| Message ID | 1448898998-32749-1-git-send-email-grygorii.strashko@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Grygorii Strashko <grygorii.strashko@ti.com> [151130 07:58]: > ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. > But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. > Timekeeping core misbehaves. For example, execution of command > "sleep 5" will take 10 sec instead of 5. > > Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use > it for clocking ARM TWD and Global timer (same way as on OMAP4). > > Cc: Tony Lindgren <tony@atomide.com> > Cc: Felipe Balbi <balbi@ti.com> > Cc: Tero Kristo <t-kristo@ti.com> > Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Is this fix alone enough or do you still need to disable other the ARM timers in the board specific dts file? Regards, Tony > --- > Changes in v2: > - fix: mpu_periphclk should be clocked from dpll_mpu_m2_ck instead of > dpll_mpu_ck. > link on v1: > http://www.spinics.net/lists/arm-kernel/msg463898.html > > arch/arm/boot/dts/am4372.dtsi | 4 ++-- > arch/arm/boot/dts/am43xx-clocks.dtsi | 8 ++++++++ > 2 files changed, 10 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/boot/dts/am4372.dtsi b/arch/arm/boot/dts/am4372.dtsi > index d83ff9c..de8791a 100644 > --- a/arch/arm/boot/dts/am4372.dtsi > +++ b/arch/arm/boot/dts/am4372.dtsi > @@ -74,7 +74,7 @@ > reg = <0x48240200 0x100>; > interrupts = <GIC_PPI 11 IRQ_TYPE_LEVEL_HIGH>; > interrupt-parent = <&gic>; > - clocks = <&dpll_mpu_m2_ck>; > + clocks = <&mpu_periphclk>; > }; > > local_timer: timer@48240600 { > @@ -82,7 +82,7 @@ > reg = <0x48240600 0x100>; > interrupts = <GIC_PPI 13 IRQ_TYPE_LEVEL_HIGH>; > interrupt-parent = <&gic>; > - clocks = <&dpll_mpu_m2_ck>; > + clocks = <&mpu_periphclk>; > }; > > l2-cache-controller@48242000 { > diff --git a/arch/arm/boot/dts/am43xx-clocks.dtsi b/arch/arm/boot/dts/am43xx-clocks.dtsi > index cc88728..a38af2b 100644 > --- a/arch/arm/boot/dts/am43xx-clocks.dtsi > +++ b/arch/arm/boot/dts/am43xx-clocks.dtsi > @@ -259,6 +259,14 @@ > ti,invert-autoidle-bit; > }; > > + mpu_periphclk: mpu_periphclk { > + #clock-cells = <0>; > + compatible = "fixed-factor-clock"; > + clocks = <&dpll_mpu_m2_ck>; > + clock-mult = <1>; > + clock-div = <2>; > + }; > + > dpll_ddr_ck: dpll_ddr_ck { > #clock-cells = <0>; > compatible = "ti,am3-dpll-clock"; > -- > 2.6.3 >
On 12/03/2015 06:35 PM, Tony Lindgren wrote: > * Grygorii Strashko <grygorii.strashko@ti.com> [151130 07:58]: >> ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. >> But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. >> Timekeeping core misbehaves. For example, execution of command >> "sleep 5" will take 10 sec instead of 5. >> >> Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use >> it for clocking ARM TWD and Global timer (same way as on OMAP4). >> >> Cc: Tony Lindgren <tony@atomide.com> >> Cc: Felipe Balbi <balbi@ti.com> >> Cc: Tero Kristo <t-kristo@ti.com> >> Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") >> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> > > Is this fix alone enough or do you still need to disable other the ARM > timers in the board specific dts file? > This one is independent and it's required for -rc, because ARM TWD timer will be selected now for am43xx even if http://www.spinics.net/lists/arm-kernel/msg459649.html is not merged yet ;) in case of omap2plus_defconfig build.
Hi Tony, Felipe, Tero, On 12/03/2015 08:04 PM, Grygorii Strashko wrote: > On 12/03/2015 06:35 PM, Tony Lindgren wrote: >> * Grygorii Strashko <grygorii.strashko@ti.com> [151130 07:58]: >>> ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. >>> But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. >>> Timekeeping core misbehaves. For example, execution of command >>> "sleep 5" will take 10 sec instead of 5. >>> >>> Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use >>> it for clocking ARM TWD and Global timer (same way as on OMAP4). >>> >>> Cc: Tony Lindgren <tony@atomide.com> >>> Cc: Felipe Balbi <balbi@ti.com> >>> Cc: Tero Kristo <t-kristo@ti.com> >>> Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") >>> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> >> >> Is this fix alone enough or do you still need to disable other the ARM >> timers in the board specific dts file? >> > > This one is independent and it's required for -rc, because ARM TWD timer will be selected > now for am43xx even if http://www.spinics.net/lists/arm-kernel/msg459649.html > is not merged yet ;) in case of omap2plus_defconfig build. > > Are there any comments objection? Could this patch be merged as part of -rc cycle?
