.  On some 3+ghz systems the
cpu loops were faster than the EHCI device mmio and resulted in the
controller failing to initialize.

On at least one first generation EHCI controller when it was not
operating in interrupt mode, it would fail to report a port change
status, but executing the port reset allowed the debug controller to
work correctly anyway.  This errata causes a one time 300ms delay in
the boot time, where as the typical delay is 1-5ms for an EHCI
controller that does not have this errata.

The debug printk's were fixed to have the correct state messages, and
there was a conversion from using early_printk to printk to avoid
calling the dbgp driver while debugging the initialization.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   45 +++++++++++++++++++++++-----------------
 1 files changed, 26 insertions(+), 19 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index f4bfe31..6198ebd 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -9,6 +9,12 @@
 #include <asm/pci-direct.h>
 #include <asm/fixmap.h>
 
+#ifdef DBGP_DEBUG
+# define dbgp_printk printk
+#else
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
 static struct ehci_caps __iomem *ehci_caps;
 static struct ehci_regs __iomem *ehci_regs;
 static struct ehci_dbg_port __iomem *ehci_debug;
@@ -342,6 +348,7 @@ static int __init ehci_reset_port(int port)
 	u32 delay_time, delay;
 	int loop;
 
+	dbgp_printk("ehci_reset_port %i\n", port);
 	/* Reset the usb debug port */
 	portsc = readl(&ehci_regs->port_status[port - 1]);
 	portsc &= ~PORT_PE;
@@ -352,14 +359,17 @@ static int __init ehci_reset_port(int port)
 	for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
 	     delay_time += delay) {
 		dbgp_mdelay(delay);
-
 		portsc = readl(&ehci_regs->port_status[port - 1]);
+		if (!(portsc & PORT_RESET))
+			break;
+	}
 		if (portsc & PORT_RESET) {
 			/* force reset to complete */
-			loop = 2;
+			loop = 100 * 1000;
 			writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
 				&ehci_regs->port_status[port - 1]);
 			do {
+				udelay(1);
 				portsc = readl(&ehci_regs->port_status[port-1]);
 			} while ((portsc & PORT_RESET) && (--loop > 0));
 		}
@@ -375,7 +385,6 @@ static int __init ehci_reset_port(int port)
 		/* If we've finished resetting, then break out of the loop */
 		if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
 			return 0;
-	}
 	return -EBUSY;
 }
 
@@ -384,24 +393,18 @@ static int __init ehci_wait_for_port(int port)
 	u32 status;
 	int ret, reps;
 
-	for (reps = 0; reps < 3; reps++) {
-		dbgp_mdelay(100);
+	for (reps = 0; reps < 300; reps++) {
 		status = readl(&ehci_regs->status);
-		if (status & STS_PCD) {
-			ret = ehci_reset_port(port);
-			if (ret == 0)
-				return 0;
-		}
+		if (status & STS_PCD)
+			break;
+		dbgp_mdelay(1);
 	}
+	ret = ehci_reset_port(port);
+	if (ret == 0)
+		return 0;
 	return -ENOTCONN;
 }
 
-#ifdef DBGP_DEBUG
-# define dbgp_printk early_printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
-
 typedef void (*set_debug_port_t)(int port);
 
 static void __init default_set_debug_port(int port)
@@ -520,7 +523,7 @@ try_next_port:
 		return -1;
 	}
 
-	loop = 10;
+	loop = 250 * 1000;
 	/* Reset the EHCI controller */
 	cmd = readl(&ehci_regs->command);
 	cmd |= CMD_RESET;
@@ -540,6 +543,7 @@ try_next_port:
 	ctrl |= DBGP_OWNER;
 	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
 	writel(ctrl, &ehci_debug->control);
+	udelay(1);
 
 	/* Start the ehci running */
 	cmd = readl(&ehci_regs->command);
@@ -554,10 +558,13 @@ try_next_port:
 	loop = 10;
 	do {
 		status = readl(&ehci_regs->status);
-	} while ((status & STS_HALT) && (--loop > 0));
+		if (!(status & STS_HALT))
+			break;
+		udelay(1);
+	} while (--loop > 0);
 
 	if (!loop) {
-		dbgp_printk("ehci can be started\n");
+		dbgp_printk("ehci can not be started\n");
 		return -1;
 	}
 	dbgp_printk("ehci started\n");
-- 
1.6.0.3.523.g304d0

[PATCH 05/10] printk,early_printk,console: Allow more than one early console

[Jason Wessel]

It is very nice to be able to use one early boot device to debug
another or to have multiple places you can see the early boot
diagnostics, such as the vga screen or serial device.

This patch changes the early_printk console device registration to
allow more than one early printk device to get registered via
register_console().

A corresponding change is required to the console registration code
such that it will properly unregister any console marked with the
CON_BOOT flag via a simple loop during a console handover or at late
init time.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
---
 arch/x86/kernel/early_printk.c |   65 ++++++++++++++++++++-------------------
 kernel/printk.c                |   41 ++++++++++++++++---------
 2 files changed, 59 insertions(+), 47 deletions(-)

diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index 519a5e1..2acfd3f 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -176,10 +176,19 @@ asmlinkage void early_printk(const char *fmt, ...)
 	va_end(ap);
 }
 
+static inline void early_console_register(struct console *con, int keep_early)
+{
+	early_console = con;
+	if (keep_early)
+		early_console->flags &= ~CON_BOOT;
+	else
+		early_console->flags |= CON_BOOT;
+	register_console(early_console);
+}
 
 static int __init setup_early_printk(char *buf)
 {
-	int keep_early;
+	int keep;
 
 	if (!buf)
 		return 0;
@@ -188,42 +197,34 @@ static int __init setup_early_printk(char *buf)
 		return 0;
 	early_console_initialized = 1;
 
