commit 854364ba44aee9bc5646f6537fc744b0b54aff37
Author: Muralidhara M K <muralimk@amd.com>
Date:   Thu Aug 20 21:00:57 2020 +0530

    rasdaemon: Add 8 channel decoding for SMCA systems
    
    Current Scalable Machine Check Architecture (SMCA) systems support up
    to 8 UMC channels.
    
    To find the UMC channel represented by a bank, look at the 6th nibble
    in the MCA_IPID[InstanceId] field.
    
    Signed-off-by: Muralidhara M K <muralimk@amd.com>
    [ Adjust commit message. ]
    Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
    Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/mce-amd-smca.c b/mce-amd-smca.c
index d0b6cb6..7c619fd 100644
--- a/mce-amd-smca.c
+++ b/mce-amd-smca.c
@@ -438,15 +438,7 @@ static void amd_decode_errcode(struct mce_event *e)
  */
 static int find_umc_channel(struct mce_event *e)
 {
-	uint32_t umc_instance_id[] = {0x50f00, 0x150f00};
-	uint32_t instance_id = EXTRACT(e->ipid, 0, 31);
-	int i, channel = -1;
-
-	for (i = 0; i < ARRAY_SIZE(umc_instance_id); i++)
-		if (umc_instance_id[i] == instance_id)
-			channel = i;
-
-	return channel;
+	return EXTRACT(e->ipid, 0, 31) >> 20;
 }
 /* Decode extended errors according to Scalable MCA specification */
 static void decode_smca_error(struct mce_event *e)