Re: [PATCH v3 0/4] DT schema changes for HiKey970 PCIe hardware to work

From: Rob Herring <robh@kernel.org>
To: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Linuxarm <linuxarm@huawei.com>,
	mauro.chehab@huawei.com, Binghui Wang <wangbinghui@hisilicon.com>,
	Gustavo Pimentel <gustavo.pimentel@synopsys.com>,
	Jingoo Han <jingoohan1@gmail.com>,
	Xiaowei Song <songxiaowei@hisilicon.com>,
	devicetree@vger.kernel.org,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	PCI <linux-pci@vger.kernel.org>,
	linux-phy@lists.infradead.org
Subject: Re: [PATCH v3 0/4] DT schema changes for HiKey970 PCIe hardware to work
Date: Wed, 4 Aug 2021 10:28:53 -0600	[thread overview]
Message-ID: <YQrARd7wgYS1nywt@robh.at.kernel.org> (raw)
In-Reply-To: <20210804085045.3dddbb9c@coco.lan>

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@kernel.org> escreveu:
> 
> > On Mon, Aug 2, 2021 at 10:39 PM Mauro Carvalho Chehab
> > <mchehab+huawei@kernel.org> 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.

In the mean time, I applied the series but haven't pushed it out.

Rob