[U-Boot] [PATCH V2 1/2] pci: Support parsing PCI controller DT subnodes

[Simon Glass]

Hi Marek,

On 10 September 2018 at 01:38, Marek Vasut <marek.vasut at gmail.com> wrote:
>
> On 09/02/2018 03:07 AM, Simon Glass wrote:
> > Hi Marek,
>
> Hi,
>
> > On 1 September 2018 at 16:45, Marek Vasut <marek.vasut at gmail.com> wrote:
> >>
> >> On 09/01/2018 11:50 PM, Simon Glass wrote:
> >>> Hi Marek,
> >>>
> >>> On 30 August 2018 at 07:42, Marek Vasut <marek.vasut at gmail.com> wrote:
> >>>> On 08/30/2018 03:32 PM, Bin Meng wrote:
> >>>>> Hi Marek,
> >>>>>
> >>>>> On Thu, Aug 30, 2018 at 1:07 AM Marek Vasut <marek.vasut at gmail.com> wrote:
> >>>>>>
> >>>>>> On 08/29/2018 05:15 PM, Bin Meng wrote:
> >>>>>>> +Simon
> >>>>>>>
> >>>>>>> Hi Marek,
> >>>>>>>
> >>>>>>> On Wed, Aug 29, 2018 at 10:22 PM Marek Vasut <marek.vasut at gmail.com> wrote:
> >>>>>>>>
> >>>>>>>> On 08/24/2018 08:27 PM, Marek Vasut wrote:
> >>>>>>>>> The PCI controller can have DT subnodes describing extra properties
> >>>>>>>>> of particular PCI devices, ie. a PHY attached to an EHCI controller
> >>>>>>>>> on a PCI bus. This patch parses those DT subnodes and assigns a node
> >>>>>>>>> to the PCI device instance, so that the driver can extract details
> >>>>>>>>> from that node and ie. configure the PHY using the PHY subsystem.
> >>>>>>>>>
> >>>>>>>>> Signed-off-by: Marek Vasut <marek.vasut+renesas at gmail.com>
> >>>>>>>>> Cc: Simon Glass <sjg at chromium.org>
> >>>>>>>>> Cc: Tom Rini <trini at konsulko.com>
> >>>>>>>>
> >>>>>>>> Well, bump ?
> >>>>>>>>
> >>>>>>>> This is the only missing patch to get my hardware working properly.
> >>>>>>>
> >>>>>>> I don't think we ever had an agreement on the v1 patch. Simon had a
> >>>>>>> long email that pointed out what Linux does seems like a 'fallback' to
> >>>>>>> find a node with no compatible string.
> >>>>>>>
> >>>>>>> Back to this, if we have to go with this way, please create a test
> >>>>>>> case to cover this scenario.
> >>>>>>
> >>>>>> The fact that it works on a particular board is not tested enough?
> >>>>>> Do we need a custom, special, synthetic test ?
> >>>>>>
> >>>>>
> >>>>> I believe that's always been the requirement against the DM code
> >>>>> changes. I was requested in the past when I changed something in the
> >>>>> DM and I see other people were asked to do so. Like Alex said, it does
> >>>>> not mean this patch was not tested enough, but to ensure future
> >>>>> commits won't break this.
> >>>>
> >>>> So, do you have any suggestion how to implement this test ? It seems
> >>>> Alex posed the same question. It doesn't seem to be trivial in the
> >>>> context of sandbox.
> >>>
> >>> I suppose you need a PCI_DEVICE() declaration for sandbox, with an
> >>> associated DT node and no compatible string. Then check that you can
> >>> locate the device and that it read a DT property correctly.
> >>
> >> Is there any example of this stuff already ?
> >
> > See the bottom of swap_case.c. You might be able to add a new one of those,
> >
> > If you look at pci-controller2 in test.dts it has a device with a
> > compatible string. You could try adding a second device with no
> > compatible string.
>
> And how does that test anything ?

You can test that your code actually attaches the DT node to the
probed device. Without you code the test would fail. Wit it, it would
pass.

Regards,
Simon