[PATCH] mmc: sdhci-of-arasan: Properly set corecfg_clockmultipler on rk3399

Shawn Lin shawn.lin at rock-chips.com
Fri Aug 26 19:10:40 PDT 2016

On 2016/8/26 23:46, Doug Anderson wrote:
> Hi,
> On Fri, Aug 26, 2016 at 1:31 AM, Heiko Stübner <heiko at sntech.de> wrote:
>> The aclk_emmc_grf is (similar to aclk_vio_grf etc) part of the emmc block.
> Right now aclk_emmc_grf is set as CLK_IGNORE_UNUSED, which is my least
> favorite clock property.  ;)
> Due to the parenting structure and the fact that we just added
> "aclk_emmc_noc" as a critical clock, I believe that this means that
> aclk_emmc_grf will never turn off.  It would be awfully nice if you

It just means we don't gate aclk_emmc_grf/aclk_emmc_noc if not 
referenced, but actually we don't prevent clk driver to gate its parent
which means it isn't really CLK_IGNORE_UNUSED or critical to a certain
degree from my personal view as we may need to propagate this feature
forward to its parents.

Anyway, that seems a bit beyond the topic of what $SUBJECT wanna handle
with. But I agree that we should make this dependency relationship more
exlicit to users anyway.

I will do it once $SUBJECT applied. :)


> could send up a patch to actually turn the "grf" clock on when needed
> and turn it off when not needed.  That would let us remove the
> "CLK_IGNORE_UNUSED" from all of the eMMC clocks in rk3399.
> I noticed you send v2 of your patch series and that looks fine to me.
> The issue with not handling the "grf" clock is not a new one and
> shouldn't block your patch.  ...but it would still be nice to handle
> properly.
> -Doug

Best Regards
Shawn Lin

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