[PATCH 0/4] perf/arm_cspmu: Fixes and cleanups

[PATCH 0/4] perf/arm_cspmu: Fixes and cleanups

[Robin Murphy]

Hi all,

I've been working on adding support for the 64-bit extension and
devicetree probing[1], which I'm not posting yet since it's still
untested and may need a bit more work. However I think these preparatory
patches stand up well enough on their own so could land sooner.

Thanks,
Robin.

[1] https://gitlab.arm.com/linux-arm/linux-rm/-/commits/cspmu-dev/


Robin Murphy (4):
  perf/arm_cspmu: Fix event attribute type
  ACPI/APMT: Don't register invalid resource
  perf/arm_cspmu: Clean up ACPI dependency
  perf/arm_cspmu: Decouple APMT dependency

 drivers/acpi/arm64/apmt.c          | 10 +++--
 drivers/perf/arm_cspmu/Kconfig     |  3 +-
 drivers/perf/arm_cspmu/arm_cspmu.c | 70 +++++++++++++-----------------
 drivers/perf/arm_cspmu/arm_cspmu.h |  4 +-
 4 files changed, 39 insertions(+), 48 deletions(-)

-- 
2.39.2.101.g768bb238c484.dirty


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[PATCH 1/4] perf/arm_cspmu: Fix event attribute type

[Robin Murphy]

ARM_CSPMU_EVENT_ATTR() defines a struct perf_pmu_events_attr, so
arm_cspmu_sysfs_event_show() should not be interpreting it as struct
dev_ext_attribute.

Fixes: e37dfd65731d ("perf: arm_cspmu: Add support for ARM CoreSight PMU driver")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/perf/arm_cspmu/arm_cspmu.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index a3f1c410b417..72dc7a9e1ca8 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -189,10 +189,10 @@ static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu)
 ssize_t arm_cspmu_sysfs_event_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
-	struct dev_ext_attribute *eattr =
-		container_of(attr, struct dev_ext_attribute, attr);
-	return sysfs_emit(buf, "event=0x%llx\n",
-			  (unsigned long long)eattr->var);
+	struct perf_pmu_events_attr *pmu_attr;
+
+	pmu_attr = container_of(attr, typeof(*pmu_attr), attr);
+	return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id);
 }
 EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_event_show);
 
-- 
2.39.2.101.g768bb238c484.dirty


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Re: [PATCH 1/4] perf/arm_cspmu: Fix event attribute type

[Suzuki K Poulose]

On 01/06/2023 12:59, Robin Murphy wrote:
> ARM_CSPMU_EVENT_ATTR() defines a struct perf_pmu_events_attr, so
> arm_cspmu_sysfs_event_show() should not be interpreting it as struct
> dev_ext_attribute.
> 
> Fixes: e37dfd65731d ("perf: arm_cspmu: Add support for ARM CoreSight PMU driver")
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   drivers/perf/arm_cspmu/arm_cspmu.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
> index a3f1c410b417..72dc7a9e1ca8 100644
> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c
> @@ -189,10 +189,10 @@ static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu)
>   ssize_t arm_cspmu_sysfs_event_show(struct device *dev,
>   				struct device_attribute *attr, char *buf)
>   {
> -	struct dev_ext_attribute *eattr =
> -		container_of(attr, struct dev_ext_attribute, attr);
> -	return sysfs_emit(buf, "event=0x%llx\n",
> -			  (unsigned long long)eattr->var);
> +	struct perf_pmu_events_attr *pmu_attr;
> +
> +	pmu_attr = container_of(attr, typeof(*pmu_attr), attr);
> +	return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id);
>   }

Thanks for catching this !  The other option would be to, which was
the original intention.

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.h 
b/drivers/perf/arm_cspmu/arm_cspmu.h
index 51323b175a4a..b5e454be95b3 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.h
+++ b/drivers/perf/arm_cspmu/arm_cspmu.h
@@ -32,7 +32,7 @@
         ARM_CSPMU_EXT_ATTR(_name, arm_cspmu_sysfs_format_show, (char 
*)_config)

  #define ARM_CSPMU_EVENT_ATTR(_name, _config)			                   \
-       PMU_EVENT_ATTR_ID(_name, arm_cspmu_sysfs_event_show, _config)
+       ARM_CSPMU_EXT_ATTR(_name, arm_cspmu_sysfs_event_show, 
(void*)(unsigned long)_config)


  /* Default event id mask */

Either way,

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>


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Re: [PATCH 1/4] perf/arm_cspmu: Fix event attribute type

[Ilkka Koskinen]

