[U-Boot] [PATCH 2/2] ehci-hcd.c, musb_core, usb.h: Add USB_DMA_MINALIGN define for cache alignment

Marek Vasut
2012-07-08T03:08:15Z

From: Tom Rini <trini@ti.com>

The USB spec says that 32 bytes is the minimum required alignment.
However on some platforms we have a larger minimum requirement for cache
coherency. In those cases, use that value rather than the USB spec
minimum. We add a cpp check to <usb.h> to define USB_DMA_MINALIGN and
make use of it in ehci-hcd.c and musb_core.h. We cannot use MAX() here
as we are not allowed to have tests inside of align(...).

Signed-off-by: Tom Rini <trini@ti.com>
[ilya.yanok]: fix size alignment, drop (incorrect) rounding
when invalidating the buffer. If we got unaligned buffer from the
upper layer -- that's definetely a bug so it's good to buzz
about it. But we have to align the buffer length -- upper layers
should take care to reserve enough space.
Signed-off-by: Ilya Yanok <ilya.yanok@cogentembedded.com>
[marek.vasut]: introduce some crazy macro voodoo
Signed-off-by: Marek Vasut <marex@denx.de>
---
drivers/usb/host/ehci-hcd.c | 81 ++++++++++++++++++++++++------------------
drivers/usb/musb/musb_core.h | 2 +-
include/usb.h | 10 ++++++
3 files changed, 57 insertions(+), 36 deletions(-)

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 04300be..5199560 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -34,7 +34,10 @@ struct ehci_hccr *hccr; /* R/O registers, not need for volatile */
volatile struct ehci_hcor *hcor;

static uint16_t portreset;
-static struct QH qh_list __attribute__((aligned(32)));
+DEFINE_CACHE_ALIGN_BUFFER(struct QH, qh_list, 1);
+
+#define ALIGN_END_ADDR(type, ptr, size) \
+ ((uint32_t)(ptr) + roundup((size) * sizeof(type), USB_DMA_MINALIGN))

static struct descriptor {
struct usb_hub_descriptor hub;
@@ -172,13 +175,13 @@ static int ehci_td_buffer(struct qTD *td, void *buf, size_t sz)
{
uint32_t delta, next;
uint32_t addr = (uint32_t)buf;
- size_t rsz = roundup(sz, 32);
+ size_t rsz = roundup(sz, USB_DMA_MINALIGN);
int idx;

if (sz != rsz)
debug("EHCI-HCD: Misaligned buffer size (%08x)\n", sz);

- if (addr & 31)
+ if (addr != ALIGN(addr, USB_DMA_MINALIGN))
debug("EHCI-HCD: Misaligned buffer address (%p)\n", buf);

idx = 0;
@@ -207,8 +210,8 @@ static int
ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
int length, struct devrequest *req)
{
- static struct QH qh __attribute__((aligned(32)));
- static struct qTD qtd[3] __attribute__((aligned (32)));
+ ALLOC_CACHE_ALIGN_BUFFER(struct QH, qh, 1);
+ ALLOC_CACHE_ALIGN_BUFFER(struct qTD, qtd, 3);
int qtd_counter = 0;

volatile struct qTD *vtd;
@@ -229,8 +232,8 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
le16_to_cpu(req->value), le16_to_cpu(req->value),
le16_to_cpu(req->index));

- memset(&qh, 0, sizeof(struct QH));
- memset(qtd, 0, sizeof(qtd));
+ memset(qh, 0, sizeof(struct QH));
+ memset(qtd, 0, 3 * sizeof(*qtd));

toggle = usb_gettoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe));

