[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

Add a helper to fetch the port/device GPF dvsecs. This is
currently only used for ports, but a later patch to export
dirty count to users will make use of the device one.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
 drivers/cxl/core/pci.c | 38 ++++++++++++++++++++++++++++----------
 drivers/cxl/cxl.h      |  2 ++
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index a5c65f79db18..2226cca3382d 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
 #define GPF_TIMEOUT_BASE_MAX 2
 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port)
+{
+	struct pci_dev *pdev;
+	int dvsec;
+
+	if (!dev_is_pci(dev))
+		return -EINVAL;
+
+	pdev = to_pci_dev(dev);
+	if (!pdev)
+		return -EINVAL;
+
+	dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
+			port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
+	if (!dvsec)
+		pci_warn(pdev, "%s GPF DVSEC not present\n",
+			 port ? "Port" : "Device");
+	return dvsec;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
+
 static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
 {
 	u64 base, scale;
@@ -1116,26 +1137,23 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
 {
 	struct pci_dev *pdev;
 
-	if (!dev_is_pci(dport_dev))
-		return 0;
-
-	pdev = to_pci_dev(dport_dev);
-	if (!pdev || !port)
+	if (!port)
 		return -EINVAL;
 
 	if (!port->gpf_dvsec) {
 		int dvsec;
 
-		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
-						  CXL_DVSEC_PORT_GPF);
-		if (!dvsec) {
-			pci_warn(pdev, "Port GPF DVSEC not present\n");
+		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
+		if (dvsec <= 0)
 			return -EINVAL;
-		}
 
 		port->gpf_dvsec = dvsec;
 	}
 
+	pdev = to_pci_dev(dport_dev);
+	if (!pdev)
+		return -EINVAL;
+
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6baec4ba9141..acbbba41356d 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
 #define __mock static
 #endif
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port);
+
 #endif /* __CXL_H__ */
-- 
2.39.5

[PATCH v3 0/4] cxl: Dirty shutdown followups

[Davidlohr Bueso]

Changes from v2:
  - remove leftover cxl_gpf_device() declaration
  
Changes from v1 (https://lore.kernel.org/linux-cxl/20250205040842.1253616-1-dave@stgolabs.net/):
  - crated a new cxl_gpf_get_dvsec() helper to share for port and dev gpf (DaveJ)
  - renamed cxl_dirty_shutdown_state() to cxl_arm_dirty_shutdown() (DaveJ)
  - exported the cxl_gpf_get_dvsec() symbol used outside of core (Yi, DaveJ)
  - introduced CXL_INVALID_DIRTY_SHUTDOWN_COUNT (DaveJ)
  - use u64 for cxl_nvd->dirty_shutdowns,
  - rename to cxl_nvdimm_setup_dirty_tracking() and use return statements (DaveJ)
  - picked up review tag in patch 4 (DaveJ)

Hi,

Some followup patches to the GPF work. First two patches are from feedback
provided by DaveJ. The third patch adds a $platform/dirty_shutdown sysfs
attribute to expose the count to userspace. Fourth patch adds support
emulating the set shutdown state command for the mock device.

Applies against the -next branch of cxl.git.

Thanks!

Davidlohr Bueso (4):
  cxl/pci: Introduce cxl_gpf_get_dvsec()
  cxl/pmem: Rename cxl_dirty_shutdown_state()
  cxl/pmem: Export dirty shutdown count via sysfs
  tools/testing/cxl: Set Shutdown State support

 Documentation/ABI/testing/sysfs-bus-cxl       | 12 +++
 Documentation/driver-api/cxl/maturity-map.rst |  2 +-
 drivers/cxl/core/mbox.c                       | 25 +++++-
 drivers/cxl/core/pci.c                        | 38 ++++++---
 drivers/cxl/cxl.h                             |  3 +
 drivers/cxl/cxlmem.h                          | 15 +++-
 drivers/cxl/pmem.c                            | 77 +++++++++++++++++--
 tools/testing/cxl/test/mem.c                  | 23 ++++++
 8 files changed, 173 insertions(+), 22 deletions(-)

--
2.39.5

[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

Add a helper to fetch the port/device GPF dvsecs. This is
currently only used for ports, but a later patch to export
dirty count to users will make use of the device one.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
 drivers/cxl/core/pci.c | 38 ++++++++++++++++++++++++++++----------
 drivers/cxl/cxl.h      |  2 ++
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index a5c65f79db18..2226cca3382d 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
 #define GPF_TIMEOUT_BASE_MAX 2
 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port)
+{
+	struct pci_dev *pdev;
+	int dvsec;
+
+	if (!dev_is_pci(dev))
+		return -EINVAL;
+
+	pdev = to_pci_dev(dev);
+	if (!pdev)
+		return -EINVAL;
+
+	dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
+			port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
+	if (!dvsec)
+		pci_warn(pdev, "%s GPF DVSEC not present\n",
+			 port ? "Port" : "Device");
+	return dvsec;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
+
 static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
 {
 	u64 base, scale;
@@ -1116,26 +1137,23 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
 {
 	struct pci_dev *pdev;
 
