return result;
}
+static int send_stop(struct mmc_card *card, u32 *status)
+{
+ struct mmc_command cmd = {0};
+ int err;
+
+ cmd.opcode = MMC_STOP_TRANSMISSION;
+ cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
+ err = mmc_wait_for_cmd(card->host, &cmd, 5);
+ if (err == 0)
+ *status = cmd.resp[0];
+ return err;
+}
+
static int get_card_status(struct mmc_card *card, u32 *status, int retries)
{
struct mmc_command cmd = {0};
return err;
}
+#define ERR_RETRY 2
+#define ERR_ABORT 1
+#define ERR_CONTINUE 0
+
+static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
+ bool status_valid, u32 status)
+{
+ switch (error) {
+ case -EILSEQ:
+ /* response crc error, retry the r/w cmd */
+ pr_err("%s: %s sending %s command, card status %#x\n",
+ req->rq_disk->disk_name, "response CRC error",
+ name, status);
+ return ERR_RETRY;
+
+ case -ETIMEDOUT:
+ pr_err("%s: %s sending %s command, card status %#x\n",
+ req->rq_disk->disk_name, "timed out", name, status);
+
+ /* If the status cmd initially failed, retry the r/w cmd */
+ if (!status_valid)
+ return ERR_RETRY;
+
+ /*
+ * If it was a r/w cmd crc error, or illegal command
+ * (eg, issued in wrong state) then retry - we should
+ * have corrected the state problem above.
+ */
+ if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND))
+ return ERR_RETRY;
+
+ /* Otherwise abort the command */
+ return ERR_ABORT;
+
+ default:
+ /* We don't understand the error code the driver gave us */
+ pr_err("%s: unknown error %d sending read/write command, card status %#x\n",
+ req->rq_disk->disk_name, error, status);
+ return ERR_ABORT;
+ }
+}
+
+/*
+ * Initial r/w and stop cmd error recovery.
+ * We don't know whether the card received the r/w cmd or not, so try to
+ * restore things back to a sane state. Essentially, we do this as follows:
+ * - Obtain card status. If the first attempt to obtain card status fails,
+ * the status word will reflect the failed status cmd, not the failed
+ * r/w cmd. If we fail to obtain card status, it suggests we can no
+ * longer communicate with the card.
+ * - Check the card state. If the card received the cmd but there was a
+ * transient problem with the response, it might still be in a data transfer
+ * mode. Try to send it a stop command. If this fails, we can't recover.
+ * - If the r/w cmd failed due to a response CRC error, it was probably
+ * transient, so retry the cmd.
+ * - If the r/w cmd timed out, but we didn't get the r/w cmd status, retry.
+ * - If the r/w cmd timed out, and the r/w cmd failed due to CRC error or
+ * illegal cmd, retry.
+ * Otherwise we don't understand what happened, so abort.
+ */
+static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
+ struct mmc_blk_request *brq)
+{
+ bool prev_cmd_status_valid = true;
+ u32 status, stop_status = 0;
+ int err, retry;
+
+ /*
+ * Try to get card status which indicates both the card state
+ * and why there was no response. If the first attempt fails,
+ * we can't be sure the returned status is for the r/w command.
+ */
+ for (retry = 2; retry >= 0; retry--) {
+ err = get_card_status(card, &status, 0);
+ if (!err)
+ break;
+
+ prev_cmd_status_valid = false;
+ pr_err("%s: error %d sending status command, %sing\n",
+ req->rq_disk->disk_name, err, retry ? "retry" : "abort");
+ }
+
+ /* We couldn't get a response from the card. Give up. */
+ if (err)
+ return ERR_ABORT;
+
+ /*
+ * Check the current card state. If it is in some data transfer
+ * mode, tell it to stop (and hopefully transition back to TRAN.)
+ */
+ if (R1_CURRENT_STATE(status) == R1_STATE_DATA ||
+ R1_CURRENT_STATE(status) == R1_STATE_RCV) {
+ err = send_stop(card, &stop_status);
+ if (err)
+ pr_err("%s: error %d sending stop command\n",
+ req->rq_disk->disk_name, err);
+
+ /*
+ * If the stop cmd also timed out, the card is probably
+ * not present, so abort. Other errors are bad news too.
+ */
+ if (err)
+ return ERR_ABORT;
+ }
+
+ /* Check for set block count errors */
+ if (brq->sbc.error)
+ return mmc_blk_cmd_error(req, "SET_BLOCK_COUNT", brq->sbc.error,
+ prev_cmd_status_valid, status);
+
+ /* Check for r/w command errors */
+ if (brq->cmd.error)
+ return mmc_blk_cmd_error(req, "r/w cmd", brq->cmd.error,
+ prev_cmd_status_valid, status);
+
+ /* Now for stop errors. These aren't fatal to the transfer. */
+ pr_err("%s: error %d sending stop command, original cmd response %#x, card status %#x\n",
+ req->rq_disk->disk_name, brq->stop.error,
+ brq->cmd.resp[0], status);
+
+ /*
+ * Subsitute in our own stop status as this will give the error
+ * state which happened during the execution of the r/w command.
