[U-Boot] [PATCH v5 7/8] board: intel: Add new slimbootloader board

[Bin Meng]

Hi Aiden,

On Wed, Jul 24, 2019 at 11:18 AM Park, Aiden <aiden.park at intel.com> wrote:
>
> Hi Andy,
>
> > -----Original Message-----
> > From: Andy Shevchenko [mailto:andy.shevchenko at gmail.com]
> > Sent: Tuesday, July 23, 2019 5:27 AM
> > To: Bin Meng <bmeng.cn at gmail.com>
> > Cc: Park, Aiden <aiden.park at intel.com>; U-Boot Mailing List <u-
> > boot at lists.denx.de>; Simon Glass <sjg at chromium.org>
> > Subject: Re: [PATCH v5 7/8] board: intel: Add new slimbootloader board
> >
> > On Tue, Jul 23, 2019 at 9:15 AM Bin Meng <bmeng.cn at gmail.com> wrote:
> > > On Mon, Jul 22, 2019 at 11:49 PM Andy Shevchenko
> > > <andy.shevchenko at gmail.com> wrote:
> > > > On Wed, Jul 17, 2019 at 7:42 AM Park, Aiden <aiden.park at intel.com> wrote:
> >
> > > > >  board/intel/slimbootloader/README           | 133 ++++++++++++++++++++
> > > >
> > > > Shouldn't become reST one?
> > >
> > > I think this will need be converted to reST after my doc series are applied.
> >
> > I had an impression that reST conversion is targeting 2019.10. It means in your
> > branch you will have it applied earlier.
> >
> Let me change this to reST if necessary.
> Hi Bin, do you want me to change this one to reST or later? Let me know.

I have no preference. You can either convert to reST later, or rebase
on top of this series to get it converted to reST now:
http://patchwork.ozlabs.org/project/uboot/list/?series=120139

>
> > > > > +int board_early_init_r(void)
> > > > > +{
> > > > > +       /*
> > > > > +        * Make sure PCI bus is enumerated so that peripherals on the PCI bus
> > > > > +        * can be discovered by their drivers
> > > > > +        */
> > > > > +       pci_init();
> > > >
> > > > I'm not sure this is how U-Boot is designed with DM.
> > > > At least my expectations that bus gets initialized followed by the
> > > > certain driver in a lazy way.
> > > > Isn't it the case? Bin?
> > >
> > > For most x86 board, yes, PCI gets enumerated automatically if some PCI
> > > APIs are called in the early initialization codes: eg: pci_{read,
> > > write}_config().
> > >
> > > But for boards like coreboot/slimbootloader, if there is no touch to
> > > any PCI config register on that board in the early phase, PCI bus
> > > remains not probed.
> >
> > Thanks for explanation!
> > Perhaps this needs a comment in the code.
> >
> Thanks Bin for your explanation. Slim Bootloader have done PCI config space setup
> and PCI device enumeration in Slim Bootloader stages.
>

Yes, and we should not re-program registers like BARs in U-Boot to
avoid mismatch, so that's why in coreboot/slimbootloader defconfig we
have:
# CONFIG_PCI_PNP is not set

Regards,
Bin