-	if (!dev_is_pci(dport_dev))
-		return 0;
-
-	pdev = to_pci_dev(dport_dev);
-	if (!pdev || !port)
+	if (!port)
 		return -EINVAL;
 
 	if (!port->gpf_dvsec) {
 		int dvsec;
 
-		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
-						  CXL_DVSEC_PORT_GPF);
-		if (!dvsec) {
-			pci_warn(pdev, "Port GPF DVSEC not present\n");
+		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
+		if (dvsec <= 0)
 			return -EINVAL;
-		}
 
 		port->gpf_dvsec = dvsec;
 	}
 
+	pdev = to_pci_dev(dport_dev);
+	if (!pdev)
+		return -EINVAL;
+
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6baec4ba9141..acbbba41356d 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
 #define __mock static
 #endif
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port);
+
 #endif /* __CXL_H__ */
-- 
2.39.5

[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

Add a helper to fetch the port/device GPF dvsecs. This is
currently only used for ports, but a later patch to export
dirty count to users will make use of the device one.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
 drivers/cxl/core/pci.c | 38 ++++++++++++++++++++++++++++----------
 drivers/cxl/cxl.h      |  2 ++
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index a5c65f79db18..2226cca3382d 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
 #define GPF_TIMEOUT_BASE_MAX 2
 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port)
+{
+	struct pci_dev *pdev;
+	int dvsec;
+
+	if (!dev_is_pci(dev))
+		return -EINVAL;
+
+	pdev = to_pci_dev(dev);
+	if (!pdev)
+		return -EINVAL;
+
+	dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
+			port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
+	if (!dvsec)
+		pci_warn(pdev, "%s GPF DVSEC not present\n",
+			 port ? "Port" : "Device");
+	return dvsec;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
+
 static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
 {
 	u64 base, scale;
@@ -1116,26 +1137,23 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
 {
 	struct pci_dev *pdev;
 
-	if (!dev_is_pci(dport_dev))
-		return 0;
-
-	pdev = to_pci_dev(dport_dev);
-	if (!pdev || !port)
+	if (!port)
 		return -EINVAL;
 
 	if (!port->gpf_dvsec) {
 		int dvsec;
 
-		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
-						  CXL_DVSEC_PORT_GPF);
-		if (!dvsec) {
-			pci_warn(pdev, "Port GPF DVSEC not present\n");
+		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
+		if (dvsec <= 0)
 			return -EINVAL;
-		}
 
 		port->gpf_dvsec = dvsec;
 	}
 
+	pdev = to_pci_dev(dport_dev);
+	if (!pdev)
+		return -EINVAL;
+
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6baec4ba9141..acbbba41356d 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
 #define __mock static
 #endif
 
+int cxl_gpf_get_dvsec(struct device *dev, bool port);
+
 #endif /* __CXL_H__ */
-- 
2.39.5

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Dave Jiang]

On 2/18/25 11:28 PM, Davidlohr Bueso wrote:
> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> ---
>  drivers/cxl/core/pci.c | 38 ++++++++++++++++++++++++++++----------
>  drivers/cxl/cxl.h      |  2 ++
>  2 files changed, 30 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index a5c65f79db18..2226cca3382d 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
>  #define GPF_TIMEOUT_BASE_MAX 2
>  #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
>  
> +int cxl_gpf_get_dvsec(struct device *dev, bool port)

Maybe consider enum instead of bool. That would make it more readable. if not, maybe rename the bool to is_port

> +{
> +	struct pci_dev *pdev;
> +	int dvsec;
> +
> +	if (!dev_is_pci(dev))
> +		return -EINVAL;

Since this function is mostly a wrapper for pci_find_dvsec_capability(), why not have it return type to be u16 and just return 0 here? That way when you check you only need to verify if it's 0 (failed). 

> +
> +	pdev = to_pci_dev(dev);
> +	if (!pdev)
> +		return -EINVAL;

No need to check here. to_pci_dev() does not return a NULL. 

