From: Suneel Garapati sgarapati@marvell.com
If ARI capability is found on device, use it to update next function number in bus scan and also helps to skip unnecessary bdf scans.
Signed-off-by: Suneel Garapati sgarapati@marvell.com Reviewed-by: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com
Signed-off-by: Stefan Roese sr@denx.de ---
Changes in v1: - Change patch subject - Fixed multi-line comment style - Added CONFIG_PCI_ARID and enabled the new code optionally, so that the code size is not increased in all cases
drivers/pci/Kconfig | 9 +++++++++ drivers/pci/pci-uclass.c | 26 ++++++++++++++++++++++++++ 2 files changed, 35 insertions(+)
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 3676fa85db..bc77c23f89 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -63,6 +63,15 @@ config PCI_SRIOV if available on a PCI Physical Function device and probe for applicable drivers.
+config PCI_ARID + bool "Enable Alternate Routing-ID support for PCI" + depends on PCI || DM_PCI + default n + help + Say Y here if you want to enable Alternate Routing-ID capability + support on PCI devices. This helps to skip some devices in BDF + scan that are not present. + config PCIE_ECAM_GENERIC bool "Generic ECAM-based PCI host controller support" default n diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index 5e68a2e306..be685f9143 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -799,6 +799,7 @@ int pci_bind_bus_devices(struct udevice *bus) ulong header_type; pci_dev_t bdf, end; bool found_multi; + int ari_off; int ret;
found_multi = false; @@ -872,6 +873,31 @@ int pci_bind_bus_devices(struct udevice *bus) pplat->vendor = vendor; pplat->device = device; pplat->class = class; + + if (IS_ENABLED(CONFIG_PCI_ARID)) { + ari_off = dm_pci_find_ext_capability(dev, + PCI_EXT_CAP_ID_ARI); + if (ari_off) { + u16 ari_cap; + + /* + * Read Next Function number in ARI Cap + * Register + */ + dm_pci_read_config16(dev, ari_off + 4, + &ari_cap); + /* + * Update next scan on this function number, + * subtract 1 in BDF to satisfy loop increment. + */ + if (ari_cap & 0xff00) { + bdf = PCI_BDF(PCI_BUS(bdf), + PCI_DEV(ari_cap), + PCI_FUNC(ari_cap)); + bdf = bdf - 0x100; + } + } + } }
return 0;