[PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[Pavan Kumar Linga]

At present IDPF supports only 0x1452 and 0x145C as PF and VF device IDs
on our current generation hardware. Future hardware exposes a new set of
device IDs for each generation. To avoid adding a new device ID for each
generation and to make the driver forward and backward compatible,
make use of the IDPF PCI programming interface to load the driver.

Write and read the VF_ARQBAL mailbox register to find if the current
device is a PF or a VF.

PCI SIG allocated a new programming interface for the IDPF compliant
ethernet network controller devices. It can be found at:
https://members.pcisig.com/wg/PCI-SIG/document/20113
with the document titled as 'PCI Code and ID Assignment Revision 1.16'
or any latest revisions.

Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
---
 drivers/net/ethernet/intel/idpf/idpf.h        |  1 +
 drivers/net/ethernet/intel/idpf/idpf_main.c   | 73 ++++++++++++++-----
 drivers/net/ethernet/intel/idpf/idpf_vf_dev.c | 37 ++++++++++
 3 files changed, 94 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf.h b/drivers/net/ethernet/intel/idpf/idpf.h
index 19a248d5b124..4b8e944994cb 100644
--- a/drivers/net/ethernet/intel/idpf/idpf.h
+++ b/drivers/net/ethernet/intel/idpf/idpf.h
@@ -983,6 +983,7 @@ void idpf_mbx_task(struct work_struct *work);
 void idpf_vc_event_task(struct work_struct *work);
 void idpf_dev_ops_init(struct idpf_adapter *adapter);
 void idpf_vf_dev_ops_init(struct idpf_adapter *adapter);
+int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf);
 int idpf_intr_req(struct idpf_adapter *adapter);
 void idpf_intr_rel(struct idpf_adapter *adapter);
 u16 idpf_get_max_tx_hdr_size(struct idpf_adapter *adapter);
diff --git a/drivers/net/ethernet/intel/idpf/idpf_main.c b/drivers/net/ethernet/intel/idpf/idpf_main.c
index 8c46481d2e1f..b161715e1168 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_main.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_main.c
@@ -7,11 +7,57 @@
 
 #define DRV_SUMMARY	"Intel(R) Infrastructure Data Path Function Linux Driver"
 
+#define IDPF_NETWORK_ETHERNET_PROGIF				0x01
+#define IDPF_CLASS_NETWORK_ETHERNET_PROGIF			\
+	(PCI_CLASS_NETWORK_ETHERNET << 8 | IDPF_NETWORK_ETHERNET_PROGIF)
+
 MODULE_DESCRIPTION(DRV_SUMMARY);
 MODULE_IMPORT_NS("LIBETH");
 MODULE_IMPORT_NS("LIBETH_XDP");
 MODULE_LICENSE("GPL");
 
+/**
+ * idpf_dev_init - Initialize device specific parameters
+ * @adapter: adapter to initialize
+ * @ent: entry in idpf_pci_tbl
+ *
+ * Return: %0 on success, -%errno on failure.
+ */
+static int idpf_dev_init(struct idpf_adapter *adapter,
+			 const struct pci_device_id *ent)
+{
+	u8 is_vf = 0;
+	int err;
+
+	switch (ent->device) {
+	case IDPF_DEV_ID_PF:
+		goto dev_ops_init;
+	case IDPF_DEV_ID_VF:
+		is_vf = 1;
+		goto dev_ops_init;
+	default:
+		if (ent->class == IDPF_CLASS_NETWORK_ETHERNET_PROGIF)
+			goto check_vf;
+
+		return -ENODEV;
+	}
+
+check_vf:
+	err = idpf_is_vf_device(adapter->pdev, &is_vf);
+	if (err)
+		return err;
+
+dev_ops_init:
+	if (is_vf) {
+		idpf_vf_dev_ops_init(adapter);
+		adapter->crc_enable = true;
+	} else {
+		idpf_dev_ops_init(adapter);
+	}
+
+	return 0;
+}
+
 /**
  * idpf_remove - Device removal routine
  * @pdev: PCI device information struct
@@ -165,21 +211,6 @@ static int idpf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	adapter->req_tx_splitq = true;
 	adapter->req_rx_splitq = true;
 
