diff options
Diffstat (limited to 'arch/x86_64/kernel/early-quirks_64.c')
-rw-r--r-- | arch/x86_64/kernel/early-quirks_64.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/early-quirks_64.c b/arch/x86_64/kernel/early-quirks_64.c new file mode 100644 index 00000000000..13aa4fd728f --- /dev/null +++ b/arch/x86_64/kernel/early-quirks_64.c @@ -0,0 +1,127 @@ +/* Various workarounds for chipset bugs. + This code runs very early and can't use the regular PCI subsystem + The entries are keyed to PCI bridges which usually identify chipsets + uniquely. + This is only for whole classes of chipsets with specific problems which + need early invasive action (e.g. before the timers are initialized). + Most PCI device specific workarounds can be done later and should be + in standard PCI quirks + Mainboard specific bugs should be handled by DMI entries. + CPU specific bugs in setup.c */ + +#include <linux/pci.h> +#include <linux/acpi.h> +#include <linux/pci_ids.h> +#include <asm/pci-direct.h> +#include <asm/proto.h> +#include <asm/iommu.h> +#include <asm/dma.h> + +static void __init via_bugs(void) +{ +#ifdef CONFIG_IOMMU + if ((end_pfn > MAX_DMA32_PFN || force_iommu) && + !iommu_aperture_allowed) { + printk(KERN_INFO + "Looks like a VIA chipset. Disabling IOMMU. Override with iommu=allowed\n"); + iommu_aperture_disabled = 1; + } +#endif +} + +#ifdef CONFIG_ACPI + +static int __init nvidia_hpet_check(struct acpi_table_header *header) +{ + return 0; +} +#endif + +static void __init nvidia_bugs(void) +{ +#ifdef CONFIG_ACPI + /* + * All timer overrides on Nvidia are + * wrong unless HPET is enabled. + * Unfortunately that's not true on many Asus boards. + * We don't know yet how to detect this automatically, but + * at least allow a command line override. + */ + if (acpi_use_timer_override) + return; + + if (acpi_table_parse(ACPI_SIG_HPET, nvidia_hpet_check)) { + acpi_skip_timer_override = 1; + printk(KERN_INFO "Nvidia board " + "detected. Ignoring ACPI " + "timer override.\n"); + printk(KERN_INFO "If you got timer trouble " + "try acpi_use_timer_override\n"); + } +#endif + /* RED-PEN skip them on mptables too? */ + +} + +static void __init ati_bugs(void) +{ + if (timer_over_8254 == 1) { + timer_over_8254 = 0; + printk(KERN_INFO + "ATI board detected. Disabling timer routing over 8254.\n"); + } +} + +struct chipset { + u16 vendor; + void (*f)(void); +}; + +static struct chipset early_qrk[] __initdata = { + { PCI_VENDOR_ID_NVIDIA, nvidia_bugs }, + { PCI_VENDOR_ID_VIA, via_bugs }, + { PCI_VENDOR_ID_ATI, ati_bugs }, + {} +}; + +void __init early_quirks(void) +{ + int num, slot, func; + + if (!early_pci_allowed()) + return; + + /* Poor man's PCI discovery */ + for (num = 0; num < 32; num++) { + for (slot = 0; slot < 32; slot++) { + for (func = 0; func < 8; func++) { + u32 class; + u32 vendor; + u8 type; + int i; + class = read_pci_config(num,slot,func, + PCI_CLASS_REVISION); + if (class == 0xffffffff) + break; + + if ((class >> 16) != PCI_CLASS_BRIDGE_PCI) + continue; + + vendor = read_pci_config(num, slot, func, + PCI_VENDOR_ID); + vendor &= 0xffff; + + for (i = 0; early_qrk[i].f; i++) + if (early_qrk[i].vendor == vendor) { + early_qrk[i].f(); + return; + } + + type = read_pci_config_byte(num, slot, func, + PCI_HEADER_TYPE); + if (!(type & 0x80)) + break; + } + } + } +} |