[PATCH v3 00/10] ARM: tegra: Add PCIe device tree support

On 09/07/2012 06:04 PM, Russell King - ARM Linux wrote:

On Fri, Sep 07, 2012 at 05:34:35PM -0600, Stephen Warren wrote:

quoted

I guess it's a pretty basic premise of the current PCI code that all the
PCI scanning happens well before any device drivers are registered,
which in turn means that device_add() doesn't trigger the device's
probe() until much later, after all the fixups and resource assignments
are done?

Are you saying that the PCI layer is again screwed up after all my
hard work several years ago to ensure that PCI devices are properly
setup _before_ they're made available to the PCI drivers then?  That
was around the time I was looking at Cardbus stuff, ensuring that that
worked with the same guarantees.

Not amused.

What is wrong with the "probe devices, apply fixups, setup resources,
apply more fixups, publish" process that it's had to be yet again
broken?

I must admit, I'm having a hard time finding when the code worked like
that; ARM's bios32.c:pcibios_init_hw() seems to have always called
pci_scan_root_bus(), or ops function hw->scan(), which at least in the 1
PCIe controller driver I looked at, in turn always called either
pci_scan_root_bus() or another similar function that I believe always
called pci_bus_add_devices(), which is before pci_common_init() could
assign the resources. Maybe I'm just looking at the wrong PCIe
controller driver, or not looking back far enough in git history (or
pre-git)? If you could point out when it was working as you describe
(which sounds reasonable), I'd be interested in tracing the history from
there to see when/why it changed.