GART registers are not present in newer processors (Fam15h, Model 10h and later). So, avoid accesses to GART registers in PCI config space by returning early in early_gart_iommu_check() and gart_iommu_hole_init() if GART is not available.
Refactoring the family check used in amd_nb into an inline function so we can use it here as well as in amd_nb.c Tested the patch on Fam10h and Fam15h Model 00h-fh and this code runs fine. On Fam15h Model 60h-6fh and on Fam16h, we bail early as they don't have GART. Signed-off-by: Aravind Gopalakrishnan <[email protected]> Reviewed-by: Suravee Suthikulpanit <[email protected]> --- arch/x86/include/asm/amd_nb.h | 11 +++++++++++ arch/x86/kernel/amd_nb.c | 4 +--- arch/x86/kernel/aperture_64.c | 4 ++-- 3 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/amd_nb.h b/arch/x86/include/asm/amd_nb.h index aaac3b2..864c8bd 100644 --- a/arch/x86/include/asm/amd_nb.h +++ b/arch/x86/include/asm/amd_nb.h @@ -98,11 +98,22 @@ static inline u16 amd_get_node_id(struct pci_dev *pdev) return 0; } +static inline bool amd_gart_present(void) +{ + /* GART present only on Fam15h upto model 0fh */ + if (boot_cpu_data.x86 == 0xf || boot_cpu_data.x86 == 0x10 || + (boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model < 0x10)) + return true; + + return false; +} + #else #define amd_nb_num(x) 0 #define amd_nb_has_feature(x) false #define node_to_amd_nb(x) NULL +#define amd_gart_present(x) false #endif diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c index 5caed1d..29fa475 100644 --- a/arch/x86/kernel/amd_nb.c +++ b/arch/x86/kernel/amd_nb.c @@ -89,9 +89,7 @@ int amd_cache_northbridges(void) next_northbridge(link, amd_nb_link_ids); } - /* GART present only on Fam15h upto model 0fh */ - if (boot_cpu_data.x86 == 0xf || boot_cpu_data.x86 == 0x10 || - (boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model < 0x10)) + if (amd_gart_present()) amd_northbridges.flags |= AMD_NB_GART; /* diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c index 76164e1..1cb170b 100644 --- a/arch/x86/kernel/aperture_64.c +++ b/arch/x86/kernel/aperture_64.c @@ -262,7 +262,7 @@ void __init early_gart_iommu_check(void) u64 aper_base = 0, last_aper_base = 0; int aper_enabled = 0, last_aper_enabled = 0, last_valid = 0; - if (!early_pci_allowed()) + if (!early_pci_allowed() || !amd_gart_present()) return; /* This is mostly duplicate of iommu_hole_init */ @@ -356,7 +356,7 @@ int __init gart_iommu_hole_init(void) int i, node; if (gart_iommu_aperture_disabled || !fix_aperture || - !early_pci_allowed()) + !early_pci_allowed() || !amd_gart_present()) return -ENODEV; pr_info("Checking aperture...\n"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
