Re: [PATCH v2 04/11] PCI: dwc: pcie-kirin: add support for Kirin 970 PCIe controller

From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Rob Herring <robh@kernel.org>,
	Binghui Wang <wangbinghui@hisilicon.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Xiaowei Song <songxiaowei@hisilicon.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	PCI <linux-pci@vger.kernel.org>
Subject: Re: [PATCH v2 04/11] PCI: dwc: pcie-kirin: add support for Kirin 970 PCIe controller
Date: Fri, 26 Mar 2021 14:21:02 +0530	[thread overview]
Message-ID: <20210326085102.GA25371@work> (raw)
In-Reply-To: <20210326093936.02ba3a03@coco.lan>

On Fri, Mar 26, 2021 at 09:39:36AM +0100, Mauro Carvalho Chehab wrote:
> Em Wed, 3 Feb 2021 08:34:21 -0600
> Rob Herring <robh@kernel.org> escreveu:
> 
> > On Wed, Feb 3, 2021 at 1:02 AM Mauro Carvalho Chehab
> > <mchehab+huawei@kernel.org> wrote:
> > >
> > > From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > >
> > > Add support for HiSilicon Kirin 970 (hi3670) SoC PCIe controller, based
> > > on Synopsys DesignWare PCIe controller IP.
> > >
> > > [mchehab+huawei@kernel.org: fix merge conflicts]
> > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> > > ---
> > >  drivers/pci/controller/dwc/pcie-kirin.c | 723 +++++++++++++++++++++++-
> > >  1 file changed, 707 insertions(+), 16 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/dwc/pcie-kirin.c b/drivers/pci/controller/dwc/pcie-kirin.c
> > > index 026fd1e42a55..5925d2b345a8 100644
> > > --- a/drivers/pci/controller/dwc/pcie-kirin.c
> > > +++ b/drivers/pci/controller/dwc/pcie-kirin.c
> > > @@ -29,6 +29,7 @@
> > 

[...]

> > This looks like it is almost all phy related. I think it should all be
> > moved to a separate phy driver. Yes, we have some other PCI drivers
> > controlling their phys directly where the phy registers are
> > intermingled with the PCI host registers, but I think those either
> > predate the phy subsystem or are really simple. I also have a dream to
> > move all the phy control to the DWC core code.
> 
> Please notice that this patch was not written by me, but, instead,
> by Mannivannan. So, I can't change it.

Feel free to move the PHY pieces to a separate PHY driver as suggested.
My driver code was merely WIP one and I don't have any objection to
change the patch.

I'd be happy if you add my Co-developed tag to the PCIe driver patch with
the SoB ofc.

> What I can certainly do is to
> write a separate patch at the end of this series moving the Kirin 970
> phy to a separate driver. Would this be accepted?
> 

Ah, please don't do that. I know that you've already followed the same
process for other HiSi drivers but that looks messy IMO.

> Btw, what should be done with the Kirin 960 PHY code that it is
> already embedded on this driver, and whose some of the DT properties
> are for its phy layer? 
> 

You might need to create a PHY driver for both 960 and 970. I don't see
any harm there. But please make sure you test the patches on both boards.

Thanks,
Mani

> Thanks,
> Mauro