LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Chuanjia Liu <chuanjia.liu@mediatek.com>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: <robh+dt@kernel.org>, <bhelgaas@google.com>,
	<matthias.bgg@gmail.com>, <lorenzo.pieralisi@arm.com>,
	<ryder.lee@mediatek.com>, <jianjun.wang@mediatek.com>,
	<yong.wu@mediatek.com>, <linux-pci@vger.kernel.org>,
	<linux-mediatek@lists.infradead.org>,
	<devicetree@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v12 2/6] PCI: mediatek: Add new method to get shared pcie-cfg base address
Date: Tue, 31 Aug 2021 11:31:24 +0800	[thread overview]
Message-ID: <ccf767340afe13a6d273ad8fbc29c6bc966d6314.camel@mediatek.com> (raw)
In-Reply-To: <20210830214317.GA27606@bjorn-Precision-5520>

On Mon, 2021-08-30 at 16:43 -0500, Bjorn Helgaas wrote:
> On Mon, Aug 30, 2021 at 03:09:44PM +0800, Chuanjia Liu wrote:
> > On Fri, 2021-08-27 at 11:46 -0500, Bjorn Helgaas wrote:
> > > On Mon, Aug 23, 2021 at 11:27:56AM +0800, Chuanjia Liu wrote:
> > > > @@ -995,6 +1004,14 @@ static int mtk_pcie_subsys_powerup(struct
> > > > mtk_pcie *pcie)
> > > >  			return PTR_ERR(pcie->base);
> > > >  	}
> > > >  
> > > > +	cfg_node = of_find_compatible_node(NULL, NULL,
> > > > +					   "mediatek,generic-
> > > > pciecfg");
> > > > +	if (cfg_node) {
> > > > +		pcie->cfg = syscon_node_to_regmap(cfg_node);
> > > 
> > > Other drivers in drivers/pci/controller/ use
> > > syscon_regmap_lookup_by_phandle() (j721e, dra7xx, keystone,
> > > layerscape, artpec6) or syscon_regmap_lookup_by_compatible()
> > > (imx6,
> > > kirin, v3-semi).
> > > 
> > > You should do it the same way unless there's a need to be
> > > different.
> > 
> > I have used phandle, but Rob suggested to search for the node by 
> > compatible.
> > The reason why syscon_regmap_lookup_by_compatible() is not 
> > used here is that the pciecfg node is optional, and there is no
> > need to
> > return error when the node is not searched.
> 
> How about this?
> 
>   regmap = syscon_regmap_lookup_by_compatible("mediatek,generic-
> pciecfg");
>   if (!IS_ERR(regmap))
>     pcie->cfg = regmap;

Hi Bjorn,

We need to deal with three situations
1) No error
2) The error of the node not found, don't do anything 
3) Other errors, return errors

I guess you mean

regmap = syscon_regmap_lookup_by_compatible("mediatek,generic-
pciecfg");
  if (!IS_ERR(regmap))
      pcie->cfg = regmap;
  else if (IS_ERR(regmap) && PTR_ERR(regmap) != -ENODEV)
      return PTR_ERR(regmap);

I'm not sure if we need this, it seems a little weird and there are
many drivers in other subsystems that use syscon_node_to_regmap().

Thanks
Chuanjia

  reply	other threads:[~2021-08-31  3:31 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-23  3:27 [PATCH v12 0/6] PCI: mediatek: Spilt PCIe node to comply with hardware design Chuanjia Liu
2021-08-23  3:27 ` [PATCH v12 1/6] dt-bindings: PCI: mediatek: Update the Device tree bindings Chuanjia Liu
2021-08-23  3:27 ` [PATCH v12 2/6] PCI: mediatek: Add new method to get shared pcie-cfg base address Chuanjia Liu
2021-08-27 16:46   ` Bjorn Helgaas
2021-08-30  7:09     ` Chuanjia Liu
2021-08-30 21:43       ` Bjorn Helgaas
2021-08-31  3:31         ` Chuanjia Liu [this message]
2021-08-31 15:17           ` Rob Herring
2021-09-02  9:34             ` Chuanjia Liu
2021-08-31 15:04     ` Rob Herring
2021-08-31 15:47       ` Bjorn Helgaas
2021-08-31 18:24         ` Rob Herring
2021-08-23  3:27 ` [PATCH v12 3/6] PCI: mediatek: Add new method to get irq number Chuanjia Liu
2021-08-31 18:30   ` Bjorn Helgaas
2021-09-02  9:28     ` Chuanjia Liu
2021-08-23  3:27 ` [PATCH v12 4/6] PCI: mediatek: Get pci domain and decide how to parse node Chuanjia Liu
2021-08-23  3:27 ` [PATCH v12 5/6] arm64: dts: mediatek: Split PCIe node for MT2712 and MT7622 Chuanjia Liu
2021-09-21 18:43   ` Matthias Brugger
2021-08-23  3:28 ` [PATCH v12 6/6] ARM: dts: mediatek: Update MT7629 PCIe node for new format Chuanjia Liu
2021-09-21 18:43   ` Matthias Brugger
2021-08-26 12:53 ` [PATCH v12 0/6] PCI: mediatek: Spilt PCIe node to comply with hardware design Lorenzo Pieralisi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=ccf767340afe13a6d273ad8fbc29c6bc966d6314.camel@mediatek.com \
    --to=chuanjia.liu@mediatek.com \
    --cc=bhelgaas@google.com \
    --cc=devicetree@vger.kernel.org \
    --cc=helgaas@kernel.org \
    --cc=jianjun.wang@mediatek.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=matthias.bgg@gmail.com \
    --cc=robh+dt@kernel.org \
    --cc=ryder.lee@mediatek.com \
    --cc=yong.wu@mediatek.com \
    --subject='Re: [PATCH v12 2/6] PCI: mediatek: Add new method to get shared pcie-cfg base address' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).