Re: [PATCH v4 6/6] PCI: of: Create device-tree PCI host bridge node
From: Herve Codina
Date: Thu Dec 05 2024 - 02:38:14 EST
Hi Bjorn,
On Wed, 4 Dec 2024 15:48:52 -0600
Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> 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/
Will be fix in the next iteration.
>
> > +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?
Yes indeed.
Will be change in the next iteration.
Best regards,
Hervé