On 08-07-19, 08:43, Anson Huang wrote: > Hi, Viresh > > > On 04-07-19, 07:49, Leonard Crestez wrote: > > > On 7/4/2019 9:23 AM, Anson.Huang@xxxxxxx wrote: > > > > From: Anson Huang <Anson.Huang@xxxxxxx> > > > > > > > > Assign highest OPP as suspend OPP to reduce suspend/resume latency > > > > on i.MX8MM. > > > > > > > > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx> > > > > --- > > > > arch/arm64/boot/dts/freescale/imx8mm.dtsi | 1 + > > > > 1 file changed, 1 insertion(+) > > > > > > > > diff --git a/arch/arm64/boot/dts/freescale/imx8mm.dtsi > > > > b/arch/arm64/boot/dts/freescale/imx8mm.dtsi > > > > index b11fc5e..3a62407 100644 > > > > --- a/arch/arm64/boot/dts/freescale/imx8mm.dtsi > > > > +++ b/arch/arm64/boot/dts/freescale/imx8mm.dtsi > > > > @@ -136,6 +136,7 @@ > > > > opp-microvolt = <1000000>; > > > > opp-supported-hw = <0x8>, <0x3>; > > > > clock-latency-ns = <150000>; > > > > + opp-suspend; > > > > }; > > > > }; > > > > > > What if the highest OPP is unavailable due to speed grading? > > > > What does this exactly mean ? How is the OPP made unavailable in your > > case ? > > That is because in i.MX8M series SoCs, the speed grading and market segment > fuses settings could affect the OPP defined in DT, in a word, all possible OPPs > are defined in DT, but each parts could ONLY select some of them to be working > OPPs, so if the "opp-suspend" is added for 1 OPP in DT, if the part's speed grading or > market segment fuse settings make that OPP as unavailable, then that "opp-suspend" > is NOT working at all. How is this selection done ? You using some OPP helper or something else ? -- viresh