-	switch (ent->device) {
-	case IDPF_DEV_ID_PF:
-		idpf_dev_ops_init(adapter);
-		break;
-	case IDPF_DEV_ID_VF:
-		idpf_vf_dev_ops_init(adapter);
-		adapter->crc_enable = true;
-		break;
-	default:
-		err = -ENODEV;
-		dev_err(&pdev->dev, "Unexpected dev ID 0x%x in idpf probe\n",
-			ent->device);
-		goto err_free;
-	}
-
 	adapter->pdev = pdev;
 	err = pcim_enable_device(pdev);
 	if (err)
@@ -259,11 +290,18 @@ static int idpf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	/* setup msglvl */
 	adapter->msg_enable = netif_msg_init(-1, IDPF_AVAIL_NETIF_M);
 
+	err = idpf_dev_init(adapter, ent);
+	if (err) {
+		dev_err(&pdev->dev, "Unexpected dev ID 0x%x in idpf probe\n",
+			ent->device);
+		goto destroy_vc_event_wq;
+	}
+
 	err = idpf_cfg_hw(adapter);
 	if (err) {
 		dev_err(dev, "Failed to configure HW structure for adapter: %d\n",
 			err);
-		goto err_cfg_hw;
+		goto destroy_vc_event_wq;
 	}
 
 	mutex_init(&adapter->vport_ctrl_lock);
@@ -284,7 +322,7 @@ static int idpf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	return 0;
 
-err_cfg_hw:
+destroy_vc_event_wq:
 	destroy_workqueue(adapter->vc_event_wq);
 err_vc_event_wq_alloc:
 	destroy_workqueue(adapter->stats_wq);
@@ -304,6 +342,7 @@ static int idpf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 static const struct pci_device_id idpf_pci_tbl[] = {
 	{ PCI_VDEVICE(INTEL, IDPF_DEV_ID_PF)},
 	{ PCI_VDEVICE(INTEL, IDPF_DEV_ID_VF)},
+	{ PCI_DEVICE_CLASS(IDPF_CLASS_NETWORK_ETHERNET_PROGIF, 0xffffff)},
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(pci, idpf_pci_tbl);
diff --git a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c b/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
index 4cc58c83688c..5bf9d3ccb624 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
@@ -7,6 +7,43 @@
 
 #define IDPF_VF_ITR_IDX_SPACING		0x40
 
+#define IDPF_VF_TEST_VAL		0xFEED0000
+
+/**
+ * idpf_is_vf_device - Helper to find if it is a VF device
+ * @pdev: PCI device information struct
+ * @is_vf: used to update VF device status
+ *
+ * Return: %0 on success, -%errno on failure.
+ */
+int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf)
+{
+	struct resource mbx_region;
+	resource_size_t mbx_start;
+	void __iomem *mbx_addr;
+	long len;
+
+	resource_set_range(&mbx_region,	VF_BASE, IDPF_VF_MBX_REGION_SZ);
+
+	mbx_start = pci_resource_start(pdev, 0) + mbx_region.start;
+	len = resource_size(&mbx_region);
+
+	mbx_addr = ioremap(mbx_start, len);
+	if (!mbx_addr)
+		return -EIO;
+
+	writel(IDPF_VF_TEST_VAL, mbx_addr + VF_ARQBAL - VF_BASE);
+
+	/* Force memory write to complete before reading it back */
+	wmb();
+
+	*is_vf = readl(mbx_addr + VF_ARQBAL - VF_BASE) == IDPF_VF_TEST_VAL;
+
+	iounmap(mbx_addr);
+
+	return 0;
+}
+
 /**
  * idpf_vf_ctlq_reg_init - initialize default mailbox registers
  * @adapter: adapter structure
-- 
2.43.0

Re: [PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[Przemek Kitszel]

On 8/26/25 19:28, Pavan Kumar Linga wrote:
> At present IDPF supports only 0x1452 and 0x145C as PF and VF device IDs
> on our current generation hardware. Future hardware exposes a new set of
> device IDs for each generation. To avoid adding a new device ID for each
> generation and to make the driver forward and backward compatible,
> make use of the IDPF PCI programming interface to load the driver.
> 
> Write and read the VF_ARQBAL mailbox register to find if the current
> device is a PF or a VF.
> 
> PCI SIG allocated a new programming interface for the IDPF compliant
> ethernet network controller devices. It can be found at:
> https://members.pcisig.com/wg/PCI-SIG/document/20113
> with the document titled as 'PCI Code and ID Assignment Revision 1.16'
> or any latest revisions.
> 
> Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
> Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
> ---
>   drivers/net/ethernet/intel/idpf/idpf.h        |  1 +
>   drivers/net/ethernet/intel/idpf/idpf_main.c   | 73 ++++++++++++++-----
>   drivers/net/ethernet/intel/idpf/idpf_vf_dev.c | 37 ++++++++++
>   3 files changed, 94 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/idpf/idpf.h b/drivers/net/ethernet/intel/idpf/idpf.h
> index 19a248d5b124..4b8e944994cb 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf.h
> +++ b/drivers/net/ethernet/intel/idpf/idpf.h
> @@ -983,6 +983,7 @@ void idpf_mbx_task(struct work_struct *work);
>   void idpf_vc_event_task(struct work_struct *work);
>   void idpf_dev_ops_init(struct idpf_adapter *adapter);
>   void idpf_vf_dev_ops_init(struct idpf_adapter *adapter);
> +int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf);

please change it to *bool

>   int idpf_intr_req(struct idpf_adapter *adapter);
>   void idpf_intr_rel(struct idpf_adapter *adapter);
>   u16 idpf_get_max_tx_hdr_size(struct idpf_adapter *adapter);
> diff --git a/drivers/net/ethernet/intel/idpf/idpf_main.c b/drivers/net/ethernet/intel/idpf/idpf_main.c
> index 8c46481d2e1f..b161715e1168 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf_main.c
> +++ b/drivers/net/ethernet/intel/idpf/idpf_main.c
> @@ -7,11 +7,57 @@
>   
>   #define DRV_SUMMARY	"Intel(R) Infrastructure Data Path Function Linux Driver"
>   
> +#define IDPF_NETWORK_ETHERNET_PROGIF				0x01
> +#define IDPF_CLASS_NETWORK_ETHERNET_PROGIF			\
> +	(PCI_CLASS_NETWORK_ETHERNET << 8 | IDPF_NETWORK_ETHERNET_PROGIF)
> +

[...]

> @@ -304,6 +342,7 @@ static int idpf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>   static const struct pci_device_id idpf_pci_tbl[] = {
>   	{ PCI_VDEVICE(INTEL, IDPF_DEV_ID_PF)},
>   	{ PCI_VDEVICE(INTEL, IDPF_DEV_ID_VF)},
> +	{ PCI_DEVICE_CLASS(IDPF_CLASS_NETWORK_ETHERNET_PROGIF, 0xffffff)},

PCI_ANY or ~0 as last param would be closer to what others use,
in this form it looks like you avoid to be found when someone adds
a new helper for such usage

>   	{ /* Sentinel */ }
>   };
>   MODULE_DEVICE_TABLE(pci, idpf_pci_tbl);
> diff --git a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c b/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
> index 4cc58c83688c..5bf9d3ccb624 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
> +++ b/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
> @@ -7,6 +7,43 @@
>   
>   #define IDPF_VF_ITR_IDX_SPACING		0x40
>   
> +#define IDPF_VF_TEST_VAL		0xFEED0000
> +
> +/**
> + * idpf_is_vf_device - Helper to find if it is a VF device
> + * @pdev: PCI device information struct
> + * @is_vf: used to update VF device status
> + *
> + * Return: %0 on success, -%errno on failure.
> + */
> +int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf)
> +{
> +	struct resource mbx_region;
> +	resource_size_t mbx_start;
> +	void __iomem *mbx_addr;
> +	long len;
> +
> +	resource_set_range(&mbx_region,	VF_BASE, IDPF_VF_MBX_REGION_SZ);
> +
> +	mbx_start = pci_resource_start(pdev, 0) + mbx_region.start;
> +	len = resource_size(&mbx_region);
> +
> +	mbx_addr = ioremap(mbx_start, len);
> +	if (!mbx_addr)
> +		return -EIO;
> +
> +	writel(IDPF_VF_TEST_VAL, mbx_addr + VF_ARQBAL - VF_BASE);
> +
> +	/* Force memory write to complete before reading it back */
> +	wmb();
> +
> +	*is_vf = readl(mbx_addr + VF_ARQBAL - VF_BASE) == IDPF_VF_TEST_VAL;
> +
> +	iounmap(mbx_addr);
> +
> +	return 0;
> +}
> +
>   /**
>    * idpf_vf_ctlq_reg_init - initialize default mailbox registers
>    * @adapter: adapter structure

Re: [PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[Linga, Pavan Kumar]

