Re: [PATCH] mmc: rpmb: do not force a retune before RPMB switch

Jorge Ramirez-Ortiz, Foundries
2023-12-05T16:10:12Z

On 04/12/23 19:14:01, Jorge Ramirez-Ortiz, Foundries wrote:
> On 04/12/23 17:58:45, Avri Altman wrote:
> > >
> > > Requesting a retune before switching to the RPMB partition has been
> > > observed to cause CRC errors on the RPMB reads (-EILSEQ).
> > >
> > > Since RPMB reads can not be retried, the clients would be directly affected by
> > > the errors.
> > >
> > > This commit disables the request prior to RPMB switching while allowing the
> > > pause interface to still request a retune before the pause for other use cases.
> > >
> > > This was verified with the sdhci-of-arasan driver (ZynqMP) configured for
> > > HS200 using two separate eMMC cards (DG4064 and 064GB2). In both cases,
> > > the error was easy to reproduce triggering every few tenths of reads.
> > >
> > > Signed-off-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
> > > ---
> > > drivers/mmc/core/block.c | 2 +-
> > > drivers/mmc/core/host.c | 7 ++++---
> > > drivers/mmc/core/host.h | 2 +-
> > > 3 files changed, 6 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index
> > > f9a5cffa64b1..1d69078ad9b2 100644
> > > --- a/drivers/mmc/core/block.c
> > > +++ b/drivers/mmc/core/block.c
> > > @@ -859,7 +859,7 @@ static int mmc_blk_part_switch_pre(struct mmc_card
> > > *card,
> > > if (ret)
> > > return ret;
> > > }
> > > - mmc_retune_pause(card->host);
> > > + mmc_retune_pause(card->host, false);
> > > }
> > >
> > > return ret;
> > > diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index
> > > 096093f7be00..a9b95aaa2235 100644
> > > --- a/drivers/mmc/core/host.c
> > > +++ b/drivers/mmc/core/host.c
> > > @@ -119,13 +119,14 @@ void mmc_retune_enable(struct mmc_host *host)
> > >
> > > /*
> > > * Pause re-tuning for a small set of operations. The pause begins after the
> > > - * next command and after first doing re-tuning.
> > > + * next command and, if retune is set, after first doing re-tuning.
> > > */
> > > -void mmc_retune_pause(struct mmc_host *host)
> > > +void mmc_retune_pause(struct mmc_host *host, bool retune)
> > > {
> > Since mmc_blk_part_switch_pre is the only caller of mmc_retune_pause,
> > How about just move those lines into it?
>
> +1 from me
>
> I wasnt sure if there was some other plan for mmc_retune_pause in the
> future hence why I didnt remove it and extended it instead.
>
> Should I wait for Adrian's confirmation or just go ahead?.

just making sure this is not falling through the cracks.