Re: [PATCH v3 24/26] coresight: etm4x: Refactor probing routine

Mathieu Poirier
2020-11-09T20:43:52Z

On Wed, Oct 28, 2020 at 10:09:43PM +0000, Suzuki K Poulose wrote:
> CoreSight ETM with system register access may not have a
> memory mapped i/o access. Refactor the ETM specific probing
> into a common routine to allow reusing the code for such ETMs.
>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Cc: Mike Leach <mike.leach@linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> ---
> .../coresight/coresight-etm4x-core.c | 48 +++++++++++--------
> 1 file changed, 29 insertions(+), 19 deletions(-)

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

>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index dc537b5612eb..25fab5513604 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -1598,14 +1598,11 @@ static void etm4_pm_clear(void)
> }
> }
>
> -static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
> +static int etm4_probe(struct device *dev, void __iomem *base)
> {
> int ret;
> - void __iomem *base;
> - struct device *dev = &adev->dev;
> struct coresight_platform_data *pdata = NULL;
> struct etmv4_drvdata *drvdata;
> - struct resource *res = &adev->res;
> struct coresight_desc desc = { 0 };
> struct etm_init_arg init_arg = { 0 };
>
> @@ -1629,11 +1626,6 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
> if (fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up"))
> drvdata->skip_power_up = true;
>
> - /* Validity for the resource is already checked by the AMBA core */
> - base = devm_ioremap_resource(dev, res);
> - if (IS_ERR(base))
> - return PTR_ERR(base);
> -
> drvdata->base = base;
>
> spin_lock_init(&drvdata->spinlock);
> @@ -1663,7 +1655,7 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
> if (IS_ERR(pdata))
> return PTR_ERR(pdata);
>
> - adev->dev.platform_data = pdata;
> + dev->platform_data = pdata;
>
> desc.type = CORESIGHT_DEV_TYPE_SOURCE;
> desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC;
> @@ -1683,7 +1675,6 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
>
> etmdrvdata[drvdata->cpu] = drvdata;
>
> - pm_runtime_put(&adev->dev);
> dev_info(&drvdata->csdev->dev, "CPU%d: ETM v%d.%d initialized\n",
> drvdata->cpu, ETM_ARCH_MAJOR_VERSION(drvdata->arch),
> ETM_ARCH_MINOR_VERSION(drvdata->arch));
> @@ -1696,6 +1687,25 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
> return 0;
> }
>
> +static int etm4_probe_amba(struct amba_device *adev, const struct amba_id *id)
> +{
> + void __iomem *base;
> + struct device *dev = &adev->dev;
> + struct resource *res = &adev->res;
> + int ret;
> +
> + /* Validity for the resource is already checked by the AMBA core */
> + base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + ret = etm4_probe(dev, base);
> + if (!ret)
> + pm_runtime_put(&adev->dev);
> +
> + return ret;
> +}
> +
> static struct amba_cs_uci_id uci_id_etm4[] = {
> {
> /* ETMv4 UCI data */
> @@ -1712,15 +1722,15 @@ static void __exit clear_etmdrvdata(void *info)
> etmdrvdata[cpu] = NULL;
> }
>
> -static int __exit etm4_remove(struct amba_device *adev)
> +static int __exit etm4_remove_amba(struct amba_device *adev)
> {
> struct etmv4_drvdata *drvdata = dev_get_drvdata(&adev->dev);
>
> etm_perf_symlink(drvdata->csdev, false);
>
> /*
> - * Taking hotplug lock here to avoid racing between etm4_remove and
> - * CPU hotplug call backs.
> + * Taking hotplug lock here to avoid racing between etm4_remove_amba()
> + * and CPU hotplug call backs.
> */
> cpus_read_lock();
> /*
> @@ -1760,14 +1770,14 @@ static const struct amba_id etm4_ids[] = {
>
> MODULE_DEVICE_TABLE(amba, etm4_ids);
>
> -static struct amba_driver etm4x_driver = {
> +static struct amba_driver etm4x_amba_driver = {
> .drv = {
> .name = "coresight-etm4x",
> .owner = THIS_MODULE,
> .suppress_bind_attrs = true,
> },
> - .probe = etm4_probe,
> - .remove = etm4_remove,
> + .probe = etm4_probe_amba,
> + .remove = etm4_remove_amba,
> .id_table = etm4_ids,
> };
>
> @@ -1781,7 +1791,7 @@ static int __init etm4x_init(void)
> if (ret)
> return ret;
>
> - ret = amba_driver_register(&etm4x_driver);
> + ret = amba_driver_register(&etm4x_amba_driver);
> if (ret) {
> pr_err("Error registering etm4x driver\n");
> etm4_pm_clear();
> @@ -1792,7 +1802,7 @@ static int __init etm4x_init(void)
>
> static void __exit etm4x_exit(void)
> {
> - amba_driver_unregister(&etm4x_driver);
> + amba_driver_unregister(&etm4x_amba_driver);
> etm4_pm_clear();
> }
>
> --
> 2.24.1
>