Re: [PATCH V13 0/5] Generate device tree node for pci devices

Andy Shevchenko
2023-09-18T07:18:18Z

On Fri, Sep 15, 2023 at 07:30:08PM +0200, Herve Codina wrote:
> On Wed, 13 Sep 2023 14:17:30 +0300
> Andy Shevchenko <andriy.shevchenko@intel.com> wrote:
> > On Tue, Sep 12, 2023 at 02:12:04PM -0500, Rob Herring wrote:
> > > On Mon, Sep 11, 2023 at 3:37 PM Andy Shevchenko
> > > <andriy.shevchenko@intel.com> wrote:
> > > > On Tue, Aug 15, 2023 at 10:19:55AM -0700, Lizhi Hou wrote:

...

> > > > Can you point out to the ACPI excerpt(s) of the description of anything related
> > > > to the device(s) in question?
> > >
> > > I don't understand what you are asking for.
> >
> > Through the email thread it was mentioned that this series was tested on the
> > ACPI enabled platform, Jonathan (IIRC) asked why do we need to have a shadow
> > DT for the something that ACPI already describes. That's why I'm trying to
> > understand if it's the case. and if so, how can we improve the approach.
>
> Patches from Frank Rowand series [1] are needed to create an of_root_node if a DT
> was not provided by the firmware, bootloader, etc that run the kernel.
>
> [1]: https://lore.kernel.org/lkml/20220624034327.2542112-1-frowand.list@gmail.com/
>
> Current Lizhi's series creates nodes from the PCI host node during the PCI
> enumeration. It creates PCI-PCI bridge and PCI device nodes.
>
> I use these series on an ACPI system.
>
> I need one more missing component: the node related to the PCI host bridge
> This was the purpose of Clement's work. This work was not sent upstream yet and I
> am working on it in order to have a full tree from the of_root to the PCI device
> ie:
> of_root <-- Frank Rowand series
> + of_host_pci_bridge <-- Clement's work
> + pci_bridge <-- Current Lizhi series
> + pci_bridge <-- Current Lizhi series
> ...
> + pci_dev <-- Current Lizhi series
>
> Hope that this status helped.

Thanks for the explanation! I suppose it's better to have three series combined
into one and being sent with a better cover letter to explain all this. Also it
might make sense (in my opinion) to Cc Jonathan (I did it here). Sorry, Jonathan,
if you are not wanting this.

--
With Best Regards,
Andy Shevchenko