Re: [PATCH 00/24] PCI: Bridge window selection improvements

[Geert Uytterhoeven]

CC Greg

On Thu, 28 Aug 2025 at 00:36, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> On Fri, Aug 22, 2025 at 05:55:41PM +0300, Ilpo Järvinen wrote:
> > This series is based on top of the three resource fitting and
> > assignment algorithm fixes (v3).
> >
> > PCI resource fitting and assignment code needs to find the bridge
> > window a resource belongs to in multiple places, yet, no common
> > function for that exists. Thus, each site has its own version of
> > the decision, each with their own corner cases, misbehaviors, and
> > some resulting in complex interfaces between internal functions.
> > ...
>
> > I've tried to look out for any trouble that code under arch/ could
> > cause after the flags start to behave differently and therefore ended
> > up consolidating arch/ code to use pci_enable_resources(). My
> > impression is that strictly speaking only the MIPS code would break
> > similar to PCI core's copy of pci_enable_resources(), the others were
> > much more lax in checking so they'd likely keep working but
> > consolidation seemed still the best approach there as the enable checks
> > seemed diverging for no apparent reason.
> > ...
>
> >   m68k/PCI: Use pci_enable_resources() in pcibios_enable_device()
> >   sparc/PCI: Remove pcibios_enable_device() as they do nothing extra
> >   MIPS: PCI: Use pci_enable_resources()
> > ...
>
> >  arch/m68k/kernel/pcibios.c   |  39 +-
> >  arch/mips/pci/pci-legacy.c   |  38 +-
> >  arch/sparc/kernel/leon_pci.c |  27 --
> >  arch/sparc/kernel/pci.c      |  27 --
> >  arch/sparc/kernel/pcic.c     |  27 --
> > ...
>
> I love the fact that you're doing so much cleanup.  Thanks for all the
> work in this!
>
> Obviously all this code is quite sensitive, so I put it on
> pci/resource to get more exposure in -next.  If it turns out that we
> trip over things or just don't feel comfortable yet for v6.18, we can
> always defer this part until the next cycle.
>
> I will also watch for acks from the m68k, mips, and sparc maintainers
> for those pieces.