[PATCH 3/3] EDAC/mce_amd: Add support for FRU Text in MCA

[Yazen Ghannam]

A new "FRU Text in MCA" feature is defined where the Field Replaceable
Unit (FRU) Text for a device is represented by a string in the new
MCA_SYND1 and MCA_SYND2 registers. This feature is supported per MCA
bank, and it is advertised by the McaFruTextInMca bit (MCA_CONFIG[9]).

The FRU Text is populated dynamically for each individual error state
(MCA_STATUS, MCA_ADDR, et al.). This handles the case where an MCA bank
covers multiple devices, for example, a Unified Memory Controller (UMC)
bank that manages two DIMMs.

Print the FRU Text string, if available, when decoding an MCA error.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
 drivers/edac/mce_amd.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
index 28b48c711fe0..3cacc3f22379 100644
--- a/drivers/edac/mce_amd.c
+++ b/drivers/edac/mce_amd.c
@@ -1235,6 +1235,7 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 {
 	struct mce *m = (struct mce *)data;
 	unsigned int fam = x86_family(m->cpuid);
+	u64 mca_config = 0;
 	int ecc;
 
 	if (m->kflags & MCE_HANDLED_CEC)
@@ -1254,11 +1255,10 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 		((m->status & MCI_STATUS_PCC)	? "PCC"	  : "-"));
 
 	if (boot_cpu_has(X86_FEATURE_SMCA)) {
-		u32 low, high;
 		u32 addr = MSR_AMD64_SMCA_MCx_CONFIG(m->bank);
 
-		if (!rdmsr_safe(addr, &low, &high) &&
-		    (low & MCI_CONFIG_MCAX))
+		if (!rdmsrl_safe_on_cpu(m->extcpu, addr, &mca_config) &&
+		    (mca_config & MCI_CONFIG_MCAX))
 			pr_cont("|%s", ((m->status & MCI_STATUS_TCC) ? "TCC" : "-"));
 
 		pr_cont("|%s", ((m->status & MCI_STATUS_SYNDV) ? "SyndV" : "-"));
@@ -1300,6 +1300,17 @@ amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 		pr_cont("\n");
 
 		decode_smca_error(m);
+
+		if (mca_config & BIT(9)) {
+			char frutext[32];
+
+			memset(frutext, 0, sizeof(frutext));
+			memcpy(&frutext[0], &m->synd1, 8);
+			memcpy(&frutext[8], &m->synd2, 8);
+
+			pr_emerg(HW_ERR "FRU Text: %s\n", frutext);
+		}
+
 		goto err_code;
 	}
 
-- 
2.25.1