| Message ID | 1547808474-19427-3-git-send-email-uli+renesas@fpond.eu (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
| Series | H3/M3-W cpuidle support | expand |
On Fri, Jul 26, 2019 at 11:13:29AM +0200, Rosca, Eugeniu (ADITG/ESM1) wrote: [..] > The culprit BSP commits are: > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=3c3b44c752c4ee > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=902ff7caa32dc71c > > Further narrowing it down, it turns out the CA57 cpuidle support is > not responsible for generating the issue. It's all about the CA53 idle > enablement. The reference target is H3-ES2.0-Salvator-X (the problem > originally emerged on M3-based customer HW). [..] Small amendment to the above (based on vanilla testing): Version Issue reproduced? (H3-ES2.0-Salvator-X) v5.3-rc1-96-g6789f873ed37 No v5.3-rc1-96-g6789f873ed37 + [1] No v5.3-rc1-96-g6789f873ed37 + [2] No v5.3-rc1-96-g6789f873ed37 + [1] + [2] Yes [1] https://patchwork.kernel.org/patch/10769701/ ("[v2,1/5] arm64: dts: r8a7795: Add cpuidle support for CA57 cores") [2] https://patchwork.kernel.org/patch/10769689/ ("[v2,2/5] arm64: dts: r8a7795: Add cpuidle support for CA53 cores")
Hi Eugniu, CC cpuidle people On Fri, Jul 26, 2019 at 11:47 AM Eugeniu Rosca <erosca@de.adit-jv.com> wrote: > On Fri, Jul 26, 2019 at 11:13:29AM +0200, Rosca, Eugeniu (ADITG/ESM1) wrote: > [..] > > The culprit BSP commits are: > > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=3c3b44c752c4ee > > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=902ff7caa32dc71c > > > > Further narrowing it down, it turns out the CA57 cpuidle support is > > not responsible for generating the issue. It's all about the CA53 idle > > enablement. The reference target is H3-ES2.0-Salvator-X (the problem > > originally emerged on M3-based customer HW). > [..] > > Small amendment to the above (based on vanilla testing): > > Version Issue reproduced? > (H3-ES2.0-Salvator-X) > v5.3-rc1-96-g6789f873ed37 No > v5.3-rc1-96-g6789f873ed37 + [1] No > v5.3-rc1-96-g6789f873ed37 + [2] No > v5.3-rc1-96-g6789f873ed37 + [1] + [2] Yes > > [1] https://patchwork.kernel.org/patch/10769701/ > ("[v2,1/5] arm64: dts: r8a7795: Add cpuidle support for CA57 cores") > > [2] https://patchwork.kernel.org/patch/10769689/ > ("[v2,2/5] arm64: dts: r8a7795: Add cpuidle support for CA53 cores") Thanks for your report and investigation! Unfortunately your original report didn't make it to lore.kernel.org, and probably also not to the list, due to the large audio attachment. For the newly CCed people, the issue is about consistent dropouts during audio playback using an in-house application, introduced by adding cpuidle support to _both_ the big and LITTLE cores. Thanks! Gr{oetje,eeting}s, Geert
On Mon, Jul 29, 2019 at 09:44:52AM +0200, Geert Uytterhoeven wrote: > Hi Eugniu, > > CC cpuidle people > > On Fri, Jul 26, 2019 at 11:47 AM Eugeniu Rosca <erosca@de.adit-jv.com> wrote: > > On Fri, Jul 26, 2019 at 11:13:29AM +0200, Rosca, Eugeniu (ADITG/ESM1) wrote: > > [..] > > > The culprit BSP commits are: > > > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=3c3b44c752c4ee > > > https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=902ff7caa32dc71c > > > > > > Further narrowing it down, it turns out the CA57 cpuidle support is > > > not responsible for generating the issue. It's all about the CA53 idle > > > enablement. The reference target is H3-ES2.0-Salvator-X (the problem > > > originally emerged on M3-based customer HW). > > [..] > > > > Small amendment to the above (based on vanilla testing): > > > > Version Issue reproduced? > > (H3-ES2.0-Salvator-X) > > v5.3-rc1-96-g6789f873ed37 No > > v5.3-rc1-96-g6789f873ed37 + [1] No > > v5.3-rc1-96-g6789f873ed37 + [2] No > > v5.3-rc1-96-g6789f873ed37 + [1] + [2] Yes > > > > [1] https://patchwork.kernel.org/patch/10769701/ > > ("[v2,1/5] arm64: dts: r8a7795: Add cpuidle support for CA57 cores") > > > > [2] https://patchwork.kernel.org/patch/10769689/ > > ("[v2,2/5] arm64: dts: r8a7795: Add cpuidle support for CA53 cores") > > Thanks for your report and investigation! > > Unfortunately your original report didn't make it to lore.kernel.org, and > probably also not to the list, due to the large audio attachment. > > For the newly CCed people, the issue is about consistent dropouts > during audio playback using an in-house application, introduced by > adding cpuidle support to _both_ the big and LITTLE cores. CPUidle entry/exit latencies are certainly bringing the issue about, I am not an audio expert but I suspect buffering should be tuned to cope with those _increased_ latencies or possibly idle states disabled for certain specific use cases - there is no silver bullet, entering deep idle states will increase latencies, there is no way around it. I am happy to help you debug the issue further. Lorenzo
Hello Geert, hello Lorenzo, Many thanks for your comments and for the willingness to help. For your information, we've recently discovered that, with all the findings already described being absolutely valid for the reference targets, disabling CPUidle on the customer HW is apparently not enough to fix the audio dropouts. We will first try to identify those differences (both HW and SW) which keep the issue reproducible on the customer boards. Once this is hopefully understood, we'll come back with feedback. This investigation also happens to overlap with my vacation. Hence I plan to update you on this topic in 2-4 weeks from now. Thanks again. Best regards, Eugeniu.
On Fri, Jan 18, 2019 at 11:48 AM Ulrich Hecht <uli+renesas@fpond.eu> wrote: > From: Dien Pham <dien.pham.ry@renesas.com> > > Enables cpuidle (core shutdown) support for R-Car H3 CA53 cores. > > Signed-off-by: Dien Pham <dien.pham.ry@renesas.com> > Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com> > Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Gr{oetje,eeting}s, Geert
diff --git a/arch/arm64/boot/dts/renesas/r8a7795.dtsi b/arch/arm64/boot/dts/renesas/r8a7795.dtsi index 7ae974d..483ba3b 100644 --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi @@ -211,6 +211,7 @@ power-domains = <&sysc R8A7795_PD_CA53_CPU0>; next-level-cache = <&L2_CA53>; enable-method = "psci"; + cpu-idle-states = <&CPU_SLEEP_1>; clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>; operating-points-v2 = <&cluster1_opp>; capacity-dmips-mhz = <535>; @@ -223,6 +224,7 @@ power-domains = <&sysc R8A7795_PD_CA53_CPU1>; next-level-cache = <&L2_CA53>; enable-method = "psci"; + cpu-idle-states = <&CPU_SLEEP_1>; clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>; operating-points-v2 = <&cluster1_opp>; capacity-dmips-mhz = <535>; @@ -235,6 +237,7 @@ power-domains = <&sysc R8A7795_PD_CA53_CPU2>; next-level-cache = <&L2_CA53>; enable-method = "psci"; + cpu-idle-states = <&CPU_SLEEP_1>; clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>; operating-points-v2 = <&cluster1_opp>; capacity-dmips-mhz = <535>; @@ -247,6 +250,7 @@ power-domains = <&sysc R8A7795_PD_CA53_CPU3>; next-level-cache = <&L2_CA53>; enable-method = "psci"; + cpu-idle-states = <&CPU_SLEEP_1>; clocks = <&cpg CPG_CORE R8A7795_CLK_Z2>; operating-points-v2 = <&cluster1_opp>; capacity-dmips-mhz = <535>; @@ -277,6 +281,15 @@ exit-latency-us = <500>; min-residency-us = <4000>; }; + + CPU_SLEEP_1: cpu-sleep-1 { + compatible = "arm,idle-state"; + arm,psci-suspend-param = <0x0010000>; + local-timer-stop; + entry-latency-us = <700>; + exit-latency-us = <700>; + min-residency-us = <5000>; + }; }; };