Re: QUIRK_FORCE_HISPD (was: Re: Ricoh R5C822 and QUIRK_FORCE_DMA)

From: Tobias Diedrich
Date: Sat Aug 01 2009 - 01:17:30 EST


Pierre Ossman wrote:
> > On a related note, I had a little time to play a bit more with my
> > R5C822 and found that I can also force-enable HISPD mode, which
> > boost performance further.
> >
>
> This seems odd. What frequency is the controller reporting?
>
> It could be that they originally wanted the controller to be
> high-speed, but that they had stability problems and turned it off.
> There is at least one other controller that went through that scenario.

I assume thats host->max_clk?
The controller seems to report 33MHz for that value.

[130484.232213] mmc0: Controller vendor_ver=02 sdhci_ver=00.
[130484.232213] mmc0: Controller caps=018021a1.
[130484.232213] SDHCI_INT_ENABLE: Can toggle bits e1ff01ff
[130484.232213] SDHCI_HOST_CONTROL: Can toggle bits 06
[130484.232213] DMA forced on (host quirk)
[130484.232213] sdhci-pci 0000:04:00.1: Will use DMA mode even though HW doesn't fully claim to support it.
[130484.232213] host->max_clk: 33000000
[130484.232213] HISPD forced on (host quirk)
[130484.232213] Verified that HOST_CONTROL bit SDHCI_CTRL_HISPD can be toggled
[130484.232213] Could not set SDHCI_CTRL_LED to 1!


--
Tobias PGP: http://9ac7e0bc.uguu.de
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