Re: [PATCH v2] PCI/EDR: Clear PCIe Device Status errors after EDR error recovery

[Sathyanarayanan Kuppuswamy]

On 4/7/23 2:52 PM, Bjorn Helgaas wrote:
> On Fri, Apr 07, 2023 at 04:51:44PM -0500, Bjorn Helgaas wrote:
>> I'll post a follow-up patch to add a couple comments there,
>> too.
> 
> Comments I propose:
> 
> 
>     PCI/EDR: Add edr_handle_event() comments
>     
>     EDR documentation is a bit sketchy.  Add a couple comments to
>     edr_handle_event() about the devices involved.
>     
>     Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> 
> diff --git a/drivers/pci/pcie/edr.c b/drivers/pci/pcie/edr.c
> index 87734e4c3c20..135ddb53661c 100644
> --- a/drivers/pci/pcie/edr.c
> +++ b/drivers/pci/pcie/edr.c
> @@ -151,9 +151,17 @@ static void edr_handle_event(acpi_handle handle, u32 event, void *data)
>  	if (event != ACPI_NOTIFY_DISCONNECT_RECOVER)
>  		return;
>  
> +	/*
> +	 * pdev itself is still present, but one or more of its child
> +	 * devices have been disconnected (ACPI v6.3, sec 5.6.6).
> +	 */

Maybe add info that pdev can be a root port or a downstream port?

>  	pci_info(pdev, "EDR event received\n");
>  
> -	/* Locate the port which issued EDR event */
> +	/*
> +	 * Locate the port that experienced the containment event.  pdev
> +	 * may be that port or a parent of it (PCI Firmware r3.3, sec
> +	 * 4.6.13).
> +	 */
>  	edev = acpi_dpc_port_get(pdev);
>  	if (!edev) {
>  		pci_err(pdev, "Firmware failed to locate DPC port\n");


Otherwise, looks good to me.

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

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer