From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D7CC02690C8; Thu, 13 Mar 2025 16:06:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741882011; cv=none; b=Bx7mhlwPHogboAaw8dnVCAtf0zOCmXr8+q3PILrh961f6sgf6elQTYCW39OxP4HflUa+qw3E/YvKl6H/ebs3phP37S+rXBm4/Pke++pQ0H3J3qA7n8gqvUN5ZUCZTZ8EwHAbP9Onv/O2L3LXkPX67OLMpv40BpKCAufU9dPZAuI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741882011; c=relaxed/simple; bh=Mx/+tLwb7T1JrZ/ABp2sKGt2Jj7jvlKNBLxVpfOsVnI=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=DjiNSwh4gksj4LcirrkAS+M9NWm44jHUAcWl+rgdq766w8SzkzLUayyoEB0zw7la7tcBTEHagy0WUG+FdoPdH0Yx8J8LLQaZn92B342qB9qIsF1FAe4KwS9oAWEliqqEwGiMTFgPwPrMzQlDPSAHKs7spj0igM0wEE+IfL/o7bY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ocuFDpji; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ocuFDpji" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24824C4CEDD; Thu, 13 Mar 2025 16:06:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741882010; bh=Mx/+tLwb7T1JrZ/ABp2sKGt2Jj7jvlKNBLxVpfOsVnI=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=ocuFDpjice0CwzZV+U1r2wGc/B4uqAhc1SLsAhGo3hZOCubtpYEujpWK0xMah00Qx Nkhy4eoJwBeQ04rISAQUc07RqNf8z1clfjRrJjXlpOXTOS0tYGyED432lopKTutbS5 IerUm1HplPYC5RsM7OpEJvov9V+kvXHi8PJcKfWfaOj3ht7GfIPTwdVBwyDGfdqHOR KHp/fJsQB7u0+joeFsu3ruw68crrUu/wdrUniAW8SwtRtG+5E9HKiSlR4JHSA0iviI tfjWtOg4fPJTNvZbMJi0Mzuqn/PskRw2flaNg6mxClK5//ywkFwTQgQ36xUL35JB+x iKuTzrcXpm0Ww== Date: Thu, 13 Mar 2025 11:06:48 -0500 From: Bjorn Helgaas To: Lucas Stach Cc: Frank Li , Hongxing Zhu , "robh@kernel.org" , "krzk+dt@kernel.org" , "conor+dt@kernel.org" , "shawnguo@kernel.org" , "lpieralisi@kernel.org" , "kw@linux.com" , "manivannan.sadhasivam@linaro.org" , "bhelgaas@google.com" , "s.hauer@pengutronix.de" , "festevam@gmail.com" , "devicetree@vger.kernel.org" , "linux-pci@vger.kernel.org" , "imx@lists.linux.dev" , "kernel@pengutronix.de" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v1 2/2] PCI: imx6: Use domain number replace the hardcodes Message-ID: <20250313160648.GA736867@bhelgaas> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Thu, Mar 13, 2025 at 09:54:25AM +0100, Lucas Stach wrote: > Am Mittwoch, dem 12.03.2025 um 10:22 -0400 schrieb Frank Li: > > On Wed, Mar 12, 2025 at 09:28:02AM +0100, Lucas Stach wrote: > > > Am Mittwoch, dem 12.03.2025 um 04:05 +0000 schrieb Hongxing Zhu: > > > > > -----Original Message----- > > > > > From: Bjorn Helgaas > > > > > Sent: 2025年3月11日 23:55 > > > > > To: Hongxing Zhu > > > > > Cc: robh@kernel.org; krzk+dt@kernel.org; conor+dt@kernel.org; > > > > > shawnguo@kernel.org; l.stach@pengutronix.de; lpieralisi@kernel.org; > > > > > kw@linux.com; manivannan.sadhasivam@linaro.org; bhelgaas@google.com; > > > > > s.hauer@pengutronix.de; festevam@gmail.com; devicetree@vger.kernel.org; > > > > > linux-pci@vger.kernel.org; imx@lists.linux.dev; kernel@pengutronix.de; > > > > > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org > > > > > Subject: Re: [PATCH v1 2/2] PCI: imx6: Use domain number replace the > > > > > hardcodes > > > > > > > > > > On Tue, Mar 11, 2025 at 01:11:04AM +0000, Hongxing Zhu wrote: > > > > > > > -----Original Message----- > > > > > > > From: Bjorn Helgaas > > > > > > > Sent: 2025年3月10日 23:11 > > > > > > > To: Hongxing Zhu > > > > > > > Cc: robh@kernel.org; krzk+dt@kernel.org; conor+dt@kernel.org; > > > > > > > shawnguo@kernel.org; l.stach@pengutronix.de; lpieralisi@kernel.org; > > > > > > > kw@linux.com; manivannan.sadhasivam@linaro.org; > > > > > bhelgaas@google.com; > > > > > > > s.hauer@pengutronix.de; festevam@gmail.com; > > > > > > > devicetree@vger.kernel.org; linux-pci@vger.kernel.org; > > > > > > > imx@lists.linux.dev; kernel@pengutronix.de; > > > > > > > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org > > > > > > > Subject: Re: [PATCH v1 2/2] PCI: imx6: Use domain number replace the > > > > > > > hardcodes > > > > > > > > > > > > > > On Wed, Feb 26, 2025 at 10:42:56AM +0800, Richard Zhu wrote: > > > > > > > > Use the domain number replace the hardcodes to uniquely identify > > > > > > > > different controller on i.MX8MQ platforms. No function changes. > > > > > > > > > > > > > > > > Signed-off-by: Richard Zhu > > > > > > > > --- > > > > > > > >  drivers/pci/controller/dwc/pci-imx6.c | 14 ++++++-------- > > > > > > > >  1 file changed, 6 insertions(+), 8 deletions(-) > > > > > > > > > > > > > > > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c > > > > > > > > b/drivers/pci/controller/dwc/pci-imx6.c > > > > > > > > index 90ace941090f..ab9ebb783593 100644 > > > > > > > > --- a/drivers/pci/controller/dwc/pci-imx6.c > > > > > > > > +++ b/drivers/pci/controller/dwc/pci-imx6.c > > > > > > > > @@ -41,7 +41,6 @@ > > > > > > > >  #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11) > > > > > > > >  #define IMX8MQ_GPR_PCIE_VREG_BYPASS BIT(12) > > > > > > > >  #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, > > > > > 8) > > > > > > > > -#define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000 > > > > > > > > > > > > > > > >  #define IMX95_PCIE_PHY_GEN_CTRL 0x0 > > > > > > > >  #define IMX95_PCIE_REF_USE_PAD BIT(17) > > > > > > > > @@ -1474,7 +1473,6 @@ static int imx_pcie_probe(struct > > > > > > > > platform_device > > > > > > > *pdev) > > > > > > > >   struct dw_pcie *pci; > > > > > > > >   struct imx_pcie *imx_pcie; > > > > > > > >   struct device_node *np; > > > > > > > > - struct resource *dbi_base; > > > > > > > >   struct device_node *node = dev->of_node; > > > > > > > >   int i, ret, req_cnt; > > > > > > > >   u16 val; > > > > > > > > @@ -1515,10 +1513,6 @@ static int imx_pcie_probe(struct > > > > > > > platform_device *pdev) > > > > > > > >   return PTR_ERR(imx_pcie->phy_base); > > > > > > > >   } > > > > > > > > > > > > > > > > - pci->dbi_base = devm_platform_get_and_ioremap_resource(pdev, > > > > > 0, > > > > > > > &dbi_base); > > > > > > > > - if (IS_ERR(pci->dbi_base)) > > > > > > > > - return PTR_ERR(pci->dbi_base); > > > > > > > > > > > > > > This makes me wonder. > > > > > > > > > > > > > > IIUC this means that previously we set controller_id to > > > > > > > 1 if the first item in devicetree "reg" was 0x33c00000, > > > > > > > and now we will set controller_id to 1 if the devicetree > > > > > > > "linux,pci-domain" property is 1. This is good, but I > > > > > > > think this new dependency on the correct > > > > > > > "linux,pci-domain" in devicetree should be mentioned in > > > > > > > the commit log. > > > > > > > > > > > > > > My bigger worry is that we no longer set pci->dbi_base > > > > > > > at all. I see that the only use of pci->dbi_base in > > > > > > > pci-imx6.c was to determine the controller_id, but this > > > > > > > is a DWC-based driver, and the DWC core certainly uses > > > > > > > pci->dbi_base. Are we sure that none of those DWC core > > > > > > > paths are important to pci-imx6.c? > > > > > > > > > > > > Thanks for your concerns. Don't worry about the > > > > > > assignment of pci->dbi_base. If pci-imx6.c driver doesn't > > > > > > set it. DWC core driver would set it when > > > > > >  dw_pcie_get_resources() is invoked. > > > > > > > > > > Great, thanks! Maybe we can amend the commit log to mention > > > > > that and the new "linux,pci-domain" dependency. > > > > > > > > How about the following updates of the commit log? > > > > > > > > Use the domain number replace the hardcodes to uniquely > > > > identify different controller on i.MX8MQ platforms. No > > > > function changes. Please make sure the " linux,pci-domain" is > > > > set for i.MX8MQ correctly, since  the controller id is relied > > > > on it totally. > > > > > > > This breaks running a new kernel on an old DT without the > > > linux,pci-domain property, which I'm absolutely no fan of. We > > > tried really hard to keep this way around working in the i.MX > > > world. > > > > 8MQ already add linux,pci-domain since Jan, 2021 > > > > commit c0b70f05c87f3b09b391027c6f056d0facf331ef > > Author: Peng Fan > > Date: Fri Jan 15 11:26:57 2021 +0800 > > > > Only missed is pcie-ep side, which have not been used at all boards dts > > file in upstream. > > I wasn't aware of this. 2021 is quite a while ago, so I suspect that > nobody is going to run a new kernel with a DT this old. I retract my > objection. Sounds good, thanks, Lucas. We really do want to avoid breaking old DTs, so I appreciate your highlighting of it. Even if we believe none of them will break, I think it's worth mentioning the 'linux,pci-domain' dependency and the commit that added it to the .dtsi in the commit log. Bjorn