On Thu, 1 Jun 2023, Robin Murphy wrote:
> ARM_CSPMU_EVENT_ATTR() defines a struct perf_pmu_events_attr, so
> arm_cspmu_sysfs_event_show() should not be interpreting it as struct
> dev_ext_attribute.
>
> Fixes: e37dfd65731d ("perf: arm_cspmu: Add support for ARM CoreSight PMU driver")
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>

Reviewed-and-tested-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>

> ---
> drivers/perf/arm_cspmu/arm_cspmu.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
> index a3f1c410b417..72dc7a9e1ca8 100644
> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c
> @@ -189,10 +189,10 @@ static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu)
> ssize_t arm_cspmu_sysfs_event_show(struct device *dev,
> 				struct device_attribute *attr, char *buf)
> {
> -	struct dev_ext_attribute *eattr =
> -		container_of(attr, struct dev_ext_attribute, attr);
> -	return sysfs_emit(buf, "event=0x%llx\n",
> -			  (unsigned long long)eattr->var);
> +	struct perf_pmu_events_attr *pmu_attr;
> +
> +	pmu_attr = container_of(attr, typeof(*pmu_attr), attr);
> +	return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id);
> }
> EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_event_show);
>
> -- 
> 2.39.2.101.g768bb238c484.dirty
>
>

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[PATCH 2/4] ACPI/APMT: Don't register invalid resource

[Robin Murphy]

Don't register a resource for the second page unless the dual-page
extension flag is actually present to say it's valid.

CC: Lorenzo Pieralisi <lpieralisi@kernel.org>
CC: Hanjun Guo <guohanjun@huawei.com>
CC: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---

Not a critical fix, since the driver currently works around this itself,
but patch #4 would like to clean that up.

 drivers/acpi/arm64/apmt.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c
index 8cab69fa5d59..aa7d5c3c0dd8 100644
--- a/drivers/acpi/arm64/apmt.c
+++ b/drivers/acpi/arm64/apmt.c
@@ -35,11 +35,13 @@ static int __init apmt_init_resources(struct resource *res,
 
 	num_res++;
 
-	res[num_res].start = node->base_address1;
-	res[num_res].end = node->base_address1 + SZ_4K - 1;
-	res[num_res].flags = IORESOURCE_MEM;
+	if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) {
+		res[num_res].start = node->base_address1;
+		res[num_res].end = node->base_address1 + SZ_4K - 1;
+		res[num_res].flags = IORESOURCE_MEM;
 
-	num_res++;
+		num_res++;
+	}
 
 	if (node->ovflw_irq != 0) {
 		trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE);
-- 
2.39.2.101.g768bb238c484.dirty


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Re: [PATCH 2/4] ACPI/APMT: Don't register invalid resource

[Suzuki K Poulose]

On 01/06/2023 12:59, Robin Murphy wrote:
> Don't register a resource for the second page unless the dual-page
> extension flag is actually present to say it's valid.
> 
> CC: Lorenzo Pieralisi <lpieralisi@kernel.org>
> CC: Hanjun Guo <guohanjun@huawei.com>
> CC: Sudeep Holla <sudeep.holla@arm.com>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> 
> Not a critical fix, since the driver currently works around this itself,
> but patch #4 would like to clean that up.
> 
>   drivers/acpi/arm64/apmt.c | 10 ++++++----
>   1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c
> index 8cab69fa5d59..aa7d5c3c0dd8 100644
> --- a/drivers/acpi/arm64/apmt.c
> +++ b/drivers/acpi/arm64/apmt.c
> @@ -35,11 +35,13 @@ static int __init apmt_init_resources(struct resource *res,
>   
>   	num_res++;
>   
> -	res[num_res].start = node->base_address1;
> -	res[num_res].end = node->base_address1 + SZ_4K - 1;
> -	res[num_res].flags = IORESOURCE_MEM;
> +	if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) {
> +		res[num_res].start = node->base_address1;
> +		res[num_res].end = node->base_address1 + SZ_4K - 1;
> +		res[num_res].flags = IORESOURCE_MEM;
>   
> -	num_res++;
> +		num_res++;
> +	}
>   
>   	if (node->ovflw_irq != 0) {
>   		trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE);

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>

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Re: [PATCH 2/4] ACPI/APMT: Don't register invalid resource

[Hanjun Guo]

