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

[Xu Yang]

Hi Krzysztof,

> 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...
> 

Because the ddr pmu region is a subset of ddr controller region. When
edac driver is enabled, it will map the whole region firstly. I will check
if this can be changed.

> > Signed-off-by: Ye Li <ye.li at nxp.com>
> > Signed-off-by: Xu Yang <xu.yang_2 at 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

Thanks,
Xu Yang