On Tue, 16 Jun 2020 11:00:32 -0700 "Kuppuswamy, Sathyanarayanan" <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: > Hi Jonathan, > > On 6/16/20 10:47 AM, Bjorn Helgaas wrote: > > [+cc Sathy] > > > > On Fri, May 22, 2020 at 01:31:33AM +0800, Jonathan Cameron wrote: > >> pci_aer_clear_device_status() currently resets the device status even when > >> firmware first handling is going on. In particular it resets it on the > >> root port. > >> > >> This has been discussed previously > >> https://lore.kernel.org/patchwork/patch/427375/. > pci_aer_clear_device_status() is only used by handle_error_source(). And > I don't think handle_error_source() is called in FF mode. Can you > give more details on this issue ? It's called in pcie_do_recovery https://elixir.bootlin.com/linux/latest/source/drivers/pci/pcie/err.c#L200 Which is called from both handle_error_source and aer_recover_work_func. indirectly called from ghes_handle_aer / ghes_do_proc This particular flow will only happen (I think) on hardware reduced ACPI systems. Jonathan > > > > I don't think this reference is really pertinent, is it? That patch > > to b2c8881da764 changes pci_cleanup_aer_uncorrect_error_status() so it > > doesn't clear PCI_ERR_UNCOR_STATUS in "firmware-first" mode. > > > > But your patch only affects PCI_EXP_DEVSTA, not PCI_ERR_UNCOR_STATUS. > > > >> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > >> --- > >> drivers/pci/pcie/aer.c | 3 +++ > >> 1 file changed, 3 insertions(+) > >> > >> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c > >> index f4274d301235..43e78b97ace6 100644 > >> --- a/drivers/pci/pcie/aer.c > >> +++ b/drivers/pci/pcie/aer.c > >> @@ -373,6 +373,9 @@ void pci_aer_clear_device_status(struct pci_dev *dev) > >> { > >> u16 sta; > >> > >> + if (pcie_aer_get_firmware_first(dev)) > >> + return; > > > > This needs to be adjusted because pcie_aer_get_firmware_first() no > > longer exists after 708b20003624 ("PCI/AER: Remove HEST/FIRMWARE_FIRST > > parsing for AER ownership"). > > > > This will use the _OSC AER ownership bit to gate clearing of the > > status bits in the PCIe capability (not the AER capability). > > > > I think that's the right thing to do, but it's certainly not obvious > > from the _OSC description in the PCI Firmware Spec r3.2. I think we > > need a pointer to the ECN that clarifies this, i.e., sec 4.5.1 of: > > > > System Firmware Intermediary (SFI) _OSC and DPC Updates ECN, Feb 24, > > 2020, affecting PCI Firmware Specification, Rev. 3.2 > > https://members.pcisig.com/wg/PCI-SIG/document/14076 > > > >> pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &sta); > >> pcie_capability_write_word(dev, PCI_EXP_DEVSTA, sta); > >> } > >> -- > >> 2.19.1 > >> >
