diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 9 | ||||
| -rw-r--r-- | arch/x86/include/asm/pci_x86.h | 2 | ||||
| -rw-r--r-- | arch/x86/pci/acpi.c | 18 | ||||
| -rw-r--r-- | arch/x86/pci/common.c | 8 |
4 files changed, 35 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 3f1cc5e317ed..2477b639d5c4 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4066,6 +4066,15 @@ please report a bug. nocrs [X86] Ignore PCI host bridge windows from ACPI. If you need to use this, please report a bug. + use_e820 [X86] Use E820 reservations to exclude parts of + PCI host bridge windows. This is a workaround + for BIOS defects in host bridge _CRS methods. + If you need to use this, please report a bug to + <linux-pci@vger.kernel.org>. + no_e820 [X86] Ignore E820 reservations for PCI host + bridge windows. This is the default on modern + hardware. If you need to use this, please report + a bug to <linux-pci@vger.kernel.org>. 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/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h index a0627dfae541..ce3fd3311772 100644 --- a/arch/x86/include/asm/pci_x86.h +++ b/arch/x86/include/asm/pci_x86.h @@ -42,6 +42,8 @@ do { \ #define PCI_ROOT_NO_CRS 0x100000 #define PCI_NOASSIGN_BARS 0x200000 #define PCI_BIG_ROOT_WINDOW 0x400000 +#define PCI_USE_E820 0x800000 +#define PCI_NO_E820 0x1000000 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 562c81a51ea0..c61c815efedb 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -20,6 +20,7 @@ struct pci_root_info { #endif }; +static bool pci_use_e820 = true; static bool pci_use_crs = true; static bool pci_ignore_seg; @@ -161,6 +162,17 @@ void __init pci_acpi_crs_quirks(void) "if necessary, use \"pci=%s\" and report a bug\n", pci_use_crs ? "Using" : "Ignoring", pci_use_crs ? "nocrs" : "use_crs"); + + /* "pci=use_e820"/"pci=no_e820" on the kernel cmdline takes precedence */ + if (pci_probe & PCI_NO_E820) + pci_use_e820 = false; + else if (pci_probe & PCI_USE_E820) + pci_use_e820 = true; + + printk(KERN_INFO "PCI: %s E820 reservations for host bridge windows\n", + pci_use_e820 ? "Using" : "Ignoring"); + if (pci_probe & (PCI_NO_E820 | PCI_USE_E820)) + printk(KERN_INFO "PCI: Please notify linux-pci@vger.kernel.org so future kernels can this automatically\n"); } #ifdef CONFIG_PCI_MMCONFIG @@ -301,8 +313,10 @@ static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci) status = acpi_pci_probe_root_resources(ci); - resource_list_for_each_entry(entry, &ci->resources) - remove_e820_regions(&device->dev, entry->res); + if (pci_use_e820) { + resource_list_for_each_entry(entry, &ci->resources) + remove_e820_regions(&device->dev, entry->res); + } if (pci_use_crs) { resource_list_for_each_entry_safe(entry, tmp, &ci->resources) diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index 9e1e6b8d8876..ddb798603201 100644 --- a/arch/x86/pci/common.c +++ b/arch/x86/pci/common.c @@ -595,6 +595,14 @@ char *__init pcibios_setup(char *str) } else if (!strcmp(str, "nocrs")) { pci_probe |= PCI_ROOT_NO_CRS; return NULL; + } else if (!strcmp(str, "use_e820")) { + pci_probe |= PCI_USE_E820; + add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); + return NULL; + } else if (!strcmp(str, "no_e820")) { + pci_probe |= PCI_NO_E820; + add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); + return NULL; #ifdef CONFIG_PHYS_ADDR_T_64BIT } else if (!strcmp(str, "big_root_window")) { pci_probe |= PCI_BIG_ROOT_WINDOW; |