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

[Bin Meng]

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.

> +                       }
> +
>                         *devp = dev;
>                         return 0;
>                 }
> --

Regards,
Bin