Hi, Grygorii Strashko <grygorii.strashko@ti.com> writes: > ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. > But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. > Timekeeping core misbehaves. For example, execution of command > "sleep 5" will take 10 sec instead of 5. > > Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use > it for clocking ARM TWD and Global timer (same way as on OMAP4). > > Cc: Tony Lindgren <tony@atomide.com> > Cc: Felipe Balbi <balbi@ti.com> > Cc: Tero Kristo <t-kristo@ti.com> > Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> this seems to be the best fix for this problem, yeah. Reviewed-by: Felipe Balbi <balbi@ti.com>
* Felipe Balbi <balbi@ti.com> [151208 10:05]: > > Hi, > > Grygorii Strashko <grygorii.strashko@ti.com> writes: > > ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. > > But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. > > Timekeeping core misbehaves. For example, execution of command > > "sleep 5" will take 10 sec instead of 5. > > > > Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use > > it for clocking ARM TWD and Global timer (same way as on OMAP4). > > > > Cc: Tony Lindgren <tony@atomide.com> > > Cc: Felipe Balbi <balbi@ti.com> > > Cc: Tero Kristo <t-kristo@ti.com> > > Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") > > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> > > this seems to be the best fix for this problem, yeah. > > Reviewed-by: Felipe Balbi <balbi@ti.com> OK applying into omap-for-v4.4/fixes thanks. Tony
diff --git a/arch/arm/boot/dts/am4372.dtsi b/arch/arm/boot/dts/am4372.dtsi index d83ff9c..de8791a 100644 --- a/arch/arm/boot/dts/am4372.dtsi +++ b/arch/arm/boot/dts/am4372.dtsi @@ -74,7 +74,7 @@ reg = <0x48240200 0x100>; interrupts = <GIC_PPI 11 IRQ_TYPE_LEVEL_HIGH>; interrupt-parent = <&gic>; - clocks = <&dpll_mpu_m2_ck>; + clocks = <&mpu_periphclk>; }; local_timer: timer@48240600 { @@ -82,7 +82,7 @@ reg = <0x48240600 0x100>; interrupts = <GIC_PPI 13 IRQ_TYPE_LEVEL_HIGH>; interrupt-parent = <&gic>; - clocks = <&dpll_mpu_m2_ck>; + clocks = <&mpu_periphclk>; }; l2-cache-controller@48242000 { diff --git a/arch/arm/boot/dts/am43xx-clocks.dtsi b/arch/arm/boot/dts/am43xx-clocks.dtsi index cc88728..a38af2b 100644 --- a/arch/arm/boot/dts/am43xx-clocks.dtsi +++ b/arch/arm/boot/dts/am43xx-clocks.dtsi @@ -259,6 +259,14 @@ ti,invert-autoidle-bit; }; + mpu_periphclk: mpu_periphclk { + #clock-cells = <0>; + compatible = "fixed-factor-clock"; + clocks = <&dpll_mpu_m2_ck>; + clock-mult = <1>; + clock-div = <2>; + }; + dpll_ddr_ck: dpll_ddr_ck { #clock-cells = <0>; compatible = "ti,am3-dpll-clock";
ARM TWD and Global timer are clocked by PERIPHCLK which is MPU_CLK/2. But now they are clocked by dpll_mpu_m2_ck == MPU_CLK and, as result. Timekeeping core misbehaves. For example, execution of command "sleep 5" will take 10 sec instead of 5. Hence, fix it by adding mpu_periphclk ("fixed-factor-clock") and use it for clocking ARM TWD and Global timer (same way as on OMAP4). Cc: Tony Lindgren <tony@atomide.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Tero Kristo <t-kristo@ti.com> Fixes:commit 8cbd4c2f6a99 ("arm: boot: dts: am4372: add ARM timers and SCU nodes") Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> --- Changes in v2: - fix: mpu_periphclk should be clocked from dpll_mpu_m2_ck instead of dpll_mpu_ck. link on v1: http://www.spinics.net/lists/arm-kernel/msg463898.html arch/arm/boot/dts/am4372.dtsi | 4 ++-- arch/arm/boot/dts/am43xx-clocks.dtsi | 8 ++++++++ 2 files changed, 10 insertions(+), 2 deletions(-)