x86/mce: Add Zhaoxin LMCE support

Newer Zhaoxin CPUs support LMCE compatible with Intel. Add support for
that.

 [ bp: Export functions and massage. ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: CooperYan@zhaoxin.com
Cc: DavidWang@zhaoxin.com
Cc: HerryYang@zhaoxin.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: QiyuanWang@zhaoxin.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1568787573-1297-5-git-send-email-TonyWWang-oc@zhaoxin.com

arch/x86/kernel/cpu/mce/core.c

@@ -1132,6 +1132,12 @@ 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;
+		}
+
 		if (mcgstatus & MCG_STATUS_RIPV) {
 			mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
 			return true;
@@ -1282,9 +1288,10 @@ 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;
 
 	/*
@@ -1797,9 +1804,15 @@ static void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c)
 	}
 
 	intel_init_cmci();
+	intel_init_lmce();
 	mce_adjust_timer = cmci_intel_adjust_timer;
 }
 
+static void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c)
+{
+	intel_clear_lmce();
+}
+
 static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
 {
 	switch (c->x86_vendor) {
@@ -1836,6 +1849,11 @@ 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;
 	}

arch/x86/kernel/cpu/mce/intel.c

@@ -444,7 +444,7 @@ void intel_init_cmci(void)
 	cmci_recheck();
 }
 
-static void intel_init_lmce(void)
+void intel_init_lmce(void)
 {
 	u64 val;
 
@@ -457,7 +457,7 @@ static void intel_init_lmce(void)
 		wrmsrl(MSR_IA32_MCG_EXT_CTL, val | MCG_EXT_CTL_LMCE_EN);
 }
 
-static void intel_clear_lmce(void)
+void intel_clear_lmce(void)
 {
 	u64 val;
 

arch/x86/kernel/cpu/mce/internal.h

@@ -46,12 +46,16 @@ bool mce_intel_cmci_poll(void);
 void mce_intel_hcpu_update(unsigned long cpu);
 void cmci_disable_bank(int bank);
 void intel_init_cmci(void);
+void intel_init_lmce(void);
+void intel_clear_lmce(void);
 #else
 # define cmci_intel_adjust_timer mce_adjust_timer_default
 static inline bool mce_intel_cmci_poll(void) { return false; }
 static inline void mce_intel_hcpu_update(unsigned long cpu) { }
 static inline void cmci_disable_bank(int bank) { }
 static inline void intel_init_cmci(void) { }
+static inline void intel_init_lmce(void) { }
+static inline void intel_clear_lmce(void) { }
 #endif
 
 void mce_timer_kick(unsigned long interval);