7 files changed, 60 insertions, 8 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 516225a864f9..3e69c1c4f508 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1948,8 +1948,12 @@ and is between 256 and 4096 characters. It is defined in the file
                                 IRQ routing is enabled.
                 noacpi          [X86] Do not use ACPI for IRQ routing
                                 or for PCI scanning.
-                use_crs         [X86] Use _CRS for PCI resource
-                                allocation.
+                use_crs         [X86] Use PCI host bridge window information
+                                from ACPI.  On BIOSes from 2008 or later, this
+                                is enabled by default.  If you need to use this,
+                                please report a bug.
+                nocrs           [X86] Ignore PCI host bridge windows from ACPI.
+                                If you need to use this, please report a bug.
                 routeirq        Do IRQ routing for all PCI devices.
                                 This is normally done in pci_enable_device(),
                                 so this option is a temporary workaround
diff --git a/arch/ia64/include/asm/acpi.h b/arch/ia64/include/asm/acpi.h
index e97b255d97bc..93997bd5edc3 100644
--- a/arch/ia64/include/asm/acpi.h
+++ b/arch/ia64/include/asm/acpi.h
@@ -98,6 +98,7 @@ ia64_acpi_release_global_lock (unsigned int *lock)
 #endif
 #define acpi_processor_cstate_check(x) (x) /* no idle limits on IA64 :) */
 static inline void disable_acpi(void) { }
+static inline void pci_acpi_crs_quirks(void) { }
 
 const char *acpi_get_sysname (void);
 int acpi_request_vector (u32 int_type);
diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index b4bf9a942ed0..05b58ccb2e82 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -29,6 +29,7 @@
 #define PCI_CHECK_ENABLE_AMD_MMCONF     0x20000
 #define PCI_HAS_IO_ECS          0x40000
 #define PCI_NOASSIGN_ROMS       0x80000
+#define PCI_ROOT_NO_CRS         0x100000
 
 extern unsigned int pci_probe;
 extern unsigned long pirq_table_addr;
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index a2f8cdb8c1d5..5f11ff6f5389 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -15,6 +15,51 @@ struct pci_root_info {
         int busnum;
 };
 
+static bool pci_use_crs = true;
+
+static int __init set_use_crs(const struct dmi_system_id *id)
+{
+        pci_use_crs = true;
+        return 0;
+}
+
+static const struct dmi_system_id pci_use_crs_table[] __initconst = {
+        /* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
+        {
+                .callback = set_use_crs,
+                .ident = "IBM System x3800",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
+                },
+        },
+        {}
+};
+
+void __init pci_acpi_crs_quirks(void)
+{
+        int year;
+
+        if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
+                pci_use_crs = false;
+
+        dmi_check_system(pci_use_crs_table);
+
+        /*
+         * If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
+         * takes precedence over anything we figured out above.
+         */
+        if (pci_probe & PCI_ROOT_NO_CRS)
+                pci_use_crs = false;
+        else if (pci_probe & PCI_USE__CRS)
+                pci_use_crs = true;
+
+        printk(KERN_INFO "PCI: %s host bridge windows from ACPI; "
+               "if necessary, use \"pci=%s\" and report a bug\n",
+               pci_use_crs ? "Using" : "Ignoring",
+               pci_use_crs ? "nocrs" : "use_crs");
+}
+
 static acpi_status
 resource_to_addr(struct acpi_resource *resource,
                         struct acpi_resource_address64 *addr)
@@ -106,7 +151,7 @@ setup_resource(struct acpi_resource *acpi_res, void *data)
         res->child = NULL;
         align_resource(info->bridge, res);
 
-        if (!(pci_probe & PCI_USE__CRS)) {
+        if (!pci_use_crs) {
                 dev_printk(KERN_DEBUG, &info->bridge->dev,
                            "host bridge window %pR (ignored)\n", res);
                 return AE_OK;
@@ -137,12 +182,8 @@ get_current_resources(struct acpi_device *device, int busnum,
         struct pci_root_info info;
         size_t size;
 
-        if (pci_probe & PCI_USE__CRS)
+        if (pci_use_crs)
                 pci_bus_remove_resources(bus);
-        else
-                dev_info(&device->dev,
-                         "ignoring host bridge windows from ACPI; "
-                         "boot with \"pci=use_crs\" to use them\n");
 
         info.bridge = device;
         info.bus = bus;
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index d2552c68e94d..3736176acaab 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -520,6 +520,9 @@ char * __devinit  pcibios_setup(char *str)
         } else if (!strcmp(str, "use_crs")) {
                 pci_probe |= PCI_USE__CRS;
                 return NULL;
+        } else if (!strcmp(str, "nocrs")) {
+                pci_probe |= PCI_ROOT_NO_CRS;
+                return NULL;
         } else if (!strcmp(str, "earlydump")) {
                 pci_early_dump_regs = 1;
                 return NULL;
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 9cd8bedb1e5a..d724736d56c8 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -566,6 +566,7 @@ static int __init acpi_pci_root_init(void)
         if (acpi_pci_disabled)
                 return 0;
 
+        pci_acpi_crs_quirks();
         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
                 return -ENODEV;
 
diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h
index f4906f6568d4..3a4767c01c5f 100644
--- a/include/acpi/acpi_drivers.h
+++ b/include/acpi/acpi_drivers.h
@@ -104,6 +104,7 @@ int acpi_pci_bind_root(struct acpi_device *device);
 
 struct pci_bus *pci_acpi_scan_root(struct acpi_device *device, int domain,
                                    int bus);
+void pci_acpi_crs_quirks(void);
 
 /* --------------------------------------------------------------------------
                                     Processor