[PATCH v2] ARM: OMAP3: hwmod data: disable multiblock reads on MMC1/2 on OMAP34xx/35xx <= ES2.1

Steve Sakoman sakoman at gmail.com
Fri Dec 16 11:52:16 EST 2011

On Fri, Dec 16, 2011 at 12:04 AM, Paul Walmsley <paul at pwsan.com> wrote:
> The HSMMC1/HSMMC2 host controllers on OMAP34xx and
> OMAP3503/3515/3525/3530 chips at ES levels prior to 3.0 can't do multiple
> block reads[1].  Mark the hwmod data appropriately.
> Reported by Dave Hylands <dhylands at gmail.com> and Steve Sakoman
> <sakoman at gmail.com>.  Thanks to Steve Sakoman for further help
> testing this patch.
> 1. See for example Advisory "MMC: Multiple Block Read
>   Operation Issue" in _OMAP3530/3525/3515/3503 Silicon Errata_
>   Revision F (October 2010) (SPRZ278F), available from
>   http://focus.ti.com/lit/er/sprz278f/sprz278f.pdf
> Signed-off-by: Paul Walmsley <paul at pwsan.com>
> Cc: Dave Hylands <dhylands at gmail.com>
> Cc: Steve Sakoman <sakoman at gmail.com>
> ---
> The first version of this patch caused MMC hwmods to not be registered on
> 36xx/37xx chips.  Thanks to Steve Sakoman for noting this.  This version
> fixes it - tested on 37xx BeagleBoard.

I tested this on multiple different processor versions:

OMAP3503-GP ES2.1
OMAP3503-GP ES3.1
OMAP3530-GP ES3.1
OMAP3730-GP ES1.0
OMAP3730-GP ES1.2

All worked as expected, multi-block reads were enabled for all except
OMAP3503-GP ES2.1, which displayed:

omap_hsmmc omap_hsmmc.0: multiblock reads disabled due to 35xx erratum; MMC read performance may suffer

Thanks, Paul!

Tested-by: Steve Sakoman <steve at sakoman.com>

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