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

[Bin Meng <bmeng.cn@gmail.com>]

Hi Marek,

On Wed, Aug 8, 2018 at 9:24 PM, Marek Vasut <marek.vasut@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@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@gmail.com>
>>> Cc: Simon Glass <sjg@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.

Regards,
Bin