Re: [PATCH v2 5/6] PCI: dwc: rcar-gen4: Add support for other R-Car Gen4 PCIe controller

From: Bjorn Helgaas <helgaas@kernel.org>
To: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: "lpieralisi@kernel.org" <lpieralisi@kernel.org>,
	"kw@linux.com" <kw@linux.com>,
	"robh@kernel.org" <robh@kernel.org>,
	"bhelgaas@google.com" <bhelgaas@google.com>,
	"krzysztof.kozlowski+dt@linaro.org"
	<krzysztof.kozlowski+dt@linaro.org>,
	"conor+dt@kernel.org" <conor+dt@kernel.org>,
	"jingoohan1@gmail.com" <jingoohan1@gmail.com>,
	"gustavo.pimentel@synopsys.com" <gustavo.pimentel@synopsys.com>,
	"mani@kernel.org" <mani@kernel.org>,
	"marek.vasut+renesas@gmail.com" <marek.vasut+renesas@gmail.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-renesas-soc@vger.kernel.org"
	<linux-renesas-soc@vger.kernel.org>
Subject: Re: [PATCH v2 5/6] PCI: dwc: rcar-gen4: Add support for other R-Car Gen4 PCIe controller
Date: Wed, 27 Mar 2024 13:14:51 -0500	[thread overview]
Message-ID: <20240327181451.GA1531625@bhelgaas> (raw)
In-Reply-To: <TYCPR01MB110402EB3E15B3471C7F526C7D8342@TYCPR01MB11040.jpnprd01.prod.outlook.com>

On Wed, Mar 27, 2024 at 05:32:57AM +0000, Yoshihiro Shimoda wrote:
> > From: Bjorn Helgaas, Sent: Wednesday, March 27, 2024 5:49 AM

> > >  static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
> > >  {
> > > +	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> > > +	if (IS_ERR(rcar->phy_base))
> > > +		return PTR_ERR(rcar->base);
> > 
> > I don't get it.  This imposes a new requirement (presence of "phy"
> > resource) on the existing SoCs.  That doesn't sound right.
> 
> According to the dt-binding doc, the existing SoCs are also required
> for the "phy".  That's why I didn't add any condition to simplify
> the code.

Is there anything that enforces that?  Is it possible that DTs exist
in the field without it?  We don't want to break any existing setup.