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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 168D9C433E0 for ; Wed, 17 Mar 2021 09:33:31 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9405764F41 for ; Wed, 17 Mar 2021 09:33:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9405764F41 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C3C1E89C56; Wed, 17 Mar 2021 09:33:29 +0000 (UTC) Received: from m42-10.mailgun.net (m42-10.mailgun.net [69.72.42.10]) by gabe.freedesktop.org (Postfix) with ESMTPS id B7FA889C52 for ; Wed, 17 Mar 2021 09:33:25 +0000 (UTC) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1615973608; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=lZUJUo3Pug7BWyZZPzQMe4b62SCJmcae+oC4ypNhr2I=; b=tXhNOFwbB1qXnIEoAt2QT4FRIij5szEsVolb4nsGhI8oNCVSSNTlm8bZJZ5834bb3F5EPAFY U/DoZw8epQlYGgwKGtPimwXeEaBOGr0rCBXO84P4boyBiXRBAYQYIPGp7+djoVg9E0Y1WTbZ y4hQZclSNbpY0pJUDJv9b+a7nw8= X-Mailgun-Sending-Ip: 69.72.42.10 X-Mailgun-Sid: WyJkOTU5ZSIsICJkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n04.prod.us-east-1.postgun.com with SMTP id 6051ccdd1de5dd7b996a07ed (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 17 Mar 2021 09:33:17 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 4D4B8C43465; Wed, 17 Mar 2021 09:33:17 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: saiprakash.ranjan) by smtp.codeaurora.org (Postfix) with ESMTPSA id 7EB7DC433CA; Wed, 17 Mar 2021 09:33:16 +0000 (UTC) MIME-Version: 1.0 Date: Wed, 17 Mar 2021 15:03:16 +0530 From: Sai Prakash Ranjan To: Rob Clark Subject: Re: [PATCH 2/3] iommu/io-pgtable-arm: Add IOMMU_LLC page protection flag In-Reply-To: References: <3f589e7de3f9fa93e84c83420c5270c546a0c368.1610372717.git.saiprakash.ranjan@codeaurora.org> <20210129090516.GB3998@willie-the-truck> <5d23fce629323bcda71594010824aad0@codeaurora.org> <20210201111556.GA7172@willie-the-truck> <20210201182016.GA21629@jcrouse1-lnx.qualcomm.com> <7e9aade14d0b7f69285852ade4a5a9f4@codeaurora.org> <20210203214612.GB19847@willie-the-truck> Message-ID: X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Isaac J. Manjarres" , Will Deacon , Joerg Roedel , Akhil P Oommen , "\" , , Linux Kernel Mailing List , linux-arm-msm , freedreno , Kristian H Kristensen , Sean Paul , David Airlie , Daniel Vetter , dri-devel" , Jordan Crouse , Robin Murphy Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Rob, On 2021-03-16 22:46, Rob Clark wrote: ... >> > > >> > > When the GPU has a buffer mapped with IOMMU_LLC, is the buffer also mapped >> > > into the CPU and with what attributes? Rob said "writecombine for >> > > everything" -- does that mean ioremap_wc() / MEMREMAP_WC? >> > >> > Currently userspace asks for everything WC, so pgprot_writecombine() >> > >> > The kernel doesn't enforce this, but so far provides no UAPI to do >> > anything useful with non-coherent cached mappings (although there is >> > interest to support this) >> > >> >> btw, I'm looking at a benchmark (gl_driver2_off) where (after some >> other in-flight optimizations land) we end up bottlenecked on writing >> to WC cmdstream buffers. I assume in the current state, WC goes all >> the way to main memory rather than just to system cache? >> > > oh, I guess this (mentioned earlier in thread) is what I really want > for this benchmark: > > https://android-review.googlesource.com/c/kernel/common/+/1549097/3 > You can also check if the system cache lines are allocated for GPU or not with patch in https://crrev.com/c/2766723 With the above patch applied, cat /sys/kernel/debug/llcc_stats/llcc_scid_status The SCIDs for GPU are listed in include/linux/soc/qcom/llcc-qcom.h Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel