[PATCH v7 03/12] EDAC/mce_amd: Extract node id from MCA_IPID

[Naveen Krishna Chatradhi]

On SMCA banks of the GPU nodes, the node id information is
available in register MCA_IPID[47:44](InstanceIdHi).

Convert the hardware node ID to a value used by Linux
where GPU nodes are sequentially after the CPU nodes.

Co-developed-by: Muralidhara M K <muralimk@xxxxxxx>
Signed-off-by: Muralidhara M K <muralimk@xxxxxxx>
Signed-off-by: Naveen Krishna Chatradhi <nchatrad@xxxxxxx>
---
Link:
https://lkml.kernel.org/r/20211028130106.15701-3-nchatrad@xxxxxxx

v6->v7
* None

v5->v6:
* Called amd_get_gpu_node_id function to get node_id

v4->v5:
* None

v3->v4:
* Add reviewed by Yazen

v2->v3:
* Use APIs from amd_nb to identify the gpu_node_start_id and cpu_node_count.
  Which is required to map the hardware node id to node id enumerated by Linux.

v1->v2:
* Modified subject and commit message
* Added Reviewed by Yazen Ghannam

v0->v1:
* Modified the commit message
* Rearranged the conditions before calling decode_dram_ecc()


 drivers/edac/mce_amd.c | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
index cc5c63feb26a..865a925ccef0 100644
--- a/drivers/edac/mce_amd.c
+++ b/drivers/edac/mce_amd.c
@@ -2,6 +2,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 
+#include <asm/amd_nb.h>
 #include <asm/cpu.h>
 
 #include "mce_amd.h"
@@ -1186,8 +1187,26 @@ 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)
-		decode_dram_ecc(topology_die_id(m->extcpu), m);
+	if (xec == 0 && decode_dram_ecc) {
+		int node_id = 0;
+
+		if (bank_type == SMCA_UMC) {
+			node_id = topology_die_id(m->extcpu);
+		} else if (bank_type == SMCA_UMC_V2) {
+			/*
+			 * SMCA_UMC_V2 exists on GPU nodes, extract the node id
+			 * from register MCA_IPID[47:44](InstanceIdHi).
+			 * The InstanceIdHi field represents the instance ID of the GPU.
+			 * Which needs to be mapped to a value used by Linux,
+			 * where GPU nodes are simply numerically after the CPU nodes.
+			 */
+			node_id = amd_get_gpu_node_system_id(m->ipid);
+		} else {
+			return;
+		}
+
+		decode_dram_ecc(node_id, m);
+	}
 }
 
 static inline void amd_decode_err_code(u16 ec)
-- 
2.25.1