On 2023/6/1 19:59, Robin Murphy wrote:
> Don't register a resource for the second page unless the dual-page
> extension flag is actually present to say it's valid.
> 
> CC: Lorenzo Pieralisi <lpieralisi@kernel.org>
> CC: Hanjun Guo <guohanjun@huawei.com>
> CC: Sudeep Holla <sudeep.holla@arm.com>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> 
> Not a critical fix, since the driver currently works around this itself,
> but patch #4 would like to clean that up.
> 
>   drivers/acpi/arm64/apmt.c | 10 ++++++----
>   1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c
> index 8cab69fa5d59..aa7d5c3c0dd8 100644
> --- a/drivers/acpi/arm64/apmt.c
> +++ b/drivers/acpi/arm64/apmt.c
> @@ -35,11 +35,13 @@ static int __init apmt_init_resources(struct resource *res,
>   
>   	num_res++;
>   
> -	res[num_res].start = node->base_address1;
> -	res[num_res].end = node->base_address1 + SZ_4K - 1;
> -	res[num_res].flags = IORESOURCE_MEM;
> +	if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) {
> +		res[num_res].start = node->base_address1;
> +		res[num_res].end = node->base_address1 + SZ_4K - 1;
> +		res[num_res].flags = IORESOURCE_MEM;
>   
> -	num_res++;
> +		num_res++;
> +	}
>   
>   	if (node->ovflw_irq != 0) {
>   		trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE);

Good catch,

Reviewed-by: Hanjun Guo <guohanjun@huawei.com>

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Re: [PATCH 2/4] ACPI/APMT: Don't register invalid resource

[Ilkka Koskinen]

On Thu, 1 Jun 2023, Robin Murphy wrote:
> Don't register a resource for the second page unless the dual-page
> extension flag is actually present to say it's valid.
>
> CC: Lorenzo Pieralisi <lpieralisi@kernel.org>
> CC: Hanjun Guo <guohanjun@huawei.com>
> CC: Sudeep Holla <sudeep.holla@arm.com>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>

Reviewed-and-tested-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>

> ---
>
> Not a critical fix, since the driver currently works around this itself,
> but patch #4 would like to clean that up.
>
> drivers/acpi/arm64/apmt.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c
> index 8cab69fa5d59..aa7d5c3c0dd8 100644
> --- a/drivers/acpi/arm64/apmt.c
> +++ b/drivers/acpi/arm64/apmt.c
> @@ -35,11 +35,13 @@ static int __init apmt_init_resources(struct resource *res,
>
> 	num_res++;
>
> -	res[num_res].start = node->base_address1;
> -	res[num_res].end = node->base_address1 + SZ_4K - 1;
> -	res[num_res].flags = IORESOURCE_MEM;
> +	if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) {
> +		res[num_res].start = node->base_address1;
> +		res[num_res].end = node->base_address1 + SZ_4K - 1;
> +		res[num_res].flags = IORESOURCE_MEM;
>
> -	num_res++;
> +		num_res++;
> +	}
>
> 	if (node->ovflw_irq != 0) {
> 		trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE);
> -- 
> 2.39.2.101.g768bb238c484.dirty
>
>

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[PATCH 3/4] perf/arm_cspmu: Clean up ACPI dependency

[Robin Murphy]

Build-wise, the ACPI dependency consists of only a couple of things
which could probably stand being factored out into ACPI helpers anyway.
However for the immediate concern of working towards Devicetree support
here, it's easy enough to make a few tweaks to contain the affected code
locally, such that we can relax the Kconfig dependency.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/perf/arm_cspmu/Kconfig     |  3 +--
 drivers/perf/arm_cspmu/arm_cspmu.c | 17 +++++++++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/perf/arm_cspmu/Kconfig b/drivers/perf/arm_cspmu/Kconfig
index 0b316fe69a45..25d25ded0983 100644
--- a/drivers/perf/arm_cspmu/Kconfig
+++ b/drivers/perf/arm_cspmu/Kconfig
@@ -4,8 +4,7 @@
 
 config ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU
 	tristate "ARM Coresight Architecture PMU"
-	depends on ARM64 && ACPI
-	depends on ACPI_APMT || COMPILE_TEST
+	depends on ARM64 || COMPILE_TEST
 	help
 	  Provides support for performance monitoring unit (PMU) devices
 	  based on ARM CoreSight PMU architecture. Note that this PMU
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index 72dc7a9e1ca8..3b91115c376d 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -28,7 +28,6 @@
 #include <linux/module.h>
 #include <linux/perf_event.h>
 #include <linux/platform_device.h>
-#include <acpi/processor.h>
 
 #include "arm_cspmu.h"
 #include "nvidia_cspmu.h"
@@ -1075,6 +1074,9 @@ static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
 	return 0;
 }
 
+#if defined(CONFIG_ACPI) && defined(CONFIG_ARM64)
+#include <acpi/processor.h>
+
 static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
 {
 	u32 acpi_uid;
@@ -1099,7 +1101,7 @@ static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
 	return -ENODEV;
 }
 
-static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
+static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
 {
 	struct device *dev;
 	struct acpi_apmt_node *apmt_node;
@@ -1135,6 +1137,17 @@ static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
 
 	return 0;
 }
+#else
+static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
+{
+	return -ENODEV;
+}
+#endif
+
+static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
+{
+	return arm_cspmu_acpi_get_cpus(cspmu);
+}
 
 static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
 {
-- 
2.39.2.101.g768bb238c484.dirty


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Re: [PATCH 3/4] perf/arm_cspmu: Clean up ACPI dependency

[Suzuki K Poulose]

On 01/06/2023 12:59, Robin Murphy wrote:
> Build-wise, the ACPI dependency consists of only a couple of things
> which could probably stand being factored out into ACPI helpers anyway.
> However for the immediate concern of working towards Devicetree support
> here, it's easy enough to make a few tweaks to contain the affected code
> locally, such that we can relax the Kconfig dependency.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   drivers/perf/arm_cspmu/Kconfig     |  3 +--
>   drivers/perf/arm_cspmu/arm_cspmu.c | 17 +++++++++++++++--
>   2 files changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/perf/arm_cspmu/Kconfig b/drivers/perf/arm_cspmu/Kconfig
> index 0b316fe69a45..25d25ded0983 100644
> --- a/drivers/perf/arm_cspmu/Kconfig
> +++ b/drivers/perf/arm_cspmu/Kconfig
> @@ -4,8 +4,7 @@
>   
>   config ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU
>   	tristate "ARM Coresight Architecture PMU"
> -	depends on ARM64 && ACPI
> -	depends on ACPI_APMT || COMPILE_TEST
> +	depends on ARM64 || COMPILE_TEST
>   	help
>   	  Provides support for performance monitoring unit (PMU) devices
>   	  based on ARM CoreSight PMU architecture. Note that this PMU
> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
> index 72dc7a9e1ca8..3b91115c376d 100644
> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c
> @@ -28,7 +28,6 @@
>   #include <linux/module.h>
>   #include <linux/perf_event.h>
>   #include <linux/platform_device.h>
> -#include <acpi/processor.h>
>   
>   #include "arm_cspmu.h"
>   #include "nvidia_cspmu.h"
> @@ -1075,6 +1074,9 @@ static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
>   	return 0;
>   }
>   
> +#if defined(CONFIG_ACPI) && defined(CONFIG_ARM64)
> +#include <acpi/processor.h>
> +
>   static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
>   {
>   	u32 acpi_uid;
> @@ -1099,7 +1101,7 @@ static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
>   	return -ENODEV;
>   }
>   
> -static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
> +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
>   {
>   	struct device *dev;
>   	struct acpi_apmt_node *apmt_node;
> @@ -1135,6 +1137,17 @@ static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
>   
>   	return 0;
>   }
> +#else
> +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
> +{
> +	return -ENODEV;
> +}
> +#endif
> +
> +static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
> +{
> +	return arm_cspmu_acpi_get_cpus(cspmu);
> +}
>   
>   static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
>   {


Reviewed-and-Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>


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Re: [PATCH 3/4] perf/arm_cspmu: Clean up ACPI dependency

[Ilkka Koskinen]

On Thu, 1 Jun 2023, Robin Murphy wrote:
> Build-wise, the ACPI dependency consists of only a couple of things
> which could probably stand being factored out into ACPI helpers anyway.
> However for the immediate concern of working towards Devicetree support
> here, it's easy enough to make a few tweaks to contain the affected code
> locally, such that we can relax the Kconfig dependency.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>

