[PATCH 7/7] EDAC/amd64: Add Error address conversion for UMC

[Muralidhara M K]

From: Muralidhara M K <muralidhara.mk@xxxxxxx>

Reported MCA address is DRAM address which needs to be converted
to normalized address before Data fabric address translation.

Some AMD systems have on-chip memory capable of OnDie ECC support.
OnDie-ECC error address to MCA is a DRAM decoded address reported with
a DRAM address (PC/SID/Bank/ROW/COL) instead of normalized address
unlike MI200’s UMC ECC, as the implementation difference between
HBM3 ODECC and HBM2 host ECC.
Because OnDie-ECC address reporting is done in the back-end of UMC and
it no longer has normalized address at that point.
So software needs to convert the reported MCA Error Address back to
normalized address.

Signed-off-by: Muralidhara M K <muralidhara.mk@xxxxxxx>
---
 drivers/edac/amd64_edac.c | 160 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 160 insertions(+)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 74b2b47cc22a..304d104c25d8 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -3076,6 +3076,159 @@ static void umc_get_err_info(struct mce *m, struct err_info *err)
 	err->csrow = m->synd & 0x7;
 }
 
+static bool internal_bit_wise_xor(u32 inp)
+{
+	bool tmp = 0;
+
+	for (int i = 0; i < 32; i++)
+		tmp = tmp ^ ((inp >> i) & 0x1);
+
+	return tmp;
+}
+
+/* mapping of MCA error address to normalized address */
+static const u8 umc_mca2na_mapping[] = {
+	0,  5,  6,  8,  9,  14, 12, 13,
+	10, 11, 15, 16, 17, 18, 19, 20,
+	21, 22, 23, 24, 25, 26, 27, 28,
+	7,  29, 30,
+};
+
+/*
+ * Read AMD PPR UMC::AddrHashBank and
+ * UMC::CH::AddrHashPC/PC2 register fields
+ */
+static struct {
+	u32 xor_enable	:1;
+	u32 col_xor	:13;
+	u32 row_xor	:18;
+} addr_hash_pc, addr_hash_bank[4];
+
+static struct {
+	u32 bank_xor	:6;
+} addr_hash_pc2;
+
+/*
+ * The location of bank, column and row are fixed.
+ * location of column bit must be NA[5].
+ * Row bits are always placed in a contiguous stretch of NA above the
+ * column and bank bits.
+ * Bits below the row bits can be either column or bank in any order,
+ * with the exception that NA[5] must be a column bit.
+ * Stack ID(SID) bits are placed in the MSB position of the NA.
+ */
+static int umc_ondie_addr_to_normaddr(u64 mca_addr, u16 nid)
+{
+	u32 bank[4], bank_hash[4], pc_hash;
+	u32 col, row, rawbank = 0, pc;
+	int i, temp = 0;
+	u64 mca2na;
+
+	u32 gpu_umc_base = 0x90000;
+
+	/*
+	 * the below calculation, trying to maps ondie error address
+	 * to normalized address. logged ondie MCA address format is
+	 * BEQ_MCA_RdDatAddr[27:0] =
+	 *	{SID[1:0],PC[0],row[14:0],bank[3:0],col[4:0],1'b0}
+	 * The conversion mappings are:
+	 *
+	 * Normalized location	  ondie MCA error Address
+	 * ===================	  ======================
+	 * NA[4]		  = 1'b0
+	 * NA[5]	= col[0]  = BEQ_MCA_RdDatAddr[1]
+	 * NA[6]	= col[1]  = BEQ_MCA_RdDatAddr[2]
+	 * NA[8]	= col[2]  = BEQ_MCA_RdDatAddr[3]
+	 * NA[9]	= col[3]  = BEQ_MCA_RdDatAddr[4]
+	 * NA[14]	= col[4]  = BEQ_MCA_RdDatAddr[5]
+	 * NA[12]	= bank[0] = BEQ_MCA_RdDatAddr[5]
+	 * NA[13]	= bank[1] = BEQ_MCA_RdDatAddr[6]
+	 * NA[10]	= bank[2] = BEQ_MCA_RdDatAddr[7]
+	 * NA[11]	= bank[3] = BEQ_MCA_RdDatAddr[8]
+	 *
+	 * row low is 12 bit locations, low lsb bit starts from 10
+	 * NA[15..26] = row[0..11]  = BEQ_MCA_RdDatAddr[10..21]
+	 *
+	 * row high is 2 bit locations, high lsb bit starts from 22
+	 * NA[27..28] = row[12..13] = BEQ_MCA_RdDatAddr[22..23]
