EDAC, amd64: Extend ecc_enabled() to Fam17h

Update the ecc_enabled() function to work on Fam17h. This entails
reading a different set of registers and using the SMN (System
Management Network) rather than PCI devices.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/1479423463-8536-9-git-send-email-Yazen.Ghannam@amd.com
[ Fixup ecc_en assignment and get_umc_base(). ]
Signed-off-by: Borislav Petkov <bp@suse.de>

drivers/edac/amd64_edac.c

@@ -2664,20 +2664,50 @@ static const char *ecc_msg =
 
 static bool ecc_enabled(struct pci_dev *F3, u16 nid)
 {
-	u32 value;
-	u8 ecc_en = 0;
 	bool nb_mce_en = false;
+	u8 ecc_en = 0, i;
+	u32 value;
 
-	amd64_read_pci_cfg(F3, NBCFG, &value);
+	if (boot_cpu_data.x86 >= 0x17) {
+		u8 umc_en_mask = 0, ecc_en_mask = 0;
 
-	ecc_en = !!(value & NBCFG_ECC_ENABLE);
-	amd64_info("DRAM ECC %s.\n", (ecc_en ? "enabled" : "disabled"));
+		for (i = 0; i < NUM_UMCS; i++) {
+			u32 base = get_umc_base(i);
+
+			/* Only check enabled UMCs. */
+			if (amd_smn_read(nid, base + UMCCH_SDP_CTRL, &value))
+				continue;
+
+			if (!(value & UMC_SDP_INIT))
+				continue;
+
+			umc_en_mask |= BIT(i);
+
+			if (amd_smn_read(nid, base + UMCCH_UMC_CAP_HI, &value))
+				continue;
+
+			if (value & UMC_ECC_ENABLED)
+				ecc_en_mask |= BIT(i);
+		}
+
+		/* Check whether at least one UMC is enabled: */
+		if (umc_en_mask)
+			ecc_en = umc_en_mask == ecc_en_mask;
+
+		/* Assume UMC MCA banks are enabled. */
+		nb_mce_en = true;
+	} else {
+		amd64_read_pci_cfg(F3, NBCFG, &value);
 
-	nb_mce_en = nb_mce_bank_enabled_on_node(nid);
-	if (!nb_mce_en)
-		amd64_notice("NB MCE bank disabled, set MSR "
-			     "0x%08x[4] on node %d to enable.\n",
-			     MSR_IA32_MCG_CTL, nid);
+		ecc_en = !!(value & NBCFG_ECC_ENABLE);
+
+		nb_mce_en = nb_mce_bank_enabled_on_node(nid);
+		if (!nb_mce_en)
+			amd64_notice("NB MCE bank disabled, set MSR 0x%08x[4] on node %d to enable.\n",
+				     MSR_IA32_MCG_CTL, nid);
+	}
+
+	amd64_info("DRAM ECC %s.\n", (ecc_en ? "enabled" : "disabled"));
 
 	if (!ecc_en || !nb_mce_en) {
 		amd64_notice("%s", ecc_msg);

drivers/edac/amd64_edac.h

@@ -248,6 +248,16 @@
 /* MSRs */
 #define MSR_MCGCTL_NBE			BIT(4)
 
+/* UMC CH register offsets */
+#define UMCCH_SDP_CTRL			0x104
+#define UMCCH_UMC_CAP_HI		0xDF4
+
+/* UMC CH bitfields */
+#define UMC_ECC_ENABLED			BIT(30)
+#define UMC_SDP_INIT			BIT(31)
+
+#define NUM_UMCS			2
+
 enum amd_families {
 	K8_CPUS = 0,
 	F10_CPUS,
@@ -354,6 +364,12 @@ struct err_info {
 	u32 offset;
 };
 
+static inline u32 get_umc_base(u8 channel)
+{
+	/* ch0: 0x50000, ch1: 0x150000 */
+	return 0x50000 + (!!channel << 20);
+}
+
 static inline u64 get_dram_base(struct amd64_pvt *pvt, u8 i)
 {
 	u64 addr = ((u64)pvt->ranges[i].base.lo & 0xffff0000) << 8;