[PATCH 1/2] mmc: sdhci-iproc: Apply caps from bcm2835-mmc driver

Stefan Wahren stefan.wahren at i2se.com
Tue Jan 3 12:23:59 PST 2017

Hi Eric,

> Eric Anholt <eric at anholt.net> hat am 3. Januar 2017 um 19:27 geschrieben:
> Stefan Wahren <stefan.wahren at i2se.com> writes:
> > Since the mmc module on bcm2835 neither provide a capabilities register nor 
> > free documentation we must rely on the downstream implementation [1].
> Yeah, caps reg is wired to 0, but it can do high speed.
> Since we're VDD_330 only, I'm not sure the driver type flags do
> anything, but I'm still good with having consistency.

yes, the driver type flags currently have no benefit.

> Reviewed-by: Eric Anholt <eric at anholt.net>
> Interested in porting over the DMA support? :)

AFAIK the sdhci doesn't support external DMA (required for bcm2835).
So DMA support would result in a new driver, which i'm currently not interested.

But i've prepared a fixup patch series for the sdhost driver i want to send to Gerd.

> I also noticed that the emmc wrapper module claims it can run with a
> clock from 50-100mhz, and the arasan says it can run at up to 50, 52, or
> 208mhz depending on SD/MMC mode.  Could we get a boost from running the
> module at a higher clock rate?

Sorry, i can't follow. Do you mean DDR mode?

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