Re: [PATCH 05/23] arm64: zynqmp: Add L2 cache nodes

Laurent Pinchart
2023-05-10T11:34:24Z

Hi Michal,

On Wed, May 10, 2023 at 09:15:30AM +0200, Michal Simek wrote:
> On 5/10/23 08:57, Laurent Pinchart wrote:
> > On Tue, May 02, 2023 at 03:35:33PM +0200, Michal Simek wrote:
> >> From: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
> >>
> >> Linux kernel throws "cacheinfo: Unable to detect cache hierarchy for
> >> CPU 0" warning when booting on zu+ Soc. To fix it add the L2 cache
> >> node and let each CPU point to it.
> >
> > The commit message should focus on how this change brings the DT in line
> > with the hardware, not on what the Linux kernel does.
>
> ok.
>
> >> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
> >> Signed-off-by: Michal Simek <michal.simek@amd.com>
> >> ---
> >>
> >> arch/arm64/boot/dts/xilinx/zynqmp.dtsi | 9 +++++++++
> >> 1 file changed, 9 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> index bb0d0be30aa0..c2d80c7967e9 100644
> >> --- a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> +++ b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> @@ -33,6 +33,7 @@ cpu0: cpu@0 {
> >> operating-points-v2 = <&cpu_opp_table>;
> >> reg = <0x0>;
> >> cpu-idle-states = <&CPU_SLEEP_0>;
> >> + next-level-cache = <&L2>;
> >> };
> >>
> >> cpu1: cpu@1 {
> >> @@ -42,6 +43,7 @@ cpu1: cpu@1 {
> >> reg = <0x1>;
> >> operating-points-v2 = <&cpu_opp_table>;
> >> cpu-idle-states = <&CPU_SLEEP_0>;
> >> + next-level-cache = <&L2>;
> >> };
> >>
> >> cpu2: cpu@2 {
> >> @@ -51,6 +53,7 @@ cpu2: cpu@2 {
> >> reg = <0x2>;
> >> operating-points-v2 = <&cpu_opp_table>;
> >> cpu-idle-states = <&CPU_SLEEP_0>;
> >> + next-level-cache = <&L2>;
> >> };
> >>
> >> cpu3: cpu@3 {
> >> @@ -60,6 +63,12 @@ cpu3: cpu@3 {
> >> reg = <0x3>;
> >> operating-points-v2 = <&cpu_opp_table>;
> >> cpu-idle-states = <&CPU_SLEEP_0>;
> >> + next-level-cache = <&L2>;
> >> + };
> >> +
> >> + L2: l2-cache {
> >
> > Shouldn't labels be lower-case ?
>
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:220: L2_0:
> l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:241:
> L2_100: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:257:
> L2_200: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:273:
> L2_300: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:289:
> L2_400: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:305:
> L2_500: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:321:
> L2_600: l2-cache {
> Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.yaml:337:
> L2_700: l2-cache {
> Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml:116:
> L2_0: l2-cache {
> Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml:151:
> L2_1: l2-cache {
> Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml:77:
> L2_0: l2-cache {
>
> And in dt spec - 6.2 chapter uppercase letter is valid chars for DTS labels.

Thanks for the clarification. It's all good.

--
Regards,

Laurent Pinchart