EDAC, MCE: Add F15h CU MCE decoder

MCE bank 2 is redefined from a BU to a CU (Combined Unit) bank on F15h.
Add a decoder function for CU MCEs.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

drivers/edac/mce_amd.c

@@ -95,6 +95,23 @@ static const char * const f15h_ic_mce_desc[] = {
 	"fetch address FIFO"
 };
 
+static const char * const f15h_cu_mce_desc[] = {
+	"Fill ECC error on data fills",			/* xec = 0x4 */
+	"Fill parity error on insn fills",
+	"Prefetcher request FIFO parity error",
+	"PRQ address parity error",
+	"PRQ data parity error",
+	"WCC Tag ECC error",
+	"WCC Data ECC error",
+	"WCB Data parity error",
+	"VB Data/ECC error",
+	"L2 Tag ECC error",				/* xec = 0x10 */
+	"Hard L2 Tag ECC error",
+	"Multiple hits on L2 tag",
+	"XAB parity error",
+	"PRB address parity error"
+};
+
 static bool f12h_dc_mce(u16 ec, u8 xec)
 {
 	bool ret = false;
@@ -405,6 +422,46 @@ static void amd_decode_bu_mce(struct mce *m)
 	pr_emerg(HW_ERR "Corrupted BU MCE info?\n");
 }
 
+static void amd_decode_cu_mce(struct mce *m)
+{
+	u16 ec = m->status & 0xffff;
+	u8 xec = (m->status >> 16) & xec_mask;
+
+	pr_emerg(HW_ERR "Combined Unit Error: ");
+
+	if (TLB_ERROR(ec)) {
+		if (xec == 0x0)
+			pr_cont("Data parity TLB read error.\n");
+		else if (xec == 0x1)
+			pr_cont("Poison data provided for TLB fill.\n");
+		else
+			goto wrong_cu_mce;
+	} else if (BUS_ERROR(ec)) {
+		if (xec > 2)
+			goto wrong_cu_mce;
+
+		pr_cont("Error during attempted NB data read.\n");
+	} else if (MEM_ERROR(ec)) {
+		switch (xec) {
+		case 0x4 ... 0xc:
+			pr_cont("%s.\n", f15h_cu_mce_desc[xec - 0x4]);
+			break;
+
+		case 0x10 ... 0x14:
+			pr_cont("%s.\n", f15h_cu_mce_desc[xec - 0x7]);
+			break;
+
+		default:
+			goto wrong_cu_mce;
+		}
+	}
+
+	return;
+
+wrong_cu_mce:
+	pr_emerg(HW_ERR "Corrupted CU MCE info?\n");
+}
+
 static void amd_decode_ls_mce(struct mce *m)
 {
 	u16 ec = m->status & 0xffff;
@@ -665,7 +722,10 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 		break;
 
 	case 2:
-		amd_decode_bu_mce(m);
+		if (boot_cpu_data.x86 == 0x15)
+			amd_decode_cu_mce(m);
+		else
+			amd_decode_bu_mce(m);
 		break;
 
 	case 3: