Re: [PATCH v3 2/4] PCI/AER: Factor out interrupt toggling into helpers

[Sathyanarayanan Kuppuswamy]

On 4/20/23 5:59 AM, Kai-Heng Feng wrote:
> There are many places that enable and disable AER interrput, so move
> them into helpers.

Add "No functional changes intended"

> 
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---

Looks good to me.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

> v3:
>  - Correct subject.
> 
> v2:
>  - New patch.
> 
>  drivers/pci/pcie/aer.c | 45 +++++++++++++++++++++++++-----------------
>  1 file changed, 27 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index f6c24ded134c..1420e1f27105 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -1227,6 +1227,28 @@ static irqreturn_t aer_irq(int irq, void *context)
>  	return IRQ_WAKE_THREAD;
>  }
>  
> +static void aer_enable_irq(struct pci_dev *pdev)
> +{
> +	int aer = pdev->aer_cap;
> +	u32 reg32;
> +
> +	/* Enable Root Port's interrupt in response to error messages */
> +	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> +	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
> +	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
> +}
> +
> +static void aer_disable_irq(struct pci_dev *pdev)
> +{
> +	int aer = pdev->aer_cap;
> +	u32 reg32;
> +
> +	/* Disable Root's interrupt in response to error messages */
> +	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> +	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
> +	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
> +}
> +
>  /**
>   * aer_enable_rootport - enable Root Port's interrupts when receiving messages
>   * @rpc: pointer to a Root Port data structure
> @@ -1256,10 +1278,7 @@ static void aer_enable_rootport(struct aer_rpc *rpc)
>  	pci_read_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, &reg32);
>  	pci_write_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, reg32);
>  
> -	/* Enable Root Port's interrupt in response to error messages */
> -	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> -	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
> -	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
> +	aer_enable_irq(pdev);
>  }
>  
>  /**
> @@ -1274,10 +1293,7 @@ static void aer_disable_rootport(struct aer_rpc *rpc)
>  	int aer = pdev->aer_cap;
>  	u32 reg32;
>  
> -	/* Disable Root's interrupt in response to error messages */
> -	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> -	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
> -	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
> +	aer_disable_irq(pdev);
>  
>  	/* Clear Root's error status reg */
>  	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
> @@ -1372,12 +1388,8 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
>  	 */
>  	aer = root ? root->aer_cap : 0;
>  
> -	if ((host->native_aer || pcie_ports_native) && aer) {
> -		/* Disable Root's interrupt in response to error messages */
> -		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> -		reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
> -		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
> -	}
> +	if ((host->native_aer || pcie_ports_native) && aer)
> +		aer_disable_irq(root);
>  
>  	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {
>  		rc = pcie_reset_flr(dev, PCI_RESET_DO_RESET);
> @@ -1396,10 +1408,7 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
>  		pci_read_config_dword(root, aer + PCI_ERR_ROOT_STATUS, &reg32);
>  		pci_write_config_dword(root, aer + PCI_ERR_ROOT_STATUS, reg32);
>  
> -		/* Enable Root Port's interrupt in response to error messages */
> -		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
> -		reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
> -		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
> +		aer_enable_irq(root);
>  	}
>  
>  	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer