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author | Bin Meng <bmeng.cn@gmail.com> | 2015-07-19 00:20:06 +0800 |
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committer | Simon Glass <sjg@chromium.org> | 2015-07-28 10:36:24 -0600 |
commit | d11d9ef1579ed7ee58b28828a67b7e174c571fb3 (patch) | |
tree | 5803f6bc7d5090b162f1577d86a5f3d18e160d9f /arch/x86/cpu/queensbay | |
parent | 8326f136da6dc496648b8aa75d9717e2e31adad0 (diff) | |
download | u-boot-imx-d11d9ef1579ed7ee58b28828a67b7e174c571fb3.zip u-boot-imx-d11d9ef1579ed7ee58b28828a67b7e174c571fb3.tar.gz u-boot-imx-d11d9ef1579ed7ee58b28828a67b7e174c571fb3.tar.bz2 |
dm: pci: Support bridge device configuration correctly
Commit aec241d "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: Bin Meng <bmeng.cn@gmail.com>
Diffstat (limited to 'arch/x86/cpu/queensbay')
0 files changed, 0 insertions, 0 deletions