[PATCH v3 18/28] of: property: Allow fw_devlink device-tree on x86 when PCI device-tree node creation is enabled

[Rob Herring]

On Fri, Jun 27, 2025 at 11:33 AM Andy Shevchenko
<andriy.shevchenko at linux.intel.com> wrote:
>
> On Fri, Jun 27, 2025 at 11:22:45AM -0500, Rob Herring wrote:
> > On Fri, Jun 13, 2025 at 03:47:58PM +0200, Herve Codina wrote:
>
> ...
>
> > > -   if (IS_ENABLED(CONFIG_X86))
> > > +   if (IS_ENABLED(CONFIG_X86) && !IS_ENABLED(CONFIG_PCI_DYNAMIC_OF_NODES))
> >
> > I really want CONFIG_PCI_DYNAMIC_OF_NODES to go away at some point, not
> > add more users.
> >
> > I think this should instead check for specific platforms not with
> > kconfig symbols but DT properties. For ce4100, you can just check the
> > root compatible string. For OLPC, there isn't a root compatible (in the
> > DT I have). You could check for /architecture == OLPC instead. There's
> > some virtualization guests using DT now too. I would think their DT's
> > are simple enough to avoid any fw_devlink issues.
>
> I don't think this is good approach. The above check is more reliable in my
> opinion.

I'm fine with any solution that doesn't add a
CONFIG_PCI_DYNAMIC_OF_NODES which we can't remove. Adding it was a
kick the can down the road to merge the support worry the mixed
usecase (on ACPI systems) later. It's now later.

> > Alternatively, we could perhaps make x86 fw_devlink default off
>
> For my (little) knowledge I believe this is not feasible anymore.
> Some x86 code (drivers) relies on fw_devlink nowadays. But take
> this with grain of salt, I may be way mistaken.

Doesn't the CONFIG_X86 check disable it?

Rob