[PATCH v2 4/4] x86/mce: Add Zhaoxin LMCE support

[Tony W Wang-oc]

Zhaoxin newer CPUs support LMCE that compatible with Intel's
"Machine-Check Architecture", so add support for Zhaoxin LMCE
in mce/core.c.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@xxxxxxxxxxx>
---
v1->v2:
 - Fix redefinition of "mce_zhaoxin_feature_clear"

 arch/x86/include/asm/mce.h     |  2 ++
 arch/x86/kernel/cpu/mce/core.c | 25 +++++++++++++++++++++++--
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 0986a11..01840ec 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -352,8 +352,10 @@ static inline void mce_hygon_feature_init(struct cpuinfo_x86 *c)	{ return mce_am
 
 #ifdef CONFIG_CPU_SUP_ZHAOXIN
 void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c);
+void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c);
 #else
 static inline void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c) { }
+static inline void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c) { }
 #endif
 
 #endif /* _ASM_X86_MCE_H */
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 8a36833..595d3af7ac 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1129,6 +1129,17 @@ static bool __mc_check_crashing_cpu(int cpu)
 		u64 mcgstatus;
 
 		mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
+
+		if (boot_cpu_data.x86_vendor == X86_VENDOR_ZHAOXIN) {
+			if (mcgstatus & MCG_STATUS_LMCES) {
+				return false;
+			} else {
+				if (mcgstatus & MCG_STATUS_RIPV)
+					mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
+				return true;
+			}
+		}
+
 		if (mcgstatus & MCG_STATUS_RIPV) {
 			mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
 			return true;
@@ -1279,9 +1290,10 @@ void do_machine_check(struct pt_regs *regs, long error_code)
 
 	/*
 	 * Check if this MCE is signaled to only this logical processor,
-	 * on Intel only.
+	 * on Intel, Zhaoxin only.
 	 */
-	if (m.cpuvendor == X86_VENDOR_INTEL)
+	if (m.cpuvendor == X86_VENDOR_INTEL ||
+	    m.cpuvendor == X86_VENDOR_ZHAOXIN)
 		lmce = m.mcgstatus & MCG_STATUS_LMCES;
 
 	/*
@@ -1796,8 +1808,14 @@ void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c)
 	}
 
 	intel_init_cmci();
+	intel_init_lmce();
 	mce_adjust_timer = cmci_intel_adjust_timer;
 }
+
+void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c)
+{
+	intel_clear_lmce();
+}
 #endif
 
 static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
@@ -1836,6 +1854,9 @@ static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
 	case X86_VENDOR_INTEL:
 		mce_intel_feature_clear(c);
 		break;
+	case X86_VENDOR_ZHAOXIN:
+		mce_zhaoxin_feature_clear(c);
+		break;
 	default:
 		break;
 	}
-- 
2.7.4