diff mbox series

[V4,05/11] coresight: replicator: Move ACPI support from AMBA driver to platform driver

Message ID 20240123054608.1790189-6-anshuman.khandual@arm.com (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series coresight: Move remaining AMBA ACPI devices into platform driver | expand

Commit Message

Anshuman Khandual Jan. 23, 2024, 5:46 a.m. UTC
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 repliacator 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.

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 V4:

- Added pm_runtime_disable() in replicator_platform_probe()
- Changed replicator_platform_remove() for platform_driver->remove_new()

 drivers/acpi/arm64/amba.c                     |  1 -
 .../coresight/coresight-replicator.c          | 81 ++++++++++---------
 2 files changed, 43 insertions(+), 39 deletions(-)

Comments

Suzuki K Poulose Feb. 15, 2024, 11:23 a.m. UTC | #1
Hi Anshuman

On 23/01/2024 05:46, 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 repliacator 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.
> 
> 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>

I think the patch is doing three different things:

1) Use new helper to register/remove AMBA/Platform drivers
2) Refactor replicator_probe() to make sure it can be reused for 
platform/amba driver, by moving the pm_runtime_put() to the callers.
3) Actually moving the ACPI driver to Platform driver

While (1) and (3) are obvious, (2) gave me hard time to review this
patch, without proper description. If you don't mind, are you able to
split the patch and add proper description of the 3 changes mentioned
above.


Kind regards
Suzuki

> ---
> Changes in V4:
> 
> - Added pm_runtime_disable() in replicator_platform_probe()
> - Changed replicator_platform_remove() for platform_driver->remove_new()
> 
>   drivers/acpi/arm64/amba.c                     |  1 -
>   .../coresight/coresight-replicator.c          | 81 ++++++++++---------
>   2 files changed, 43 insertions(+), 39 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 91d93060dda5..9b5f52725f43 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
> @@ -285,7 +291,6 @@ 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))
> @@ -301,29 +306,33 @@ 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)
>   {
> -	replicator_remove(&pdev->dev);
> +	struct replicator_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
> +
> +	if (drvdata)
> +		replicator_remove(&pdev->dev);
> +
>   	pm_runtime_disable(&pdev->dev);
> +	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
> +		clk_put(drvdata->pclk);
>   }
>   
>   #ifdef CONFIG_PM
> @@ -334,6 +343,8 @@ 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 +355,8 @@ 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);
>   	return 0;
>   }
>   #endif
> @@ -353,31 +366,32 @@ static const struct dev_pm_ops replicator_dev_pm_ops = {
>   			   replicator_runtime_resume, NULL)
>   };
>   
> -static const struct of_device_id static_replicator_match[] = {
> +static const struct of_device_id replicator_match[] = {
>   	{.compatible = "arm,coresight-replicator"},
>   	{.compatible = "arm,coresight-static-replicator"},
>   	{}
>   };
>   
> -MODULE_DEVICE_TABLE(of, static_replicator_match);
> +MODULE_DEVICE_TABLE(of, replicator_match);
>   
>   #ifdef CONFIG_ACPI
> -static const struct acpi_device_id static_replicator_acpi_ids[] = {
