Re: [PATCH] set altix preferred console

Mark Maule
2005-10-12T18:55:02Z

New version of Greg's original patch per review comments from Bjorn:

Fix default VGA console on SN platforms. Since SN firmware does not pass
enough ACPI information to identify VGA cards and the associated legacy IO/MEM
addresses, we rely on the EFI PCDP table. Since the linux pcdp driver is
optional (and overridden if console= directives are used) SN duplicates a
portion of the pcdp scan code to identify if there is a usable console VGA
adapter.

To avoid also dup'ing PCDP structures, drivers/firmware/pcdp.h is moved to
include/linux/pcdp.h.

Signed-off-by: Mark Maule <maule@sgi.com>

Index: vga/arch/ia64/sn/kernel/setup.c
=================================--- vga.orig/arch/ia64/sn/kernel/setup.c 2005-10-12 10:36:40.914797412 -0500
+++ vga/arch/ia64/sn/kernel/setup.c 2005-10-12 11:50:44.543433497 -0500
@@ -30,6 +30,8 @@
#include <linux/root_dev.h>
#include <linux/nodemask.h>
#include <linux/pm.h>
+#include <linux/efi.h>
+#include <linux/pcdp.h>

#include <asm/io.h>
#include <asm/sal.h>
@@ -242,6 +244,48 @@
}
}

+static void
+sn_scan_pcdp(void)
+{
+ u8 *bp;
+ struct pcdp *pcdp;
+ struct pcdp_device device;
+ struct pcdp_if_pci if_pci;
+ extern struct efi efi;
+
+ pcdp = efi.hcdp;
+ if (! pcdp)
+ return; /* no hcdp/pcdp table */
+
+ if (pcdp->rev < 3)
+ return; /* only support PCDP (rev >= 3) */
+
+ for (bp = (u8 *)&pcdp->uart[pcdp->num_uarts];
+ bp < (u8 *)pcdp + pcdp->length;
+ bp += device.length) {
+ memcpy(&device, bp, sizeof(device));
+ if (! (device.flags & PCDP_PRIMARY_CONSOLE))
+ continue; /* not primary console */
+
+ if (device.type != PCDP_CONSOLE_VGA)
+ continue; /* not VGA descriptor */
+
+ memcpy(&if_pci, bp+sizeof(device), sizeof(if_pci));
+ if (if_pci.interconnect != PCDP_IF_PCI)
+ continue; /* not PCI interconnect */
+
+ if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
+ vga_console_iobase + if_pci.ioport_tra | __IA64_UNCACHED_OFFSET;
+
+ if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
+ vga_console_membase + if_pci.mmio_tra | __IA64_UNCACHED_OFFSET;
+
+ break; /* once we find the primary, we're done */
+ }
+}
+
/**
* sn_setup - SN platform setup routine
* @cmdline_p: kernel command line
@@ -263,16 +307,35 @@

#if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
/*
- * If there was a primary vga adapter identified through the
- * EFI PCDP table, make it the preferred console. Otherwise
- * zero out conswitchp.
+ * Handle SN vga console.
+ *
+ * SN systems do not have enough ACPI table information
+ * being passed from prom to identify VGA adapters and the legacy
+ * addresses to access them. Until that is done, SN systems rely
+ * on the PCDP table to identify the primary VGA console if one
+ * exists.
+ *
+ * However, kernel PCDP support is optional, and even if it is built
+ * into the kernel, it will not be used if the boot cmdline contains
+ * console= directives.
+ *
+ * So, to work around this mess, we duplicate some of the PCDP code
+ * here so that the primary VGA console (as defined by PCDP) will
+ * work on SN systems even if a different console (e.g. serial) is
+ * selected on the boot line (or CONFIG_EFI_PCDP is off).
*/

