[PATCH V6 05/11] coresight: replicator: Move ACPI support from AMBA driver to platform driver
Suzuki K Poulose
suzuki.poulose at arm.com
Wed Mar 13 02:41:42 PDT 2024
On 13/03/2024 02:31, Anshuman Khandual wrote:
>
>
> On 3/12/24 20:09, Suzuki K Poulose wrote:
>> On 12/03/2024 10:23, Anshuman Khandual wrote:
>>> Add support for the dynamic replicator device in the platform driver, which
>>> can then be used on ACPI based platforms. This change would now allow
>>> runtime power management for replicator devices on ACPI based systems.
>>>
>>> The driver would try to enable the APB clock if available. Also, rename the
>>> code to reflect the fact that it now handles both static and dynamic
>>> replicators. But first this refactors replicator_probe() making sure it can
>>> be used both for platform and AMBA drivers, by moving the pm_runtime_put()
>>> 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 clk_disable_unprepare() for pclk in replicator_probe() error path
>>> - Added WARN_ON(!drvdata) check in replicator_platform_remove()
>>> - Added additional elements for acpi_device_id[]
>>>
>>> drivers/acpi/arm64/amba.c | 1 -
>>> .../coresight/coresight-replicator.c | 68 ++++++++++++-------
>>> 2 files changed, 45 insertions(+), 24 deletions(-)
>>>
>>> diff --git a/drivers/acpi/arm64/amba.c b/drivers/acpi/arm64/amba.c
>>> index 171b5c2c7edd..270f4e3819a2 100644
>>> --- a/drivers/acpi/arm64/amba.c
>>> +++ b/drivers/acpi/arm64/amba.c
>>> @@ -27,7 +27,6 @@ static const struct acpi_device_id amba_id_list[] = {
>>> {"ARMHC503", 0}, /* ARM CoreSight Debug */
>>> {"ARMHC979", 0}, /* ARM CoreSight TPIU */
>>> {"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */
>>> - {"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
>>> {"ARMHC9CA", 0}, /* ARM CoreSight CATU */
>>> {"ARMHC9FF", 0}, /* ARM CoreSight Dynamic Funnel */
>>> {"", 0},
>>> diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
>>> index ddb530a8436f..ed9be5435f94 100644
>>> --- a/drivers/hwtracing/coresight/coresight-replicator.c
>>> +++ b/drivers/hwtracing/coresight/coresight-replicator.c
>>> @@ -31,6 +31,7 @@ DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator");
>>> * @base: memory mapped base address for this component. Also indicates
>>> * whether this one is programmable or not.
>>> * @atclk: optional clock for the core parts of the replicator.
>>> + * @pclk: APB clock if present, otherwise NULL
>>> * @csdev: component vitals needed by the framework
>>> * @spinlock: serialize enable/disable operations.
>>> * @check_idfilter_val: check if the context is lost upon clock removal.
>>> @@ -38,6 +39,7 @@ DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator");
>>> struct replicator_drvdata {
>>> void __iomem *base;
>>> struct clk *atclk;
>>> + struct clk *pclk;
>>> struct coresight_device *csdev;
>>> spinlock_t spinlock;
>>> bool check_idfilter_val;
>>> @@ -243,6 +245,10 @@ static int replicator_probe(struct device *dev, struct resource *res)
>>> return ret;
>>> }
>>> + drvdata->pclk = coresight_get_enable_apb_pclk(dev);
>>> + if (IS_ERR(drvdata->pclk))
>>> + return -ENODEV;
>>> +
>>> /*
>>> * Map the device base for dynamic-replicator, which has been
>>> * validated by AMBA core
>>> @@ -285,11 +291,12 @@ static int replicator_probe(struct device *dev, struct resource *res)
>>> }
>>> replicator_reset(drvdata);
>>> - pm_runtime_put(dev);
>>> out_disable_clk:
>>> if (ret && !IS_ERR_OR_NULL(drvdata->atclk))
>>> clk_disable_unprepare(drvdata->atclk);
>>> + if (ret && !IS_ERR_OR_NULL(drvdata->pclk))
>>> + clk_disable_unprepare(drvdata->pclk);
>>> return ret;
>>> }
>>> @@ -301,29 +308,34 @@ static int replicator_remove(struct device *dev)
>>> return 0;
>>> }
>>> -static int static_replicator_probe(struct platform_device *pdev)
>>> +static int replicator_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);
>>> - /* Static replicators do not have programming base */
>>> - ret = replicator_probe(&pdev->dev, NULL);
>>> -
>>> - if (ret) {
>>> - pm_runtime_put_noidle(&pdev->dev);
>>> + ret = replicator_probe(&pdev->dev, res);
>>> + pm_runtime_put(&pdev->dev);
>>> + if (ret)
>>> pm_runtime_disable(&pdev->dev);
>>> - }
>>> return ret;
>>> }
>>> -static void static_replicator_remove(struct platform_device *pdev)
>>> +static void replicator_platform_remove(struct platform_device *pdev)
>>> {
>>> + struct replicator_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
>>> +
>>> + if (WARN_ON(!drvdata))
>>> + return;
>>> +
>>> replicator_remove(&pdev->dev);
>>> pm_runtime_disable(&pdev->dev);
>>> + if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
>>> + clk_put(drvdata->pclk);
The comment below applies here. We already return for !drvdata, so you
don't need a duplicate check.
>>> }
>>> #ifdef CONFIG_PM
>>> @@ -334,6 +346,8 @@ static int replicator_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;
>>> }
>>> @@ -344,6 +358,8 @@ static int replicator_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);
>>
>> nit: drvdata is != NULL, so could drop it
> But we already have a similar check for drvdata->atclk above, would not
> dropping drvdata for drvdata->pclk cause inconsistency and asymmetry ?
Sorry, I meant this for above. See above.
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