-	keep_early = (strstr(buf, "keep") != NULL);
-
-	if (!strncmp(buf, "serial", 6)) {
-		early_serial_init(buf + 6);
-		early_console = &early_serial_console;
-	} else if (!strncmp(buf, "ttyS", 4)) {
-		early_serial_init(buf);
-		early_console = &early_serial_console;
-	} else if (!strncmp(buf, "vga", 3)
-		&& boot_params.screen_info.orig_video_isVGA == 1) {
-		max_xpos = boot_params.screen_info.orig_video_cols;
-		max_ypos = boot_params.screen_info.orig_video_lines;
-		current_ypos = boot_params.screen_info.orig_y;
-		early_console = &early_vga_console;
+	keep = (strstr(buf, "keep") != NULL);
+
+	while (*buf != '\0') {
+		if (!strncmp(buf, "serial", 6)) {
+			early_serial_init(buf + 6);
+			early_console_register(&early_serial_console, keep);
+		}
+		if (!strncmp(buf, "ttyS", 4)) {
+			early_serial_init(buf + 4);
+			early_console_register(&early_serial_console, keep);
+		}
+		if (!strncmp(buf, "vga", 3) &&
+		    boot_params.screen_info.orig_video_isVGA == 1) {
+			max_xpos = boot_params.screen_info.orig_video_cols;
+			max_ypos = boot_params.screen_info.orig_video_lines;
+			current_ypos = boot_params.screen_info.orig_y;
+			early_console_register(&early_vga_console, keep);
+		}
 #ifdef CONFIG_EARLY_PRINTK_DBGP
-	} else if (!strncmp(buf, "dbgp", 4)) {
-		if (early_dbgp_init(buf+4) < 0)
-			return 0;
-		early_console = &early_dbgp_console;
-		/*
-		 * usb subsys will reset ehci controller, so don't keep
-		 * that early console
-		 */
-		keep_early = 0;
+		if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
+			early_console_register(&early_dbgp_console, keep);
 #endif
 #ifdef CONFIG_HVC_XEN
-	} else if (!strncmp(buf, "xen", 3)) {
-		early_console = &xenboot_console;
+		if (!strncmp(buf, "xen", 3))
+			early_console_register(&xenboot_console, keep);
 #endif
+		buf++;
 	}
-
-	if (keep_early)
-		early_console->flags &= ~CON_BOOT;
-	else
-		early_console->flags |= CON_BOOT;
-	register_console(early_console);
 	return 0;
 }
 
diff --git a/kernel/printk.c b/kernel/printk.c
index b4d97b5..45e0cec 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1129,6 +1129,28 @@ void console_start(struct console *console)
 }
 EXPORT_SYMBOL(console_start);
 
+static int disable_boot_consoles(void)
+{
+	struct console *bootconsole = console_drivers;
+	struct console *nextcon;
+	if (!bootconsole)
+		return 0;
+	while (bootconsole) {
+		nextcon = bootconsole->next;
+		if (bootconsole->flags & CON_BOOT) {
+			printk(KERN_INFO "turn off boot console %s%d\n",
+			       console_drivers->name, console_drivers->index);
+			if (unregister_console(bootconsole) != 0)
+				printk(KERN_ERR "ERROR unregistering %s%d\n",
+				       console_drivers->name,
+				       console_drivers->index);
+		}
+		bootconsole = nextcon;
+	}
+	return 0;
+}
+late_initcall(disable_boot_consoles);
+
 /*
  * The console driver calls this routine during kernel initialization
  * to register the console printing procedure with printk() and to
@@ -1142,8 +1164,7 @@ void register_console(struct console *console)
 	struct console *bootconsole = NULL;
 
 	if (console_drivers) {
-		if (console->flags & CON_BOOT)
-			return;
+
 		if (console_drivers->flags & CON_BOOT)
 			bootconsole = console_drivers;
 	}
@@ -1216,6 +1237,7 @@ void register_console(struct console *console)
 		       console->name, console->index);
 		unregister_console(bootconsole);
 		console->flags &= ~CON_PRINTBUFFER;
+		disable_boot_consoles();
 	} else {
 		printk(KERN_INFO "console [%s%d] enabled\n",
 		       console->name, console->index);
@@ -1280,24 +1302,13 @@ int unregister_console(struct console *console)
 	if (console_drivers != NULL && console->flags & CON_CONSDEV)
 		console_drivers->flags |= CON_CONSDEV;
 
+	if (!res)
+		console->index = -1;
 	release_console_sem();
 	return res;
 }
 EXPORT_SYMBOL(unregister_console);
 
-static int __init disable_boot_consoles(void)
-{
-	if (console_drivers != NULL) {
-		if (console_drivers->flags & CON_BOOT) {
-			printk(KERN_INFO "turn off boot console %s%d\n",
-				console_drivers->name, console_drivers->index);
-			return unregister_console(console_drivers);
-		}
-	}
-	return 0;
-}
-late_initcall(disable_boot_consoles);
-
 #if defined CONFIG_PRINTK
 
 /*
-- 
1.6.0.3.523.g304d0

[PATCH 06/10] ehci-dbgp: stability improvements and external re-init

[Jason Wessel]

This patch implements several changes:

1) Improve the capability to debug the dbgp driver

   The dbgp_ehci_status() was added in a number of places to report
   the critical ehci registers to diagnose the cause of a failure of
   the ehci-dbgp driver.

2) Capability to survive the host controller initialization

   The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were
   added so as to allow the ehci-dbgp to re-initialize after the ehci
   host controller is reset by the standard host controller driver.
   This same routine is common for the early startup or
   re-initialization.

   This resulted in the need to move some of the initialization code
   out of the __init section because the ehci driver has the
   possibility to be loaded later on as a kernel module.

3) Stability improvements for device initialization

   The device enumeration from 0 to 127 has the possibility to fail
   the first time after a warm reset on some older EHCI debug
   controllers.  The enumeration will be tried up to 3 times to
   account for this failure case.

   The dbg_wait_until_complete() was changed to wait up to 250 ms
   before failing which only comes into play during device
   initialization. The maximum delay will never get hit during the
   course of normal operation of the driver, unless the device got
   unplugged or there was a ehci controller failure, in which case the
   dbgp device driver will shut itself down.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |  442 +++++++++++++++++++++++++++--------------
 include/linux/usb/ehci_def.h  |    5 +
 2 files changed, 299 insertions(+), 148 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 6198ebd..06e05ea 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -1,5 +1,19 @@
+/*
+ * Standalone EHCI usb debug driver
+ *
+ * Originally written by:
+ *  Eric W. Biederman" <ebiederm@xmission.com> and
+ *  Yinghai Lu <yhlu.kernel@gmail.com>
+ *
+ * Changes for early/late printk and HW errata:
+ *  Jason Wessel <jason.wessel@windriver.com>
+ *  Copyright (C) 2009 Wind River Systems, Inc.
+ *
+ */
+
 #include <linux/console.h>
 #include <linux/errno.h>
+#include <linux/module.h>
 #include <linux/pci_regs.h>
 #include <linux/pci_ids.h>
 #include <linux/usb/ch9.h>
@@ -9,15 +23,37 @@
 #include <asm/pci-direct.h>
 #include <asm/fixmap.h>
 
