Re: [PATCH 4/4] perf: arm_spe: Enable ACPI/Platform automatic module loading

[Jeremy Linton]

Hi,

On 4/4/19 12:04 PM, Will Deacon wrote:
> On Tue, Mar 26, 2019 at 05:39:38PM -0500, Jeremy Linton wrote:
> > Lets add the MODULE_TABLE and platform id_table entries so that
> > the SPE driver can attach to the ACPI platform device created by
> > the core pmu code.
> >
> > Signed-off-by: Jeremy Linton <jeremy.linton@xxxxxxx>
> > Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> > ---
> >   drivers/perf/arm_spe_pmu.c | 11 +++++++++--
> >   1 file changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
> > index 7cb766dafe85..ffa2c76c08bb 100644
> > --- a/drivers/perf/arm_spe_pmu.c
> > +++ b/drivers/perf/arm_spe_pmu.c
> > @@ -1176,7 +1176,13 @@ static const struct of_device_id arm_spe_pmu_of_match[] = {
> >   };
> >   MODULE_DEVICE_TABLE(of, arm_spe_pmu_of_match);
> >   
> > -static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev)
> > +static const struct platform_device_id arm_spe_match[] = {
> > +	{ "arm,spe-v1", 0},
>
> It would be nice if we could avoid duplicating this string from the ACPI
> parsing code.

Ok sure, I just need to find a good common place for it.

> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(platform, arm_spe_match);
> > +
> > +static int arm_spe_pmu_device_probe(struct platform_device *pdev)
> >   {
> >   	int ret;
> >   	struct arm_spe_pmu *spe_pmu;
> > @@ -1236,11 +1242,12 @@ static int arm_spe_pmu_device_remove(struct platform_device *pdev)
> >   }
> >   
> >   static struct platform_driver arm_spe_pmu_driver = {
> > +	.id_table = arm_spe_match,
> >   	.driver	= {
> >   		.name		= DRVNAME,
> >   		.of_match_table	= of_match_ptr(arm_spe_pmu_of_match),
>
> Hmm, so some other drivers don't hook .id_table like you do, but instead
> hook .acpi_match_table in the driver structure. Is that not better?

This isn't actually an ACPI device, (aka not defined in the namespace), 
so its missing much of the ACPI functionality. I think that also means 
its needs to be declared this way.


> Will