Re: [PATCH v2 3/4] arm64: dts: sdm845: move bus clock to mdp node for sdm845 target

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Fri 28 May 10:33 CDT 2021, Dmitry Baryshkov wrote:

> On 07/04/2021 18:01, Dmitry Baryshkov wrote:
> > Move the bus clock to mdp device node,in order to facilitate bus band
> > width scaling on sdm845 target.
> > 
> > The parent device MDSS will not vote for bus bw, instead the vote will
> > be triggered by mdp device node. Since a minimum vote is required to
> > turn on bus clock, move the clock node to mdp device from where the
> > votes are requested.
> 
> drm/msm patches were merged through the msm tree (targeting 5.13). Shouldn't
> we also merge these two patches (targeting 5.13 as fixes or 5.14)?
> 

Does the vote for the bus clock result in an improvement or is the
device simply not working without it?

Regards,
Bjorn

> > 
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >   arch/arm64/boot/dts/qcom/sdm845.dtsi | 8 ++++----
> >   1 file changed, 4 insertions(+), 4 deletions(-)
> > 
> > diff --git a/arch/arm64/boot/dts/qcom/sdm845.dtsi b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > index 7395ef20b90e..55704804c2ca 100644
> > --- a/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > @@ -4136,9 +4136,8 @@ mdss: mdss@ae00000 {
> >   			power-domains = <&dispcc MDSS_GDSC>;
> >   			clocks = <&gcc GCC_DISP_AHB_CLK>,
> > -				 <&gcc GCC_DISP_AXI_CLK>,
> >   				 <&dispcc DISP_CC_MDSS_MDP_CLK>;
> > -			clock-names = "iface", "bus", "core";
> > +			clock-names = "iface", "core";
> >   			assigned-clocks = <&dispcc DISP_CC_MDSS_MDP_CLK>;
> >   			assigned-clock-rates = <300000000>;
> > @@ -4166,11 +4165,12 @@ mdss_mdp: mdp@ae01000 {
> >   				      <0 0x0aeb0000 0 0x2008>;
> >   				reg-names = "mdp", "vbif";
> > -				clocks = <&dispcc DISP_CC_MDSS_AHB_CLK>,
> > +				clocks = <&gcc GCC_DISP_AXI_CLK>,
> > +					 <&dispcc DISP_CC_MDSS_AHB_CLK>,
> >   					 <&dispcc DISP_CC_MDSS_AXI_CLK>,
> >   					 <&dispcc DISP_CC_MDSS_MDP_CLK>,
> >   					 <&dispcc DISP_CC_MDSS_VSYNC_CLK>;
> > -				clock-names = "iface", "bus", "core", "vsync";
> > +				clock-names = "gcc-bus", "iface", "bus", "core", "vsync";
> >   				assigned-clocks = <&dispcc DISP_CC_MDSS_MDP_CLK>,
> >   						  <&dispcc DISP_CC_MDSS_VSYNC_CLK>;
> > 
> 
> 
> -- 
> With best wishes
> Dmitry