+ if (! vga_console_membase)
+ sn_scan_pcdp();
+
if (vga_console_membase) {
/* usable vga ... make tty0 the preferred default console */
- add_preferred_console("tty", 0, NULL);
+ if (!strstr(*cmdline_p, "console="))
+ add_preferred_console("tty", 0, NULL);
} else {
printk(KERN_DEBUG "SGI: Disabling VGA console\n");
+ if (!strstr(*cmdline_p, "console="))
+ add_preferred_console("ttySG", 0, NULL);
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#else
Index: vga/drivers/firmware/pcdp.c
=================================--- vga.orig/drivers/firmware/pcdp.c 2005-10-12 10:36:40.915773877 -0500
+++ vga/drivers/firmware/pcdp.c 2005-10-12 10:43:38.156192381 -0500
@@ -16,8 +16,8 @@
#include <linux/console.h>
#include <linux/efi.h>
#include <linux/serial.h>
+#include <linux/pcdp.h>
#include <asm/vga.h>
-#include "pcdp.h"

static int __init
setup_serial_console(struct pcdp_uart *uart)
Index: vga/drivers/firmware/pcdp.h
=================================--- vga.orig/drivers/firmware/pcdp.h 2005-10-12 10:36:40.914797412 -0500
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,111 +0,0 @@
-/*
- * Definitions for PCDP-defined console devices
- *
- * v1.0a: http://www.dig64.org/specifications/DIG64_HCDPv10a_01.pdf
- * v2.0: http://www.dig64.org/specifications/DIG64_PCDPv20.pdf
- *
- * (c) Copyright 2002, 2004 Hewlett-Packard Development Company, L.P.
- * Khalid Aziz <khalid.aziz@hp.com>
- * Bjorn Helgaas <bjorn.helgaas@hp.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#define PCDP_CONSOLE 0
-#define PCDP_DEBUG 1
-#define PCDP_CONSOLE_OUTPUT 2
-#define PCDP_CONSOLE_INPUT 3
-
-#define PCDP_UART (0 << 3)
-#define PCDP_VGA (1 << 3)
-#define PCDP_USB (2 << 3)
-
-/* pcdp_uart.type and pcdp_device.type */
-#define PCDP_CONSOLE_UART (PCDP_UART | PCDP_CONSOLE)
-#define PCDP_DEBUG_UART (PCDP_UART | PCDP_DEBUG)
-#define PCDP_CONSOLE_VGA (PCDP_VGA | PCDP_CONSOLE_OUTPUT)
-#define PCDP_CONSOLE_USB (PCDP_USB | PCDP_CONSOLE_INPUT)
-
-/* pcdp_uart.flags */
-#define PCDP_UART_EDGE_SENSITIVE (1 << 0)
-#define PCDP_UART_ACTIVE_LOW (1 << 1)
-#define PCDP_UART_PRIMARY_CONSOLE (1 << 2)
-#define PCDP_UART_IRQ (1 << 6) /* in pci_func for rev < 3 */
-#define PCDP_UART_PCI (1 << 7) /* in pci_func for rev < 3 */
-
-struct pcdp_uart {
- u8 type;
- u8 bits;
- u8 parity;
- u8 stop_bits;
- u8 pci_seg;
- u8 pci_bus;
- u8 pci_dev;
- u8 pci_func;
- u64 baud;
- struct acpi_generic_address addr;
- u16 pci_dev_id;
- u16 pci_vendor_id;
- u32 gsi;
- u32 clock_rate;
- u8 pci_prog_intfc;
- u8 flags;
- u16 conout_index;
- u32 reserved;
-} __attribute__((packed));
-
-#define PCDP_IF_PCI 1
-
-/* pcdp_if_pci.trans */
-#define PCDP_PCI_TRANS_IOPORT 0x02
-#define PCDP_PCI_TRANS_MMIO 0x01
-
-struct pcdp_if_pci {
- u8 interconnect;
- u8 reserved;
- u16 length;
- u8 segment;
- u8 bus;
- u8 dev;
- u8 fun;
- u16 dev_id;
- u16 vendor_id;
- u32 acpi_interrupt;
- u64 mmio_tra;
- u64 ioport_tra;
- u8 flags;
- u8 trans;
-} __attribute__((packed));
-
-struct pcdp_vga {
- u8 count; /* address space descriptors */
-} __attribute__((packed));
-
-/* pcdp_device.flags */
-#define PCDP_PRIMARY_CONSOLE 1
-
-struct pcdp_device {
- u8 type;
- u8 flags;
- u16 length;
- u16 efi_index;
- /* next data is pcdp_if_pci or pcdp_if_acpi (not yet supported) */