Reviewed-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>

> ---
> drivers/perf/arm_cspmu/Kconfig     |  3 +--
> drivers/perf/arm_cspmu/arm_cspmu.c | 17 +++++++++++++++--
> 2 files changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/perf/arm_cspmu/Kconfig b/drivers/perf/arm_cspmu/Kconfig
> index 0b316fe69a45..25d25ded0983 100644
> --- a/drivers/perf/arm_cspmu/Kconfig
> +++ b/drivers/perf/arm_cspmu/Kconfig
> @@ -4,8 +4,7 @@
>
> config ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU
> 	tristate "ARM Coresight Architecture PMU"
> -	depends on ARM64 && ACPI
> -	depends on ACPI_APMT || COMPILE_TEST
> +	depends on ARM64 || COMPILE_TEST
> 	help
> 	  Provides support for performance monitoring unit (PMU) devices
> 	  based on ARM CoreSight PMU architecture. Note that this PMU
> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
> index 72dc7a9e1ca8..3b91115c376d 100644
> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c
> @@ -28,7 +28,6 @@
> #include <linux/module.h>
> #include <linux/perf_event.h>
> #include <linux/platform_device.h>
> -#include <acpi/processor.h>
>
> #include "arm_cspmu.h"
> #include "nvidia_cspmu.h"
> @@ -1075,6 +1074,9 @@ static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
> 	return 0;
> }
>
> +#if defined(CONFIG_ACPI) && defined(CONFIG_ARM64)
> +#include <acpi/processor.h>
> +
> static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
> {
> 	u32 acpi_uid;
> @@ -1099,7 +1101,7 @@ static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
> 	return -ENODEV;
> }
>
> -static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
> +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
> {
> 	struct device *dev;
> 	struct acpi_apmt_node *apmt_node;
> @@ -1135,6 +1137,17 @@ static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
>
> 	return 0;
> }
> +#else
> +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
> +{
> +	return -ENODEV;
> +}
> +#endif
> +
> +static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
> +{
> +	return arm_cspmu_acpi_get_cpus(cspmu);
> +}
>
> static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
> {
> -- 
> 2.39.2.101.g768bb238c484.dirty
>
>

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[PATCH 4/4] perf/arm_cspmu: Decouple APMT dependency

[Robin Murphy]

The functional paths of the driver need not care about ACPI, so abstract
the property of atomic doubleword access as its own flag (repacking the
structure for a better fit). We also do not need to go poking directly
at the APMT for standard resources which the ACPI layer has already
dealt with, so deal with the optional MMIO page and interrupt in the
normal firmware-agnostic manner. The few remaining portions of probing
that *are* APMT-specific can still easily retrieve the APMT pointer as
needed without us having to carry a duplicate copy around everywhere.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/perf/arm_cspmu/arm_cspmu.c | 45 ++++++++----------------------
 drivers/perf/arm_cspmu/arm_cspmu.h |  4 +--
 2 files changed, 13 insertions(+), 36 deletions(-)

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index 3b91115c376d..f8daf252a488 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -100,10 +100,6 @@
 #define ARM_CSPMU_ACTIVE_CPU_MASK		0x0
 #define ARM_CSPMU_ASSOCIATED_CPU_MASK		0x1
 
-/* Check if field f in flags is set with value v */
-#define CHECK_APMT_FLAG(flags, f, v) \
-	((flags & (ACPI_APMT_FLAGS_ ## f)) == (ACPI_APMT_FLAGS_ ## f ## _ ## v))
-
 /* Check and use default if implementer doesn't provide attribute callback */
 #define CHECK_DEFAULT_IMPL_OPS(ops, callback)			\
 	do {							\
@@ -155,12 +151,6 @@ static u64 read_reg64_hilohi(const void __iomem *addr, u32 max_poll_count)
 	return val;
 }
 
-/* Check if PMU supports 64-bit single copy atomic. */
-static inline bool supports_64bit_atomics(const struct arm_cspmu *cspmu)
-{
-	return CHECK_APMT_FLAG(cspmu->apmt_node->flags, ATOMIC, SUPP);
-}
-
 /* Check if cycle counter is supported. */
 static inline bool supports_cycle_counter(const struct arm_cspmu *cspmu)
 {
@@ -319,7 +309,7 @@ static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu)
 	static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
 
 	dev = cspmu->dev;
-	apmt_node = cspmu->apmt_node;
+	apmt_node = dev_get_platdata(dev);
 	pmu_type = apmt_node->type;
 
 	if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) {
@@ -396,8 +386,8 @@ static const struct impl_match impl_match[] = {
 static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
 {
 	int ret;
-	struct acpi_apmt_node *apmt_node = cspmu->apmt_node;
 	struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
+	struct acpi_apmt_node *apmt_node = dev_get_platdata(cspmu->dev);
 	const struct impl_match *match = impl_match;
 
 	/*
@@ -719,7 +709,7 @@ static u64 arm_cspmu_read_counter(struct perf_event *event)
 		offset = counter_offset(sizeof(u64), event->hw.idx);
 		counter_addr = cspmu->base1 + offset;
 