> +
> +	dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> +			port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
> +	if (!dvsec)
> +		pci_warn(pdev, "%s GPF DVSEC not present\n",

why not just dev_warn() since this is cxl code and not PCI core

> +			 port ? "Port" : "Device");
> +	return dvsec;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
> +
>  static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
>  {
>  	u64 base, scale;
> @@ -1116,26 +1137,23 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
>  {
>  	struct pci_dev *pdev;
>  
> -	if (!dev_is_pci(dport_dev))
> -		return 0;
> -
> -	pdev = to_pci_dev(dport_dev);
> -	if (!pdev || !port)
> +	if (!port)
>  		return -EINVAL;
>  
>  	if (!port->gpf_dvsec) {
>  		int dvsec;
>  
> -		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> -						  CXL_DVSEC_PORT_GPF);
> -		if (!dvsec) {
> -			pci_warn(pdev, "Port GPF DVSEC not present\n");
> +		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
> +		if (dvsec <= 0)
>  			return -EINVAL;
> -		}
>  
>  		port->gpf_dvsec = dvsec;
>  	}
>  
> +	pdev = to_pci_dev(dport_dev);
> +	if (!pdev)
> +		return -EINVAL;

No need to check here. macro does not return NULL.

> +
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
>  
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 6baec4ba9141..acbbba41356d 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
>  #define __mock static
>  #endif
>  
> +int cxl_gpf_get_dvsec(struct device *dev, bool port);
> +
>  #endif /* __CXL_H__ */

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

On Wed, 19 Feb 2025, Dave Jiang wrote:

>> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
>> index a5c65f79db18..2226cca3382d 100644
>> --- a/drivers/cxl/core/pci.c
>> +++ b/drivers/cxl/core/pci.c
>> @@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
>>  #define GPF_TIMEOUT_BASE_MAX 2
>>  #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
>>
>> +int cxl_gpf_get_dvsec(struct device *dev, bool port)
>
>Maybe consider enum instead of bool. That would make it more readable. if not, maybe rename the bool to is_port
>
>> +{
>> +	struct pci_dev *pdev;
>> +	int dvsec;
>> +
>> +	if (!dev_is_pci(dev))
>> +		return -EINVAL;
>
>Since this function is mostly a wrapper for pci_find_dvsec_capability(), why not have it return type to be u16 and just return 0 here? That way when you check you only need to verify if it's 0 (failed).

I kind of wanted to not have a u16 return just because it was ugly for cxl general
calls, but yeah it is better to follow the pci call itself, given the name of this
cxl helper is *dvsec*.

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Li Ming]

On 2/19/2025 2:28 PM, Davidlohr Bueso wrote:
> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> ---
>  drivers/cxl/core/pci.c | 38 ++++++++++++++++++++++++++++----------
>  drivers/cxl/cxl.h      |  2 ++
>  2 files changed, 30 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index a5c65f79db18..2226cca3382d 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1072,6 +1072,27 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
>  #define GPF_TIMEOUT_BASE_MAX 2
>  #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
>  
> +int cxl_gpf_get_dvsec(struct device *dev, bool port)
> +{
> +	struct pci_dev *pdev;
> +	int dvsec;
> +
> +	if (!dev_is_pci(dev))
> +		return -EINVAL;
> +
> +	pdev = to_pci_dev(dev);
> +	if (!pdev)
> +		return -EINVAL;
My understanding is checking the returned value of to_pci_dev() is not needed, to_pci_dev() is a container_of() macro. Besides, above already checks if the device is a PCI device.
> +
> +	dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> +			port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
> +	if (!dvsec)
> +		pci_warn(pdev, "%s GPF DVSEC not present\n",
> +			 port ? "Port" : "Device");
> +	return dvsec;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
> +
>  static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
>  {
>  	u64 base, scale;
> @@ -1116,26 +1137,23 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
>  {
>  	struct pci_dev *pdev;
>  
> -	if (!dev_is_pci(dport_dev))
> -		return 0;
> -
> -	pdev = to_pci_dev(dport_dev);
> -	if (!pdev || !port)
> +	if (!port)
>  		return -EINVAL;
>  
>  	if (!port->gpf_dvsec) {
>  		int dvsec;
>  
> -		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> -						  CXL_DVSEC_PORT_GPF);
> -		if (!dvsec) {
> -			pci_warn(pdev, "Port GPF DVSEC not present\n");
> +		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
> +		if (dvsec <= 0)
>  			return -EINVAL;
> -		}
>  
>  		port->gpf_dvsec = dvsec;
>  	}
>  
> +	pdev = to_pci_dev(dport_dev);
> +	if (!pdev)
> +		return -EINVAL;

Same as above.

Other looks good to me, feel free to add

Reviewed-by: Li Ming <ming.li@zohomail.com>

[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

Add a helper to fetch the port/device GPF dvsecs. This is
currently only used for ports, but a later patch to export
dirty count to users will make use of the device one.

