scsi: ufs: core: Exclude UECxx from SFR dump list

[ Upstream commit ef60031 ]

Some devices may return invalid or zeroed data during an UIC error
condition. In addition, reading these SFRs will clear them. This means the
subsequent error handling will not be able to see them and therefore no
error handling will be scheduled.

Skip reading these SFRs in ufshcd_dump_regs().

Link: https://lore.kernel.org/r/1648689845-33521-1-git-send-email-kwmad.kim@samsung.com
Fixes: d672475 ("scsi: ufs: Use explicit access size in ufshcd_dump_regs")
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/scsi/ufs/ufshcd.c

@@ -112,8 +112,13 @@ int ufshcd_dump_regs(struct ufs_hba *hba, size_t offset, size_t len,
 	if (!regs)
 		return -ENOMEM;
 
-	for (pos = 0; pos < len; pos += 4)
+	for (pos = 0; pos < len; pos += 4) {
+		if (offset == 0 &&
+		    pos >= REG_UIC_ERROR_CODE_PHY_ADAPTER_LAYER &&
+		    pos <= REG_UIC_ERROR_CODE_DME)
+			continue;
 		regs[pos / 4] = ufshcd_readl(hba, offset + pos);
+	}
 
 	ufshcd_hex_dump(prefix, regs, len);
 	kfree(regs);