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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48DCFC46460 for ; Tue, 14 Aug 2018 12:25:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0B322172C for ; Tue, 14 Aug 2018 12:25:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="afkptQZW"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="afkptQZW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0B322172C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732304AbeHNPL4 (ORCPT ); Tue, 14 Aug 2018 11:11:56 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:57368 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729108AbeHNPLz (ORCPT ); Tue, 14 Aug 2018 11:11:55 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id E0F6860D98; Tue, 14 Aug 2018 12:24:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1534249498; bh=+Hj724E7ljRFHT53uSntaYQKlAYMv2pEpRc/2dWrVng=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=afkptQZWJ7ysh1Zg8O2ulOKWZy8r7DW6obkk9JmxcIdPsYYFkhJsdISWCa3bEWDlJ CsPvrMVJ4KWdCe0k9iyJiULvWJhG35bWpts++wGXFIr0ZphlGQWTZSKVubndOGudza bZH0E1MJdgENa0DDrSCk+sn4/YU4vnaysvybeSVY= Received: from [10.79.40.124] (blr-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.18.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vivek.gautam@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id D407D60D88; Tue, 14 Aug 2018 12:24:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1534249498; bh=+Hj724E7ljRFHT53uSntaYQKlAYMv2pEpRc/2dWrVng=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=afkptQZWJ7ysh1Zg8O2ulOKWZy8r7DW6obkk9JmxcIdPsYYFkhJsdISWCa3bEWDlJ CsPvrMVJ4KWdCe0k9iyJiULvWJhG35bWpts++wGXFIr0ZphlGQWTZSKVubndOGudza bZH0E1MJdgENa0DDrSCk+sn4/YU4vnaysvybeSVY= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D407D60D88 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org Subject: Re: [PATCH 0/5] Qcom smmu-500 TLB invalidation errata for sdm845 To: Will Deacon Cc: joro@8bytes.org, andy.gross@linaro.org, robin.murphy@arm.com, bjorn.andersson@linaro.org, iommu@lists.linux-foundation.org, mark.rutland@arm.com, david.brown@linaro.org, tfiga@chromium.org, swboyd@chromium.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, robdclark@gmail.com References: <20180814105528.20592-1-vivek.gautam@codeaurora.org> <20180814114009.GF28664@arm.com> From: Vivek Gautam Message-ID: Date: Tue, 14 Aug 2018 17:54:50 +0530 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180814114009.GF28664@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Will, On 8/14/2018 5:10 PM, Will Deacon wrote: > Hi Vivek, > > On Tue, Aug 14, 2018 at 04:25:23PM +0530, Vivek Gautam wrote: >> Qcom's implementation of arm,mmu-500 on sdm845 has a functional/performance >> errata [1] because of which the TCU cache look ups are stalled during >> invalidation cycle. This is mitigated by serializing all the invalidation >> requests coming to the smmu. > How does this implementation differ from the one supported by qcom_iommu.c? > I notice you're adding firmware hooks here, which we avoided by having the > extra driver. Please help me understand which devices exist, how they > differ, and which drivers are intended to support them! IIRC, the qcom_iommu driver was intended to support the static context bank - SID mapping, and is very specific to the smmu-v2 version present on msm8916 soc. However, this is the qcom's mmu-500 implementation specific errata. qcom_iommu will not be able to support mmu-500 configurations. Rob Clark can add more. Let you know what you suggest. > > Also -- you didn't CC all the maintainers for the firmware bits, so adding > Andy here for that, and Rob for the previous question. I added Andy to the series, would you want me to add Rob H also? Best regards Vivek > > Thanks, > > Will