Re: [PATCH v4 6/6] PCI: of: Create device-tree PCI host bridge node

Bjorn Helgaas
2024-12-04T21:48:53Z

On Mon, Dec 02, 2024 at 02:15:18PM +0100, Herve Codina wrote:
> PCI devices device-tree nodes can be already created. This was
> introduced by commit 407d1a51921e ("PCI: Create device tree node for
> bridge").
>
> In order to have device-tree nodes related to PCI devices attached on
> their PCI root bus (the PCI bus handled by the PCI host bridge), a PCI
> root bus device-tree node is needed. This root bus node will be used as
> the parent node of the first level devices scanned on the bus. On
> device-tree based systems, this PCI root bus device tree node is set to
> the node of the related PCI host bridge. The PCI host bridge node is
> available in the device-tree used to describe the hardware passed at
> boot.
>
> On non device-tree based system (such as ACPI), a device-tree node for
> the PCI host bridge or for the root bus do not exist. Indeed, the PCI
> host bridge is not described in a device-tree used at boot simply
> because no device-tree are passed at boot.

s/do not exist/does not exist/

> +void of_pci_make_host_bridge_node(struct pci_host_bridge *bridge)
> +{
> + struct device_node *np = NULL;
> + struct of_changeset *cset;
> + const char *name;
> + int ret;
> +
> + /*
> + * If there is already a device-tree node linked to the PCI bus handled
> + * by this bridge (i.e. the PCI root bus), nothing to do.
> + */
> + if (pci_bus_to_OF_node(bridge->bus))
> + return;
> +
> + /* The root bus has no node. Check that the host bridge has no node too */
> + if (bridge->dev.of_node) {
> + pr_err("PCI host bridge of_node already set");

Can we use dev_err() here?

Bjorn