+	 *
+	 * NA[7]	= PC[0]   = BEQ_MCA_RdDatAddr[25]
+	 * NA[29]	= sid[0]  = bank[4] = BEQ_MCA_RdDatAddr[26]
+	 * NA[30]	= sid[1]  = bank[5] = BEQ_MCA_RdDatAddr[27]
+	 * Basically, it calculates a locations to fit as shown in
+	 * table umc_mca2na_mapping[].
+	 *
+	 * XORs need to be applied based on the hash settings below.
+	 */
+
+	/* Calculate column and row */
+	col = FIELD_GET(GENMASK(5, 1), mca_addr);
+	row = FIELD_GET(GENMASK(23, 10), mca_addr);
+
+	/* Apply hashing on below banks for bank calculation */
+	for (i = 0; i < 4; i++)
+		bank_hash[i] = (mca_addr >> (6 + i)) & 0x1;
+
+	/* bank hash algorithm */
+	for (i = 0; i < 4; i++) {
+		/* Read AMD PPR UMC::AddrHashBank register*/
+		if (!amd_smn_read(nid, gpu_umc_base + 0xC8 + (i * 4), &temp)) {
+			addr_hash_bank[i].xor_enable = temp & 1;
+			addr_hash_bank[i].col_xor = FIELD_GET(GENMASK(13, 1), temp);
+			addr_hash_bank[i].row_xor = FIELD_GET(GENMASK(31, 14), temp);
+			/* bank hash selection */
+			bank[i] = bank_hash[i] ^ (addr_hash_bank[i].xor_enable &
+				  (internal_bit_wise_xor(col & addr_hash_bank[i].col_xor) ^
+				  internal_bit_wise_xor(row & addr_hash_bank[i].row_xor)));
+		}
+	}
+
+	/* To apply hash on pc bit */
+	pc_hash = (mca_addr >> 25) & 0x1;
+
+	/* Read AMD PPR UMC::CH::AddrHashPC register */
+	if (!amd_smn_read(nid, gpu_umc_base + 0xE0, &temp)) {
+		addr_hash_pc.xor_enable = temp & 1;
+		addr_hash_pc.col_xor = FIELD_GET(GENMASK(13, 1), temp);
+		addr_hash_pc.row_xor = FIELD_GET(GENMASK(31, 14), temp);
+	}
+	/* Read AMD PPR UMC::CH::AddrHashPC2 register*/
+	if (!amd_smn_read(nid, gpu_umc_base + 0xE4, &temp))
+		addr_hash_pc2.bank_xor = FIELD_GET(GENMASK(5, 0), temp);
+
+	/* Calculate bank value from bank[0..3], bank[4] and bank[5] */
+	for (i = 0; i < 4; i++)
+		rawbank |= (bank[i] & 1) << i;
+
+	rawbank |= (mca_addr >> 22) & 0x30;
+
+	/* pseudochannel(pc) hash selection */
+	pc = pc_hash ^ (addr_hash_pc.xor_enable &
+		(internal_bit_wise_xor(col & addr_hash_pc.col_xor) ^
+		internal_bit_wise_xor(row & addr_hash_pc.row_xor) ^
+		internal_bit_wise_xor(rawbank & addr_hash_pc2.bank_xor)));
+
+	/* Mask b'25(pc_bit) and b'[9:6](bank) */
+	mca_addr &= ~0x20003c0ULL;
+
+	for (i = 0; i < 4; i++)
+		mca_addr |= (bank[i] << (6 + i));
+
+	 mca_addr |= (pc << 25);
+
+	/* NA[4..0] is fixed */
+	mca2na = 0x0;
+	/* convert mca error address to normalized address */
+	for (i = 1; i < ARRAY_SIZE(umc_mca2na_mapping); i++)
+		mca2na |= ((mca_addr >> i) & 0x1) << umc_mca2na_mapping[i];
+
+	mca_addr = mca2na;
+	pr_emerg(HW_ERR "Error Addr: 0x%016llx\n", mca_addr);
+	pr_emerg(HW_ERR "Error hit on Bank: %d Row: %d Column: %d\n", rawbank, row, col);
+
+	return mca_addr;
+}
+
 static void decode_umc_error(int node_id, struct mce *m)
 {
 	u8 ecc_type = (m->status >> 45) & 0x3;
@@ -3115,6 +3268,13 @@ static void decode_umc_error(int node_id, struct mce *m)
 	pvt->ops->get_err_info(m, &err);
 	df_inst_id = pvt->ops->get_inst_id(mci, pvt, &err);
 
+	/*
+	 * The reported MCA address(Error Addr) is DRAM decoded address which needs to be
+	 * converted to normalized address before DF address translation.
+	 */
+	if (pvt->fam == 0x19 && (pvt->model >= 0x90 && pvt->model <= 0x9f))
+		m->addr = umc_ondie_addr_to_normaddr(m->addr, pvt->mc_node_id);
+
 	if (umc_normaddr_to_sysaddr(m->addr, pvt->mc_node_id, df_inst_id, &sys_addr)) {
 		err.err_code = ERR_NORM_ADDR;
 		goto log_error;
-- 
2.25.1