there is a time window between __mmc_send_status() and time_afer(),
on some eMMC chip, the timeout_ms is only 10ms, if this thread was
scheduled out during this period, then, even card has already changes
to transfer state by the result of CMD13, this part of code also treat
it to timeout error.
So, need calculate timeout first, then call __mmc_send_status(), if
already timeout and card still in programing state, then treat it to
the real timeout error.
Signed-off-by: Chaotian Jing <[email protected]>
---
drivers/mmc/core/mmc_ops.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 1f44426..371aa4b 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -489,6 +489,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
unsigned long timeout;
u32 status = 0;
bool use_r1b_resp = use_busy_signal;
+ bool expired = false;
mmc_retune_hold(host);
@@ -544,6 +545,12 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
/* Must check status to be sure of no errors. */
timeout = jiffies + msecs_to_jiffies(timeout_ms);
do {
+ /*
+ * Due to the possibility of being preempted after sending the
+ * status command, check the expiration time first.
+ */
+ expired = time_after(jiffies, timeout);
+
if (send_status) {
err = __mmc_send_status(card, &status, ignore_crc);
if (err)
@@ -565,12 +572,13 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
}
/* Timeout if the device never leaves the program state. */
- if (time_after(jiffies, timeout)) {
+ if (expired && R1_CURRENT_STATE(status) == R1_STATE_PRG) {
pr_err("%s: Card stuck in programming state! %s\n",
mmc_hostname(host), __func__);
err = -ETIMEDOUT;
goto out;
}
+
} while (R1_CURRENT_STATE(status) == R1_STATE_PRG);
err = mmc_switch_status_error(host, status);
--
1.8.1.1.dirty
On 27 November 2015 at 02:41, Chaotian Jing <[email protected]> wrote:
> there is a time window between __mmc_send_status() and time_afer(),
> on some eMMC chip, the timeout_ms is only 10ms, if this thread was
> scheduled out during this period, then, even card has already changes
> to transfer state by the result of CMD13, this part of code also treat
> it to timeout error.
> So, need calculate timeout first, then call __mmc_send_status(), if
> already timeout and card still in programing state, then treat it to
> the real timeout error.
>
> Signed-off-by: Chaotian Jing <[email protected]>
> ---
> drivers/mmc/core/mmc_ops.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
> index 1f44426..371aa4b 100644
> --- a/drivers/mmc/core/mmc_ops.c
> +++ b/drivers/mmc/core/mmc_ops.c
> @@ -489,6 +489,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
> unsigned long timeout;
> u32 status = 0;
> bool use_r1b_resp = use_busy_signal;
> + bool expired = false;
>
> mmc_retune_hold(host);
>
> @@ -544,6 +545,12 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
> /* Must check status to be sure of no errors. */
> timeout = jiffies + msecs_to_jiffies(timeout_ms);
> do {
> + /*
> + * Due to the possibility of being preempted after sending the
> + * status command, check the expiration time first.
> + */
> + expired = time_after(jiffies, timeout);
The update of "expired" should have remained within the "if (send_status) {"
Please change that.
I realize that the entire __mmc_switch() function deserves a round of
re-factoring, as it's just too complicated to understand all what goes
on in here. That's another task though. :-)
> +
> if (send_status) {
> err = __mmc_send_status(card, &status, ignore_crc);
> if (err)
> @@ -565,12 +572,13 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
> }
>
> /* Timeout if the device never leaves the program state. */
> - if (time_after(jiffies, timeout)) {
> + if (expired && R1_CURRENT_STATE(status) == R1_STATE_PRG) {
> pr_err("%s: Card stuck in programming state! %s\n",
> mmc_hostname(host), __func__);
> err = -ETIMEDOUT;
> goto out;
> }
> +
> } while (R1_CURRENT_STATE(status) == R1_STATE_PRG);
>
> err = mmc_switch_status_error(host, status);
> --
> 1.8.1.1.dirty
>
Kind regards
Uffe