Re: [PATCH v3 08/26] coresight: tpiu: Prepare for using coresight device access abstraction

Mathieu Poirier
2020-11-03T18:04:03Z

On Wed, Oct 28, 2020 at 10:09:27PM +0000, Suzuki K Poulose wrote:
> Prepare the TPIU driver to make use of the CoreSight device access
> abstraction layer. The driver touches the device even before the
> coresight device is registered. Thus we could be accessing the
> devices without a csdev. As we are about to use the abstraction
> layer for accessing the device, pass in the access directly
> to avoid having to deal with the un-initialised csdev.
>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Cc: Mike Leach <mike.leach@linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> ---
> drivers/hwtracing/coresight/coresight-tpiu.c | 30 +++++++++-----------
> 1 file changed, 13 insertions(+), 17 deletions(-)

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>

>
> diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
> index dfa3b91d0281..98c4a029854c 100644
> --- a/drivers/hwtracing/coresight/coresight-tpiu.c
> +++ b/drivers/hwtracing/coresight/coresight-tpiu.c
> @@ -60,49 +60,45 @@ struct tpiu_drvdata {
> struct coresight_device *csdev;
> };
>
> -static void tpiu_enable_hw(struct tpiu_drvdata *drvdata)
> +static void tpiu_enable_hw(struct csdev_access *csa)
> {
> - CS_UNLOCK(drvdata->base);
> + CS_UNLOCK(csa->base);
>
> /* TODO: fill this up */
>
> - CS_LOCK(drvdata->base);
> + CS_LOCK(csa->base);
> }
>
> static int tpiu_enable(struct coresight_device *csdev, u32 mode, void *__unused)
> {
> - struct tpiu_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> -
> - tpiu_enable_hw(drvdata);
> + tpiu_enable_hw(&csdev->access);
> atomic_inc(csdev->refcnt);
> dev_dbg(&csdev->dev, "TPIU enabled\n");
> return 0;
> }
>
> -static void tpiu_disable_hw(struct tpiu_drvdata *drvdata)
> +static void tpiu_disable_hw(struct csdev_access *csa)
> {
> - CS_UNLOCK(drvdata->base);
> + CS_UNLOCK(csa->base);
>
> /* Clear formatter and stop on flush */
> - writel_relaxed(FFCR_STOP_FI, drvdata->base + TPIU_FFCR);
> + csdev_access_relaxed_write32(csa, FFCR_STOP_FI, TPIU_FFCR);
> /* Generate manual flush */
> - writel_relaxed(FFCR_STOP_FI | FFCR_FON_MAN, drvdata->base + TPIU_FFCR);
> + csdev_access_relaxed_write32(csa, FFCR_STOP_FI | FFCR_FON_MAN, TPIU_FFCR);
> /* Wait for flush to complete */
> - coresight_timeout(drvdata->base, TPIU_FFCR, FFCR_FON_MAN_BIT, 0);
> + coresight_timeout(csa->base, TPIU_FFCR, FFCR_FON_MAN_BIT, 0);
> /* Wait for formatter to stop */
> - coresight_timeout(drvdata->base, TPIU_FFSR, FFSR_FT_STOPPED_BIT, 1);
> + coresight_timeout(csa->base, TPIU_FFSR, FFSR_FT_STOPPED_BIT, 1);
>
> - CS_LOCK(drvdata->base);
> + CS_LOCK(csa->base);
> }
>
> static int tpiu_disable(struct coresight_device *csdev)
> {
> - struct tpiu_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> -
> if (atomic_dec_return(csdev->refcnt))
> return -EBUSY;
>
> - tpiu_disable_hw(drvdata);
> + tpiu_disable_hw(&csdev->access);
>
> dev_dbg(&csdev->dev, "TPIU disabled\n");
> return 0;
> @@ -152,7 +148,7 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
> desc.access = CSDEV_ACCESS_IOMEM(base);
>
> /* Disable tpiu to support older devices */
> - tpiu_disable_hw(drvdata);
> + tpiu_disable_hw(&desc.access);
>
> pdata = coresight_get_platform_data(dev);
> if (IS_ERR(pdata))
> --
> 2.24.1
>