On Tue, 16 Jun 2020 12:47:31 -0500 Bjorn Helgaas <helgaas@xxxxxxxxxx> 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/. > > 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. I'll be honest I've mostly forgotten my reasoning behind including that reference. Might have been as simple as I got lost in the renames. I'll drop the reference. > > > 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 Thanks. I'll add that (though can't check the document currently for reasons you can probably figure out *sigh*) Note this patch is rather tangential to patch 2 which is the one I really need feedback on. Whilst this appeared to be wrong it is 'mostly harmless'. > > > pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &sta); > > pcie_capability_write_word(dev, PCI_EXP_DEVSTA, sta); > > } > > -- > > 2.19.1 > >