Reviewed-by: Li Ming <ming.li@zohomail.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
 drivers/cxl/core/pci.c | 30 ++++++++++++++++++++----------
 drivers/cxl/cxl.h      |  2 ++
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index a5c65f79db18..96fecb799cbc 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -1072,6 +1072,22 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
 #define GPF_TIMEOUT_BASE_MAX 2
 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
 
+u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port)
+{
+	u16 dvsec;
+
+	if (!dev_is_pci(dev))
+		return 0;
+
+	dvsec = pci_find_dvsec_capability(to_pci_dev(dev), PCI_VENDOR_ID_CXL,
+			is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
+	if (!dvsec)
+		dev_warn(dev, "%s GPF DVSEC not present\n",
+			 is_port ? "Port" : "Device");
+	return dvsec;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
+
 static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
 {
 	u64 base, scale;
@@ -1116,26 +1132,20 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
 {
 	struct pci_dev *pdev;
 
-	if (!dev_is_pci(dport_dev))
-		return 0;
-
-	pdev = to_pci_dev(dport_dev);
-	if (!pdev || !port)
+	if (!port)
 		return -EINVAL;
 
 	if (!port->gpf_dvsec) {
 		int dvsec;
 
-		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
-						  CXL_DVSEC_PORT_GPF);
-		if (!dvsec) {
-			pci_warn(pdev, "Port GPF DVSEC not present\n");
+		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
+		if (!dvsec)
 			return -EINVAL;
-		}
 
 		port->gpf_dvsec = dvsec;
 	}
 
+	pdev = to_pci_dev(dport_dev);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6baec4ba9141..29f2ab0d5bf6 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
 #define __mock static
 #endif
 
+u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port);
+
 #endif /* __CXL_H__ */
-- 
2.39.5

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Dave Jiang]

On 2/19/25 6:36 PM, Davidlohr Bueso wrote:
> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Reviewed-by: Li Ming <ming.li@zohomail.com>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  drivers/cxl/core/pci.c | 30 ++++++++++++++++++++----------
>  drivers/cxl/cxl.h      |  2 ++
>  2 files changed, 22 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index a5c65f79db18..96fecb799cbc 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1072,6 +1072,22 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
>  #define GPF_TIMEOUT_BASE_MAX 2
>  #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
>  
> +u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port)
> +{
> +	u16 dvsec;
> +
> +	if (!dev_is_pci(dev))
> +		return 0;
> +
> +	dvsec = pci_find_dvsec_capability(to_pci_dev(dev), PCI_VENDOR_ID_CXL,
> +			is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
> +	if (!dvsec)
> +		dev_warn(dev, "%s GPF DVSEC not present\n",
> +			 is_port ? "Port" : "Device");
> +	return dvsec;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
> +
>  static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
>  {
>  	u64 base, scale;
> @@ -1116,26 +1132,20 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
>  {
>  	struct pci_dev *pdev;
>  
> -	if (!dev_is_pci(dport_dev))
> -		return 0;
> -
> -	pdev = to_pci_dev(dport_dev);
> -	if (!pdev || !port)
> +	if (!port)
>  		return -EINVAL;
>  
>  	if (!port->gpf_dvsec) {
>  		int dvsec;
>  
> -		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> -						  CXL_DVSEC_PORT_GPF);
> -		if (!dvsec) {
> -			pci_warn(pdev, "Port GPF DVSEC not present\n");
> +		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
> +		if (!dvsec)
>  			return -EINVAL;
> -		}
>  
>  		port->gpf_dvsec = dvsec;
>  	}
>  
> +	pdev = to_pci_dev(dport_dev);
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
>  
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 6baec4ba9141..29f2ab0d5bf6 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
>  #define __mock static
>  #endif
>  
> +u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port);
> +
>  #endif /* __CXL_H__ */

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Ira Weiny]

Davidlohr Bueso wrote:
> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Reviewed-by: Li Ming <ming.li@zohomail.com>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>

Reviewed-by: Ira Weiny <ira.weiny@intel.com>

[snip]

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Jonathan Cameron]

On Wed, 19 Feb 2025 17:36:01 -0800
Davidlohr Bueso <dave@stgolabs.net> wrote:

> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Reviewed-by: Li Ming <ming.li@zohomail.com>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Maybe an enum for the port vs device thing would have been nice but
I'm not that bothered and a single use enum is bit nasty.

[PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Davidlohr Bueso]

Add a helper to fetch the port/device GPF dvsecs. This is
currently only used for ports, but a later patch to export
dirty count to users will make use of the device one.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Li Ming <ming.li@zohomail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
---
 drivers/cxl/core/pci.c | 30 ++++++++++++++++++++----------
 drivers/cxl/cxl.h      |  2 ++
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index a5c65f79db18..96fecb799cbc 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -1072,6 +1072,22 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
 #define GPF_TIMEOUT_BASE_MAX 2
 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
 
+u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port)
+{
+	u16 dvsec;
+
+	if (!dev_is_pci(dev))
+		return 0;
+
+	dvsec = pci_find_dvsec_capability(to_pci_dev(dev), PCI_VENDOR_ID_CXL,
+			is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
+	if (!dvsec)
+		dev_warn(dev, "%s GPF DVSEC not present\n",
+			 is_port ? "Port" : "Device");
+	return dvsec;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
+
 static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
 {
 	u64 base, scale;
@@ -1116,26 +1132,20 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
 {
 	struct pci_dev *pdev;
 
-	if (!dev_is_pci(dport_dev))
-		return 0;
-
-	pdev = to_pci_dev(dport_dev);
-	if (!pdev || !port)
+	if (!port)
 		return -EINVAL;
 
 	if (!port->gpf_dvsec) {
 		int dvsec;
 
-		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
-						  CXL_DVSEC_PORT_GPF);
-		if (!dvsec) {
-			pci_warn(pdev, "Port GPF DVSEC not present\n");
+		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
+		if (!dvsec)
 			return -EINVAL;
-		}
 
 		port->gpf_dvsec = dvsec;
 	}
 
+	pdev = to_pci_dev(dport_dev);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
 	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6baec4ba9141..29f2ab0d5bf6 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
 #define __mock static
 #endif
 
+u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port);
+
 #endif /* __CXL_H__ */
-- 
2.39.5

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Fan Ni]

On Wed, Feb 19, 2025 at 05:36:01PM -0800, Davidlohr Bueso wrote:
> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Reviewed-by: Li Ming <ming.li@zohomail.com>
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> ---

Reviewed-by: Fan Ni <fan.ni@samsung.com>

>  drivers/cxl/core/pci.c | 30 ++++++++++++++++++++----------
>  drivers/cxl/cxl.h      |  2 ++
>  2 files changed, 22 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index a5c65f79db18..96fecb799cbc 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1072,6 +1072,22 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c)
>  #define GPF_TIMEOUT_BASE_MAX 2
>  #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */
>  
> +u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port)
> +{
> +	u16 dvsec;
> +
> +	if (!dev_is_pci(dev))
> +		return 0;
> +
> +	dvsec = pci_find_dvsec_capability(to_pci_dev(dev), PCI_VENDOR_ID_CXL,
> +			is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF);
> +	if (!dvsec)
> +		dev_warn(dev, "%s GPF DVSEC not present\n",
> +			 is_port ? "Port" : "Device");
> +	return dvsec;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL");
> +
>  static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase)
>  {
>  	u64 base, scale;
> @@ -1116,26 +1132,20 @@ int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port)
>  {
>  	struct pci_dev *pdev;
>  
> -	if (!dev_is_pci(dport_dev))
> -		return 0;
> -
> -	pdev = to_pci_dev(dport_dev);
> -	if (!pdev || !port)
> +	if (!port)
>  		return -EINVAL;
>  
>  	if (!port->gpf_dvsec) {
>  		int dvsec;
>  
> -		dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
> -						  CXL_DVSEC_PORT_GPF);
> -		if (!dvsec) {
> -			pci_warn(pdev, "Port GPF DVSEC not present\n");
> +		dvsec = cxl_gpf_get_dvsec(dport_dev, true);
> +		if (!dvsec)
>  			return -EINVAL;
> -		}
>  
>  		port->gpf_dvsec = dvsec;
>  	}
>  
> +	pdev = to_pci_dev(dport_dev);
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1);
>  	update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2);
>  
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 6baec4ba9141..29f2ab0d5bf6 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -901,4 +901,6 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
>  #define __mock static
>  #endif
>  
> +u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port);
> +
>  #endif /* __CXL_H__ */
> -- 
> 2.39.5
> 

Re: [PATCH 1/4] cxl/pci: Introduce cxl_gpf_get_dvsec()

[Jonathan Cameron]

On Thu, 20 Feb 2025 14:02:32 -0800
Davidlohr Bueso <dave@stgolabs.net> wrote:

> Add a helper to fetch the port/device GPF dvsecs. This is
> currently only used for ports, but a later patch to export
> dirty count to users will make use of the device one.
> 
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> Reviewed-by: Li Ming <ming.li@zohomail.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

(was in v4 reply)