+ */
+ if (stop_status) {
+ brq->stop.resp[0] = stop_status;
+ brq->stop.error = 0;
+ }
+ return ERR_CONTINUE;
+}
+
static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
{
struct mmc_blk_data *md = mq->data;
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
struct mmc_blk_request brq;
- int ret = 1, disable_multi = 0;
+ int ret = 1, disable_multi = 0, retry = 0;
/*
* Reliable writes are used to implement Forced Unit Access and
(md->flags & MMC_BLK_REL_WR);
do {
- u32 readcmd, writecmd, status = 0;
+ u32 readcmd, writecmd;
memset(&brq, 0, sizeof(struct mmc_blk_request));
brq.mrq.cmd = &brq.cmd;
mmc_queue_bounce_post(mq);
/*
- * Check for errors here, but don't jump to cmd_err
- * until later as we need to wait for the card to leave
- * programming mode even when things go wrong.
+ * sbc.error indicates a problem with the set block count
+ * command. No data will have been transferred.
+ *
+ * cmd.error indicates a problem with the r/w command. No
+ * data will have been transferred.
+ *
+ * stop.error indicates a problem with the stop command. Data
+ * may have been transferred, or may still be transferring.
*/
- if (brq.sbc.error || brq.cmd.error ||
- brq.data.error || brq.stop.error) {
- if (brq.data.blocks > 1 && rq_data_dir(req) == READ) {
- /* Redo read one sector at a time */
- printk(KERN_WARNING "%s: retrying using single "
- "block read\n", req->rq_disk->disk_name);
- disable_multi = 1;
- continue;
+ if (brq.sbc.error || brq.cmd.error || brq.stop.error) {
+ switch (mmc_blk_cmd_recovery(card, req, &brq)) {
+ case ERR_RETRY:
+ if (retry++ < 5)
+ continue;
+ case ERR_ABORT:
+ goto cmd_abort;
+ case ERR_CONTINUE:
+ break;
}
- get_card_status(card, &status, 0);
- }
-
- if (brq.sbc.error) {
- printk(KERN_ERR "%s: error %d sending SET_BLOCK_COUNT "
- "command, response %#x, card status %#x\n",
- req->rq_disk->disk_name, brq.sbc.error,
- brq.sbc.resp[0], status);
- }
-
- if (brq.cmd.error) {
- printk(KERN_ERR "%s: error %d sending read/write "
- "command, response %#x, card status %#x\n",
- req->rq_disk->disk_name, brq.cmd.error,
- brq.cmd.resp[0], status);
- }
-
- if (brq.data.error) {
- if (brq.data.error == -ETIMEDOUT && brq.mrq.stop)
- /* 'Stop' response contains card status */
- status = brq.mrq.stop->resp[0];
- printk(KERN_ERR "%s: error %d transferring data,"
- " sector %u, nr %u, card status %#x\n",
- req->rq_disk->disk_name, brq.data.error,
- (unsigned)blk_rq_pos(req),
- (unsigned)blk_rq_sectors(req), status);
- }
-
- if (brq.stop.error) {
- printk(KERN_ERR "%s: error %d sending stop command, "
- "response %#x, card status %#x\n",
- req->rq_disk->disk_name, brq.stop.error,
- brq.stop.resp[0], status);
}
if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
+ u32 status;
do {
int err = get_card_status(card, &status, 5);
if (err) {
(R1_CURRENT_STATE(status) == R1_STATE_PRG));
}
- if (brq.cmd.error || brq.stop.error || brq.data.error) {
+ if (brq.data.error) {
+ pr_err("%s: error %d transferring data, sector %u nr %u, cmd response %#x card status %#x\n",
+ req->rq_disk->disk_name, brq.data.error,
+ (unsigned)blk_rq_pos(req),
+ (unsigned)blk_rq_sectors(req),
+ brq.cmd.resp[0], brq.stop.resp[0]);
+
if (rq_data_dir(req) == READ) {
+ if (brq.data.blocks > 1) {
+ /* Redo read one sector at a time */
+ pr_warning("%s: retrying using single block read\n",
+ req->rq_disk->disk_name);
+ disable_multi = 1;
+ continue;
+ }
+
/*
* After an error, we redo I/O one sector at a
* time, so we only reach here after trying to
ret = __blk_end_request(req, -EIO, brq.data.blksz);
spin_unlock_irq(&md->lock);
continue;
+ } else {
+ goto cmd_err;
}
- goto cmd_err;
}
/*
spin_unlock_irq(&md->lock);
}
+ cmd_abort:
spin_lock_irq(&md->lock);
while (ret)
ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));