@@ -244,7 +247,7 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
* qh_overlay.qt_next ...... 13-10 H
* - qh_overlay.qt_altnext
*/
- qh.qh_link = cpu_to_hc32((uint32_t)&qh_list | QH_LINK_TYPE_QH);
+ qh->qh_link = cpu_to_hc32((uint32_t)qh_list | QH_LINK_TYPE_QH);
c = (usb_pipespeed(pipe) != USB_SPEED_HIGH &&
usb_pipeendpoint(pipe) == 0) ? 1 : 0;
endpt = (8 << 28) |
@@ -255,14 +258,14 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
(usb_pipespeed(pipe) << 12) |
(usb_pipeendpoint(pipe) << 8) |
(0 << 7) | (usb_pipedevice(pipe) << 0);
- qh.qh_endpt1 = cpu_to_hc32(endpt);
+ qh->qh_endpt1 = cpu_to_hc32(endpt);
endpt = (1 << 30) |
(dev->portnr << 23) |
(dev->parent->devnum << 16) | (0 << 8) | (0 << 0);
- qh.qh_endpt2 = cpu_to_hc32(endpt);
- qh.qh_overlay.qt_next = cpu_to_hc32(QT_NEXT_TERMINATE);
+ qh->qh_endpt2 = cpu_to_hc32(endpt);
+ qh->qh_overlay.qt_next = cpu_to_hc32(QT_NEXT_TERMINATE);

- tdp = &qh.qh_overlay.qt_next;
+ tdp = &qh->qh_overlay.qt_next;

if (req != NULL) {
/*
@@ -340,13 +343,13 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
tdp = &qtd[qtd_counter++].qt_next;
}

- qh_list.qh_link = cpu_to_hc32((uint32_t)&qh | QH_LINK_TYPE_QH);
+ qh_list->qh_link = cpu_to_hc32((uint32_t)qh | QH_LINK_TYPE_QH);

/* Flush dcache */
- flush_dcache_range((uint32_t)&qh_list,
- (uint32_t)&qh_list + sizeof(struct QH));
- flush_dcache_range((uint32_t)&qh, (uint32_t)&qh + sizeof(struct QH));
- flush_dcache_range((uint32_t)qtd, (uint32_t)qtd + sizeof(qtd));
+ flush_dcache_range((uint32_t)qh_list,
+ ALIGN_END_ADDR(struct QH, qh_list, 1));
+ flush_dcache_range((uint32_t)qh, ALIGN_END_ADDR(struct QH, qh, 1));
+ flush_dcache_range((uint32_t)qtd, ALIGN_END_ADDR(struct qTD, qtd, 3));

usbsts = ehci_readl(&hcor->or_usbsts);
ehci_writel(&hcor->or_usbsts, (usbsts & 0x3f));
@@ -369,12 +372,12 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
timeout = USB_TIMEOUT_MS(pipe);
do {
/* Invalidate dcache */
- invalidate_dcache_range((uint32_t)&qh_list,
- (uint32_t)&qh_list + sizeof(struct QH));
- invalidate_dcache_range((uint32_t)&qh,
- (uint32_t)&qh + sizeof(struct QH));
+ invalidate_dcache_range((uint32_t)qh_list,
+ ALIGN_END_ADDR(struct QH, qh_list, 1));
+ invalidate_dcache_range((uint32_t)qh,
+ ALIGN_END_ADDR(struct QH, qh, 1));
invalidate_dcache_range((uint32_t)qtd,
- (uint32_t)qtd + sizeof(qtd));
+ ALIGN_END_ADDR(struct qTD, qtd, 3));

token = hc32_to_cpu(vtd->qt_token);
if (!(token & 0x80))
@@ -382,9 +385,17 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
WATCHDOG_RESET();
} while (get_timer(ts) < timeout);

- /* Invalidate the memory area occupied by buffer */
- invalidate_dcache_range(((uint32_t)buffer & ~31),
- ((uint32_t)buffer & ~31) + roundup(length, 32));
+ /*
+ * Invalidate the memory area occupied by buffer
+ * Don't try to fix the buffer alignment, if it isn't properly
+ * aligned it's upper layer's fault so let invalidate_dcache_range()
+ * vow about it. But we have to fix the length as it's actual
+ * transfer length and can be unaligned. This is potentially
+ * dangerous operation, it's responsibility of the calling
+ * code to make sure enough space is reserved.
+ */
+ invalidate_dcache_range((uint32_t)buffer,
+ ALIGN_END_ADDR(u8, buffer, length));

