EDAC/amd64: Split ecc_enabled() into dct/umc functions

Call them using a function pointer in pvt->ops. The "ECC enabled"
check is done outside of the hardware information gathering done in
hw_info_get(). So a high-level function pointer is needed to separate
the legacy and modern paths.

No functional change is intended.

  [Yazen: rebased/reworked patch and reworded commit message. ]
Signed-off-by: Muralidhara M K <muralidhara.mk@amd.com>
Co-developed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Signed-off-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Co-developed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230127170419.1824692-17-yazen.ghannam@amd.com

drivers/edac/amd64_edac.c

@@ -3527,52 +3527,59 @@ static void restore_ecc_error_reporting(struct ecc_settings *s, u16 nid,
 		amd64_warn("Error restoring NB MCGCTL settings!\n");
 }
 
-static bool ecc_enabled(struct amd64_pvt *pvt)
+static bool dct_ecc_enabled(struct amd64_pvt *pvt)
 {
 	u16 nid = pvt->mc_node_id;
 	bool nb_mce_en = false;
-	u8 ecc_en = 0, i;
+	u8 ecc_en = 0;
 	u32 value;
 
-	if (boot_cpu_data.x86 >= 0x17) {
-		u8 umc_en_mask = 0, ecc_en_mask = 0;
-		struct amd64_umc *umc;
+	amd64_read_pci_cfg(pvt->F3, NBCFG, &value);
 
-		for_each_umc(i) {
-			umc = &pvt->umc[i];
+	ecc_en = !!(value & NBCFG_ECC_ENABLE);
 
-			/* Only check enabled UMCs. */
-			if (!(umc->sdp_ctrl & UMC_SDP_INIT))
-				continue;
+	nb_mce_en = nb_mce_bank_enabled_on_node(nid);
+	if (!nb_mce_en)
+		edac_dbg(0, "NB MCE bank disabled, set MSR 0x%08x[4] on node %d to enable.\n",
+			 MSR_IA32_MCG_CTL, nid);
 
-			umc_en_mask |= BIT(i);
+	edac_dbg(3, "Node %d: DRAM ECC %s.\n", nid, (ecc_en ? "enabled" : "disabled"));
 
-			if (umc->umc_cap_hi & UMC_ECC_ENABLED)
-				ecc_en_mask |= BIT(i);
-		}
+	if (!ecc_en || !nb_mce_en)
+		return false;
+	else
+		return true;
+}
 
-		/* Check whether at least one UMC is enabled: */
-		if (umc_en_mask)
-			ecc_en = umc_en_mask == ecc_en_mask;
-		else
-			edac_dbg(0, "Node %d: No enabled UMCs.\n", nid);
+static bool umc_ecc_enabled(struct amd64_pvt *pvt)
+{
+	u8 umc_en_mask = 0, ecc_en_mask = 0;
+	u16 nid = pvt->mc_node_id;
+	struct amd64_umc *umc;
+	u8 ecc_en = 0, i;
 
-		/* Assume UMC MCA banks are enabled. */
-		nb_mce_en = true;
-	} else {
-		amd64_read_pci_cfg(pvt->F3, NBCFG, &value);
+	for_each_umc(i) {
+		umc = &pvt->umc[i];
+
+		/* Only check enabled UMCs. */
+		if (!(umc->sdp_ctrl & UMC_SDP_INIT))
+			continue;
 
-		ecc_en = !!(value & NBCFG_ECC_ENABLE);
+		umc_en_mask |= BIT(i);
 
-		nb_mce_en = nb_mce_bank_enabled_on_node(nid);
-		if (!nb_mce_en)
-			edac_dbg(0, "NB MCE bank disabled, set MSR 0x%08x[4] on node %d to enable.\n",
-				     MSR_IA32_MCG_CTL, nid);
+		if (umc->umc_cap_hi & 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;
+	else
+		edac_dbg(0, "Node %d: No enabled UMCs.\n", nid);
+
 	edac_dbg(3, "Node %d: DRAM ECC %s.\n", nid, (ecc_en ? "enabled" : "disabled"));
 
-	if (!ecc_en || !nb_mce_en)
+	if (!ecc_en)
 		return false;
 	else
 		return true;
@@ -3678,6 +3685,7 @@ static void hw_info_put(struct amd64_pvt *pvt)
 
 static struct low_ops umc_ops = {
 	.hw_info_get			= umc_hw_info_get,
+	.ecc_enabled			= umc_ecc_enabled,
 };
 
 /* Use Family 16h versions for defaults and adjust as needed below. */
@@ -3685,6 +3693,7 @@ static struct low_ops dct_ops = {
 	.map_sysaddr_to_csrow		= f1x_map_sysaddr_to_csrow,
 	.dbam_to_cs			= f16_dbam_to_chip_select,
 	.hw_info_get			= dct_hw_info_get,
+	.ecc_enabled			= dct_ecc_enabled,
 };
 
 static int per_family_init(struct amd64_pvt *pvt)
@@ -3910,7 +3919,7 @@ static int probe_one_instance(unsigned int nid)
 		goto err_enable;
 	}
 
-	if (!ecc_enabled(pvt)) {
+	if (!pvt->ops->ecc_enabled(pvt)) {
 		ret = -ENODEV;
 
 		if (!ecc_enable_override)

drivers/edac/amd64_edac.h

@@ -467,6 +467,7 @@ struct low_ops {
 	int  (*dbam_to_cs)(struct amd64_pvt *pvt, u8 dct,
 			   unsigned int cs_mode, int cs_mask_nr);
 	int (*hw_info_get)(struct amd64_pvt *pvt);
+	bool (*ecc_enabled)(struct amd64_pvt *pvt);
 };
 
 int __amd64_read_pci_cfg_dword(struct pci_dev *pdev, int offset,