-#ifdef DBGP_DEBUG
-# define dbgp_printk printk
-#else
-static inline void dbgp_printk(const char *fmt, ...) { }
-#endif
+/* The code here is intended to talk directly to the EHCI debug port
+ * and does not require that you have any kind of USB host controller
+ * drivers or USB device drivers compiled into the kernel.
+ *
+ * If you make a change to anything in here, the following test cases
+ * need to pass where a USB debug device works in the following
+ * configurations.
+ *
+ * 1. boot args:  earlyprintk=dbgp
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ * 2. boot args: earlyprintk=dbgp,keep
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ * 3. boot args: earlyprintk=dbgp console=ttyUSB0
+ *     o kernel has CONFIG_USB_EHCI_HCD=y and
+ *       CONFIG_USB_SERIAL_DEBUG=y
+ * 4. boot args: earlyprintk=vga,dbgp
+ *     o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
+ *     o kernel compiled with CONFIG_USB_EHCI_HCD=y
+ *
+ * For the 4th configuration you can turn on or off the DBGP_DEBUG
+ * such that you can debug the dbgp device's driver code.
+ */
+
+static int dbgp_phys_port = 1;
 
 static struct ehci_caps __iomem *ehci_caps;
 static struct ehci_regs __iomem *ehci_regs;
 static struct ehci_dbg_port __iomem *ehci_debug;
+static int dbgp_not_safe; /* Cannot use debug device during ehci reset */
 static unsigned int dbgp_endpoint_out;
 
 struct ehci_dev {
@@ -32,6 +68,26 @@ static struct ehci_dev ehci_dev;
 
 #define DBGP_DATA_TOGGLE	0x8800
 
+#ifdef DBGP_DEBUG
+#define dbgp_printk printk
+static void dbgp_ehci_status(char *str)
+{
+	if (!ehci_debug)
+		return;
+	dbgp_printk("dbgp: %s\n", str);
+	dbgp_printk("  Debug control: %08x", readl(&ehci_debug->control));
+	dbgp_printk("  ehci cmd     : %08x", readl(&ehci_regs->command));
+	dbgp_printk("  ehci conf flg: %08x\n",
+		    readl(&ehci_regs->configured_flag));
+	dbgp_printk("  ehci status  : %08x", readl(&ehci_regs->status));
+	dbgp_printk("  ehci portsc  : %08x\n",
+		    readl(&ehci_regs->port_status[dbgp_phys_port - 1]));
+}
+#else
+static inline void dbgp_ehci_status(char *str) { }
+static inline void dbgp_printk(const char *fmt, ...) { }
+#endif
+
 static inline u32 dbgp_pid_update(u32 x, u32 tok)
 {
 	return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff);
@@ -79,21 +135,23 @@ static inline u32 dbgp_len_update(u32 x, u32 len)
 #define HUB_RESET_TIMEOUT	500
 
 #define DBGP_MAX_PACKET		8
+#define DBGP_TIMEOUT		(250 * 1000)
 
 static int dbgp_wait_until_complete(void)
 {
 	u32 ctrl;
-	int loop = 0x100000;
+	int loop = DBGP_TIMEOUT;
 
 	do {
 		ctrl = readl(&ehci_debug->control);
 		/* Stop when the transaction is finished */
 		if (ctrl & DBGP_DONE)
 			break;
+		udelay(1);
 	} while (--loop > 0);
 
 	if (!loop)
-		return -1;
+		return -DBGP_TIMEOUT;
 
 	/*
 	 * Now that we have observed the completed transaction,
@@ -103,7 +161,7 @@ static int dbgp_wait_until_complete(void)
 	return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
 }
 
-static void __init dbgp_mdelay(int ms)
+static inline void dbgp_mdelay(int ms)
 {
 	int i;
 
@@ -130,8 +188,17 @@ retry:
 	pids = readl(&ehci_debug->pids);
 	lpid = DBGP_PID_GET(pids);
 
-	if (ret < 0)
+	if (ret < 0) {
+		/* A -DBGP_TIMEOUT failure here means the device has
+		 * failed, perhaps because it was unplugged, in which
+		 * case we do not want to hang the system so the dbgp
+		 * will be marked as unsafe to use.  EHCI reset is the
+		 * only way to recover if you unplug the dbgp device.
+		 */
+		if (ret == -DBGP_TIMEOUT && !dbgp_not_safe)
+			dbgp_not_safe = 1;
 		return ret;
+	}
 
 	/*
 	 * If the port is getting full or it has dropped data
@@ -149,7 +216,7 @@ retry:
 	return ret;
 }
 
-static void dbgp_set_data(const void *buf, int size)
+static inline void dbgp_set_data(const void *buf, int size)
 {
 	const unsigned char *bytes = buf;
 	u32 lo, hi;
@@ -164,7 +231,7 @@ static void dbgp_set_data(const void *buf, int size)
 	writel(hi, &ehci_debug->data47);
 }
 
-static void __init dbgp_get_data(void *buf, int size)
+static inline void dbgp_get_data(void *buf, int size)
 {
 	unsigned char *bytes = buf;
 	u32 lo, hi;
@@ -208,7 +275,7 @@ static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
 	return ret;
 }
 
-static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
+static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
 				 int size)
 {
 	u32 pids, addr, ctrl;
@@ -239,7 +306,7 @@ static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
 	return ret;
 }
 
-static int __init dbgp_control_msg(unsigned devnum, int requesttype,
+static int dbgp_control_msg(unsigned devnum, int requesttype,
 	int request, int value, int index, void *data, int size)
 {
 	u32 pids, addr, ctrl;
@@ -342,13 +409,179 @@ static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
 	return 0;
 }
 
