x86/mce: Add Zhaoxin MCE support

All newer Zhaoxin CPUs are compatible with Intel's Machine-Check
Architecture, so add support for them.

 [ bp: Reflow comment in vendor_disable_error_reporting() and massage
   commit message. ]

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/1568787573-1297-2-git-send-email-TonyWWang-oc@zhaoxin.com

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

@@ -488,8 +488,9 @@ int mce_usable_address(struct mce *m)
 	if (!(m->status & MCI_STATUS_ADDRV))
 		return 0;
 
-	/* Checks after this one are Intel-specific: */
+	/* Checks after this one are Intel/Zhaoxin-specific: */
-	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
+	    boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
 		return 1;
 
 	if (!(m->status & MCI_STATUS_MISCV))
@@ -507,10 +508,13 @@ EXPORT_SYMBOL_GPL(mce_usable_address);
 
 bool mce_is_memory_error(struct mce *m)
 {
-	if (m->cpuvendor == X86_VENDOR_AMD ||
+	switch (m->cpuvendor) {
-	    m->cpuvendor == X86_VENDOR_HYGON) {
+	case X86_VENDOR_AMD:
+	case X86_VENDOR_HYGON:
 		return amd_mce_is_memory_error(m);
-	} else if (m->cpuvendor == X86_VENDOR_INTEL) {
+
+	case X86_VENDOR_INTEL:
+	case X86_VENDOR_ZHAOXIN:
 		/*
 		 * Intel SDM Volume 3B - 15.9.2 Compound Error Codes
 		 *
@@ -527,9 +531,10 @@ bool mce_is_memory_error(struct mce *m)
 		return (m->status & 0xef80) == BIT(7) ||
 		       (m->status & 0xef00) == BIT(8) ||
 		       (m->status & 0xeffc) == 0xc;
-	}
 
-	return false;
+	default:
+		return false;
+	}
 }
 EXPORT_SYMBOL_GPL(mce_is_memory_error);
 
@@ -1697,6 +1702,18 @@ static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
 		if (c->x86 == 6 && c->x86_model == 45)
 			quirk_no_way_out = quirk_sandybridge_ifu;
 	}
+
+	if (c->x86_vendor == X86_VENDOR_ZHAOXIN) {
+		/*
+		 * All newer Zhaoxin CPUs support MCE broadcasting. Enable
+		 * synchronization with a one second timeout.
+		 */
+		if (c->x86 > 6 || (c->x86_model == 0x19 || c->x86_model == 0x1f)) {
+			if (cfg->monarch_timeout < 0)
+				cfg->monarch_timeout = USEC_PER_SEC;
+		}
+	}
+
 	if (cfg->monarch_timeout < 0)
 		cfg->monarch_timeout = 0;
 	if (cfg->bootlog != 0)
@@ -2014,15 +2031,16 @@ static void mce_disable_error_reporting(void)
 static void vendor_disable_error_reporting(void)
 {
 	/*
-	 * Don't clear on Intel or AMD or Hygon CPUs. Some of these MSRs
+	 * Don't clear on Intel or AMD or Hygon or Zhaoxin CPUs. Some of these
-	 * are socket-wide.
+	 * MSRs are socket-wide. Disabling them for just a single offlined CPU
-	 * Disabling them for just a single offlined CPU is bad, since it will
+	 * is bad, since it will inhibit reporting for all shared resources on
-	 * inhibit reporting for all shared resources on the socket like the
+	 * the socket like the last level cache (LLC), the integrated memory
-	 * last level cache (LLC), the integrated memory controller (iMC), etc.
+	 * controller (iMC), etc.
 	 */
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL ||
 	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON ||
-	    boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+	    boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_ZHAOXIN)
 		return;
 
 	mce_disable_error_reporting();