[PATCH V3 07/10] coresight: tpiu: Move ACPI support from AMBA driver to platform driver
Anshuman Khandual
anshuman.khandual at arm.com
Thu Dec 7 21:39:36 PST 2023
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 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
Signed-off-by: Anshuman Khandual <anshuman.khandual at 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 at codeaurora.org>");
MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier at linaro.org>");
--
2.25.1
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