Hi Sathyanarayanan, On Wed, 2020-04-22 at 15:50 -0700, Kuppuswamy, Sathyanarayanan wrote: > > On 4/20/20 2:37 PM, Jon Derrick wrote: > > The existing portdrv model prevents DPC services without either OS > > control (_OSC) granted to AER services, a Host Bridge requesting Native > > AER, or using one of the 'pcie_ports=' parameters of 'native' or > > 'dpc-native'. > > > > The DPC port service driver itself will also fail to probe if the kernel > > assumes the port is using Firmware-First AER. It's a reasonable > > expectation that a port using Firmware-First AER will also be using > > Firmware-First DPC, however if a Host Bridge requests Native DPC, the > > DPC driver should allow it and not fail to bind due to AER capability > > settings. > > > > Host Bridges which request Native DPC port services will also likely > > request Native AER, however it shouldn't be a requirement. This patch > > allows ports on those Host Bridges to have DPC port services. > > > > This will avoid the unlikely situation where the port is Firmware-First > > AER and Native DPC, and a BIOS or switch firmware preconfiguration of > > the DPC trigger could result in unhandled DPC events. > > > > Signed-off-by: Jon Derrick <jonathan.derrick@xxxxxxxxx> > > --- > > drivers/pci/pcie/dpc.c | 3 ++- > > drivers/pci/pcie/portdrv_core.c | 3 ++- > > 2 files changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c > > index 7621704..3f3106f 100644 > > --- a/drivers/pci/pcie/dpc.c > > +++ b/drivers/pci/pcie/dpc.c > > @@ -284,7 +284,8 @@ static int dpc_probe(struct pcie_device *dev) > > int status; > > u16 ctl, cap; > > > > - if (pcie_aer_get_firmware_first(pdev) && !pcie_ports_dpc_native) > > + if (pcie_aer_get_firmware_first(pdev) && !pcie_ports_dpc_native && > > + !pci_find_host_bridge(pdev->bus)->native_dpc) > Why do it in probe as well ? if host->native_dpc is not set then the > device DPC probe it self won't happen right ? Portdrv only enables the interrupt and allows the probe to occur. The probe itself will still fail if there's a mixed-mode _OSC negotiated AER & DPC, due to pcie_aer_get_firmware_first returning 1 for AER and no check for DPC. I don't know if such a platform will exist, but the kernel is already wired for 'dpc-native' so it makes sense to extend it for this.. This transform might be more readable: if (pcie_aer_get_firmware_first(pdev) && !(pcie_ports_dpc_native || hb->native_dpc)) > > return -ENOTSUPP; > > > > status = devm_request_threaded_irq(device, dev->irq, dpc_irq, > > diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c > > index 50a9522..f2139a1 100644 > > --- a/drivers/pci/pcie/portdrv_core.c > > +++ b/drivers/pci/pcie/portdrv_core.c > > @@ -256,7 +256,8 @@ static int get_port_device_capability(struct pci_dev *dev) > > */ > > if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC) && > > pci_aer_available() && > > - (pcie_ports_dpc_native || (services & PCIE_PORT_SERVICE_AER))) > > + (pcie_ports_dpc_native || host->native_dpc || > > + (services & PCIE_PORT_SERVICE_AER))) > > services |= PCIE_PORT_SERVICE_DPC; > > > > if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM || > >
