Re: [PATCH] PCI/AER: Remove deprecated documentation for pcie_enable_pcie_error_reporting()

[Stefan Roese <sr@denx.de>]

On 2/14/23 18:37, Dave Jiang wrote:
> 
> 
> On 2/14/23 10:28 AM, Bjorn Helgaas wrote:
>> [+cc Stefan, Sathy, Jonathan]
>>
>> On Tue, Feb 14, 2023 at 09:48:55AM -0700, Dave Jiang wrote:
>>> With commit [1] upstream that enables AER reporting by default for 
>>> all PCIe
>>> devices, the documentation for pcie_enable_pcie_error_reporting() is no
>>> longer necessary. Remove references to the helper function.
>>>
>>> [1]: commit f26e58bf6f54 ("PCI/AER: Enable error reporting when AER 
>>> is native")
>>>
>>> Suggested-by: Dan Williams <dan.j.williams@intel.com>
>>> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
>>
>> Thanks!  I'll attach my work-in-progress patch from yesterday for your
>> comments.  I think we can go even a little further because I don't
>> think we need to encourage drivers to configure AER registers (if they
>> do, they almost certainly don't pay attention to ownership via _OSC),
>> and if they don't use pci_enable_pcie_error_reporting(), they
>> shouldn't use pci_disable_pcie_error_reporting() either.
>>
>>> ---
>>>   Documentation/PCI/pcieaer-howto.rst |   18 ------------------
>>>   1 file changed, 18 deletions(-)
>>>
>>> diff --git a/Documentation/PCI/pcieaer-howto.rst 
>>> b/Documentation/PCI/pcieaer-howto.rst
>>> index 0b36b9ebfa4b..a82802795a06 100644
>>> --- a/Documentation/PCI/pcieaer-howto.rst
>>> +++ b/Documentation/PCI/pcieaer-howto.rst
>>> @@ -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
>>>   -----------------
>>> @@ -214,15 +205,6 @@ 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);
>>
>>
>> commit d7b36abe72db ("Remove AER Capability configuration")
>> Author: Bjorn Helgaas <bhelgaas@google.com>
>> Date:   Mon Feb 13 11:53:42 2023 -0600
>>
>>      Remove AER Capability configuration
> 
> The changes LGTM.
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>

Reviewed-by: Stefan Roese <sr@denx.de>

Thanks,
Stefan

> 
>>
>> 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
>>   ========================

Viele Grüße,
Stefan Roese

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