Re: [PATCH v9 7/7] PCI/DPC: Enumerate the devices after DPC trigger event
From: Randy Dunlap
Date: Thu Feb 22 2018 - 14:23:55 EST
On 02/21/2018 11:46 PM, Oza Pawandeep wrote:
> Implement error_resume callback in DPC so, after DPC trigger event
> enumerates the devices beneath.
>
> Signed-off-by: Oza Pawandeep <poza@xxxxxxxxxxxxxx>
>
> diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c
> index fce4518..59c01c7 100644
> --- a/drivers/pci/pcie/pcie-dpc.c
> +++ b/drivers/pci/pcie/pcie-dpc.c
> @@ -129,6 +129,23 @@ static void dpc_wait_link_inactive(struct dpc_dev *dpc)
> }
>
> /**
> + * dpc_error_resume - enumerate the devices beneath
> + * @dev: pointer to Root Port's pci_dev data structure
* @pdev: ...
> + *
> + * Invoked by Port Bus driver during nonfatal recovery.
> + */
> +static void dpc_error_resume(struct pci_dev *pdev)
> +{
> + bool active = true;
> +
> + if (pci_wait_for_link(pdev, active)) {
> + pci_lock_rescan_remove();
> + pci_rescan_bus(pdev->bus);
> + pci_unlock_rescan_remove();
> + }
> +}
> +
> +/**
> * dpc_reset_link - reset link DPC routine
> * @dev: pointer to Root Port's pci_dev data structure
> *
> diff --git a/drivers/pci/pcie/pcie-err.c b/drivers/pci/pcie/pcie-err.c
> index 6844347..4950f49 100644
> --- a/drivers/pci/pcie/pcie-err.c
> +++ b/drivers/pci/pcie/pcie-err.c
> @@ -256,6 +258,15 @@ static pci_ers_result_t broadcast_error_message(struct pci_dev *dev,
> result_data.result = PCI_ERS_RESULT_RECOVERED;
>
> if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
> + /* If DPC is triggered, call resume error hanlder
handler
Kernel multi-line comment style is:
/*
* Begin comment here.
* foo bar blah
*/
> + * because, at this point we can safely assume that
> + * link recovery has happened.
> + */
> + if ((severity == DPC_FATAL) &&
> + (cb == report_resume)) {
> + cb(dev, NULL);
> + return PCI_ERS_RESULT_RECOVERED;
> + }
> /*
> * If the error is reported by a bridge, we think this error
> * is related to the downstream link of the bridge, so we
thanks,
--
~Randy