[PATCH v5 03/16] x86/mtrr: get MTRR number and support TOP_MEM2
From: Pu Wen <puwen@hygon.cn>
Date: 2018-08-29 12:43:42
Also in:
lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Hygon CPU have a special magic MSR way to force WB for memory >4GB, and also support TOP_MEM2. Therefore, it is necessary to add Hygon support in amd_special_default_mtrr(). The MtrrFixDramModEn bit on Hygon platform should also be set to 1 during BIOS initialization of the fixed MTRRs, then cleared to 0 for operation. The number of variable MTRRs for Hygon is 2 as AMD's. Signed-off-by: Pu Wen <puwen@hygon.cn> --- arch/x86/kernel/cpu/mtrr/cleanup.c | 3 ++- arch/x86/kernel/cpu/mtrr/generic.c | 5 +++-- arch/x86/kernel/cpu/mtrr/mtrr.c | 2 +- 3 files changed, 6 insertions(+), 4 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/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index e12ee86..77c3eaa 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c@@ -49,8 +49,9 @@ static inline void k8_check_syscfg_dram_mod_en(void) { u32 lo, hi; - if (!((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && - (boot_cpu_data.x86 >= 0x0f))) + if (!((boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + boot_cpu_data.x86 >= 0x0f) || + boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)) return; rdmsr(MSR_K8_SYSCFG, lo, hi);
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