> +static const struct acpi_device_id replicator_acpi_ids[] = {
>   	{"ARMHC985", 0}, /* ARM CoreSight Static Replicator */
> +	{"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
>   	{}
>   };
>   
> -MODULE_DEVICE_TABLE(acpi, static_replicator_acpi_ids);
> +MODULE_DEVICE_TABLE(acpi, replicator_acpi_ids);
>   #endif
>   
> -static struct platform_driver static_replicator_driver = {
> -	.probe          = static_replicator_probe,
> -	.remove_new     = static_replicator_remove,
> +static struct platform_driver replicator_driver = {
> +	.probe          = replicator_platform_probe,
> +	.remove_new     = replicator_platform_remove,
>   	.driver         = {
> -		.name   = "coresight-static-replicator",
> +		.name   = "coresight-replicator",
>   		/* THIS_MODULE is taken care of by platform_driver_register() */
> -		.of_match_table = of_match_ptr(static_replicator_match),
> -		.acpi_match_table = ACPI_PTR(static_replicator_acpi_ids),
> +		.of_match_table = of_match_ptr(replicator_match),
> +		.acpi_match_table = ACPI_PTR(replicator_acpi_ids),
>   		.pm	= &replicator_dev_pm_ops,
>   		.suppress_bind_attrs = true,
>   	},
> @@ -386,7 +400,13 @@ static struct platform_driver static_replicator_driver = {
>   static int dynamic_replicator_probe(struct amba_device *adev,
>   				    const struct amba_id *id)
>   {
> -	return replicator_probe(&adev->dev, &adev->res);
> +	int ret;
> +
> +	ret = replicator_probe(&adev->dev, &adev->res);
> +	if (!ret)
> +		pm_runtime_put(&adev->dev);
> +
> +	return ret;
>   }
>   
>   static void dynamic_replicator_remove(struct amba_device *adev)
> @@ -416,27 +436,12 @@ static struct amba_driver dynamic_replicator_driver = {
>   
>   static int __init replicator_init(void)
>   {
> -	int ret;
> -
> -	ret = platform_driver_register(&static_replicator_driver);
> -	if (ret) {
> -		pr_info("Error registering platform driver\n");
> -		return ret;
> -	}
> -
> -	ret = amba_driver_register(&dynamic_replicator_driver);
> -	if (ret) {
> -		pr_info("Error registering amba driver\n");
> -		platform_driver_unregister(&static_replicator_driver);
> -	}
> -
> -	return ret;
> +	return coresight_init_driver("replicator", &dynamic_replicator_driver, &replicator_driver);
>   }
>   
>   static void __exit replicator_exit(void)
>   {
> -	platform_driver_unregister(&static_replicator_driver);
> -	amba_driver_unregister(&dynamic_replicator_driver);
> +	coresight_remove_driver(&dynamic_replicator_driver, &replicator_driver);
>   }
>   
>   module_init(replicator_init);
Suzuki K Poulose Feb. 15, 2024, 11:25 a.m. UTC | #2
On 15/02/2024 11:23, Suzuki K Poulose wrote:
> Hi Anshuman
> 
> On 23/01/2024 05:46, 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 repliacator 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.
>>
>> 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>
> 
> I think the patch is doing three different things:
> 
> 1) Use new helper to register/remove AMBA/Platform drivers
> 2) Refactor replicator_probe() to make sure it can be reused for 
> platform/amba driver, by moving the pm_runtime_put() to the callers.
> 3) Actually moving the ACPI driver to Platform driver
> 
> While (1) and (3) are obvious, (2) gave me hard time to review this
> patch, without proper description. If you don't mind, are you able to
> split the patch and add proper description of the 3 changes mentioned
> above.
> 

