Em Wed, 4 Aug 2021 10:28:53 -0600
Rob Herring <robh@xxxxxxxxxx> escreveu:
> On Wed, Aug 04, 2021 at 08:50:45AM +0200, Mauro Carvalho Chehab wrote:
> > Em Tue, 3 Aug 2021 16:11:42 -0600
> > Rob Herring <robh+dt@xxxxxxxxxx> escreveu:
> >
> > > On Mon, Aug 2, 2021 at 10:39 PM Mauro Carvalho Chehab
> > > <mchehab+huawei@xxxxxxxxxx> wrote:
> > > >
> > > > Hi Rob,
> > > >
> > > > That's the third version of the DT bindings for Kirin 970 PCIE and its
> > > > corresponding PHY.
> > > >
> > > > It is identical to v2, except by:
> > > > - pcie@7,0 { // Lane 7: Ethernet
> > > > + pcie@7,0 { // Lane 6: Ethernet
> > >
> > > Can you check whether you have DT node links in sysfs for the PCI
> > > devices? If you don't, then something is wrong still in the topology
> > > or the PCI core is failing to set the DT node pointer in struct
> > > device. Though you don't rely on that currently, we want the topology
> > > to match. It's possible this never worked on arm/arm64 as mainly
> > > powerpc relied on this.
> > >
> > > I'd like some way to validate the DT matches the PCI topology. We
> > > could have a tool that generates the DT structure based on the PCI
> > > topology.
> >
> > The of_node node link is on those places:
> >
> > $ find /sys/devices/platform/soc/f4000000.pcie/ -name of_node
> > /sys/devices/platform/soc/f4000000.pcie/of_node
> > /sys/devices/platform/soc/f4000000.pcie/pci0000:00/0000:00:00.0/of_node
> > /sys/devices/platform/soc/f4000000.pcie/pci0000:00/0000:00:00.0/pci_bus/0000:01/of_node
> > /sys/devices/platform/soc/f4000000.pcie/pci0000:00/pci_bus/0000:00/of_node
>
> Looks like we're missing some...
>
> It's not immediately obvious to me what's wrong here. Only the root
> bus is getting it's DT node set. The relevant code is pci_scan_device(),
> pci_set_of_node() and pci_set_bus_of_node(). Give me a few days to try
> to reproduce and debug it.
I added a printk on both pci_set_*of_node() functions:
[ 4.872991] (null): pci_set_bus_of_node: of_node: /soc/pcie@f4000000
[ 4.913806] (null): pci_set_of_node: of_node: /soc/pcie@f4000000
[ 4.978102] pci_bus 0000:01: pci_set_bus_of_node: of_node: /soc/pcie@f4000000/pcie@0,0
[ 4.990622] (null): pci_set_of_node: of_node: /soc/pcie@f4000000/pcie@0,0
[ 5.052383] pci_bus 0000:02: pci_set_bus_of_node: of_node: (null)
[ 5.059263] (null): pci_set_of_node: of_node: (null)
[ 5.085552] (null): pci_set_of_node: of_node: (null)
[ 5.112073] (null): pci_set_of_node: of_node: (null)
[ 5.138320] (null): pci_set_of_node: of_node: (null)
[ 5.164673] (null): pci_set_of_node: of_node: (null)
[ 5.233759] pci_bus 0000:03: pci_set_bus_of_node: of_node: (null)
[ 5.240539] (null): pci_set_of_node: of_node: (null)
[ 5.310545] pci_bus 0000:04: pci_set_bus_of_node: of_node: (null)
[ 5.324719] pci_bus 0000:05: pci_set_bus_of_node: of_node: (null)
[ 5.338914] pci_bus 0000:06: pci_set_bus_of_node: of_node: (null)
[ 5.345516] (null): pci_set_of_node: of_node: (null)
[ 5.415795] pci_bus 0000:07: pci_set_bus_of_node: of_node: (null)
It sounds that the parent is missing when pci_set_bus_of_node() is
called on some places. I'll try to identify why.
Thanks,
Mauro
