[U-Boot] [PATCH] pci: Support parsing PCI controller DT subnodes

[Marek Vasut]

On 08/08/2018 03:39 PM, Bin Meng wrote:
> Hi Marek,
> 
> On Wed, Aug 8, 2018 at 9:24 PM, Marek Vasut <marek.vasut at gmail.com> wrote:
>> On 08/08/2018 03:14 PM, Bin Meng wrote:
>>> Hi Marek,
>>>
>>> On Wed, Aug 8, 2018 at 9:03 PM, Marek Vasut <marek.vasut at gmail.com> 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>
>>>> ---
>>>>  drivers/pci/pci-uclass.c | 14 ++++++++++++++
>>>>  1 file changed, 14 insertions(+)
>>>>
>>>> diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
>>>> index 46e9c71bdf..306bea0dbf 100644
>>>> --- a/drivers/pci/pci-uclass.c
>>>> +++ b/drivers/pci/pci-uclass.c
>>>> @@ -662,6 +662,8 @@ static int pci_find_and_bind_driver(struct udevice *parent,
>>>>                 for (id = entry->match;
>>>>                      id->vendor || id->subvendor || id->class_mask;
>>>>                      id++) {
>>>> +                       ofnode node;
>>>> +
>>>>                         if (!pci_match_one_id(id, find_id))
>>>>                                 continue;
>>>>
>>>> @@ -691,6 +693,18 @@ static int pci_find_and_bind_driver(struct udevice *parent,
>>>>                                 goto error;
>>>>                         debug("%s: Match found: %s\n", __func__, drv->name);
>>>>                         dev->driver_data = find_id->driver_data;
>>>> +
>>>> +                       dev_for_each_subnode(node, parent) {
>>>> +                               phys_addr_t df, size;
>>>> +                               df = ofnode_get_addr_size(node, "reg", &size);
>>>> +
>>>> +                               if (PCI_FUNC(df) == PCI_FUNC(bdf) &&
>>>> +                                   PCI_DEV(df) == PCI_DEV(bdf)) {
>>>> +                                       dev->node = node;
>>>> +                                       break;
>>>> +                               }
>>>
>>> The function pci_find_and_bind_driver() is supposed to bind devices
>>> that are NOT in the device tree. Adding device tree access in this
>>> routine is quite odd. You can add the EHCI controller that need such
>>> PHY subnodes in the device tree and there is no need to modify
>>> anything I believe. If you are looking for an example, please check
>>> pciuart0 in arch/x86/dts/crownbay.dts.
>>
>> Well this does not work for me, the EHCI PCI doesn't get a DT node
>> assigned, check r8a7794.dtsi for the PCI devices I use.
>>
> 
> I think that's because you don't specify a "compatible" string for
> these two EHCI PCI nodes.

That's perfectly fine, why should I specify it ? Linux has no problem
with it either.

-- 
Best regards,
Marek Vasut