diff mbox

x86/PCI: Ignore _SEG on HP xw9300

Message ID 20121105223306.7246.36325.stgit@bhelgaas.mtv.corp.google.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Bjorn Helgaas Nov. 5, 2012, 10:33 p.m. UTC
The xw9300 BIOS supplies _SEG methods that are incorrect, which results
in some LSI SCSI devices not being discovered.  This adds a quirk to
ignore _SEG on this machine and default to zero.

The xw9300 has three host bridges:

    ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-3f])
    ACPI: PCI Root Bridge [PCI1] (domain 0001 [bus 40-7f])
    ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 80-ff])

When the BIOS "ACPI Bus Segmentation" option is enabled (as it is by
default), the _SEG methods of the PCI1 and PCI2 bridges return 1 and 2,
respectively.  However, the BIOS implementation appears to be incomplete,
and we can't enumerate devices in those domains.

But if we assume PCI1 and PCI2 really lead to buses in domain 0,
everything works fine.  Windows XP and Vista also seem to ignore
these _SEG methods.

Reference: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=543308
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=15362
Reported-and-Tested-by: Sean M. Pappalardo <pegasus@renegadetech.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/x86/pci/acpi.c |   25 +++++++++++++++++++++++--
 1 files changed, 23 insertions(+), 2 deletions(-)


--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

Bjorn Helgaas Nov. 5, 2012, 10:34 p.m. UTC | #1
On Mon, Nov 5, 2012 at 3:33 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> The xw9300 BIOS supplies _SEG methods that are incorrect, which results
> in some LSI SCSI devices not being discovered.  This adds a quirk to
> ignore _SEG on this machine and default to zero.
>
> The xw9300 has three host bridges:
>
>     ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-3f])
>     ACPI: PCI Root Bridge [PCI1] (domain 0001 [bus 40-7f])
>     ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 80-ff])
>
> When the BIOS "ACPI Bus Segmentation" option is enabled (as it is by
> default), the _SEG methods of the PCI1 and PCI2 bridges return 1 and 2,
> respectively.  However, the BIOS implementation appears to be incomplete,
> and we can't enumerate devices in those domains.
>
> But if we assume PCI1 and PCI2 really lead to buses in domain 0,
> everything works fine.  Windows XP and Vista also seem to ignore
> these _SEG methods.
>
> Reference: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=543308
> Reference: https://bugzilla.kernel.org/show_bug.cgi?id=15362
> Reported-and-Tested-by: Sean M. Pappalardo <pegasus@renegadetech.com>
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Sorry, I forgot to post this here.  Speak up if you see any issues.

I applied this to my pci/misc branch as v3.8 material.

> ---
>  arch/x86/pci/acpi.c |   25 +++++++++++++++++++++++--
>  1 files changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
> index 192397c..49e5195 100644
> --- a/arch/x86/pci/acpi.c
> +++ b/arch/x86/pci/acpi.c
> @@ -22,6 +22,7 @@ struct pci_root_info {
>  };
>
>  static bool pci_use_crs = true;
> +static bool pci_ignore_seg = false;
>
>  static int __init set_use_crs(const struct dmi_system_id *id)
>  {
> @@ -35,7 +36,14 @@ static int __init set_nouse_crs(const struct dmi_system_id *id)
>         return 0;
>  }
>
> -static const struct dmi_system_id pci_use_crs_table[] __initconst = {
> +static int __init set_ignore_seg(const struct dmi_system_id *id)
> +{
> +       printk(KERN_INFO "PCI: %s detected: ignoring ACPI _SEG\n", id->ident);
> +       pci_ignore_seg = true;
> +       return 0;
> +}
> +
> +static const struct dmi_system_id pci_crs_quirks[] __initconst = {
>         /* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
>         {
>                 .callback = set_use_crs,
> @@ -98,6 +106,16 @@ static const struct dmi_system_id pci_use_crs_table[] __initconst = {
>                         DMI_MATCH(DMI_BIOS_VERSION, "6JET85WW (1.43 )"),
>                 },
>         },
> +
> +       /* https://bugzilla.kernel.org/show_bug.cgi?id=15362 */
> +       {
> +               .callback = set_ignore_seg,
> +               .ident = "HP xw9300",
> +               .matches = {
> +                       DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
> +                       DMI_MATCH(DMI_PRODUCT_NAME, "HP xw9300 Workstation"),
> +               },
> +       },
>         {}
>  };
>
> @@ -108,7 +126,7 @@ void __init pci_acpi_crs_quirks(void)
>         if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
>                 pci_use_crs = false;
>
> -       dmi_check_system(pci_use_crs_table);
> +       dmi_check_system(pci_crs_quirks);
>
>         /*
>          * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
> @@ -455,6 +473,9 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
>         int pxm;
>  #endif
>
> +       if (pci_ignore_seg)
> +               domain = 0;
> +
>         if (domain && !pci_domains_supported) {
>                 printk(KERN_WARNING "pci_bus %04x:%02x: "
>                        "ignored (multiple domains not supported)\n",
>
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 192397c..49e5195 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -22,6 +22,7 @@  struct pci_root_info {
 };
 
 static bool pci_use_crs = true;
+static bool pci_ignore_seg = false;
 
 static int __init set_use_crs(const struct dmi_system_id *id)
 {
@@ -35,7 +36,14 @@  static int __init set_nouse_crs(const struct dmi_system_id *id)
 	return 0;
 }
 
-static const struct dmi_system_id pci_use_crs_table[] __initconst = {
+static int __init set_ignore_seg(const struct dmi_system_id *id)
+{
+	printk(KERN_INFO "PCI: %s detected: ignoring ACPI _SEG\n", id->ident);
+	pci_ignore_seg = true;
+	return 0;
+}
+
+static const struct dmi_system_id pci_crs_quirks[] __initconst = {
 	/* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
 	{
 		.callback = set_use_crs,
@@ -98,6 +106,16 @@  static const struct dmi_system_id pci_use_crs_table[] __initconst = {
 			DMI_MATCH(DMI_BIOS_VERSION, "6JET85WW (1.43 )"),
 		},
 	},
+
+	/* https://bugzilla.kernel.org/show_bug.cgi?id=15362 */
+	{
+		.callback = set_ignore_seg,
+		.ident = "HP xw9300",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "HP xw9300 Workstation"),
+		},
+	},
 	{}
 };
 
@@ -108,7 +126,7 @@  void __init pci_acpi_crs_quirks(void)
 	if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
 		pci_use_crs = false;
 
-	dmi_check_system(pci_use_crs_table);
+	dmi_check_system(pci_crs_quirks);
 
 	/*
 	 * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
@@ -455,6 +473,9 @@  struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
 	int pxm;
 #endif
 
+	if (pci_ignore_seg)
+		domain = 0;
+
 	if (domain && !pci_domains_supported) {
 		printk(KERN_WARNING "pci_bus %04x:%02x: "
 		       "ignored (multiple domains not supported)\n",