+static int dbgp_ehci_startup(void)
+{
+	u32 ctrl, cmd, status;
+	int loop;
+
+	/* Claim ownership, but do not enable yet */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_OWNER;
+	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
+	writel(ctrl, &ehci_debug->control);
+	udelay(1);
+
+	dbgp_ehci_status("EHCI startup");
+	/* Start the ehci running */
+	cmd = readl(&ehci_regs->command);
+	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
+	cmd |= CMD_RUN;
+	writel(cmd, &ehci_regs->command);
+
+	/* Ensure everything is routed to the EHCI */
+	writel(FLAG_CF, &ehci_regs->configured_flag);
+
+	/* Wait until the controller is no longer halted */
+	loop = 10;
+	do {
+		status = readl(&ehci_regs->status);
+		if (!(status & STS_HALT))
+			break;
+		udelay(1);
+	} while (--loop > 0);
+
+	if (!loop) {
+		dbgp_printk("ehci can not be started\n");
+		return -ENODEV;
+	}
+	dbgp_printk("ehci started\n");
+	return 0;
+}
+
+static int dbgp_ehci_controller_reset(void)
+{
+	int loop = 250 * 1000;
+	u32 cmd;
+
+	/* Reset the EHCI controller */
+	cmd = readl(&ehci_regs->command);
+	cmd |= CMD_RESET;
+	writel(cmd, &ehci_regs->command);
+	do {
+		cmd = readl(&ehci_regs->command);
+	} while ((cmd & CMD_RESET) && (--loop > 0));
+
+	if (!loop) {
+		dbgp_printk("can not reset ehci\n");
+		return -1;
+	}
+	dbgp_ehci_status("ehci reset done");
+	return 0;
+}
+static int ehci_wait_for_port(int port);
+/* Return 0 on success
+ * Return -ENODEV for any general failure
+ * Return -EIO if wait for port fails
+ */
+int dbgp_external_startup(void)
+{
+	int devnum;
+	struct usb_debug_descriptor dbgp_desc;
+	int ret;
+	u32 ctrl, portsc;
+	int dbg_port = dbgp_phys_port;
+	int tries = 3;
+
+	ret = dbgp_ehci_startup();
+	if (ret)
+		return ret;
+
+	/* Wait for a device to show up in the debug port */
+	ret = ehci_wait_for_port(dbg_port);
+	if (ret < 0) {
+		portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+		dbgp_printk("No device found in debug port\n");
+		return -EIO;
+	}
+	dbgp_ehci_status("wait for port done");
+
+	/* Enable the debug port */
+	ctrl = readl(&ehci_debug->control);
+	ctrl |= DBGP_CLAIM;
+	writel(ctrl, &ehci_debug->control);
+	ctrl = readl(&ehci_debug->control);
+	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
+		dbgp_printk("No device in debug port\n");
+		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
+		return -ENODEV;
+	}
+	dbgp_ehci_status("debug ported enabled");
+
+	/* Completely transfer the debug device to the debug controller */
+	portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+	portsc &= ~PORT_PE;
+	writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
+
+	dbgp_mdelay(100);
+
+try_again:
+	/* Find the debug device and make it device number 127 */
+	for (devnum = 0; devnum <= 127; devnum++) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
+			&dbgp_desc, sizeof(dbgp_desc));
+		if (ret > 0)
+			break;
+	}
+	if (devnum > 127) {
+		dbgp_printk("Could not find attached debug device\n");
+		goto err;
+	}
+	if (ret < 0) {
+		dbgp_printk("Attached device is not a debug device\n");
+		goto err;
+	}
+	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
+
+	/* Move the device to 127 if it isn't already there */
+	if (devnum != USB_DEBUG_DEVNUM) {
+		ret = dbgp_control_msg(devnum,
+			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
+		if (ret < 0) {
+			dbgp_printk("Could not move attached device to %d\n",
+				USB_DEBUG_DEVNUM);
+			goto err;
+		}
+		devnum = USB_DEBUG_DEVNUM;
+		dbgp_printk("debug device renamed to 127\n");
+	}
+
+	/* Enable the debug interface */
+	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
+		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
+		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
+	if (ret < 0) {
+		dbgp_printk(" Could not enable the debug device\n");
+		goto err;
+	}
+	dbgp_printk("debug interface enabled\n");
+	/* Perform a small write to get the even/odd data state in sync
+	 */
+	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
+	if (ret < 0) {
+		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
+		goto err;
+	}
+	dbgp_printk("small write doned\n");
+	dbgp_not_safe = 0;
+
+	return 0;
+err:
+	if (tries--)
+		goto try_again;
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(dbgp_external_startup);
+
 static int __init ehci_reset_port(int port)
 {
 	u32 portsc;
 	u32 delay_time, delay;
 	int loop;
 
-	dbgp_printk("ehci_reset_port %i\n", port);
+	dbgp_ehci_status("reset port");
 	/* Reset the usb debug port */
 	portsc = readl(&ehci_regs->port_status[port - 1]);
 	portsc &= ~PORT_PE;
@@ -388,7 +621,7 @@ static int __init ehci_reset_port(int port)
 	return -EBUSY;
 }
 
-static int __init ehci_wait_for_port(int port)
+static int ehci_wait_for_port(int port)
 {
 	u32 status;
 	int ret, reps;
@@ -487,12 +720,9 @@ static void __init early_ehci_bios_handoff(void)
 
 static int __init ehci_setup(void)
 {
-	struct usb_debug_descriptor dbgp_desc;
-	u32 cmd, ctrl, status, portsc, hcs_params;
+	u32 ctrl, portsc, hcs_params;
 	u32 debug_port, new_debug_port = 0, n_ports;
-	u32  devnum;
 	int ret, i;
-	int loop;
 	int port_map_tried;
 	int playtimes = 3;
 
@@ -505,10 +735,12 @@ try_next_port:
 
 	hcs_params = readl(&ehci_caps->hcs_params);
 	debug_port = HCS_DEBUG_PORT(hcs_params);
+	dbgp_phys_port = debug_port;
 	n_ports    = HCS_N_PORTS(hcs_params);
 
 	dbgp_printk("debug_port: %d\n", debug_port);
 	dbgp_printk("n_ports:    %d\n", n_ports);
+	dbgp_ehci_status("");
 
 	for (i = 1; i <= n_ports; i++) {
 		portsc = readl(&ehci_regs->port_status[i-1]);
@@ -523,138 +755,27 @@ try_next_port:
 		return -1;
 	}
 
-	loop = 250 * 1000;
-	/* Reset the EHCI controller */
-	cmd = readl(&ehci_regs->command);
-	cmd |= CMD_RESET;
-	writel(cmd, &ehci_regs->command);
-	do {
-		cmd = readl(&ehci_regs->command);
-	} while ((cmd & CMD_RESET) && (--loop > 0));
-
-	if (!loop) {
-		dbgp_printk("can not reset ehci\n");
-		return -1;
-	}
-	dbgp_printk("ehci reset done\n");
-
-	/* Claim ownership, but do not enable yet */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_OWNER;
-	ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
-	writel(ctrl, &ehci_debug->control);
-	udelay(1);
-
-	/* Start the ehci running */
-	cmd = readl(&ehci_regs->command);
-	cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
-	cmd |= CMD_RUN;
-	writel(cmd, &ehci_regs->command);
-
-	/* Ensure everything is routed to the EHCI */
-	writel(FLAG_CF, &ehci_regs->configured_flag);
-
-	/* Wait until the controller is no longer halted */
-	loop = 10;
-	do {
-		status = readl(&ehci_regs->status);
-		if (!(status & STS_HALT))
-			break;
-		udelay(1);
-	} while (--loop > 0);
-
-	if (!loop) {
-		dbgp_printk("ehci can not be started\n");
-		return -1;
+	/* Only reset the controller if it is not already in the
+	 * configured state */
+	if (!(readl(&ehci_regs->configured_flag) & FLAG_CF)) {
+		if (dbgp_ehci_controller_reset() != 0)
+			return -1;
+	} else {
+		dbgp_ehci_status("ehci skip - already configured");
 	}
-	dbgp_printk("ehci started\n");
 
