Hi,
On 6/9/23 3:24 PM, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>
> Since f26e58bf6f54 ("PCI/AER: Enable error reporting when AER is native"),
> the PCI core enables PCIe device error reporting for all devices during
> enumeration, so drivers don't need to do it.
>
> Remove the recommendation for drivers to configure AER and call
> pci_enable_pcie_error_reporting() themselves.
>
> Also remove the suggestion that drivers may change AER mask and severity
> registers. Ownership of these registers is negotiated between the OS and
> platform firmware. If firmware owns these registers, the OS must not
> change them.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> Reviewed-by: Stefan Roese <sr@xxxxxxx>
> ---
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> Documentation/PCI/pcieaer-howto.rst | 56 ++---------------------------
> 1 file changed, 2 insertions(+), 54 deletions(-)
>
> diff --git a/Documentation/PCI/pcieaer-howto.rst b/Documentation/PCI/pcieaer-howto.rst
> index 0b36b9ebfa4b..c98a229ea9f5 100644
> --- a/Documentation/PCI/pcieaer-howto.rst
> +++ b/Documentation/PCI/pcieaer-howto.rst
> @@ -96,8 +96,8 @@ Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats
> Developer Guide
> ===============
>
> -To enable AER aware support requires a software driver to configure
> -the AER capability structure within its device and to provide callbacks.
> +To enable AER aware support requires a software driver to provide
> +callbacks.
>
> To support AER better, developers need understand how AER does work
> firstly.
> @@ -135,15 +135,6 @@ hierarchy and links. These errors do not include any device specific
> errors because device specific errors will still get sent directly to
> the device driver.
>
> -Configure the AER capability structure
> ---------------------------------------
> -
> -AER aware drivers of PCI Express component need change the device
> -control registers to enable AER. They also could change AER registers,
> -including mask and severity registers. Helper function
> -pci_enable_pcie_error_reporting could be used to enable AER. See
> -section 3.3.
> -
> Provide callbacks
> -----------------
>
> @@ -212,31 +203,6 @@ to reset the link. If error_detected returns PCI_ERS_RESULT_CAN_RECOVER
> and reset_link returns PCI_ERS_RESULT_RECOVERED, the error handling goes
> to mmio_enabled.
>
> -helper functions
> -----------------
> -::
> -
> - int pci_enable_pcie_error_reporting(struct pci_dev *dev);
> -
> -pci_enable_pcie_error_reporting enables the device to send error
> -messages to root port when an error is detected. Note that devices
> -don't enable the error reporting by default, so device drivers need
> -call this function to enable it.
> -
> -::
> -
> - int pci_disable_pcie_error_reporting(struct pci_dev *dev);
> -
> -pci_disable_pcie_error_reporting disables the device to send error
> -messages to root port when an error is detected.
> -
> -::
> -
> - int pci_aer_clear_nonfatal_status(struct pci_dev *dev);`
> -
> -pci_aer_clear_nonfatal_status clears non-fatal errors in the uncorrectable
> -error status register.
> -
> Frequent Asked Questions
> ------------------------
>
> @@ -257,24 +223,6 @@ A:
> Fatal error recovery will fail if the errors are reported by the
> upstream ports who are attached by the service driver.
>
> -Q:
> - How does this infrastructure deal with driver that is not PCI
> - Express aware?
> -
> -A:
> - This infrastructure calls the error callback functions of the
> - driver when an error happens. But if the driver is not aware of
> - PCI Express, the device might not report its own errors to root
> - port.
> -
> -Q:
> - What modifications will that driver need to make it compatible
> - with the PCI Express AER Root driver?
> -
> -A:
> - It could call the helper functions to enable AER in devices and
> - cleanup uncorrectable status register. Pls. refer to section 3.3.
> -
>
> Software error injection
> ========================
--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer
