In the process of converting .scan_bus() callbacks to .add_bus(), the ks_pcie_v3_65_scan_bus() function was changed to ks_pcie_v3_65_add_bus(). The .scan_bus() method belonged to ks_pcie_host_ops which was specific to controller version 3.65a, while the .add_bus() method had been added to ks_pcie_ops which is shared between the controller versions 3.65a and 4.90a. Neither the older ks_pcie_v3_65_scan_bus() method, nor the newer ks_pcie_v3_65_add_bus() method are applicable to the controller version 4.90a which is present in AM654x SoCs. Thus, as a fix, move the contents of "ks_pcie_v3_65_add_bus()" to the .host_init callback "ks_pcie_host_init()" and execute it only for non AM654x SoC devices which have the v3.65a DWC PCIe IP Controllers. Fixes: 6ab15b5e7057 ("PCI: dwc: keystone: Convert .scan_bus() callback to use add_bus") Suggested-by: Serge Semin <fancer.lancer@xxxxxxxxx> Suggested-by: Bjorn Helgaas <helgaas@xxxxxxxxxx> Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx> --- Hello, This patch is based on linux-next tagged next-20240325. This patch is technically the next version for the v3 patch at: https://patchwork.kernel.org/project/linux-pci/patch/20231019081330.2975470-1-s-vadapalli@xxxxxx/ but the implementation is based on the RFC patch at: https://patchwork.kernel.org/project/linux-pci/patch/20231027084159.4166188-1-s-vadapalli@xxxxxx/ Since the RFC patch mentioned above fixes the same issue being fixed by the v3 patch, I have dropped the v3 patch and am using the RFC patch since it is a cleaner implementation and was discussed at: https://lore.kernel.org/r/20231019220847.GA1413474@bhelgaas/ Regards, Siddharth. drivers/pci/controller/dwc/pci-keystone.c | 51 ++++++++--------------- 1 file changed, 17 insertions(+), 34 deletions(-) diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c index 844de4418724..f45bdeac520a 100644 --- a/drivers/pci/controller/dwc/pci-keystone.c +++ b/drivers/pci/controller/dwc/pci-keystone.c @@ -445,44 +445,10 @@ static struct pci_ops ks_child_pcie_ops = { .write = pci_generic_config_write, }; -/** - * ks_pcie_v3_65_add_bus() - keystone add_bus post initialization - * @bus: A pointer to the PCI bus structure. - * - * This sets BAR0 to enable inbound access for MSI_IRQ register - */ -static int ks_pcie_v3_65_add_bus(struct pci_bus *bus) -{ - struct dw_pcie_rp *pp = bus->sysdata; - struct dw_pcie *pci = to_dw_pcie_from_pp(pp); - struct keystone_pcie *ks_pcie = to_keystone_pcie(pci); - - if (!pci_is_root_bus(bus)) - return 0; - - /* Configure and set up BAR0 */ - ks_pcie_set_dbi_mode(ks_pcie); - - /* Enable BAR0 */ - dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 1); - dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, SZ_4K - 1); - - ks_pcie_clear_dbi_mode(ks_pcie); - - /* - * For BAR0, just setting bus address for inbound writes (MSI) should - * be sufficient. Use physical address to avoid any conflicts. - */ - dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, ks_pcie->app.start); - - return 0; -} - static struct pci_ops ks_pcie_ops = { .map_bus = dw_pcie_own_conf_map_bus, .read = pci_generic_config_read, .write = pci_generic_config_write, - .add_bus = ks_pcie_v3_65_add_bus, }; /** @@ -822,6 +788,23 @@ static int __init ks_pcie_host_init(struct dw_pcie_rp *pp) if (ret < 0) return ret; + if (!ks_pcie->is_am6) { + /* Configure and set up BAR0 */ + ks_pcie_set_dbi_mode(ks_pcie); + + /* Enable BAR0 */ + dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 1); + dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, SZ_4K - 1); + + ks_pcie_clear_dbi_mode(ks_pcie); + + /* + * For BAR0, just setting bus address for inbound writes (MSI) should + * be sufficient. Use physical address to avoid any conflicts. + */ + dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, ks_pcie->app.start); + } + #ifdef CONFIG_ARM /* * PCIe access errors that result into OCP errors are caught by ARM as -- 2.40.1