On Oct 7, 2010, at 7:30 AM, Eran Liberty wrote: > Dear Penguins, > > SHORT: > There is a BUG in the current code design / Freescale P2020/85xx PCIe design that prevent it from registering to the PCIe AER... or that I have missed something :) .. > > LESS SHORT: > I am in the process of a Freescale P2020 based board bring up. P2020 is basically two 85xx processors and their peripherals share most features. > > PCIe has a very extensive error reporting section and the Kernel already has a very nice looking Advanced Error Reporting driver. > > I encounter difficulties trying to connect the P2020/85xx PCIe device to this AER service driver. > > My technical findings follows: > > - pcie_portdrv_probe() will be called for every BRIDGE class PCI device. P2020 PCIe is a PCI-PCI BRIDGE class so no problem here. - The code will continue to check that we have PCI_CAP_ID_EXP capability, which we have and continue to pcie_port_device_register(). > - Now ,the function pcie_port_device_register() will FAIL. It will fail because it will call assign_interrupt_mode(), return with PCIE_PORT_NO_IRQ, and giveup with a reasonable remark in the code > "/* > * Don't use service devices that require interrupts if there is > * no way to generate them. > */" > > So now the question is why calling assign_interrupt_mode() with the P2020 PCIe ROOT device return empty? Well... > - First assign_interrupt_mode() will test for PCIE_PORT_MSIX_MODE. Freescale PCIe does not support this... > - Second attampt is made to discover PCIE_PORT_MSI_MODE, which Freescale should support but the PCIe PCI_CAP_ID_MSI capability is published on the device side of the bridge and NOT on the PCIe ROOT device, which is the one probed and thus fails. > - Last it attempts to look at "dev->pin" in order to set PCIE_PORT_INTx_MODE. On top of being the less recommended way (the old way), The Freescale PCIE ROOT device pin is not set anywhere. > > Failing all those the probe fails and the AER service is not activated for the PCIE device. > > QUESTION: > 1. What am I missing? > 2. Has anyone enabled the AER PCIe service for P2020/MPC85xx? > 3. Should the PCIe ROOT end report MSI capabilities or should the device end report itself as bridge ??? > > -- Liberty Do you have some code that enables AER on P2020. If so it might be easier to see what's going on. - k -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
