Re: [PATCH] clk: qcom: gcc-sdm845: Use floor ops for sdcc clks

[Stephen Boyd]

Quoting Taniya Das (2019-09-03 08:52:12)
> Hi,
> 
> On 8/31/2019 3:04 AM, Doug Anderson wrote:
> > Hi,
> > 
> > On Fri, Aug 30, 2019 at 12:51 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
> >>
> >> Some MMC cards fail to enumerate properly when inserted into an MMC slot
> >> on sdm845 devices. This is because the clk ops for qcom clks round the
> >> frequency up to the nearest rate instead of down to the nearest rate.
> >> For example, the MMC driver requests a frequency of 52MHz from
> >> clk_set_rate() but the qcom implementation for these clks rounds 52MHz
> >> up to the next supported frequency of 100MHz. The MMC driver could be
> >> modified to request clk rate ranges but for now we can fix this in the
> >> clk driver by changing the rounding policy for this clk to be round down
> >> instead of round up.
> > 
> > Since all the MMC rates are expressed as "maximum" clock rates doing
> > it like you are doing it now seems sane.
> > 
> > 
> 
> Looks like we need to update/track it for all SDCC clocks for all targets.
> 

Yeah. It would be great if you can send the patches. Otherwise I'll
throw it on my todo list named 'forever'.