[PATCH 2/2] coresight: etm4x: Fix save and restore of TRCVMIDCCTLR1 register

Suzuki K Poulose suzuki.poulose at arm.com
Mon Sep 28 07:05:57 EDT 2020


Hi Sai,

On 09/27/2020 05:20 PM, Sai Prakash Ranjan wrote:
> In commit f188b5e76aae ("coresight: etm4x: Save/restore state
> across CPU low power states"), mistakenly TRCVMIDCCTLR1 register
> value was saved in trcvmidcctlr0 state variable which is used to
> store TRCVMIDCCTLR0 register value in etm4x_cpu_save() and then
> same value is written back to both TRCVMIDCCTLR0 and TRCVMIDCCTLR1
> in etm4x_cpu_restore(). There is already a trcvmidcctlr1 state
> variable available for TRCVMIDCCTLR1, so use it.
> 
> Fixes: 8b44fdfef6a2 ("coresight: etm4x: Allow etm4x to be built as a module")

Why is this commit in question ?

> Fixes: f188b5e76aae ("coresight: etm4x: Save/restore state across CPU low power states")

I believe this is the right fixes tag.

> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan at codeaurora.org>
> ---
>   drivers/hwtracing/coresight/coresight-etm4x-core.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index de76d57850bc..abd706b216ac 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -1243,7 +1243,7 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
>   	state->trccidcctlr1 = readl(drvdata->base + TRCCIDCCTLR1);
>   
>   	state->trcvmidcctlr0 = readl(drvdata->base + TRCVMIDCCTLR0);
> -	state->trcvmidcctlr0 = readl(drvdata->base + TRCVMIDCCTLR1);
> +	state->trcvmidcctlr1 = readl(drvdata->base + TRCVMIDCCTLR1);
>   
>   	state->trcclaimset = readl(drvdata->base + TRCCLAIMCLR);
>   
> @@ -1353,7 +1353,7 @@ static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
>   	writel_relaxed(state->trccidcctlr1, drvdata->base + TRCCIDCCTLR1);
>   
>   	writel_relaxed(state->trcvmidcctlr0, drvdata->base + TRCVMIDCCTLR0);
> -	writel_relaxed(state->trcvmidcctlr0, drvdata->base + TRCVMIDCCTLR1);
> +	writel_relaxed(state->trcvmidcctlr1, drvdata->base + TRCVMIDCCTLR1);
>   

Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>



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