EDAC/{skx_common,i10nm}: Fix some missing error reports on Emerald Rapids

When doing error injection to some memory DIMMs on certain Intel Emerald
Rapids servers, the i10nm_edac missed error reports for some memory DIMMs.

Certain BIOS configurations may hide some memory controllers, and the
i10nm_edac doesn't enumerate these hidden memory controllers. However, the
ADXL decodes memory errors using memory controller physical indices even
if there are hidden memory controllers. Therefore, the memory controller
physical indices reported by the ADXL may mismatch the logical indices
enumerated by the i10nm_edac, resulting in missed error reports for some
memory DIMMs.

Fix this issue by creating a mapping table from memory controller physical
indices (used by the ADXL) to logical indices (used by the i10nm_edac) and
using it to convert the physical indices to the logical indices during the
error handling process.

Fixes: c545f5e41225 ("EDAC/i10nm: Skip the absent memory controllers")
Reported-by: Kevin Chang <kevin1.chang@intel.com>
Tested-by: Kevin Chang <kevin1.chang@intel.com>
Reported-by: Thomas Chen <Thomas.Chen@intel.com>
Tested-by: Thomas Chen <Thomas.Chen@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250214002728.6287-1-qiuxu.zhuo@intel.com

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index f7bd930e058fe..fa5b442b18449 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -121,6 +121,35 @@ void skx_adxl_put(void)
 }
 EXPORT_SYMBOL_GPL(skx_adxl_put);
 
+static void skx_init_mc_mapping(struct skx_dev *d)
+{
+	/*
+	 * By default, the BIOS presents all memory controllers within each
+	 * socket to the EDAC driver. The physical indices are the same as
+	 * the logical indices of the memory controllers enumerated by the
+	 * EDAC driver.
+	 */
+	for (int i = 0; i < NUM_IMC; i++)
+		d->mc_mapping[i] = i;
+}
+
+void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc)
+{
+	edac_dbg(0, "Set the mapping of mc phy idx to logical idx: %02d -> %02d\n",
+		 pmc, lmc);
+
+	d->mc_mapping[pmc] = lmc;
+}
+EXPORT_SYMBOL_GPL(skx_set_mc_mapping);
+
+static u8 skx_get_mc_mapping(struct skx_dev *d, u8 pmc)
+{
+	edac_dbg(0, "Get the mapping of mc phy idx to logical idx: %02d -> %02d\n",
+		 pmc, d->mc_mapping[pmc]);
+
+	return d->mc_mapping[pmc];
+}
+
 static bool skx_adxl_decode(struct decoded_addr *res, enum error_source err_src)
 {
 	struct skx_dev *d;
@@ -188,6 +217,8 @@ static bool skx_adxl_decode(struct decoded_addr *res, enum error_source err_src)
 		return false;
 	}
 
+	res->imc = skx_get_mc_mapping(d, res->imc);
+
 	for (i = 0; i < adxl_component_count; i++) {
 		if (adxl_values[i] == ~0x0ull)
 			continue;
@@ -326,6 +357,8 @@ int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list)
 			 d->bus[0], d->bus[1], d->bus[2], d->bus[3]);
 		list_add_tail(&d->list, &dev_edac_list);
 		prev = pdev;
+
+		skx_init_mc_mapping(d);
 	}
 
 	if (list)