-	/* Wait for a device to show up in the debug port */
-	ret = ehci_wait_for_port(debug_port);
-	if (ret < 0) {
-		dbgp_printk("No device found in debug port\n");
+	ret = dbgp_external_startup();
+	if (ret == -EIO)
 		goto next_debug_port;
-	}
-	dbgp_printk("ehci wait for port done\n");
-
-	/* Enable the debug port */
-	ctrl = readl(&ehci_debug->control);
-	ctrl |= DBGP_CLAIM;
-	writel(ctrl, &ehci_debug->control);
-	ctrl = readl(&ehci_debug->control);
-	if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
-		dbgp_printk("No device in debug port\n");
-		writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
-		goto err;
-	}
-	dbgp_printk("debug ported enabled\n");
 
-	/* Completely transfer the debug device to the debug controller */
-	portsc = readl(&ehci_regs->port_status[debug_port - 1]);
-	portsc &= ~PORT_PE;
-	writel(portsc, &ehci_regs->port_status[debug_port - 1]);
-
-	dbgp_mdelay(100);
-
-	/* Find the debug device and make it device number 127 */
-	for (devnum = 0; devnum <= 127; devnum++) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
-			&dbgp_desc, sizeof(dbgp_desc));
-		if (ret > 0)
-			break;
-	}
-	if (devnum > 127) {
-		dbgp_printk("Could not find attached debug device\n");
-		goto err;
-	}
 	if (ret < 0) {
-		dbgp_printk("Attached device is not a debug device\n");
-		goto err;
-	}
-	dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
-
-	/* Move the device to 127 if it isn't already there */
-	if (devnum != USB_DEBUG_DEVNUM) {
-		ret = dbgp_control_msg(devnum,
-			USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-			USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
-		if (ret < 0) {
-			dbgp_printk("Could not move attached device to %d\n",
-				USB_DEBUG_DEVNUM);
-			goto err;
-		}
-		devnum = USB_DEBUG_DEVNUM;
-		dbgp_printk("debug device renamed to 127\n");
-	}
-
-	/* Enable the debug interface */
-	ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
-		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
-		USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
-	if (ret < 0) {
-		dbgp_printk(" Could not enable the debug device\n");
-		goto err;
-	}
-	dbgp_printk("debug interface enabled\n");
-
-	/* Perform a small write to get the even/odd data state in sync
-	 */
-	ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
-	if (ret < 0) {
-		dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
-		goto err;
+		/* Things didn't work so remove my claim */
+		ctrl = readl(&ehci_debug->control);
+		ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
+		writel(ctrl, &ehci_debug->control);
+		return -1;
 	}
-	dbgp_printk("small write doned\n");
-
 	return 0;
-err:
-	/* Things didn't work so remove my claim */
-	ctrl = readl(&ehci_debug->control);
-	ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
-	writel(ctrl, &ehci_debug->control);
-	return -1;
 
 next_debug_port:
 	port_map_tried |= (1<<(debug_port - 1));
@@ -749,6 +870,7 @@ int __init early_dbgp_init(char *s)
 
 		return -1;
 	}
+	dbgp_ehci_status("early_init_complete");
 
 	return 0;
 }
@@ -758,9 +880,27 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n)
 	int chunk, ret;
 	char buf[DBGP_MAX_PACKET];
 	int use_cr = 0;
+	u32 cmd, ctrl;
+	int reset_run = 0;
 
-	if (!ehci_debug)
+	if (!ehci_debug || dbgp_not_safe)
 		return;
+
+	cmd = readl(&ehci_regs->command);
+	if (unlikely(!(cmd & CMD_RUN))) {
+		/* If the ehci controller is not in the run state do extended
+		 * checks to see if the acpi or some other initialization also
+		 * reset the ehci debug port */
+		ctrl = readl(&ehci_debug->control);
+		if (!(ctrl & DBGP_ENABLED)) {
+			dbgp_not_safe = 1;
+			dbgp_external_startup();
+		} else {
+			cmd |= CMD_RUN;
+			writel(cmd, &ehci_regs->command);
+			reset_run = 1;
+		}
+	}
 	while (n > 0) {
 		for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0;
 		     str++, chunk++, n--) {
@@ -775,8 +915,15 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n)
 				use_cr = 0;
 			buf[chunk] = *str;
 		}
-		ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
-			dbgp_endpoint_out, buf, chunk);
+		if (chunk > 0) {
+			ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
+				      dbgp_endpoint_out, buf, chunk);
+		}
+	}
+	if (unlikely(reset_run)) {
+		cmd = readl(&ehci_regs->command);
+		cmd &= ~CMD_RUN;
+		writel(cmd, &ehci_regs->command);
 	}
 }
 
@@ -786,4 +933,3 @@ struct console early_dbgp_console = {
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };
-
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 0e22b5f..e1346fd 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -163,4 +163,9 @@ extern int __init early_dbgp_init(char *s);
 extern struct console early_dbgp_console;
 #endif /* CONFIG_EARLY_PRINTK_DBGP */
 
+#ifdef CONFIG_EARLY_PRINTK_DBGP
+/* Call backs from ehci host driver to ehci debug driver */
+extern int dbgp_external_startup(void);
+#endif
+
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

[PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

If the EHCI debug port is initialized and in use, the EHCI host
controller driver must follow two rules.

1) If the EHCI host driver issues a controller reset, the debug
   controller driver re-initialization must get called after the reset
   is completed.

2) The EHCI host driver should ignore any requests to the physical
   EHCI debug port when the EHCI debug port is in use.

The code to check for the debug port was moved from ehci_pci_reinit()
to ehci_pci_setup because it must get called prior to ehci_reset()
which will clear the debug port registers.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/usb/early/ehci-dbgp.c |   23 +++++++++++++++++++++++
 drivers/usb/host/ehci-hcd.c   |    8 ++++++++
 drivers/usb/host/ehci-hub.c   |   10 ++++++++++
 drivers/usb/host/ehci-pci.c   |   39 +++++++++++++++++++--------------------
 include/linux/usb/ehci_def.h  |   10 ++++++++++
 5 files changed, 70 insertions(+), 20 deletions(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 06e05ea..b88cb65 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -933,3 +933,26 @@ struct console early_dbgp_console = {
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };
+
+int dbgp_reset_prep(void)
+{
+	u32 ctrl;
+
+	dbgp_not_safe = 1;
+	if (!ehci_debug)
+		return 0;
+
+	if (early_dbgp_console.index != -1 &&
+		!(early_dbgp_console.flags & CON_BOOT))
+		return 1;
+	/* This means the console is not initialized, or should get
+	 * shutdown so as to allow for reuse of the usb device, which
+	 * means it is time to shutdown the usb debug port. */
+	ctrl = readl(&ehci_debug->control);
+	if (ctrl & DBGP_ENABLED) {
+		ctrl &= ~(DBGP_CLAIM);
+		writel(ctrl, &ehci_debug->control);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dbgp_reset_prep);
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 7d03549..d4d4974 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -239,6 +239,11 @@ static int ehci_reset (struct ehci_hcd *ehci)
 	int	retval;
 	u32	command = ehci_readl(ehci, &ehci->regs->command);
 
+	/* If the EHCI debug controller is active, special care must be
+	 * taken before and after a host controller reset */
+	if (ehci->debug && !dbgp_reset_prep())
+		ehci->debug = NULL;
+
 	command |= CMD_RESET;
 	dbg_cmd (ehci, "reset", command);
 	ehci_writel(ehci, command, &ehci->regs->command);
@@ -253,6 +258,9 @@ static int ehci_reset (struct ehci_hcd *ehci)
 	if (ehci_is_TDI(ehci))
 		tdi_reset (ehci);
 
+	if (ehci->debug)
+		dbgp_external_startup();
+
 	return retval;
 }
 
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index f46ad27..149beb8 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -816,6 +816,15 @@ static int ehci_hub_control (
 	case SetPortFeature:
 		selector = wIndex >> 8;
 		wIndex &= 0xff;
+		if (unlikely(ehci->debug)) {
+			/* If the debug port is active any port
+			 * feature requests should get denied */
+			if ((readl(&ehci->debug->control) & DBGP_ENABLED) &&
+			    wIndex == HCS_DEBUG_PORT(ehci->hcs_params)) {
+				retval = -ENODEV;
+				goto error_exit;
+			}
+		}
 		if (!wIndex || wIndex > ports)
 			goto error;
 		wIndex--;
@@ -894,6 +903,7 @@ error:
 		/* "stall" on error */
 		retval = -EPIPE;
 	}
+error_exit:
 	spin_unlock_irqrestore (&ehci->lock, flags);
 	return retval;
 }
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index c2f1b7d..ea36c1c 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -27,28 +27,8 @@
 /* called after powerup, by probe or system-pm "wakeup" */
 static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev)
 {
-	u32			temp;
 	int			retval;
 
-	/* optional debug port, normally in the first BAR */
-	temp = pci_find_capability(pdev, 0x0a);
-	if (temp) {
-		pci_read_config_dword(pdev, temp, &temp);
-		temp >>= 16;
-		if ((temp & (3 << 13)) == (1 << 13)) {
-			temp &= 0x1fff;
-			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
-			temp = ehci_readl(ehci, &ehci->debug->control);
-			ehci_info(ehci, "debug port %d%s\n",
-				HCS_DEBUG_PORT(ehci->hcs_params),
-				(temp & DBGP_ENABLED)
-					? " IN USE"
-					: "");
-			if (!(temp & DBGP_ENABLED))
-				ehci->debug = NULL;
-		}
-	}
-
 	/* we expect static quirk code to handle the "extended capabilities"
 	 * (currently just BIOS handoff) allowed starting with EHCI 0.96
 	 */
@@ -192,6 +172,25 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 		break;
 	}
 
+	/* optional debug port, normally in the first BAR */
+	temp = pci_find_capability(pdev, 0x0a);
+	if (temp) {
+		pci_read_config_dword(pdev, temp, &temp);
+		temp >>= 16;
+		if ((temp & (3 << 13)) == (1 << 13)) {
+			temp &= 0x1fff;
+			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
+			temp = ehci_readl(ehci, &ehci->debug->control);
+			ehci_info(ehci, "debug port %d%s\n",
+				HCS_DEBUG_PORT(ehci->hcs_params),
+				(temp & DBGP_ENABLED)
+					? " IN USE"
+					: "");
+			if (!(temp & DBGP_ENABLED))
+				ehci->debug = NULL;
+		}
+	}
+
 	ehci_reset(ehci);
 
 	/* at least the Genesys GL880S needs fixup here */
diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index e1346fd..7290daf 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -166,6 +166,16 @@ extern struct console early_dbgp_console;
 #ifdef CONFIG_EARLY_PRINTK_DBGP
 /* Call backs from ehci host driver to ehci debug driver */
 extern int dbgp_external_startup(void);
+extern int dbgp_reset_prep(void);
+#else
+static inline int dbgp_reset_prep(void)
+{
+	return 1;
+}
+static inline int dbgp_external_startup(void)
+{
+	return -1;
+}
 #endif
 
 #endif /* __LINUX_USB_EHCI_DEF_H */
-- 
1.6.0.3.523.g304d0

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Alan Stern]

On Fri, 31 Jul 2009, Jason Wessel wrote:

> If the EHCI debug port is initialized and in use, the EHCI host
> controller driver must follow two rules.
> 
> 1) If the EHCI host driver issues a controller reset, the debug
>    controller driver re-initialization must get called after the reset
>    is completed.
> 
> 2) The EHCI host driver should ignore any requests to the physical
>    EHCI debug port when the EHCI debug port is in use.
> 
> The code to check for the debug port was moved from ehci_pci_reinit()
> to ehci_pci_setup because it must get called prior to ehci_reset()
> which will clear the debug port registers.

> --- a/drivers/usb/host/ehci-hub.c
> +++ b/drivers/usb/host/ehci-hub.c
> @@ -816,6 +816,15 @@ static int ehci_hub_control (
>  	case SetPortFeature:
>  		selector = wIndex >> 8;
>  		wIndex &= 0xff;
> +		if (unlikely(ehci->debug)) {

Don't you need a similar test for ClearPortFeature?  Or does that not
matter?

> +			/* If the debug port is active any port
> +			 * feature requests should get denied */
> +			if ((readl(&ehci->debug->control) & DBGP_ENABLED) &&
> +			    wIndex == HCS_DEBUG_PORT(ehci->hcs_params)) {

The order of the two tests here should be reversed, to avoid an 
unnecessary I/O access in the common case.

> +				retval = -ENODEV;
> +				goto error_exit;

This is the wrong return value.  You should return -EPIPE, i.e., goto
error instead of error_exit.