- /* next data is device specific type (currently only pcdp_vga) */
-} __attribute__((packed));
-
-struct pcdp {
- u8 signature[4];
- u32 length;
- u8 rev; /* PCDP v2.0 is rev 3 */
- u8 chksum;
- u8 oemid[6];
- u8 oem_tabid[8];
- u32 oem_rev;
- u8 creator_id[4];
- u32 creator_rev;
- u32 num_uarts;
- struct pcdp_uart uart[0]; /* actual size is num_uarts */
- /* remainder of table is pcdp_device structures */
-} __attribute__((packed));
Index: vga/include/linux/pcdp.h
=================================--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ vga/include/linux/pcdp.h 2005-10-12 10:43:38.172792280 -0500
@@ -0,0 +1,111 @@
+/*
+ * Definitions for PCDP-defined console devices
+ *
+ * v1.0a: http://www.dig64.org/specifications/DIG64_HCDPv10a_01.pdf
+ * v2.0: http://www.dig64.org/specifications/DIG64_PCDPv20.pdf
+ *
+ * (c) Copyright 2002, 2004 Hewlett-Packard Development Company, L.P.
+ * Khalid Aziz <khalid.aziz@hp.com>
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define PCDP_CONSOLE 0
+#define PCDP_DEBUG 1
+#define PCDP_CONSOLE_OUTPUT 2
+#define PCDP_CONSOLE_INPUT 3
+
+#define PCDP_UART (0 << 3)
+#define PCDP_VGA (1 << 3)
+#define PCDP_USB (2 << 3)
+
+/* pcdp_uart.type and pcdp_device.type */
+#define PCDP_CONSOLE_UART (PCDP_UART | PCDP_CONSOLE)
+#define PCDP_DEBUG_UART (PCDP_UART | PCDP_DEBUG)
+#define PCDP_CONSOLE_VGA (PCDP_VGA | PCDP_CONSOLE_OUTPUT)
+#define PCDP_CONSOLE_USB (PCDP_USB | PCDP_CONSOLE_INPUT)
+
+/* pcdp_uart.flags */
+#define PCDP_UART_EDGE_SENSITIVE (1 << 0)
+#define PCDP_UART_ACTIVE_LOW (1 << 1)
+#define PCDP_UART_PRIMARY_CONSOLE (1 << 2)
+#define PCDP_UART_IRQ (1 << 6) /* in pci_func for rev < 3 */
+#define PCDP_UART_PCI (1 << 7) /* in pci_func for rev < 3 */
+
+struct pcdp_uart {
+ u8 type;
+ u8 bits;
+ u8 parity;
+ u8 stop_bits;
+ u8 pci_seg;
+ u8 pci_bus;
+ u8 pci_dev;
+ u8 pci_func;
+ u64 baud;
+ struct acpi_generic_address addr;
+ u16 pci_dev_id;
+ u16 pci_vendor_id;
+ u32 gsi;
+ u32 clock_rate;
+ u8 pci_prog_intfc;
+ u8 flags;
+ u16 conout_index;
+ u32 reserved;
+} __attribute__((packed));
+
+#define PCDP_IF_PCI 1
+
+/* pcdp_if_pci.trans */
+#define PCDP_PCI_TRANS_IOPORT 0x02
+#define PCDP_PCI_TRANS_MMIO 0x01
+
+struct pcdp_if_pci {
+ u8 interconnect;
+ u8 reserved;
+ u16 length;
+ u8 segment;
+ u8 bus;
+ u8 dev;
+ u8 fun;
+ u16 dev_id;
+ u16 vendor_id;
+ u32 acpi_interrupt;
+ u64 mmio_tra;
+ u64 ioport_tra;
+ u8 flags;
+ u8 trans;
+} __attribute__((packed));
+
+struct pcdp_vga {
+ u8 count; /* address space descriptors */
+} __attribute__((packed));
+
+/* pcdp_device.flags */
+#define PCDP_PRIMARY_CONSOLE 1
+
+struct pcdp_device {
+ u8 type;
+ u8 flags;
+ u16 length;
+ u16 efi_index;
+ /* next data is pcdp_if_pci or pcdp_if_acpi (not yet supported) */
+ /* next data is device specific type (currently only pcdp_vga) */
+} __attribute__((packed));
+
+struct pcdp {
+ u8 signature[4];
+ u32 length;
+ u8 rev; /* PCDP v2.0 is rev 3 */
+ u8 chksum;
+ u8 oemid[6];
+ u8 oem_tabid[8];
+ u32 oem_rev;
+ u8 creator_id[4];
+ u32 creator_rev;
+ u32 num_uarts;
+ struct pcdp_uart uart[0]; /* actual size is num_uarts */
+ /* remainder of table is pcdp_device structures */
+} __attribute__((packed));