You could even move (1) for all the existing drivers into a single patch
or even fold it with the patch that introduces the helpers. That way it
is cleaner and easier to review. And (2) & (3) could be in the same 
patch for each driver, but please add something in the description for (2).

Suzuki

> 
> Kind regards
> Suzuki
> 
>> ---
>> Changes in V4:
>>
>> - Added pm_runtime_disable() in replicator_platform_probe()
>> - Changed replicator_platform_remove() for platform_driver->remove_new()
>>
>>   drivers/acpi/arm64/amba.c                     |  1 -
>>   .../coresight/coresight-replicator.c          | 81 ++++++++++---------
>>   2 files changed, 43 insertions(+), 39 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 91d93060dda5..9b5f52725f43 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
>> @@ -285,7 +291,6 @@ 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))
>> @@ -301,29 +306,33 @@ 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)
>>   {
>> -    replicator_remove(&pdev->dev);
>> +    struct replicator_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
>> +
>> +    if (drvdata)
>> +        replicator_remove(&pdev->dev);
>> +
>>       pm_runtime_disable(&pdev->dev);
>> +    if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
>> +        clk_put(drvdata->pclk);
>>   }
>>   #ifdef CONFIG_PM
>> @@ -334,6 +343,8 @@ 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 +355,8 @@ 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);
>>       return 0;
>>   }
>>   #endif
>> @@ -353,31 +366,32 @@ static const struct dev_pm_ops 
>> replicator_dev_pm_ops = {
>>                  replicator_runtime_resume, NULL)
>>   };
>> -static const struct of_device_id static_replicator_match[] = {
>> +static const struct of_device_id replicator_match[] = {
>>       {.compatible = "arm,coresight-replicator"},
>>       {.compatible = "arm,coresight-static-replicator"},
>>       {}
>>   };
>> -MODULE_DEVICE_TABLE(of, static_replicator_match);
>> +MODULE_DEVICE_TABLE(of, replicator_match);
>>   #ifdef CONFIG_ACPI
>> -static const struct acpi_device_id static_replicator_acpi_ids[] = {
>> +static const struct acpi_device_id replicator_acpi_ids[] = {
>>       {"ARMHC985", 0}, /* ARM CoreSight Static Replicator */
>> +    {"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
>>       {}
>>   };
>> -MODULE_DEVICE_TABLE(acpi, static_replicator_acpi_ids);
>> +MODULE_DEVICE_TABLE(acpi, replicator_acpi_ids);
>>   #endif
>> -static struct platform_driver static_replicator_driver = {
>> -    .probe          = static_replicator_probe,
>> -    .remove_new     = static_replicator_remove,
>> +static struct platform_driver replicator_driver = {
>> +    .probe          = replicator_platform_probe,
>> +    .remove_new     = replicator_platform_remove,
>>       .driver         = {
>> -        .name   = "coresight-static-replicator",
>> +        .name   = "coresight-replicator",
>>           /* THIS_MODULE is taken care of by 
>> platform_driver_register() */
>> -        .of_match_table = of_match_ptr(static_replicator_match),
>> -        .acpi_match_table = ACPI_PTR(static_replicator_acpi_ids),
>> +        .of_match_table = of_match_ptr(replicator_match),
>> +        .acpi_match_table = ACPI_PTR(replicator_acpi_ids),
>>           .pm    = &replicator_dev_pm_ops,
>>           .suppress_bind_attrs = true,
>>       },
>> @@ -386,7 +400,13 @@ static struct platform_driver 
>> static_replicator_driver = {
>>   static int dynamic_replicator_probe(struct amba_device *adev,
>>                       const struct amba_id *id)
>>   {
>> -    return replicator_probe(&adev->dev, &adev->res);
>> +    int ret;
>> +
>> +    ret = replicator_probe(&adev->dev, &adev->res);
>> +    if (!ret)
>> +        pm_runtime_put(&adev->dev);
>> +
>> +    return ret;
>>   }
>>   static void dynamic_replicator_remove(struct amba_device *adev)
>> @@ -416,27 +436,12 @@ static struct amba_driver 
>> dynamic_replicator_driver = {
>>   static int __init replicator_init(void)
>>   {
>> -    int ret;
>> -
>> -    ret = platform_driver_register(&static_replicator_driver);
>> -    if (ret) {
>> -        pr_info("Error registering platform driver\n");
>> -        return ret;
>> -    }
>> -
>> -    ret = amba_driver_register(&dynamic_replicator_driver);
>> -    if (ret) {
>> -        pr_info("Error registering amba driver\n");
>> -        platform_driver_unregister(&static_replicator_driver);
>> -    }
>> -
>> -    return ret;
>> +    return coresight_init_driver("replicator", 
>> &dynamic_replicator_driver, &replicator_driver);
>>   }
>>   static void __exit replicator_exit(void)
>>   {
>> -    platform_driver_unregister(&static_replicator_driver);
>> -    amba_driver_unregister(&dynamic_replicator_driver);
>> +    coresight_remove_driver(&dynamic_replicator_driver, 
>> &replicator_driver);
>>   }
>>   module_init(replicator_init);
>
Anshuman Khandual Feb. 19, 2024, 2:52 a.m. UTC | #3
On 2/15/24 16:55, Suzuki K Poulose wrote:
> On 15/02/2024 11:23, Suzuki K Poulose wrote:
>> Hi Anshuman
>>
>> On 23/01/2024 05:46, 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 repliacator 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.
>>>
>>> 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>
>>
>> I think the patch is doing three different things:
>>
>> 1) Use new helper to register/remove AMBA/Platform drivers
>> 2) Refactor replicator_probe() to make sure it can be reused for platform/amba driver, by moving the pm_runtime_put() to the callers.
>> 3) Actually moving the ACPI driver to Platform driver
>>
>> While (1) and (3) are obvious, (2) gave me hard time to review this
>> patch, without proper description. If you don't mind, are you able to
>> split the patch and add proper description of the 3 changes mentioned
>> above.
>>
> 
> You could even move (1) for all the existing drivers into a single patch
> or even fold it with the patch that introduces the helpers. That way it

There are only two existing coresight devices with both AMBA and platform
drivers available i.e replicator and funnel. Such devices could use these
new helpers right from the beginning. As you mentioned earlier such changes
might be folded back into the patch adding the helpers.

