Re: [PATCH v3 10/26] coresight: Convert claim/disclaim operations to use access wrappers

[Suzuki K Poulose]

On 11/3/20 6:36 PM, Mathieu Poirier wrote:
> On Wed, Oct 28, 2020 at 10:09:29PM +0000, Suzuki K Poulose wrote:
> > Convert the generic CLAIM tag management APIs to use the
> > device access layer abstraction.
> >
> > Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > Cc: Mike Leach <mike.leach@xxxxxxxxxx>
> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > ---
> >   drivers/hwtracing/coresight/coresight-catu.c  |  6 +-
> >   drivers/hwtracing/coresight/coresight-core.c  | 66 +++++++++++--------
> >   .../hwtracing/coresight/coresight-cti-core.c  | 17 +++--
> >   drivers/hwtracing/coresight/coresight-etb10.c |  4 +-
> >   .../coresight/coresight-etm3x-core.c          |  8 ++-
> >   .../coresight/coresight-etm4x-core.c          |  4 +-
> >   .../hwtracing/coresight/coresight-funnel.c    |  6 +-
> >   .../coresight/coresight-replicator.c          | 16 +++--
> >   .../hwtracing/coresight/coresight-tmc-etf.c   | 10 +--
> >   .../hwtracing/coresight/coresight-tmc-etr.c   |  4 +-
> >   include/linux/coresight.h                     | 16 ++---
> >   11 files changed, 95 insertions(+), 62 deletions(-)

> >   }
> >   
> > -static inline void coresight_set_claim_tags(void __iomem *base)
> > +static inline void coresight_set_claim_tags(struct coresight_device *csdev)
> >   {
> > -	writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMSET);
> > +	csdev_access_relaxed_write32(&csdev->access, CORESIGHT_CLAIM_SELF_HOSTED,
> > +				  CORESIGHT_CLAIMSET);
>
> Indentation
>
> >   	isb();
> >   }
> >   
> > -static inline void coresight_clear_claim_tags(void __iomem *base)
> > +static inline void coresight_clear_claim_tags(struct coresight_device *csdev)
> >   {
> > -	writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMCLR);
> > +	csdev_access_relaxed_write32(&csdev->access, CORESIGHT_CLAIM_SELF_HOSTED,
> > +				  CORESIGHT_CLAIMCLR);
>
> Indentation
>
> >   	isb();
> >   }
> >   


> > diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
> > index fcf25740116c..e35d79e74e30 100644
> > --- a/drivers/hwtracing/coresight/coresight-replicator.c
> > +++ b/drivers/hwtracing/coresight/coresight-replicator.c
> > @@ -45,12 +45,18 @@ struct replicator_drvdata {
> >   
> >   static void dynamic_replicator_reset(struct replicator_drvdata *drvdata)
> >   {
> > +	struct coresight_device *csdev = drvdata->csdev;
> >   	CS_UNLOCK(drvdata->base);
> >   
> > -	if (!coresight_claim_device_unlocked(drvdata->base)) {
> > +	if (WARN_ON(!csdev))
> > +		return;
>
> I don't see a need for this check. Function replicator_reset() is called from
> probe() where the validity of drvdata->csdev is checked just before.

Correct. We only needed drvdata->base earlier, which was fine. But we
now need csdev for the reset. That check was added to make sure that
we don't break the guarantee. I could take that down.

Cheers
Suzuki