Re: [PATCH 1/2] perf: imx9_ddr_perf: resolve resource map conflict

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 14/09/2023 12:20, Xu Yang wrote:
> Usually, the ddr pmu node will be a subnode of DDR controller, then using
> devm_platform_ioremap_resource will report conflict with DDR controller
> resource. So update the driver to use devm_ioremap to avoid such
> resource check.
> 

Why would you like to map same region twice? The resource check is for
purpose there...

> Signed-off-by: Ye Li <ye.li@nxp.com>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> ---
>  drivers/perf/fsl_imx9_ddr_perf.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/perf/fsl_imx9_ddr_perf.c b/drivers/perf/fsl_imx9_ddr_perf.c
> index 5cf770a1bc31..885024665968 100644
> --- a/drivers/perf/fsl_imx9_ddr_perf.c
> +++ b/drivers/perf/fsl_imx9_ddr_perf.c
> @@ -602,8 +602,15 @@ static int ddr_perf_probe(struct platform_device *pdev)
>  	void __iomem *base;
>  	int ret, irq;
>  	char *name;
> +	struct resource *r;
>  
> -	base = devm_platform_ioremap_resource(pdev, 0);
> +	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!r) {
> +		dev_err(&pdev->dev, "platform_get_resource() failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	base = devm_ioremap(&pdev->dev, r->start, resource_size(r));

You need to document this, otherwise someone will revert your commit soon.


Best regards,
Krzysztof