Re: [PATCH v5 00/10] clk: implement clock rate protection mechanism

From: Jerome Brunet
Date: Mon Jan 29 2018 - 04:23:09 EST


On Thu, 2017-12-21 at 18:15 -0800, Stephen Boyd wrote:
> On 12/19, Michael Turquette wrote:
> > Quoting Jerome Brunet (2017-12-01 13:51:50)
> > > This Patchset is related the RFC [0] and the discussion around
> > > CLK_SET_RATE_GATE available here [1]
> > >
> > > This patchset introduce clock protection to the CCF core. This can then
> > > be used for:
> > >
> > > * Provide a way for a consumer to claim exclusivity over the rate control
> > > of a provider. Some clock consumers require that a clock rate must not
> > > deviate from its selected frequency. There can be several reasons for
> > > this, not least of which is that some hardware may not be able to
> > > handle or recover from a glitch caused by changing the clock rate while
> > > the hardware is in operation. For such HW, The ability to get exclusive
> > > control of a clock's rate, and release that exclusivity, could be seen
> > > as a fundamental clock rate control primitive. The exclusivity is not
> > > preemptible, so when claimed more than once, is rate is effectively
> > > locked.
> > >
> > > * Provide a similar functionality to providers themselves, fixing
> > > CLK_SET_RATE_GATE flag (enforce clock gating along the tree). While
> > > there might still be a few platforms relying the broken implementation,
> > > tests done has shown this change to be pretty safe.
> >
> > Applied to clk-protect-rate, with the exception that I did not apply
> > "clk: fix CLK_SET_RATE_GATE with clock rate protection" as it breaks
> > qcom clk code.
> >
> > Stephen, do you plan to fix up the qcom clock code so that the
> > SET_RATE_GATE improvement can go in?
> >
>
> I started working on it a while back. Let's see if I can finish
> it off this weekend.
>

Hi Stephen,

Have you been able find something to fix the qcom code regarding this issue ?

Cheers
Jerome