[PATCH V6 08/11] coresight: tpiu: Move ACPI support from AMBA driver to platform driver
Suzuki K Poulose
suzuki.poulose at arm.com
Tue Mar 12 09:37:08 PDT 2024
On 12/03/2024 10:23, Anshuman Khandual wrote:
> Add support for the tpiu device in the platform driver, which can then be
> used on ACPI based platforms. This change would now allow runtime power
> management for ACPI based systems. The driver would try to enable the APB
> clock if available. But first this renames and then refactors tpiu_probe()
> and tpiu_remove(), making sure it can be used both for platform and AMBA
> drivers. This also moves pm_runtime_put() from tpiu_probe() to the callers.
>
> Cc: Lorenzo Pieralisi <lpieralisi at kernel.org>
> Cc: Sudeep Holla <sudeep.holla at arm.com>
> Cc: Suzuki K Poulose <suzuki.poulose at arm.com>
> Cc: Mike Leach <mike.leach at linaro.org>
> Cc: James Clark <james.clark at arm.com>
> Cc: linux-acpi at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: linux-kernel at vger.kernel.org
> Cc: coresight at lists.linaro.org
> Tested-by: Sudeep Holla <sudeep.holla at arm.com> # Boot and driver probe only
> Acked-by: Sudeep Holla <sudeep.holla at arm.com> # For ACPI related changes
> Reviewed-by: James Clark <james.clark at arm.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
> ---
> Changes in V6:
>
> - Added WARN_ON(!drvdata) check in tpiu_platform_remove()
> - Added additional elements for acpi_device_id[]
>
> drivers/acpi/arm64/amba.c | 1 -
> drivers/hwtracing/coresight/coresight-tpiu.c | 103 +++++++++++++++++--
> 2 files changed, 93 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/acpi/arm64/amba.c b/drivers/acpi/arm64/amba.c
> index 587061b0fd2f..6d24a8f7914b 100644
> --- a/drivers/acpi/arm64/amba.c
> +++ b/drivers/acpi/arm64/amba.c
> @@ -25,7 +25,6 @@ static const struct acpi_device_id amba_id_list[] = {
> {"ARMHC501", 0}, /* ARM CoreSight ETR */
> {"ARMHC502", 0}, /* ARM CoreSight STM */
> {"ARMHC503", 0}, /* ARM CoreSight Debug */
> - {"ARMHC979", 0}, /* ARM CoreSight TPIU */
> {"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */
> {"", 0},
> };
> diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
> index 29024f880fda..4117475f8889 100644
> --- a/drivers/hwtracing/coresight/coresight-tpiu.c
> +++ b/drivers/hwtracing/coresight/coresight-tpiu.c
> @@ -5,6 +5,8 @@
> * Description: CoreSight Trace Port Interface Unit driver
> */
>
> +#include <linux/platform_device.h>
> +#include <linux/acpi.h>
nit: Please could you keep them alphabetic order (including the existing
ones below).
> #include <linux/atomic.h>
> #include <linux/kernel.h>
> #include <linux/init.h>
> @@ -52,11 +54,13 @@ DEFINE_CORESIGHT_DEVLIST(tpiu_devs, "tpiu");
> /*
> * @base: memory mapped base address for this component.
> * @atclk: optional clock for the core parts of the TPIU.
> + * @pclk: APB clock if present, otherwise NULL
> * @csdev: component vitals needed by the framework.
> */
> struct tpiu_drvdata {
> void __iomem *base;
> struct clk *atclk;
> + struct clk *pclk;
> struct coresight_device *csdev;
> spinlock_t spinlock;
> };
> @@ -122,14 +126,12 @@ static const struct coresight_ops tpiu_cs_ops = {
> .sink_ops = &tpiu_sink_ops,
> };
>
> -static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
> +static int __tpiu_probe(struct device *dev, struct resource *res)
> {
> int ret;
> void __iomem *base;
> - struct device *dev = &adev->dev;
> struct coresight_platform_data *pdata = NULL;
> struct tpiu_drvdata *drvdata;
> - struct resource *res = &adev->res;
> struct coresight_desc desc = { 0 };
>
> desc.name = coresight_alloc_device_name(&tpiu_devs, dev);
> @@ -142,12 +144,16 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
>
> spin_lock_init(&drvdata->spinlock);
>
> - drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
> + drvdata->atclk = devm_clk_get(dev, "atclk"); /* optional */
> if (!IS_ERR(drvdata->atclk)) {
> ret = clk_prepare_enable(drvdata->atclk);
> if (ret)
> return ret;
> }
> +
> + drvdata->pclk = coresight_get_enable_apb_pclk(dev);
> + if (IS_ERR(drvdata->pclk))
> + return -ENODEV;
> dev_set_drvdata(dev, drvdata);
>
> /* Validity for the resource is already checked by the AMBA core */
> @@ -173,21 +179,34 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
> desc.dev = dev;
> drvdata->csdev = coresight_register(&desc);
>
> - if (!IS_ERR(drvdata->csdev)) {
> - pm_runtime_put(&adev->dev);
> + if (!IS_ERR(drvdata->csdev))
> return 0;
> - }
>
> return PTR_ERR(drvdata->csdev);
> }
>
> -static void tpiu_remove(struct amba_device *adev)
> +static int tpiu_probe(struct amba_device *adev, const struct amba_id *id)
> {
> - struct tpiu_drvdata *drvdata = dev_get_drvdata(&adev->dev);
> + int ret;
> +
> + ret = __tpiu_probe(&adev->dev, &adev->res);
> + if (!ret)
> + pm_runtime_put(&adev->dev);
> + return ret;
> +}
> +
> +static void __tpiu_remove(struct device *dev)
> +{
> + struct tpiu_drvdata *drvdata = dev_get_drvdata(dev);
>
> coresight_unregister(drvdata->csdev);
> }
>
> +static void tpiu_remove(struct amba_device *adev)
> +{
> + __tpiu_remove(&adev->dev);
> +}
> +
> #ifdef CONFIG_PM
> static int tpiu_runtime_suspend(struct device *dev)
> {
> @@ -196,6 +215,8 @@ static int tpiu_runtime_suspend(struct device *dev)
> if (drvdata && !IS_ERR(drvdata->atclk))
> clk_disable_unprepare(drvdata->atclk);
>
> + if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
> + clk_disable_unprepare(drvdata->pclk);
> return 0;
> }
>
> @@ -206,6 +227,8 @@ static int tpiu_runtime_resume(struct device *dev)
> if (drvdata && !IS_ERR(drvdata->atclk))
> clk_prepare_enable(drvdata->atclk);
>
> + if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
> + clk_prepare_enable(drvdata->pclk);
> return 0;
> }
> #endif
> @@ -245,7 +268,67 @@ static struct amba_driver tpiu_driver = {
> .id_table = tpiu_ids,
> };
>
> -module_amba_driver(tpiu_driver);
> +static int tpiu_platform_probe(struct platform_device *pdev)
> +{
> + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + int ret;
> +
> + pm_runtime_get_noresume(&pdev->dev);
> + pm_runtime_set_active(&pdev->dev);
> + pm_runtime_enable(&pdev->dev);
> +
> + ret = __tpiu_probe(&pdev->dev, res);
> + pm_runtime_put(&pdev->dev);
> + if (ret)
> + pm_runtime_disable(&pdev->dev);
> +
> + return ret;
> +}
> +
> +static int tpiu_platform_remove(struct platform_device *pdev)
> +{
> + struct tpiu_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
> +
> + if (WARN_ON(!drvdata))
> + return -ENODEV;
> +
> + __tpiu_remove(&pdev->dev);
> + pm_runtime_disable(&pdev->dev);
> + if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
Same as the previous patches.
Suzuki
> + clk_put(drvdata->pclk);
> + return 0;
> +}
> +
> +#ifdef CONFIG_ACPI
> +static const struct acpi_device_id tpiu_acpi_ids[] = {
> + {"ARMHC979", 0, 0, 0}, /* ARM CoreSight TPIU */
> + {}
> +};
> +MODULE_DEVICE_TABLE(acpi, tpiu_acpi_ids);
> +#endif
> +
> +static struct platform_driver tpiu_platform_driver = {
> + .probe = tpiu_platform_probe,
> + .remove = tpiu_platform_remove,
> + .driver = {
> + .name = "coresight-tpiu-platform",
> + .acpi_match_table = ACPI_PTR(tpiu_acpi_ids),
> + .suppress_bind_attrs = true,
> + .pm = &tpiu_dev_pm_ops,
> + },
> +};
> +
> +static int __init tpiu_init(void)
> +{
> + return coresight_init_driver("tpiu", &tpiu_driver, &tpiu_platform_driver);
> +}
> +
> +static void __exit tpiu_exit(void)
> +{
> + coresight_remove_driver(&tpiu_driver, &tpiu_platform_driver);
> +}
> +module_init(tpiu_init);
> +module_exit(tpiu_exit);
>
> MODULE_AUTHOR("Pratik Patel <pratikp at codeaurora.org>");
> MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier at linaro.org>");
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