dm: pci: Support bridge device configuration correctly
Commit aec241df "dm: pci: Use the correct hose when configuring devices" was an attempt to fix pci bridge device configuration, but unfortunately that does not work 100%. In pciauto_config_devices(), the fix tried to call pciauto_config_device() with a ctlr_hose which is supposed to be the root controller hose, however when walking through a pci topology with 2 or more pci bridges this logic simply fails. The call chain is: pciauto_config_devices()->pciauto_config_device() ->dm_pci_hose_probe_bus(). Here the call to dm_pci_hose_probe_bus() does not make any sense as the given hose is not the bridge device's hose, instead it is either the root controller's hose (case#1: if it is the 2nd pci bridge), or the bridge's parent bridge's hose (case#2: if it is the 3rd pci bridge). In both cases the logic is wrong. For example, for failing case#1 if the bridge device to config has the same devfn as one of the devices under the root controller, the call to pci_bus_find_devfn() will return the udevice of that pci device under the root controller as the bus, but this is wrong as the udevice is not a bus which does not contain all the necessary bits associated with the udevice which causes further failures. To correctly support pci bridge device configuration, we should still call pciauto_config_device() with the pci bridge's hose directly. In order to access valid pci region information, we need to refer to the root controller simply by a call to pci_bus_to_hose(0) and get the region information there in the pciauto_prescan_setup_bridge(), pciauto_postscan_setup_bridge() and pciauto_config_device(). Signed-off-by: NBin Meng <bmeng.cn@gmail.com>
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