Re: [PATCH 2/4] clk: qcom: Add clk_rcg2_gfx3d_ops for SDM845

[Amit Nischal]

On 2018-08-03 04:14, Stephen Boyd wrote:
> Quoting Amit Nischal (2018-07-30 04:28:56)
> > On 2018-07-25 12:28, Stephen Boyd wrote:
> > >
> > > Ok. Sounds good! Is the rate range call really needed? It can't be
> > > determined in the PLL code with some table or avoided by making sure
> > > GPU
> > > uses OPP table with only approved frequencies?
> > >
> >
> > Currently fabia PLL code does not have any table to check this and
> > intention
> > was to avoid relying on the client to call set_rate with only approved
> > frequencies so we have added the set_rate_range() call in the GPUCC
> > driver
> > in order to set the rate range.
>
> But GPU will use OPP so it doesn't seem like it really buys us anything
> here. And it really doesn't matter when the clk driver implementation
> doesn't use the min/max to clamp the values of the round_rate() call. 
> Is
> that being done here? I need to double check. I would be more convinced
> if the implementation was looking at min/max to constrain the rate
> requested.

So our understanding is that GPU(client) driver will always call the
set_rate with approved frequencies only and we can completely rely on 
the
client. Is our understanding is correct?

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