The Hygon Dhyana CPU has a special magic MSR way to force WB for memory >4GB, and support TOP_MEM2. Therefore, it is necessary to add Hygon Dhyana support in amd_special_default_mtrr(). The number of variable MTRRs for Hygon is 2 as AMD's. Signed-off-by: Pu Wen <puwen@xxxxxxxx> Reviewed-by: Borislav Petkov <bp@xxxxxxx> --- arch/x86/kernel/cpu/mtrr/cleanup.c | 3 ++- arch/x86/kernel/cpu/mtrr/mtrr.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c index 765afd5..3668c5d 100644 --- a/arch/x86/kernel/cpu/mtrr/cleanup.c +++ b/arch/x86/kernel/cpu/mtrr/cleanup.c @@ -831,7 +831,8 @@ int __init amd_special_default_mtrr(void) { u32 l, h; - if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) + if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD && + boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) return 0; if (boot_cpu_data.x86 < 0xf) return 0; diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c index 9a19c80..507039c 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.c +++ b/arch/x86/kernel/cpu/mtrr/mtrr.c @@ -127,7 +127,7 @@ static void __init set_num_var_ranges(void) if (use_intel()) rdmsr(MSR_MTRRcap, config, dummy); - else if (is_cpu(AMD)) + else if (is_cpu(AMD) || is_cpu(HYGON)) config = 2; else if (is_cpu(CYRIX) || is_cpu(CENTAUR)) config = 8; -- 2.7.4