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 953222F7ADE; Fri, 5 Dec 2025 13:14:44 +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=1764940484; cv=none; b=TCXKIENTDluDHkWBaB2BX0uyDZv/dQwBqu0I2FgBregjNedliKxRFT5y4lt1Jfu0UMAYXAWFm8btUS7H7S7PZ+NkL/853P+JBKBfzT0CVB2MbIECqcoOevxME9IPs8VlYwzNhOo7gXFQZfCThG9CwGaICJbfvCPPJdUljTKZlhM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764940484; c=relaxed/simple; bh=OnFV8M52MQ1fx9QsvZL97MqSp+jVOb4a/O9yUSS0J4E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qhgqs3BtS6M35JXDGKQI/GrhxuRaKFnuCbBRu6y5OSIZMA+JO5KMqdjn9dPv0v4YTO2ccJs1TkgGAcZ+Tc38VWQU7MX3iSb44k8ZFCgqpQrTM0DZryvuhdk38ki5jLZnNykDYJr3f8bijtPkv3I52f37kkSF4/d73NelO+6Zv/w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WmiUxdK/; 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="WmiUxdK/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE6E9C113D0; Fri, 5 Dec 2025 13:14:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764940484; bh=OnFV8M52MQ1fx9QsvZL97MqSp+jVOb4a/O9yUSS0J4E=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=WmiUxdK/26naJtIeK2IEsnq8Olgez6IpwDc5AuWUlbSftCuXjWB6qvP019Cly7ZK8 NzTrlqBci73zhCclAuOjmHJOJ37lzvZtoVvF1VO6CnFqioDhIpyCm4MmQgVVlj6O8U D/giq3p5IfnVjLTF9jrDu5GOZ+eCBmO28R6tWbADiNiruWmLKRMWxMzhKSdWPbc6JL r32uxx9U39Vfvsp5Bp2uqjHruV8C3wz4Flpm/od/23FH4TG7iXuyfbanGCDu3fQefr Dn7wXKatYT6OGRWPTO8KuGtrBZYOblZSc0mbwfe9rBEbj3ZUaXybe/VYK0nTWhZzz9 g1cKqEBrKoiSQ== Message-ID: <8bb852ac-1736-49db-be94-f6be9e500f74@kernel.org> Date: Fri, 5 Dec 2025 14:14:37 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] dt-bindings: PCI: qcom,pcie-ep-sa8255p: Document firmware managed PCIe endpoint To: Mrinmay Sarkar Cc: Bjorn Helgaas , Lorenzo Pieralisi , =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Philipp Zabel , linux-arm-msm@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@oss.qualcomm.com, Manivannan Sadhasivam , Krishna Chaitanya Chundru , quic_vbadigan@quicinc.com, quic_shazhuss@quicinc.com, konrad.dybcio@oss.qualcomm.com, Rama Krishna , Ayiluri Naga Rashmi , Nitesh Gupta References: <20251203-firmware_managed_ep-v1-0-295977600fa5@oss.qualcomm.com> <20251203-firmware_managed_ep-v1-1-295977600fa5@oss.qualcomm.com> <20251205-majestic-guillemot-of-criticism-80c18b@quoll> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 05/12/2025 13:58, Mrinmay Sarkar wrote: >>> 1 file changed, 114 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-ep-sa8255p.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-ep-sa8255p.yaml >>> new file mode 100644 >>> index 0000000000000000000000000000000000000000..970f65d46c8e2fa4c44665cb7a346dea1dc9e06a >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-ep-sa8255p.yaml >>> @@ -0,0 +1,114 @@ >>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >>> +%YAML 1.2 >>> +--- >>> +$id: http://devicetree.org/schemas/pci/qcom,pcie-ep-sa8255p.yaml# >>> +$schema: http://devicetree.org/meta-schemas/core.yaml# >>> + >>> +title: Qualcomm firmware managed PCIe Endpoint Controller >>> + >>> +description: >>> + Qualcomm SA8255p SoC PCIe endpoint controller is based on the Synopsys >>> + DesignWare PCIe IP which is managed by firmware. >>> + >>> +maintainers: >>> + - Manivannan Sadhasivam >>> + >>> +properties: >>> + compatible: >>> + const: qcom,sa8255p-pcie-ep >>> + >>> + reg: >>> + minItems: 6 >> >> Why is this flexible? > > The reason for `minItems: 6` is that the DMA register space can be > skipped if DMA is not used. But the hardware has this anyway, so this must be here. You do not write bindings depending how drivers use them in your use case. Either drop minItems (fixed size of array) or provide rationale in terms of hardware in commit msg. ... >>> + >>> + dma-coherent: true >>> + >>> + num-lanes: >>> + default: 2 >> >> Isn't this deducible from the compatible? Do you have have different >> PCIe controllers with different lanes? > > SA8255p has 2 pcie controllers(pcie0 and pcie1). > pcie0 supports 2 lanes, and pcie1 supports 4 lanes. That's ok, thanks. Best regards, Krzysztof