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.
Cc: Lorenzo Pieralisi lpieralisi@kernel.org Cc: Sudeep Holla sudeep.holla@arm.com Cc: Suzuki K Poulose suzuki.poulose@arm.com Cc: Mike Leach mike.leach@linaro.org Cc: James Clark james.clark@arm.com Cc: linux-acpi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: coresight@lists.linaro.org Tested-by: Sudeep Holla sudeep.holla@arm.com # Boot and driver probe only Acked-by: Sudeep Holla sudeep.holla@arm.com # For ACPI related changes Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com --- Changes in V3:
- Added commnets for 'drvdata->pclk' - Used coresight_init_driver()/coresight_remove_driver() helpers instead - Dropped pm_runtime_put() from __tpiu_probe() - Added pm_runtime_put() on success path in tpiu_probe() - Added pm_runtime_put() on success/error paths in tpiu_platform_probe()
drivers/acpi/arm64/amba.c | 1 - drivers/hwtracing/coresight/coresight-tpiu.c | 99 ++++++++++++++++++-- 2 files changed, 89 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 59eac93fd6bb..ddb214838239 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> #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; };
@@ -114,14 +118,12 @@ 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); @@ -132,12 +134,16 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id) if (!drvdata) return -ENOMEM;
- 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 */ @@ -163,21 +169,34 @@ 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) +{ + 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(&adev->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) { @@ -186,6 +205,8 @@ 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; }
@@ -196,6 +217,8 @@ 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 @@ -235,7 +258,63 @@ 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); + return ret; +} + +static int tpiu_platform_remove(struct platform_device *pdev) +{ + struct tpiu_drvdata *drvdata = dev_get_drvdata(&pdev->dev); + + if (drvdata) + __tpiu_remove(&pdev->dev); + + pm_runtime_disable(&pdev->dev); + if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk)) + clk_put(drvdata->pclk); + return 0; +} + +#ifdef CONFIG_ACPI +static const struct acpi_device_id tpiu_acpi_ids[] = { + {"ARMHC979", 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@codeaurora.org"); MODULE_AUTHOR("Mathieu Poirier mathieu.poirier@linaro.org");