[PATCH v2 09/22] EDAC/amd64: Don't find ECC symbol size for Family 17h and later

From: Yazen Ghannam
Date: Fri Jan 27 2023 - 12:05:39 EST


The ECC symbol size was needed on legacy system to lookup the ECC syndrome.
This is not needed on modern systems because the ECC syndrome is explicitly
provided in the MCA information.

Remove the ECC symbol size discovery code for modern UMC-based systems.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
Link:
https://lore.kernel.org/r/20220509145534.44912-10-yazen.ghannam@xxxxxxx

v1->v2:
* New in v2.
* Replaces v1 patch 9.

drivers/edac/amd64_edac.c | 21 +++------------------
1 file changed, 3 insertions(+), 18 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index e13fe400bad5..1d5c2c97d563 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -1600,6 +1600,8 @@ static void __dump_misc_regs(struct amd64_pvt *pvt)
debug_dump_dramcfg_low(pvt, pvt->dclr1, 1);

edac_dbg(1, " DramHoleValid: %s\n", dhar_valid(pvt) ? "yes" : "no");
+
+ amd64_info("using x%u syndromes.\n", pvt->ecc_sym_sz);
}

/* Display and decode various NB registers for debug purposes. */
@@ -1609,8 +1611,6 @@ static void dump_misc_regs(struct amd64_pvt *pvt)
__dump_misc_regs_df(pvt);
else
__dump_misc_regs(pvt);
-
- amd64_info("using x%u syndromes.\n", pvt->ecc_sym_sz);
}

/*
@@ -3197,22 +3197,7 @@ static void determine_ecc_sym_sz(struct amd64_pvt *pvt)
{
pvt->ecc_sym_sz = 4;

- if (pvt->umc) {
- u8 i;
-
- for_each_umc(i) {
- /* Check enabled channels only: */
- if (pvt->umc[i].sdp_ctrl & UMC_SDP_INIT) {
- if (pvt->umc[i].ecc_ctrl & BIT(9)) {
- pvt->ecc_sym_sz = 16;
- return;
- } else if (pvt->umc[i].ecc_ctrl & BIT(7)) {
- pvt->ecc_sym_sz = 8;
- return;
- }
- }
- }
- } else if (pvt->fam >= 0x10) {
+ if (pvt->fam >= 0x10) {
u32 tmp;

amd64_read_pci_cfg(pvt->F3, EXT_NB_MCA_CFG, &tmp);
--
2.25.1