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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A195C7EE2F for ; Fri, 9 Jun 2023 14:52:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239837AbjFIOww (ORCPT ); Fri, 9 Jun 2023 10:52:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231841AbjFIOwv (ORCPT ); Fri, 9 Jun 2023 10:52:51 -0400 Received: from mail-lj1-x234.google.com (mail-lj1-x234.google.com [IPv6:2a00:1450:4864:20::234]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B9B92D48 for ; Fri, 9 Jun 2023 07:52:48 -0700 (PDT) Received: by mail-lj1-x234.google.com with SMTP id 38308e7fff4ca-2b1b3836392so20944471fa.0 for ; Fri, 09 Jun 2023 07:52:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1686322367; x=1688914367; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=ytR9MFcgJFjU0KeCb0QynViZURhhNB2rI5a4kf4EOfE=; b=If656WD9AuMcDX43YT9UOK3YuG8PxW7XUjN/uvyXFyX/HIky9sEapTbFF4V5i70pYQ jXVNFnW5KirPO6h5F4wDml/Xu1YIG2yUP+vXNiY0Mrhfi4VbPSdPK1ZHQlyZrkpJXFsb xG6kextoAxDcFQRSrfXYLtbdrTLiaGotnz/8qj0e/Dn9G5pwHLT9AMqroKZzG5XEzCci x4u34AnstyxYHnx/umvWRsbaKXQWBYT0uE4wGUYRvtUK5T2danVjYl550rpuE2ZVTjnL KcDXYLyi+/lWZhQCpSyqmTgkTiDDPUAZ5qQ8tuBA3a0RIsp/16BBInUOcDuy8ZcfXaWC Ks2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686322367; x=1688914367; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ytR9MFcgJFjU0KeCb0QynViZURhhNB2rI5a4kf4EOfE=; b=IMDj9Mt0yZ1P889R5aPJZ3a2PDgkdgXMD+HEk5eOsbaXxaMZgfH+rv+yJcyDlSMz73 KjJ41gb6d4mQ+7RV1Bx/zGgFu3GyNQqgL8ixUkBVMLmGMJxsh1zq43vc/occStQ1f9XW YPavJcQ6/2AtPRnY5uCuM6XOb1I8eXgG0ogiL0Xx6Dbz4tdtM9vbeP/lTKSfYFn6cfpH lkOntFSZgpYbIvvvcCggpwoNiulkmMZAMARwfXYrP1bdzpGPg+LmiUi2AUN8YOR/Bdgs BjN3ozN/af0fwZS/WpdZKbU1e4GJyuyf8IrNOfraLenRj+Ggus6x9BWjnFvz4TgDpcb3 6wUQ== X-Gm-Message-State: AC+VfDz/moYa29cOmELZzHaiEATbYyZAO8GgMd+GRAU55oOcsZllRLJh aOtXb9PQVp/yayFBorC2N8Egxg== X-Google-Smtp-Source: ACHHUZ6p8J+gs0jIQ4AOzs+OWU43jonUXrSgri5LlgXTp2LKnK6h1xF8IXFP3nkwV/aH1pek+nY+Og== X-Received: by 2002:a2e:8217:0:b0:2b1:bc73:6fa with SMTP id w23-20020a2e8217000000b002b1bc7306famr1306330ljg.21.1686322366828; Fri, 09 Jun 2023 07:52:46 -0700 (PDT) Received: from [192.168.1.101] (abyj190.neoplus.adsl.tpnet.pl. [83.9.29.190]) by smtp.gmail.com with ESMTPSA id p26-20020a2ea41a000000b002adbedc9962sm420713ljn.46.2023.06.09.07.52.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 09 Jun 2023 07:52:46 -0700 (PDT) Message-ID: Date: Fri, 9 Jun 2023 16:52:44 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.2 Subject: Re: [PATCH 0/3] arm64: dts: qcom: sa8775p: Add interconnect to SMMU Content-Language: en-US To: Robin Murphy , Parikshit Pareek Cc: Will Deacon , Joerg Roedel , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andy Gross , Bjorn Andersson , Manivannan Sadhasivam , Dmitry Baryshkov , Marijn Suijten , Adam Skladowski , linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, devicetree@vger.kernel.org, "linux-kernel @ vger . kernel . org Prasanna Kumar" , Shazad Hussain References: <20230609054141.18938-1-quic_ppareek@quicinc.com> <79206b05-674b-1f6c-6eb1-ed45e6bd5637@linaro.org> <20230609125631.GA29252@hu-ppareek-blr.qualcomm.com> <2881f374-70e2-0057-f43e-7be12d32ae22@arm.com> From: Konrad Dybcio In-Reply-To: <2881f374-70e2-0057-f43e-7be12d32ae22@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 9.06.2023 16:45, Robin Murphy wrote: > On 2023-06-09 13:56, Parikshit Pareek wrote: >> On Fri, Jun 09, 2023 at 10:52:26AM +0200, Konrad Dybcio wrote: >>> >>> >>> On 9.06.2023 07:41, Parikshit Pareek wrote: >>>> Some qcom SoCs have SMMUs, which need the interconnect bandwidth to be >>>> This series introduce the due support for associated interconnect, and >>>> setting of the due interconnect-bandwidth. Setting due interconnect >>>> bandwidth is needed to avoid the issues like [1], caused by not having >>>> due clock votes(indirectly dependent upon interconnect bandwidth). >>> >>> [1] ??? >> >> My bad. Intended to mention following: >> https://lore.kernel.org/linux-arm-msm/20230418165224.vmok75fwcjqdxspe@echanude/ > > This sounds super-dodgy - do you really have to rely on configuration of the interconnect path from the SMMU's pagetable walker to RAM to keep a completely different interconnect path clocked for the CPU to access SMMU registers? You can't just request the programming interface clock directly like on other SoCs? On Qualcomm platforms, particularly so with the more recent ones, some clocks are managed by various remote cores. Half of what the interconnect infra does on these SoCs is telling one such core to change the internally managed clock's rate based on the requested bw. Konrad > > Thanks, > Robin.