-		return supports_64bit_atomics(cspmu) ?
+		return cspmu->has_atomic_dword ?
 			       readq(counter_addr) :
 			       read_reg64_hilohi(counter_addr, HILOHI_MAX_POLL);
 	}
@@ -910,24 +900,18 @@ static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
 {
 	struct acpi_apmt_node *apmt_node;
 	struct arm_cspmu *cspmu;
-	struct device *dev;
-
-	dev = &pdev->dev;
-	apmt_node = *(struct acpi_apmt_node **)dev_get_platdata(dev);
-	if (!apmt_node) {
-		dev_err(dev, "failed to get APMT node\n");
-		return NULL;
-	}
+	struct device *dev = &pdev->dev;
 
 	cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL);
 	if (!cspmu)
 		return NULL;
 
 	cspmu->dev = dev;
-	cspmu->apmt_node = apmt_node;
-
 	platform_set_drvdata(pdev, cspmu);
 
+	apmt_node = dev_get_platdata(dev);
+	cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC;
+
 	return cspmu;
 }
 
@@ -935,11 +919,9 @@ static int arm_cspmu_init_mmio(struct arm_cspmu *cspmu)
 {
 	struct device *dev;
 	struct platform_device *pdev;
-	struct acpi_apmt_node *apmt_node;
 
 	dev = cspmu->dev;
 	pdev = to_platform_device(dev);
-	apmt_node = cspmu->apmt_node;
 
 	/* Base address for page 0. */
 	cspmu->base0 = devm_platform_ioremap_resource(pdev, 0);
@@ -950,7 +932,7 @@ static int arm_cspmu_init_mmio(struct arm_cspmu *cspmu)
 
 	/* Base address for page 1 if supported. Otherwise point to page 0. */
 	cspmu->base1 = cspmu->base0;
-	if (CHECK_APMT_FLAG(apmt_node->flags, DUAL_PAGE, SUPP)) {
+	if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
 		cspmu->base1 = devm_platform_ioremap_resource(pdev, 1);
 		if (IS_ERR(cspmu->base1)) {
 			dev_err(dev, "ioremap failed for page-1 resource\n");
@@ -1047,19 +1029,14 @@ static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
 	int irq, ret;
 	struct device *dev;
 	struct platform_device *pdev;
-	struct acpi_apmt_node *apmt_node;
 
 	dev = cspmu->dev;
 	pdev = to_platform_device(dev);
-	apmt_node = cspmu->apmt_node;
 
 	/* Skip IRQ request if the PMU does not support overflow interrupt. */
-	if (apmt_node->ovflw_irq == 0)
-		return 0;
-
-	irq = platform_get_irq(pdev, 0);
+	irq = platform_get_irq_optional(pdev, 0);
 	if (irq < 0)
-		return irq;
+		return irq == -ENXIO ? 0 : irq;
 
 	ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
 			       IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev),
@@ -1109,7 +1086,7 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
 	int cpu;
 
 	dev = cspmu->pmu.dev;
-	apmt_node = cspmu->apmt_node;
+	apmt_node = dev_get_platdata(dev);
 	affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY;
 
 	if (affinity_flag == ACPI_APMT_FLAGS_AFFINITY_PROC) {
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.h b/drivers/perf/arm_cspmu/arm_cspmu.h
index 51323b175a4a..7892e587f606 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.h
+++ b/drivers/perf/arm_cspmu/arm_cspmu.h
@@ -118,16 +118,16 @@ struct arm_cspmu_impl {
 struct arm_cspmu {
 	struct pmu pmu;
 	struct device *dev;
-	struct acpi_apmt_node *apmt_node;
 	const char *name;
 	const char *identifier;
 	void __iomem *base0;
 	void __iomem *base1;
-	int irq;
 	cpumask_t associated_cpus;
 	cpumask_t active_cpu;
 	struct hlist_node cpuhp_node;
+	int irq;
 
+	bool has_atomic_dword;
 	u32 pmcfgr;
 	u32 num_logical_ctrs;
 	u32 num_set_clr_reg;
-- 
2.39.2.101.g768bb238c484.dirty


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Re: [PATCH 4/4] perf/arm_cspmu: Decouple APMT dependency

[Suzuki K Poulose]

On 01/06/2023 12:59, Robin Murphy wrote:
> The functional paths of the driver need not care about ACPI, so abstract
> the property of atomic doubleword access as its own flag (repacking the
> structure for a better fit). We also do not need to go poking directly
> at the APMT for standard resources which the ACPI layer has already
> dealt with, so deal with the optional MMIO page and interrupt in the
> normal firmware-agnostic manner. The few remaining portions of probing
> that *are* APMT-specific can still easily retrieve the APMT pointer as
> needed without us having to carry a duplicate copy around everywhere.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>



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Re: [PATCH 4/4] perf/arm_cspmu: Decouple APMT dependency

[Ilkka Koskinen]

Hi Robin,

I have a couple of comments below

On Thu, 1 Jun 2023, Robin Murphy wrote:
> The functional paths of the driver need not care about ACPI, so abstract
> the property of atomic doubleword access as its own flag (repacking the
> structure for a better fit). We also do not need to go poking directly
> at the APMT for standard resources which the ACPI layer has already
> dealt with, so deal with the optional MMIO page and interrupt in the
> normal firmware-agnostic manner. The few remaining portions of probing
> that *are* APMT-specific can still easily retrieve the APMT pointer as
> needed without us having to carry a duplicate copy around everywhere.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> drivers/perf/arm_cspmu/arm_cspmu.c | 45 ++++++++----------------------
> drivers/perf/arm_cspmu/arm_cspmu.h |  4 +--
> 2 files changed, 13 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
> index 3b91115c376d..f8daf252a488 100644
> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c

...

> @@ -319,7 +309,7 @@ static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu)
> 	static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
>
> 	dev = cspmu->dev;
> -	apmt_node = cspmu->apmt_node;
> +	apmt_node = dev_get_platdata(dev);

Was platdata changed too? If not, I think this should be

 	apmt_node = *(struct acpi_apmt_node **) dev_get_platdata(dev);

> 	pmu_type = apmt_node->type;
>
> 	if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) {
> @@ -396,8 +386,8 @@ static const struct impl_match impl_match[] = {
> static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
> {
> 	int ret;
> -	struct acpi_apmt_node *apmt_node = cspmu->apmt_node;
> 	struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
> +	struct acpi_apmt_node *apmt_node = dev_get_platdata(cspmu->dev);

Ditto

> 	const struct impl_match *match = impl_match;
>
> 	/*

...

> @@ -910,24 +900,18 @@ static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
> {
> 	struct acpi_apmt_node *apmt_node;
> 	struct arm_cspmu *cspmu;
> -	struct device *dev;
> -
> -	dev = &pdev->dev;
> -	apmt_node = *(struct acpi_apmt_node **)dev_get_platdata(dev);
> -	if (!apmt_node) {
> -		dev_err(dev, "failed to get APMT node\n");
> -		return NULL;
> -	}
> +	struct device *dev = &pdev->dev;
>
> 	cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL);
> 	if (!cspmu)
> 		return NULL;
>
> 	cspmu->dev = dev;
> -	cspmu->apmt_node = apmt_node;
> -
> 	platform_set_drvdata(pdev, cspmu);
>
> +	apmt_node = dev_get_platdata(dev);

Ditto

> +	cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC;
> +
> 	return cspmu;
> }

...

> @@ -1047,19 +1029,14 @@ static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
> 	int irq, ret;
> 	struct device *dev;
> 	struct platform_device *pdev;
> -	struct acpi_apmt_node *apmt_node;
>
> 	dev = cspmu->dev;
> 	pdev = to_platform_device(dev);
> -	apmt_node = cspmu->apmt_node;
>
> 	/* Skip IRQ request if the PMU does not support overflow interrupt. */
> -	if (apmt_node->ovflw_irq == 0)
> -		return 0;
> -
> -	irq = platform_get_irq(pdev, 0);
> +	irq = platform_get_irq_optional(pdev, 0);
> 	if (irq < 0)
> -		return irq;
> +		return irq == -ENXIO ? 0 : irq;
>
> 	ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
> 			       IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev),
> @@ -1109,7 +1086,7 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
> 	int cpu;
>
> 	dev = cspmu->pmu.dev;

You didn't touch this one but shouldn't this be

 	dev = cspmu->dev;

> -	apmt_node = cspmu->apmt_node;
> +	apmt_node = dev_get_platdata(dev);

Ditto

> 	affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY;


Otherwise the patch looks good to me.

Cheers, Ilkka

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Re: [PATCH 4/4] perf/arm_cspmu: Decouple APMT dependency

[Robin Murphy]

