Re: [PATCH v6 1/3] PCI/AER: Factor out interrupt toggling into helpers

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, May 12, 2023 at 08:00:12AM +0800, Kai-Heng Feng wrote:
> There are many places that enable and disable AER interrupt, so move
> them into helpers.
> 
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

I applied this patch (only 1/3) to pci/aer for v6.7.

I'm not clear on the others yet, so let's look at those again after
v6.7-rc1.  It seemed like there's still a question about disabling
interrupts when we're going to D3hot.

>  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;
> -- 
> 2.34.1
>