On 8/26/2025 1:12 PM, Przemek Kitszel wrote:
> On 8/26/25 19:28, Pavan Kumar Linga wrote:
>> At present IDPF supports only 0x1452 and 0x145C as PF and VF device IDs
>> on our current generation hardware. Future hardware exposes a new set of
>> device IDs for each generation. To avoid adding a new device ID for each
>> generation and to make the driver forward and backward compatible,
>> make use of the IDPF PCI programming interface to load the driver.
>>
>> Write and read the VF_ARQBAL mailbox register to find if the current
>> device is a PF or a VF.
>>
>> PCI SIG allocated a new programming interface for the IDPF compliant
>> ethernet network controller devices. It can be found at:
>> https://members.pcisig.com/wg/PCI-SIG/document/20113
>> with the document titled as 'PCI Code and ID Assignment Revision 1.16'
>> or any latest revisions.
>>
>> Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
>> Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
>> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
>> ---
>>   drivers/net/ethernet/intel/idpf/idpf.h        |  1 +
>>   drivers/net/ethernet/intel/idpf/idpf_main.c   | 73 ++++++++++++++-----
>>   drivers/net/ethernet/intel/idpf/idpf_vf_dev.c | 37 ++++++++++
>>   3 files changed, 94 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/idpf/idpf.h b/drivers/net/ 
>> ethernet/intel/idpf/idpf.h
>> index 19a248d5b124..4b8e944994cb 100644
>> --- a/drivers/net/ethernet/intel/idpf/idpf.h
>> +++ b/drivers/net/ethernet/intel/idpf/idpf.h
>> @@ -983,6 +983,7 @@ void idpf_mbx_task(struct work_struct *work);
>>   void idpf_vc_event_task(struct work_struct *work);
>>   void idpf_dev_ops_init(struct idpf_adapter *adapter);
>>   void idpf_vf_dev_ops_init(struct idpf_adapter *adapter);
>> +int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf);
> 
> please change it to *bool

Sure, will fix it.

> 
>>   int idpf_intr_req(struct idpf_adapter *adapter);
>>   void idpf_intr_rel(struct idpf_adapter *adapter);
>>   u16 idpf_get_max_tx_hdr_size(struct idpf_adapter *adapter);
>> diff --git a/drivers/net/ethernet/intel/idpf/idpf_main.c b/drivers/ 
>> net/ethernet/intel/idpf/idpf_main.c
>> index 8c46481d2e1f..b161715e1168 100644
>> --- a/drivers/net/ethernet/intel/idpf/idpf_main.c
>> +++ b/drivers/net/ethernet/intel/idpf/idpf_main.c
>> @@ -7,11 +7,57 @@
>>   #define DRV_SUMMARY    "Intel(R) Infrastructure Data Path Function 
>> Linux Driver"
>> +#define IDPF_NETWORK_ETHERNET_PROGIF                0x01
>> +#define IDPF_CLASS_NETWORK_ETHERNET_PROGIF            \
>> +    (PCI_CLASS_NETWORK_ETHERNET << 8 | IDPF_NETWORK_ETHERNET_PROGIF)
>> +
> 
> [...]
> 
>> @@ -304,6 +342,7 @@ static int idpf_probe(struct pci_dev *pdev, const 
>> struct pci_device_id *ent)
>>   static const struct pci_device_id idpf_pci_tbl[] = {
>>       { PCI_VDEVICE(INTEL, IDPF_DEV_ID_PF)},
>>       { PCI_VDEVICE(INTEL, IDPF_DEV_ID_VF)},
>> +    { PCI_DEVICE_CLASS(IDPF_CLASS_NETWORK_ETHERNET_PROGIF, 0xffffff)},
> 
> PCI_ANY or ~0 as last param would be closer to what others use,
> in this form it looks like you avoid to be found when someone adds
> a new helper for such usage
> 

That makes sense. Will use ~0.

>>       { /* Sentinel */ }
>>   };
>>   MODULE_DEVICE_TABLE(pci, idpf_pci_tbl);
>> diff --git a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c b/drivers/ 
>> net/ethernet/intel/idpf/idpf_vf_dev.c
>> index 4cc58c83688c..5bf9d3ccb624 100644
>> --- a/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
>> +++ b/drivers/net/ethernet/intel/idpf/idpf_vf_dev.c
>> @@ -7,6 +7,43 @@
>>   #define IDPF_VF_ITR_IDX_SPACING        0x40
>> +#define IDPF_VF_TEST_VAL        0xFEED0000
>> +
>> +/**
>> + * idpf_is_vf_device - Helper to find if it is a VF device
>> + * @pdev: PCI device information struct
>> + * @is_vf: used to update VF device status
>> + *
>> + * Return: %0 on success, -%errno on failure.
>> + */
>> +int idpf_is_vf_device(struct pci_dev *pdev, u8 *is_vf)
>> +{
>> +    struct resource mbx_region;
>> +    resource_size_t mbx_start;
>> +    void __iomem *mbx_addr;
>> +    long len;
>> +
>> +    resource_set_range(&mbx_region,    VF_BASE, IDPF_VF_MBX_REGION_SZ);
>> +
>> +    mbx_start = pci_resource_start(pdev, 0) + mbx_region.start;
>> +    len = resource_size(&mbx_region);
>> +
>> +    mbx_addr = ioremap(mbx_start, len);
>> +    if (!mbx_addr)
>> +        return -EIO;
>> +
>> +    writel(IDPF_VF_TEST_VAL, mbx_addr + VF_ARQBAL - VF_BASE);
>> +
>> +    /* Force memory write to complete before reading it back */
>> +    wmb();
>> +
>> +    *is_vf = readl(mbx_addr + VF_ARQBAL - VF_BASE) == IDPF_VF_TEST_VAL;
>> +
>> +    iounmap(mbx_addr);
>> +
>> +    return 0;
>> +}
>> +
>>   /**
>>    * idpf_vf_ctlq_reg_init - initialize default mailbox registers
>>    * @adapter: adapter structure
> 

Thanks,
Pavan

Re: [PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[Simon Horman]

On Tue, Aug 26, 2025 at 10:28:45AM -0700, Pavan Kumar Linga wrote:
> At present IDPF supports only 0x1452 and 0x145C as PF and VF device IDs
> on our current generation hardware. Future hardware exposes a new set of
> device IDs for each generation. To avoid adding a new device ID for each
> generation and to make the driver forward and backward compatible,
> make use of the IDPF PCI programming interface to load the driver.
> 
> Write and read the VF_ARQBAL mailbox register to find if the current
> device is a PF or a VF.
> 
> PCI SIG allocated a new programming interface for the IDPF compliant
> ethernet network controller devices. It can be found at:
> https://members.pcisig.com/wg/PCI-SIG/document/20113
> with the document titled as 'PCI Code and ID Assignment Revision 1.16'
> or any latest revisions.
> 
> Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
> Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>

...

> diff --git a/drivers/net/ethernet/intel/idpf/idpf_main.c b/drivers/net/ethernet/intel/idpf/idpf_main.c
> index 8c46481d2e1f..b161715e1168 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf_main.c
> +++ b/drivers/net/ethernet/intel/idpf/idpf_main.c
> @@ -7,11 +7,57 @@
>  
>  #define DRV_SUMMARY	"Intel(R) Infrastructure Data Path Function Linux Driver"
>  
> +#define IDPF_NETWORK_ETHERNET_PROGIF				0x01
> +#define IDPF_CLASS_NETWORK_ETHERNET_PROGIF			\
> +	(PCI_CLASS_NETWORK_ETHERNET << 8 | IDPF_NETWORK_ETHERNET_PROGIF)
> +
>  MODULE_DESCRIPTION(DRV_SUMMARY);
>  MODULE_IMPORT_NS("LIBETH");
>  MODULE_IMPORT_NS("LIBETH_XDP");
>  MODULE_LICENSE("GPL");
>  
> +/**
> + * idpf_dev_init - Initialize device specific parameters
> + * @adapter: adapter to initialize
> + * @ent: entry in idpf_pci_tbl
> + *
> + * Return: %0 on success, -%errno on failure.
> + */
> +static int idpf_dev_init(struct idpf_adapter *adapter,
> +			 const struct pci_device_id *ent)
> +{
> +	u8 is_vf = 0;
> +	int err;
> +
> +	switch (ent->device) {
> +	case IDPF_DEV_ID_PF:
> +		goto dev_ops_init;
> +	case IDPF_DEV_ID_VF:
> +		is_vf = 1;
> +		goto dev_ops_init;
> +	default:
> +		if (ent->class == IDPF_CLASS_NETWORK_ETHERNET_PROGIF)
> +			goto check_vf;
> +
> +		return -ENODEV;
> +	}
> +
> +check_vf:
> +	err = idpf_is_vf_device(adapter->pdev, &is_vf);
> +	if (err)
> +		return err;
> +
> +dev_ops_init:
> +	if (is_vf) {
> +		idpf_vf_dev_ops_init(adapter);
> +		adapter->crc_enable = true;
> +	} else {
> +		idpf_dev_ops_init(adapter);
> +	}
> +
> +	return 0;
> +}

Hi Pavan,

I think that in Kernel Networking code the usual use cases
of goto labels are: for error handling; and, optimisation,
f.e. in the datapath.