On 2023-06-05 08:12, Ilkka Koskinen wrote:
> 
> Hi Robin,
> 
> I have a couple of comments below
> 
> On Thu, 1 Jun 2023, Robin Murphy wrote:
>> The functional paths of the driver need not care about ACPI, so abstract
>> the property of atomic doubleword access as its own flag (repacking the
>> structure for a better fit). We also do not need to go poking directly
>> at the APMT for standard resources which the ACPI layer has already
>> dealt with, so deal with the optional MMIO page and interrupt in the
>> normal firmware-agnostic manner. The few remaining portions of probing
>> that *are* APMT-specific can still easily retrieve the APMT pointer as
>> needed without us having to carry a duplicate copy around everywhere.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>> drivers/perf/arm_cspmu/arm_cspmu.c | 45 ++++++++----------------------
>> drivers/perf/arm_cspmu/arm_cspmu.h |  4 +--
>> 2 files changed, 13 insertions(+), 36 deletions(-)
>>
>> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c 
>> b/drivers/perf/arm_cspmu/arm_cspmu.c
>> index 3b91115c376d..f8daf252a488 100644
>> --- a/drivers/perf/arm_cspmu/arm_cspmu.c
>> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c
> 
> ...
> 
>> @@ -319,7 +309,7 @@ static const char *arm_cspmu_get_name(const struct 
>> arm_cspmu *cspmu)
>>     static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
>>
>>     dev = cspmu->dev;
>> -    apmt_node = cspmu->apmt_node;
>> +    apmt_node = dev_get_platdata(dev);
> 
> Was platdata changed too? If not, I think this should be
> 
>      apmt_node = *(struct acpi_apmt_node **) dev_get_platdata(dev);

Oof, indeed it looks like I got the wrong thing into my head at the 
critical moment :(

Clearly this deserves a nice helpful wrapper so we only have to think 
about the nasty casting once...

>>     pmu_type = apmt_node->type;
>>
>>     if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) {
>> @@ -396,8 +386,8 @@ static const struct impl_match impl_match[] = {
>> static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
>> {
>>     int ret;
>> -    struct acpi_apmt_node *apmt_node = cspmu->apmt_node;
>>     struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
>> +    struct acpi_apmt_node *apmt_node = dev_get_platdata(cspmu->dev);
> 
> Ditto
> 
>>     const struct impl_match *match = impl_match;
>>
>>     /*
> 
> ...
> 
>> @@ -910,24 +900,18 @@ static struct arm_cspmu *arm_cspmu_alloc(struct 
>> platform_device *pdev)
>> {
>>     struct acpi_apmt_node *apmt_node;
>>     struct arm_cspmu *cspmu;
>> -    struct device *dev;
>> -
>> -    dev = &pdev->dev;
>> -    apmt_node = *(struct acpi_apmt_node **)dev_get_platdata(dev);
>> -    if (!apmt_node) {
>> -        dev_err(dev, "failed to get APMT node\n");
>> -        return NULL;
>> -    }
>> +    struct device *dev = &pdev->dev;
>>
>>     cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL);
>>     if (!cspmu)
>>         return NULL;
>>
>>     cspmu->dev = dev;
>> -    cspmu->apmt_node = apmt_node;
>> -
>>     platform_set_drvdata(pdev, cspmu);
>>
>> +    apmt_node = dev_get_platdata(dev);
> 
> Ditto
> 
>> +    cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC;
>> +
>>     return cspmu;
>> }
> 
> ...
> 
>> @@ -1047,19 +1029,14 @@ static int arm_cspmu_request_irq(struct 
>> arm_cspmu *cspmu)
>>     int irq, ret;
>>     struct device *dev;
>>     struct platform_device *pdev;
>> -    struct acpi_apmt_node *apmt_node;
>>
>>     dev = cspmu->dev;
>>     pdev = to_platform_device(dev);
>> -    apmt_node = cspmu->apmt_node;
>>
>>     /* Skip IRQ request if the PMU does not support overflow 
>> interrupt. */
>> -    if (apmt_node->ovflw_irq == 0)
>> -        return 0;
>> -
>> -    irq = platform_get_irq(pdev, 0);
>> +    irq = platform_get_irq_optional(pdev, 0);
>>     if (irq < 0)
>> -        return irq;
>> +        return irq == -ENXIO ? 0 : irq;
>>
>>     ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
>>                    IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev),
>> @@ -1109,7 +1086,7 @@ static int arm_cspmu_acpi_get_cpus(struct 
>> arm_cspmu *cspmu)
>>     int cpu;
>>
>>     dev = cspmu->pmu.dev;
> 
> You didn't touch this one but shouldn't this be
> 
>      dev = cspmu->dev;

Good catch - attributing the error message to the wrong device doesn't 
matter too much currently, but this change does then need it to be 
right. Will fix that too.

Thanks!
Robin.

> 
>> -    apmt_node = cspmu->apmt_node;
>> +    apmt_node = dev_get_platdata(dev);
> 
> Ditto
> 
>>     affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY;
> 
> 
> Otherwise the patch looks good to me.
> 
> Cheers, Ilkka

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