On Tue, Sep 22, 2020 at 02:38:54PM -0700, Sean V Kelley wrote:
> From: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
>
> Attempt to do function level reset for an RCiEP associated with an
> RCEC device on fatal error.
>
> Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
> ---
> drivers/pci/pcie/err.c | 31 ++++++++++++++++++++++---------
> 1 file changed, 22 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
> index e575fa6cee63..5380ecc41506 100644
> --- a/drivers/pci/pcie/err.c
> +++ b/drivers/pci/pcie/err.c
> @@ -169,6 +169,17 @@ static void pci_bridge_walk(struct pci_dev *bridge, int (*cb)(struct pci_dev *,
> cb(bridge, userdata);
> }
>
> +static pci_ers_result_t flr_on_rciep(struct pci_dev *dev)
> +{
> + if (!pcie_has_flr(dev))
> + return PCI_ERS_RESULT_NONE;
> +
> + if (pcie_flr(dev))
> + return PCI_ERS_RESULT_DISCONNECT;
> +
> + return PCI_ERS_RESULT_RECOVERED;
> +}
Either we reset the device or we didn't; there is no third option.
If I read it correctly, nothing in pcie_do_recovery() cares about the
difference between PCI_ERS_RESULT_NONE and PCI_ERS_RESULT_DISCONNECT.
The status does get returned, but only edr_handle_event() looks at it,
and it doesn't care about the difference either.
So I think this should just return PCI_ERS_RESULT_RECOVERED or
PCI_ERS_RESULT_DISCONNECT.
> pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
> pci_channel_state_t state,
> pci_ers_result_t (*reset_subordinate_devices)(struct pci_dev *pdev))
> @@ -195,15 +206,17 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
> if (state == pci_channel_io_frozen) {
> pci_bridge_walk(bridge, report_frozen_detected, &status);
> if (type == PCI_EXP_TYPE_RC_END) {
> - pci_warn(dev, "link reset not possible for RCiEP\n");
> - status = PCI_ERS_RESULT_NONE;
> - goto failed;
> - }
> -
> - status = reset_subordinate_devices(bridge);
> - if (status != PCI_ERS_RESULT_RECOVERED) {
> - pci_warn(dev, "subordinate device reset failed\n");
> - goto failed;
> + status = flr_on_rciep(dev);
> + if (status != PCI_ERS_RESULT_RECOVERED) {
> + pci_warn(dev, "function level reset failed\n");
> + goto failed;
> + }
> + } else {
> + status = reset_subordinate_devices(bridge);
> + if (status != PCI_ERS_RESULT_RECOVERED) {
> + pci_warn(dev, "subordinate device reset failed\n");
> + goto failed;
> + }
> }
> } else {
> pci_bridge_walk(bridge, report_normal_detected, &status);
> --
> 2.28.0
>