/* Check that the TD processing happened */
if (token & 0x80) {
@@ -403,9 +414,9 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer,
goto fail;
}

- qh_list.qh_link = cpu_to_hc32((uint32_t)&qh_list | QH_LINK_TYPE_QH);
+ qh_list->qh_link = cpu_to_hc32((uint32_t)qh_list | QH_LINK_TYPE_QH);

- token = hc32_to_cpu(qh.qh_overlay.qt_token);
+ token = hc32_to_cpu(qh->qh_overlay.qt_token);
if (!(token & 0x80)) {
debug("TOKEN=%#x\n", token);
switch (token & 0xfc) {
@@ -733,16 +744,16 @@ int usb_lowlevel_init(void)
#endif

/* Set head of reclaim list */
- memset(&qh_list, 0, sizeof(qh_list));
- qh_list.qh_link = cpu_to_hc32((uint32_t)&qh_list | QH_LINK_TYPE_QH);
- qh_list.qh_endpt1 = cpu_to_hc32((1 << 15) | (USB_SPEED_HIGH << 12));
- qh_list.qh_curtd = cpu_to_hc32(QT_NEXT_TERMINATE);
- qh_list.qh_overlay.qt_next = cpu_to_hc32(QT_NEXT_TERMINATE);
- qh_list.qh_overlay.qt_altnext = cpu_to_hc32(QT_NEXT_TERMINATE);
- qh_list.qh_overlay.qt_token = cpu_to_hc32(0x40);
+ memset(qh_list, 0, sizeof(*qh_list));
+ qh_list->qh_link = cpu_to_hc32((uint32_t)qh_list | QH_LINK_TYPE_QH);
+ qh_list->qh_endpt1 = cpu_to_hc32((1 << 15) | (USB_SPEED_HIGH << 12));
+ qh_list->qh_curtd = cpu_to_hc32(QT_NEXT_TERMINATE);
+ qh_list->qh_overlay.qt_next = cpu_to_hc32(QT_NEXT_TERMINATE);
+ qh_list->qh_overlay.qt_altnext = cpu_to_hc32(QT_NEXT_TERMINATE);
+ qh_list->qh_overlay.qt_token = cpu_to_hc32(0x40);

/* Set async. queue head pointer. */
- ehci_writel(&hcor->or_asynclistaddr, (uint32_t)&qh_list);
+ ehci_writel(&hcor->or_asynclistaddr, (uint32_t)qh_list);

reg = ehci_readl(&hccr->cr_hcsparams);
descriptor.hub.bNbrPorts = HCS_N_PORTS(reg);
diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
index a8adcce..e914369 100644
--- a/drivers/usb/musb/musb_core.h
+++ b/drivers/usb/musb/musb_core.h
@@ -145,7 +145,7 @@ struct musb_regs {
struct musb_epN_regs epN;
} ep[16];

-} __attribute__((packed, aligned(32)));
+} __attribute__((packed, aligned(USB_DMA_MINALIGN)));
#endif

/*
diff --git a/include/usb.h b/include/usb.h
index 6da91e7..ba3d169 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -29,6 +29,16 @@
#include <usb_defs.h>
#include <usbdescriptors.h>

+/*
+ * The EHCI spec says that we must align to at least 32 bytes. However,
+ * some platforms require larger alignment.
+ */
+#if ARCH_DMA_MINALIGN > 32
+#define USB_DMA_MINALIGN ARCH_DMA_MINALIGN
+#else
+#define USB_DMA_MINALIGN 32
+#endif
+
/* Everything is aribtrary */
#define USB_ALTSETTINGALLOC 4
#define USB_MAXALTSETTING 128 /* Hard limit */
--
1.7.10.4