fix(ufs): retry commands on unit attention
Unit Attention Condition (UAC) gets set on a warm reset. Sending any
command (other than INQUIRY and REPORT LUNs) clears UAC, so its good to
add some retries when UAC is encountered
Signed-off-by: Anand Saminathan <anans@google.com>
Change-Id: Ia03b916d68565d0f3d25086b7f6d8c51d557b64f
diff --git a/drivers/ufs/ufs.c b/drivers/ufs/ufs.c
index 754d173..d8c0a14 100644
--- a/drivers/ufs/ufs.c
+++ b/drivers/ufs/ufs.c
@@ -477,6 +477,7 @@
{
utrd_header_t *hd;
resp_upiu_t *resp;
+ sense_data_t *sense;
unsigned int data;
int slot;
@@ -499,6 +500,15 @@
inv_dcache_range((uintptr_t)hd, UFS_DESC_SIZE);
assert(hd->ocs == OCS_SUCCESS);
assert((resp->trans_type & TRANS_TYPE_CODE_MASK) == trans_type);
+
+ sense = &resp->sd.sense;
+ if (sense->resp_code == SENSE_DATA_VALID &&
+ sense->sense_key == SENSE_KEY_UNIT_ATTENTION && sense->asc == 0x29 &&
+ sense->ascq == 0) {
+ WARN("Unit Attention Condition\n");
+ return -EAGAIN;
+ }
+
(void)resp;
(void)slot;
return 0;
@@ -507,14 +517,18 @@
static void ufs_send_cmd(utp_utrd_t *utrd, uint8_t cmd_op, uint8_t lun, int lba, uintptr_t buf,
size_t length)
{
- int result;
-
- get_utrd(utrd);
+ int result, i;
- result = ufs_prepare_cmd(utrd, cmd_op, lun, lba, buf, length);
- assert(result == 0);
- ufs_send_request(utrd->task_tag);
- result = ufs_check_resp(utrd, RESPONSE_UPIU);
+ for (i = 0; i < UFS_CMD_RETRIES; ++i) {
+ get_utrd(utrd);
+ result = ufs_prepare_cmd(utrd, cmd_op, lun, lba, buf, length);
+ assert(result == 0);
+ ufs_send_request(utrd->task_tag);
+ result = ufs_check_resp(utrd, RESPONSE_UPIU);
+ if (result == 0 || result == -EIO) {
+ break;
+ }
+ }
assert(result == 0);
(void)result;
}