> +			}
> +		}
>  		if (!wIndex || wIndex > ports)
>  			goto error;
>  		wIndex--;
> @@ -894,6 +903,7 @@ error:
>  		/* "stall" on error */
>  		retval = -EPIPE;
>  	}
> +error_exit:

And then this new label isn't needed.

>  	spin_unlock_irqrestore (&ehci->lock, flags);
>  	return retval;
>  }

Alan Stern

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

Alan Stern wrote:
> On Fri, 31 Jul 2009, Jason Wessel wrote:
>
>> If the EHCI debug port is initialized and in use, the EHCI host
>> controller driver must follow two rules.
>>
>> 1) If the EHCI host driver issues a controller reset, the debug
>>    controller driver re-initialization must get called after the reset
>>    is completed.
>>
>> 2) The EHCI host driver should ignore any requests to the physical
>>    EHCI debug port when the EHCI debug port is in use.
>>
>> The code to check for the debug port was moved from ehci_pci_reinit()
>> to ehci_pci_setup because it must get called prior to ehci_reset()
>> which will clear the debug port registers.
>> --- a/drivers/usb/host/ehci-hub.c
>> +++ b/drivers/usb/host/ehci-hub.c
>> @@ -816,6 +816,15 @@ static int ehci_hub_control (
>>      case SetPortFeature:
>>          selector = wIndex >> 8;
>>          wIndex &= 0xff;
>> +        if (unlikely(ehci->debug)) {
>
> Don't you need a similar test for ClearPortFeature?  Or does that not
> matter?

I guess it depends if the user space tries to poke it, and then
perhaps yes.  Do you know if that would be the case?

The rejection of the SetPortFeature at this level prevents the generic
hub code from activating the port, in so far as all my tests cases
show.

Given that it won't hurt anything to have the same code in the
ClearPortFeature I can put it in.

>
>> +            /* If the debug port is active any port
>> +             * feature requests should get denied */
>> +            if ((readl(&ehci->debug->control) & DBGP_ENABLED) &&
>> +                wIndex == HCS_DEBUG_PORT(ehci->hcs_params)) {
>
> The order of the two tests here should be reversed, to avoid an
> unnecessary I/O access in the common case.
>

Yes.  I agree here.


>> +                retval = -ENODEV;
>> +                goto error_exit;
>
> This is the wrong return value.  You should return -EPIPE, i.e., goto
> error instead of error_exit.


Do you have some insight as to how to account for the not using the
port another way?  If I return -EPIPE, vs -ENODEV.  The kernel code
does very different things.  I chose -ENODEV based on the results
below.

With -ENODEV the kernel emits the following when trying to probe the
usb port with the dbgp device.


hub 2-0:1.0: cannot reset port 1 (err = -19)
hub 2-0:1.0: cannot reset port 1 (err = -19)
hub 2-0:1.0: cannot reset port 1 (err = -19)
hub 2-0:1.0: cannot reset port 1 (err = -19)
hub 2-0:1.0: unable to enumerate USB device on port 1


With returning -EPIPE you get this result.

hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
USB Serial support registered for generic
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: cannot reset port 1 (err = -32)
hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 2-0:1.0: unable to enumerate USB device on port 1


I was looking for the easiest maintainable approach to disabling the
physical port from getting reset by the HCD hub driver, which does
different things depending on the error code that is passed back.

Knowing what happens with -EPIPE, would you still prefer it to be
changed that way?  Another possibility here is to implement the
restriction on the port reset another way, if you have any
suggestions.

In general folks may not need to use earlyprintk=dbpg,keep too often,
but it sure is nice when it works because you can use it as a full
console monitoring device after the /sbin/init handoff, including
debugging USB printk's because the usb debug controller driver is
completely separate.


Jason.

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Alan Stern]

On Fri, 31 Jul 2009, Jason Wessel wrote:

> >> --- a/drivers/usb/host/ehci-hub.c
> >> +++ b/drivers/usb/host/ehci-hub.c
> >> @@ -816,6 +816,15 @@ static int ehci_hub_control (
> >>      case SetPortFeature:
> >>          selector = wIndex >> 8;
> >>          wIndex &= 0xff;
> >> +        if (unlikely(ehci->debug)) {
> >
> > Don't you need a similar test for ClearPortFeature?  Or does that not
> > matter?
> 
> I guess it depends if the user space tries to poke it, and then
> perhaps yes.  Do you know if that would be the case?

It's extremely unlikely.

> The rejection of the SetPortFeature at this level prevents the generic
> hub code from activating the port, in so far as all my tests cases
> show.
> 
> Given that it won't hurt anything to have the same code in the
> ClearPortFeature I can put it in.

It probably doesn't matter.

> >> +                retval = -ENODEV;
> >> +                goto error_exit;
> >
> > This is the wrong return value.  You should return -EPIPE, i.e., goto
> > error instead of error_exit.
> 
> 
> Do you have some insight as to how to account for the not using the
> port another way?  If I return -EPIPE, vs -ENODEV.  The kernel code
> does very different things.  I chose -ENODEV based on the results
> below.
> 
> With -ENODEV the kernel emits the following when trying to probe the
> usb port with the dbgp device.
> 
> 
> hub 2-0:1.0: cannot reset port 1 (err = -19)
> hub 2-0:1.0: cannot reset port 1 (err = -19)
> hub 2-0:1.0: cannot reset port 1 (err = -19)
> hub 2-0:1.0: cannot reset port 1 (err = -19)
> hub 2-0:1.0: unable to enumerate USB device on port 1
> 
> 
> With returning -EPIPE you get this result.
> 
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> USB Serial support registered for generic
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: cannot reset port 1 (err = -32)
> hub 2-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
> hub 2-0:1.0: unable to enumerate USB device on port 1
> 
> 
> I was looking for the easiest maintainable approach to disabling the
> physical port from getting reset by the HCD hub driver, which does
> different things depending on the error code that is passed back.

Evidently I was wrong; -ENODEV is better.

> Knowing what happens with -EPIPE, would you still prefer it to be
> changed that way?  Another possibility here is to implement the
> restriction on the port reset another way, if you have any
> suggestions.
> 
> In general folks may not need to use earlyprintk=dbpg,keep too often,
> but it sure is nice when it works because you can use it as a full
> console monitoring device after the /sbin/init handoff, including
> debugging USB printk's because the usb debug controller driver is
> completely separate.

What happens across a system suspend?

Alan Stern

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

Alan Stern wrote:
> What happens across a system suspend?
>
>   

I assume you mean as a test case:

echo -n mem > /sys/power/state

The dbgp device goes away entirely, when used with
earlyprintk=dbgp,keep.  But there is a way to fix it reasonably
easily.  Perhaps you might ack this resume patch, if you agree?

