[PATCH 2/5] x86/MCE/AMD, EDAC/mce_amd: Decode UMC_V2 ECC errors

From: Muralidhara M K
Date: Mon May 15 2023 - 07:40:20 EST


From: Yazen Ghannam <yazen.ghannam@xxxxxxx>

The MI200 (Aldebaran) series of devices introduced a new SMCA bank type
for Unified Memory Controllers. The MCE subsystem already has support
for this new type. The MCE decoder module will decode the common MCA
error information for the new bank type, but it will not pass the
information to the AMD64 EDAC module for detailed memory error decoding.

Have the MCE decoder module recognize the new bank type as an SMCA UMC
memory error and pass the MCA information to AMD64 EDAC.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
Co-developed-by: Muralidhara M K <muralidhara.mk@xxxxxxx>
Signed-off-by: Muralidhara M K <muralidhara.mk@xxxxxxx>
---
arch/x86/kernel/cpu/mce/amd.c | 6 ++++--
drivers/edac/mce_amd.c | 3 ++-
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 0b971f974096..5e74610b39e7 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -715,11 +715,13 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)

bool amd_mce_is_memory_error(struct mce *m)
{
+ enum smca_bank_types bank_type;
/* ErrCodeExt[20:16] */
u8 xec = (m->status >> 16) & 0x1f;

+ bank_type = smca_get_bank_type(m->extcpu, m->bank);
if (mce_flags.smca)
- return smca_get_bank_type(m->extcpu, m->bank) == SMCA_UMC && xec == 0x0;
+ return (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2) && xec == 0x0;

return m->bank == 4 && xec == 0x8;
}
@@ -1050,7 +1052,7 @@ static const char *get_name(unsigned int cpu, unsigned int bank, struct threshol
if (bank_type >= N_SMCA_BANK_TYPES)
return NULL;

- if (b && bank_type == SMCA_UMC) {
+ if (b && (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2)) {
if (b->block < ARRAY_SIZE(smca_umc_block_names))
return smca_umc_block_names[b->block];
return NULL;
diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
index cc5c63feb26a..9215c06783df 100644
--- a/drivers/edac/mce_amd.c
+++ b/drivers/edac/mce_amd.c
@@ -1186,7 +1186,8 @@ static void decode_smca_error(struct mce *m)
if (xec < smca_mce_descs[bank_type].num_descs)
pr_cont(", %s.\n", smca_mce_descs[bank_type].descs[xec]);

- if (bank_type == SMCA_UMC && xec == 0 && decode_dram_ecc)
+ if ((bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2) &&
+ xec == 0 && decode_dram_ecc)
decode_dram_ecc(topology_die_id(m->extcpu), m);
}

--
2.25.1