On Wed, 29 Apr 2026, Ilpo Järvinen wrote:
> pci_resource_alignment() does not consider bridge windows special,
> yet their alignment is subject to different requirements from BAR
> alignment.
>
> Add lower bound to bridge window alignment to help callers out to
> always have large enough alignment.
>
> Signed-off-by: Ilpo Järvinen <[email protected]>
Hi Bjorn,
Could you please pull this change and the subsequent one, the commits in
pci/resource:
ae09d28ecbbc ("PCI: Lower bound bridge window alignment")
cf996b886675 ("PCI: Return valid alignment for assigned resources")
The rest of the changes in this series seem okay and can proceed if you're
okay with keeping a partial series.
The reason for this request is the dev->bus vs dev->subordinate issue
sashiko mentioned in its review.
I've tried to come up with a solution to that but it has become so ugly
I have not been very happy with it. Maybe there's no other way but the
problem boils down with pci_min_window_alignment() having to be capable of
dealing two cases, each lacking one of the key pointers (bus or bridge
dev):
1) root bus without bus->self
2) bridge without a subordinate bus struct (if subordinate bus' alloc
failed)
Only way to solve that I could think of is passing both the bus and the
bridge device to pci_min_window_alignment() and the related arch side
function pcibios_window_alignment(). The ugliest parts then involve
getting a bus pointer compatible with both of those cases, like this:
struct pci_controller *phb = pci_bus_to_host(bus ? bus : bridge->bus);
But it's too late in the cycle now to try even that, IMO, so better to
wait to the next cycle.
--
i.
