On Mon, Aug 22, 2016 at 11:47 PM, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > On Fri, Aug 19, 2016 at 04:24:38PM +0800, Ley Foon Tan wrote: >> Altera PCIe IP can be configured as rootport or device and they might have >> same vendor ID. It will cause the system hang issue if Altera PCIe is in >> endpoint mode and work with other PCIe rootport that from other vendors. >> So, add the rootport mode checking in link retrain fixup function. >> >> Signed-off-by: Ley Foon Tan <lftan@xxxxxxxxxx> >> --- >> v2: change to check PCIe type is PCI_EXP_TYPE_ROOT_PORT >> --- >> drivers/pci/host/pcie-altera.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/pci/host/pcie-altera.c b/drivers/pci/host/pcie-altera.c >> index 58eef99..33b6968 100644 >> --- a/drivers/pci/host/pcie-altera.c >> +++ b/drivers/pci/host/pcie-altera.c >> @@ -139,6 +139,9 @@ static void altera_pcie_retrain(struct pci_dev *dev) >> u16 linkcap, linkstat; >> struct altera_pcie *pcie = dev->bus->sysdata; >> >> + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) >> + return; >> + >> if (!altera_pcie_link_is_up(pcie)) >> return; > > Instead of making this a PCI fixup, can you make an > altera_pcie_host_init() function, call it from altera_pcie_probe(), > and do the link retrain there? Then you wouldn't need to worry about > whether this is a Root Port or an Endpoint, plus it would make the > altera driver structure more like the other drivers. > > You would call altera_pcie_host_init() before pci_scan_root_bus(), so > you wouldn't have a pci_dev yet, so you wouldn't be able to use > pcie_capability_set_word() to set the PCI_EXP_LNKCTL_RL bit. But I > assume there's some device-dependent way to access it using > cra_writel()? We can't use cra_write() to set PCI_EXP_LNKCTL_RL bit. We can use pci_bus_find_capability() and pci_bus_read_config_word() with struct pci_bus instead. But this only can be called after pci_scan_root_bus(). Found iproc_pcie_check_link() have similar implementation. Tested this method is working. Do you think it is okay? If yes, then I will send in next revision. Thanks. Regards Ley Foon -- 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