Jason.

---
From: Jason Wessel <jason.wessel@windriver.com>
Subject: [PATCH] ehci-dbgp,ehci: Allow dbpg to work with suspend/resume

In order for the dbgp driver to survive suspend/resume, on every ehci
resume operation the debug controller must get re-initialized.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>

---
 drivers/usb/host/ehci-hub.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -204,6 +204,13 @@ static int ehci_bus_resume (struct usb_h
 		return -ESHUTDOWN;
 	}
 
+	if (unlikely(ehci->debug)) {
+		if (ehci->debug && !dbgp_reset_prep())
+			ehci->debug = NULL;
+		else
+			dbgp_external_startup();
+	}
+
 	/* Ideally and we've got a real resume here, and no port's power
 	 * was lost.  (For PCI, that means Vaux was maintained.)  But we
 	 * could instead be restoring a swsusp snapshot -- so that BIOS was

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Alan Stern]

On Fri, 31 Jul 2009, Jason Wessel wrote:

> Alan Stern wrote:
> > What happens across a system suspend?
> >
> >   
> 
> I assume you mean as a test case:
> 
> echo -n mem > /sys/power/state
> 
> The dbgp device goes away entirely, when used with
> earlyprintk=dbgp,keep.  But there is a way to fix it reasonably
> easily.  Perhaps you might ack this resume patch, if you agree?
> 
> Jason.
> 
> ---
> From: Jason Wessel <jason.wessel@windriver.com>
> Subject: [PATCH] ehci-dbgp,ehci: Allow dbpg to work with suspend/resume
> 
> In order for the dbgp driver to survive suspend/resume, on every ehci
> resume operation the debug controller must get re-initialized.
> 
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> Cc: Greg KH <gregkh@suse.de>
> Cc: Alan Stern <stern@rowland.harvard.edu>
> Cc: dbrownell@users.sourceforge.net
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Yinghai Lu <yinghai@kernel.org>
> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
> 
> ---
>  drivers/usb/host/ehci-hub.c |    6 ++++++
>  1 file changed, 6 insertions(+)
> 
> --- a/drivers/usb/host/ehci-hub.c
> +++ b/drivers/usb/host/ehci-hub.c
> @@ -204,6 +204,13 @@ static int ehci_bus_resume (struct usb_h
>  		return -ESHUTDOWN;
>  	}
>  
> +	if (unlikely(ehci->debug)) {
> +		if (ehci->debug && !dbgp_reset_prep())
> +			ehci->debug = NULL;
> +		else
> +			dbgp_external_startup();
> +	}
> +
>  	/* Ideally and we've got a real resume here, and no port's power
>  	 * was lost.  (For PCI, that means Vaux was maintained.)  But we
>  	 * could instead be restoring a swsusp snapshot -- so that BIOS was

It looks fine to me.  Would you perhaps want to make dbgp_reset_prep()
automatically call dbgp_external_startup() on success so that ehci-hcd
doesn't have to?

Alan Stern

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Jason Wessel]

Alan Stern wrote:
> On Fri, 31 Jul 2009, Jason Wessel wrote:
>
>   
>> Alan Stern wrote:
>>     
>>> What happens across a system suspend?
>>>
>>>   
>>>       
>> I assume you mean as a test case:
>>
>> echo -n mem > /sys/power/state
>>
>> The dbgp device goes away entirely, when used with
>> earlyprintk=dbgp,keep.  But there is a way to fix it reasonably
>> easily.  Perhaps you might ack this resume patch, if you agree?
>>
>> Jason.
>>
>> ---
>> From: Jason Wessel <jason.wessel@windriver.com>
>> Subject: [PATCH] ehci-dbgp,ehci: Allow dbpg to work with suspend/resume
>>
>> In order for the dbgp driver to survive suspend/resume, on every ehci
>> resume operation the debug controller must get re-initialized.
>>
>> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
>> Cc: Greg KH <gregkh@suse.de>
>> Cc: Alan Stern <stern@rowland.harvard.edu>
>> Cc: dbrownell@users.sourceforge.net
>> Cc: Ingo Molnar <mingo@elte.hu>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Yinghai Lu <yinghai@kernel.org>
>> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
>>
>> ---
>>  drivers/usb/host/ehci-hub.c |    6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> --- a/drivers/usb/host/ehci-hub.c
>> +++ b/drivers/usb/host/ehci-hub.c
>> @@ -204,6 +204,13 @@ static int ehci_bus_resume (struct usb_h
>>  		return -ESHUTDOWN;
>>  	}
>>  
>> +	if (unlikely(ehci->debug)) {
>> +		if (ehci->debug && !dbgp_reset_prep())
>> +			ehci->debug = NULL;
>> +		else
>> +			dbgp_external_startup();
>> +	}
>> +
>>  	/* Ideally and we've got a real resume here, and no port's power
>>  	 * was lost.  (For PCI, that means Vaux was maintained.)  But we
>>  	 * could instead be restoring a swsusp snapshot -- so that BIOS was
>>     
>
> It looks fine to me.  Would you perhaps want to make dbgp_reset_prep()
> automatically call dbgp_external_startup() on success so that ehci-hcd
> doesn't have to?
>   

Unfortunately the dbgp_reset_prep() and dbgp_external_startup() have to
be separate for the hcd case because the ehci controller reset comes in
between.  If you don't call dbgp_reset_prep() first, the ehci controller
can hang the system for the "ehci debug controller timeout death
period", or you can end up with undefined behavior if the ehci debug
controller is accessed while the reset code is being processed.

The dbgp_reset_prep() puts the ehci debug controller/driver into a safe
state until after the reset is done, and then the
dbgp_external_startup() re-initializes the ehci debug controller.

For the case of the power suspend, the ehci debug controller appeared to
be usable all the way to the time the power got yanked.  For the resume
operation, the debug controller driver sees that from the resume state
that the enable bit is off and doesn't try to use the device until
dbgp_reset_prep() and dbgp_external_reset() are called in sequence.

The dbgp_reset_prep() has to get called in resume to handle the case
where you remove the dbgp device while suspended and before you resumed
such that it won't hang the kernel.

Jason.

Re: [PATCH 07/10] ehci-dbgp,ehci: Allow early or late use of the dbgp device

[Greg KH]

On Fri, Jul 31, 2009 at 10:07:10AM -0500, Jason Wessel wrote:
> If the EHCI debug port is initialized and in use, the EHCI host
> controller driver must follow two rules.

As there was some discussion of this patch, do you have a new one?

I've applied the first 6 in the series, care to resend 7-10 with the
proper versions?

thanks,

greg k-h