But coresight devices such as catu, tpiu, tmc, stm and debug don't have
platform drivers to begin with. Hence the helpers could only be used in
their respective patches adding platform drivers.

> is cleaner and easier to review. And (2) & (3) could be in the same patch for each driver, but please add something in the description for (2).

Please find the updated commit message here, does this look okay ?

    coresight: replicator: Move ACPI support from AMBA driver to platform driver

    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.
diff mbox series

Patch

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 91d93060dda5..9b5f52725f43 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
@@ -285,7 +291,6 @@  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))
@@ -301,29 +306,33 @@  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)
 {
-	replicator_remove(&pdev->dev);
+	struct replicator_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
+
+	if (drvdata)
+		replicator_remove(&pdev->dev);
+
 	pm_runtime_disable(&pdev->dev);
+	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
+		clk_put(drvdata->pclk);
 }
 
 #ifdef CONFIG_PM
@@ -334,6 +343,8 @@  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 +355,8 @@  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);
 	return 0;
 }
 #endif
@@ -353,31 +366,32 @@  static const struct dev_pm_ops replicator_dev_pm_ops = {
 			   replicator_runtime_resume, NULL)
 };
 
-static const struct of_device_id static_replicator_match[] = {
+static const struct of_device_id replicator_match[] = {
 	{.compatible = "arm,coresight-replicator"},
 	{.compatible = "arm,coresight-static-replicator"},
 	{}
 };
 
-MODULE_DEVICE_TABLE(of, static_replicator_match);
+MODULE_DEVICE_TABLE(of, replicator_match);
 
 #ifdef CONFIG_ACPI
-static const struct acpi_device_id static_replicator_acpi_ids[] = {
+static const struct acpi_device_id replicator_acpi_ids[] = {
 	{"ARMHC985", 0}, /* ARM CoreSight Static Replicator */
+	{"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
 	{}
 };
 
-MODULE_DEVICE_TABLE(acpi, static_replicator_acpi_ids);
+MODULE_DEVICE_TABLE(acpi, replicator_acpi_ids);
 #endif
 
-static struct platform_driver static_replicator_driver = {
-	.probe          = static_replicator_probe,
-	.remove_new     = static_replicator_remove,
+static struct platform_driver replicator_driver = {
+	.probe          = replicator_platform_probe,
+	.remove_new     = replicator_platform_remove,
 	.driver         = {
-		.name   = "coresight-static-replicator",
+		.name   = "coresight-replicator",
 		/* THIS_MODULE is taken care of by platform_driver_register() */
-		.of_match_table = of_match_ptr(static_replicator_match),
-		.acpi_match_table = ACPI_PTR(static_replicator_acpi_ids),
+		.of_match_table = of_match_ptr(replicator_match),
+		.acpi_match_table = ACPI_PTR(replicator_acpi_ids),
 		.pm	= &replicator_dev_pm_ops,
 		.suppress_bind_attrs = true,
 	},
@@ -386,7 +400,13 @@  static struct platform_driver static_replicator_driver = {
 static int dynamic_replicator_probe(struct amba_device *adev,
 				    const struct amba_id *id)
 {
-	return replicator_probe(&adev->dev, &adev->res);
+	int ret;
+
+	ret = replicator_probe(&adev->dev, &adev->res);
+	if (!ret)
+		pm_runtime_put(&adev->dev);
+
+	return ret;
 }
 
 static void dynamic_replicator_remove(struct amba_device *adev)
@@ -416,27 +436,12 @@  static struct amba_driver dynamic_replicator_driver = {
 
 static int __init replicator_init(void)
 {
-	int ret;
-
-	ret = platform_driver_register(&static_replicator_driver);
-	if (ret) {
-		pr_info("Error registering platform driver\n");
-		return ret;
-	}
-
-	ret = amba_driver_register(&dynamic_replicator_driver);
-	if (ret) {
-		pr_info("Error registering amba driver\n");
-		platform_driver_unregister(&static_replicator_driver);
-	}
-
-	return ret;
+	return coresight_init_driver("replicator", &dynamic_replicator_driver, &replicator_driver);
 }
 
 static void __exit replicator_exit(void)
 {
-	platform_driver_unregister(&static_replicator_driver);
-	amba_driver_unregister(&dynamic_replicator_driver);
+	coresight_remove_driver(&dynamic_replicator_driver, &replicator_driver);
 }
 
 module_init(replicator_init);