I don't think this code falls into either category.
So I suggest implementing it without gotos.

Thanks!

...

Re: [PATCH net-next v1] idpf: add support for IDPF PCI programming interface

[Chittim, Madhu]

On 8/28/2025 3:40 AM, Simon Horman wrote:
> On Tue, Aug 26, 2025 at 10:28:45AM -0700, Pavan Kumar Linga wrote:
>> At present IDPF supports only 0x1452 and 0x145C as PF and VF device IDs
>> on our current generation hardware. Future hardware exposes a new set of
>> device IDs for each generation. To avoid adding a new device ID for each
>> generation and to make the driver forward and backward compatible,
>> make use of the IDPF PCI programming interface to load the driver.
>>
>> Write and read the VF_ARQBAL mailbox register to find if the current
>> device is a PF or a VF.
>>
>> PCI SIG allocated a new programming interface for the IDPF compliant
>> ethernet network controller devices. It can be found at:
>> https://members.pcisig.com/wg/PCI-SIG/document/20113
>> with the document titled as 'PCI Code and ID Assignment Revision 1.16'
>> or any latest revisions.
>>
>> Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
>> Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
>> Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
> 
> ...
> 
>> diff --git a/drivers/net/ethernet/intel/idpf/idpf_main.c b/drivers/net/ethernet/intel/idpf/idpf_main.c
>> index 8c46481d2e1f..b161715e1168 100644
>> --- a/drivers/net/ethernet/intel/idpf/idpf_main.c
>> +++ b/drivers/net/ethernet/intel/idpf/idpf_main.c
>> @@ -7,11 +7,57 @@
>>   
>>   #define DRV_SUMMARY	"Intel(R) Infrastructure Data Path Function Linux Driver"
>>   
>> +#define IDPF_NETWORK_ETHERNET_PROGIF				0x01
>> +#define IDPF_CLASS_NETWORK_ETHERNET_PROGIF			\
>> +	(PCI_CLASS_NETWORK_ETHERNET << 8 | IDPF_NETWORK_ETHERNET_PROGIF)
>> +
>>   MODULE_DESCRIPTION(DRV_SUMMARY);
>>   MODULE_IMPORT_NS("LIBETH");
>>   MODULE_IMPORT_NS("LIBETH_XDP");
>>   MODULE_LICENSE("GPL");
>>   
>> +/**
>> + * idpf_dev_init - Initialize device specific parameters
>> + * @adapter: adapter to initialize
>> + * @ent: entry in idpf_pci_tbl
>> + *
>> + * Return: %0 on success, -%errno on failure.
>> + */
>> +static int idpf_dev_init(struct idpf_adapter *adapter,
>> +			 const struct pci_device_id *ent)
>> +{
>> +	u8 is_vf = 0;
>> +	int err;
>> +
>> +	switch (ent->device) {
>> +	case IDPF_DEV_ID_PF:
>> +		goto dev_ops_init;
>> +	case IDPF_DEV_ID_VF:
>> +		is_vf = 1;
>> +		goto dev_ops_init;
>> +	default:
>> +		if (ent->class == IDPF_CLASS_NETWORK_ETHERNET_PROGIF)
>> +			goto check_vf;
>> +
>> +		return -ENODEV;
>> +	}
>> +
>> +check_vf:
>> +	err = idpf_is_vf_device(adapter->pdev, &is_vf);
>> +	if (err)
>> +		return err;
>> +
>> +dev_ops_init:
>> +	if (is_vf) {
>> +		idpf_vf_dev_ops_init(adapter);
>> +		adapter->crc_enable = true;
>> +	} else {
>> +		idpf_dev_ops_init(adapter);
>> +	}
>> +
>> +	return 0;
>> +}
> 
> Hi Pavan,
> 
> I think that in Kernel Networking code the usual use cases
> of goto labels are: for error handling; and, optimisation,
> f.e. in the datapath.
> 
> I don't think this code falls into either category.
> So I suggest implementing it without gotos.
> 
> Thanks!
> 
Pavan is on Vacation, will fix it in v3. Thank you> ...