[PATCH v2 03/31] EDAC/amd64: Don't use naked values for DF registers

[Yazen Ghannam]

AMD Data Fabric registers are defined using a combination of PCI
function number and offset. Define a struct to hold these values, and
update the DF Indirect Access function to accept a struct of this type.

Update the address translation code to include a list of the needed DF
registers using this new format. Define an enumeration to give the
registers more human-readable names.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
Link:
https://lkml.kernel.org/r/20210507190140.18854-2-Yazen.Ghannam@xxxxxxx

v1->v2:
* Moved from arch/x86 to EDAC.

 drivers/edac/amd64_edac.c | 60 ++++++++++++++++++++++++++++++---------
 1 file changed, 47 insertions(+), 13 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index e9342d7d693f..b94067e3952b 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -996,6 +996,11 @@ static int sys_addr_to_csrow(struct mem_ctl_info *mci, u64 sys_addr)
 /* Protect the PCI config register pairs used for DF indirect access. */
 static DEFINE_MUTEX(df_indirect_mutex);
 
+struct df_reg {
+	u8 func;
+	u16 offset;
+};
+
 /*
  * Data Fabric Indirect Access uses FICAA/FICAD.
  *
@@ -1006,7 +1011,7 @@ static DEFINE_MUTEX(df_indirect_mutex);
  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
  * and FICAD HI registers but so far we only need the LO register.
  */
-static int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
+static int amd_df_indirect_read(u16 node, struct df_reg reg, u8 instance_id, u32 *lo)
 {
 	struct pci_dev *F4;
 	u32 ficaa;
@@ -1020,8 +1025,8 @@ static int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32
 		goto out;
 
 	ficaa  = 1;
-	ficaa |= reg & 0x3FC;
-	ficaa |= (func & 0x7) << 11;
+	ficaa |= reg.offset & 0x3FC;
+	ficaa |= (reg.func & 0x7) << 11;
 	ficaa |= instance_id << 16;
 
 	mutex_lock(&df_indirect_mutex);
@@ -1043,6 +1048,33 @@ static int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32
 	return err;
 }
 
+enum df_reg_names {
+	/* Function 0 */
+	FAB_BLK_INST_INFO_3,
+	DRAM_HOLE_CTL,
+	DRAM_BASE_ADDR,
+	DRAM_LIMIT_ADDR,
+	DRAM_OFFSET,
+
+	/* Function 1 */
+	SYS_FAB_ID_MASK,
+};
+
+static struct df_reg df_regs[] = {
+	/* D18F0x50 (FabricBlockInstanceInformation3_CS) */
+	[FAB_BLK_INST_INFO_3]	=	{0, 0x50},
+	/* D18F0x104 (DramHoleControl) */
+	[DRAM_HOLE_CTL]		=	{0, 0x104},
+	/* D18F0x110 (DramBaseAddress) */
+	[DRAM_BASE_ADDR]	=	{0, 0x110},
+	/* D18F0x114 (DramLimitAddress) */
+	[DRAM_LIMIT_ADDR]	=	{0, 0x114},
+	/* D18F0x1B4 (DramOffset) */
+	[DRAM_OFFSET]		=	{0, 0x1B4},
+	/* D18F1x208 (SystemFabricIdMask) */
+	[SYS_FAB_ID_MASK]	=	{1, 0x208},
+};
+
 static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 {
 	u64 dram_base_addr, dram_limit_addr, dram_hole_base;
@@ -1059,8 +1091,9 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 	u8 cs_mask, cs_id = 0;
 	bool hash_enabled = false;
 
-	/* Read D18F0x1B4 (DramOffset), check if base 1 is used. */
-	if (amd_df_indirect_read(nid, 0, 0x1B4, umc, &tmp))
+	struct df_reg reg;
+
+	if (amd_df_indirect_read(nid, df_regs[DRAM_OFFSET], umc, &tmp))
 		goto out_err;
 
 	/* Remove HiAddrOffset from normalized address, if enabled: */
@@ -1073,8 +1106,9 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 		}
 	}
 
-	/* Read D18F0x110 (DramBaseAddress). */
-	if (amd_df_indirect_read(nid, 0, 0x110 + (8 * base), umc, &tmp))
+	reg = df_regs[DRAM_BASE_ADDR];
+	reg.offset += base * 8;
+	if (amd_df_indirect_read(nid, reg, umc, &tmp))
 		goto out_err;
 
 	/* Check if address range is valid. */
@@ -1096,8 +1130,9 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 		goto out_err;
 	}
 
-	/* Read D18F0x114 (DramLimitAddress). */
-	if (amd_df_indirect_read(nid, 0, 0x114 + (8 * base), umc, &tmp))
+	reg = df_regs[DRAM_LIMIT_ADDR];
+	reg.offset += base * 8;
+	if (amd_df_indirect_read(nid, reg, umc, &tmp))
 		goto out_err;
 
 	intlv_num_sockets = (tmp >> 8) & 0x1;
@@ -1153,7 +1188,7 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 		 * umc/channel# as instance id of the coherent slave
 		 * for FICAA.
 		 */
-		if (amd_df_indirect_read(nid, 0, 0x50, umc, &tmp))
+		if (amd_df_indirect_read(nid, df_regs[FAB_BLK_INST_INFO_3], umc, &tmp))
 			goto out_err;
 
 		cs_fabric_id = (tmp >> 8) & 0xFF;
@@ -1168,9 +1203,8 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 
 		sock_id_bit = die_id_bit;
 
-		/* Read D18F1x208 (SystemFabricIdMask). */
 		if (intlv_num_dies || intlv_num_sockets)
-			if (amd_df_indirect_read(nid, 1, 0x208, umc, &tmp))
+			if (amd_df_indirect_read(nid, df_regs[SYS_FAB_ID_MASK], umc, &tmp))
 				goto out_err;
 
 		/* If interleaved over more than 1 die. */
@@ -1209,7 +1243,7 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr
 
 	/* If legacy MMIO hole enabled */
 	if (lgcy_mmio_hole_en) {
-		if (amd_df_indirect_read(nid, 0, 0x104, umc, &tmp))
+		if (amd_df_indirect_read(nid, df_regs[DRAM_HOLE_CTL], umc, &tmp))
 			goto out_err;
 
 		dram_hole_base = tmp & GENMASK(31, 24);
-- 
2.25.1