[PATCH v1 1/2] ufs: rpmb: retry power-on UNIT ATTENTION on the RPMB WLUN

[Jorge Ramirez-Ortiz]

After a power cycle, the first command sent to a UFS logical unit
completes with CHECK CONDITION and a power-on UNIT ATTENTION (ASC
0x29). The SCSI core reports this to the caller instead of retrying
it. For the RPMB well-known LU, that first command is the first RPMB
frame sent after boot, so the frame fails. RPMB has no earlier,
guaranteed access that could clear the condition beforehand, so this
breaks RPMB on every cold boot.

Ask the SCSI core to retry the power-on UNIT ATTENTION on the RPMB WLUN
so that RPMB works from the very first access after a power cycle.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez@xxxxxxxxxxxxxxxx>
---
 drivers/ufs/core/ufs-rpmb.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/ufs/core/ufs-rpmb.c b/drivers/ufs/core/ufs-rpmb.c
index ffad049872b9..d0c7ea7a36f4 100644
--- a/drivers/ufs/core/ufs-rpmb.c
+++ b/drivers/ufs/core/ufs-rpmb.c
@@ -40,6 +40,23 @@ struct ufs_rpmb_dev {
 static int ufs_sec_submit(struct ufs_hba *hba, u16 spsp, void *buffer, size_t len, bool send)
 {
 	struct scsi_device *sdev = hba->ufs_rpmb_wlun;
+	/* Retry the power-on UNIT ATTENTION (ASC 0x29); the SCSI core does not. */
+	struct scsi_failure failure_defs[] = {
+		{
+			.sense = UNIT_ATTENTION,
+			.asc = 0x29,
+			.ascq = SCMD_FAILURE_ASCQ_ANY,
+			.allowed = 3,
+			.result = SAM_STAT_CHECK_CONDITION,
+		},
+		{}
+	};
+	struct scsi_failures failures = {
+		.failure_definitions = failure_defs,
+	};
+	const struct scsi_exec_args exec_args = {
+		.failures = &failures,
+	};
 	u8 cdb[12] = { };
 
 	cdb[0] = send ? SECURITY_PROTOCOL_OUT : SECURITY_PROTOCOL_IN;
@@ -48,7 +65,8 @@ static int ufs_sec_submit(struct ufs_hba *hba, u16 spsp, void *buffer, size_t le
 	put_unaligned_be32(len, &cdb[6]);
 
 	return scsi_execute_cmd(sdev, cdb, send ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
-				buffer, len, /*timeout=*/30 * HZ, 0, NULL);
+				buffer, len, /*timeout=*/30 * HZ, /*retries=*/0,
+				&exec_args);
 }
 
 /* UFS RPMB route frames implementation */
-- 
2.54.0