[PATCH] mmc: dw_mmc: rockchip: Add DW_MCI_QUIRK_RETRY_DELAY

[Doug Anderson]

Hi,

On Tue, Jan 13, 2015 at 9:51 AM, Doug Anderson <dianders at chromium.org> wrote:
> We've seen at least one card that can get confused during all the
> errors generated during tuning on rk3288.  These errors seem to go
> away with DW_MCI_QUIRK_RETRY_DELAY.  That quirk is documented to be
> for 2.11a and on rk3288 I believe we have 2.70a, but it seems to be
> the same type of problem.
>
> Specifically it looks like in certain error conditions (I saw this
> with Response CRC errors) that data keeps showing up in the FIFO even
> after the error is reported and the CD (command done) bit is set.  If
> we don't wait for this data to finish transferring then it confuses
> the next transaction.  In the specific failure case I ran into I found
> that I could monitor the data_state_mc_busy bit and wait for it to
> clear, but in other failure cases this bit was stuck at busy when we
> saw an error.  Hence a generic big delay seems like the only option.
>
> I have seen this on rk3288, but adding it as a quirk for all Rockchip
> IP for now since most previous quirks have shown up on older IP as
> well.
>
> Signed-off-by: Doug Anderson <dianders at chromium.org>
> ---
> NOTES:
> * This is based atop Addy's patch (mmc: dw_mmc: add quirk for broken
> data transfer over scheme) at
> <https://patchwork.kernel.org/patch/5565431/>, but it would be trivial
> to apply this patch without that one if that were desirable.
> * If someone has a better solution to this problem, I'm all ears.
>
>  drivers/mmc/host/dw_mmc-rockchip.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
> index ba92ebd..b4caf1a 100644
> --- a/drivers/mmc/host/dw_mmc-rockchip.c
> +++ b/drivers/mmc/host/dw_mmc-rockchip.c
> @@ -74,7 +74,8 @@ static int dw_mci_rockchip_init(struct dw_mci *host)
>         host->sdio_id0 = 8;
>
>         /* It needs this quirk on all Rockchip SoCs */
> -       host->pdata->quirks |= DW_MCI_QUIRK_BROKEN_DTO;
> +       host->pdata->quirks |= DW_MCI_QUIRK_BROKEN_DTO |
> +               DW_MCI_QUIRK_RETRY_DELAY;
>
>         return 0;
>  }

All of my recent testing shows that with all of the other fixes Addy
and I have posted recently that this one is no longer needed.  I think
it can be considered Abandoned.

-Doug