From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E1D22C54E5D for ; Tue, 19 Mar 2024 13:53:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=33ri1aXjRAgDsPbeWYEBwltUKtMGWBBScvxKcIQYCKo=; b=3LQj7NIfoInyQ+ it7oUOgyrHmsNy5eSgcoYYc+9uR7p+7wBe17R8lcSMU/8GpXyVoYBqvqlkoBgCbdOsop/DxzsYl+r cw+AiTkV6hUz88piQFyYsg9kEI5rBpgi0QmDtHUQC1i2Yycfu16YB1lk74gk38WRwLXwLAJ4WVQh0 kuoYwRHxlkSbePG27vhggu0M6sMXbPPeP1Jl6G3YkolJwf9chCCaX2zrlUerOel5nahTmb3VtmH44 KMyo6fZ1KHaOKkfkG4riw8pg4gbcqFhCGavojRypDP+JeGiTdRm0YDfUerz67skqi5wm6IBmLTdpe S9/yvzu4poYIVRofowIw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rmZuQ-0000000Cs7f-0tlZ; Tue, 19 Mar 2024 13:53:42 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rmZuM-0000000Cs5C-31jn for linux-arm-kernel@lists.infradead.org; Tue, 19 Mar 2024 13:53:40 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5F600106F; Tue, 19 Mar 2024 06:54:12 -0700 (PDT) Received: from [10.57.52.192] (unknown [10.57.52.192]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 123473F762; Tue, 19 Mar 2024 06:53:34 -0700 (PDT) Message-ID: <9b2a681e-1191-4cf7-8da7-14aa2c1fa455@arm.com> Date: Tue, 19 Mar 2024 13:53:32 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] dt-bindings: iommu: arm,smmu-v3: Add SC8280XP compatible Content-Language: en-GB To: Konrad Dybcio , Bjorn Andersson , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Will Deacon , Joerg Roedel , Rob Herring Cc: Marijn Suijten , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, Johan Hovold References: <20231219-topic-8280_smmuv3-v2-0-c67bd3226687@linaro.org> <20231219-topic-8280_smmuv3-v2-1-c67bd3226687@linaro.org> From: Robin Murphy In-Reply-To: <20231219-topic-8280_smmuv3-v2-1-c67bd3226687@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240319_065338_851312_916EFED0 X-CRM114-Status: GOOD ( 17.85 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2024-03-09 1:31 pm, Konrad Dybcio wrote: > The smmu-v3 binding currently doesn't differentiate the SoCs it's > implemented on. This is a poor design choice that may bite in the future, > should any quirks surface. That doesn't seem entirely fair to say - the vast majority of bindings don't have separate compatibles for every known integration of the same implementation in different SoCs. And in this case we don't have per-implementation compatibles for quirks and errata because the implementation is architecturally discoverable from the SMMU_IIDR register. We have the whole mess for QCom SMMUv2 because the effective *implementation* is a mix of hardware and hypervisor, whose behaviour does seem to vary on almost a per-SoC basis. I'm not at all keen to start repeating that here without very good reason, and that of "documenting" a device which we typically expect to not even be accessible isn't really convincing me... Thanks, Robin. > > Add a compatible for the instance found on Qualcomm SC8280XP. > > Signed-off-by: Konrad Dybcio > --- > Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > index 75fcf4cb52d9..f284f7b0c1d8 100644 > --- a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > +++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > @@ -20,7 +20,11 @@ properties: > $nodename: > pattern: "^iommu@[0-9a-f]*" > compatible: > - const: arm,smmu-v3 > + oneOf: > + - items: > + - const: qcom,sc8280xp-smmu-v3 > + - const: arm,smmu-v3 > + - const: arm,smmu-v3 > > reg: > maxItems: 1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel