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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 18DC1C433E6 for ; Mon, 6 Jul 2020 07:20:48 +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 DFC072073E for ; Mon, 6 Jul 2020 07:20:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="EjIuvl78" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DFC072073E 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 1556A6E321; Mon, 6 Jul 2020 07:19:55 +0000 (UTC) Received: from mail29.static.mailgun.info (mail29.static.mailgun.info [104.130.122.29]) by gabe.freedesktop.org (Postfix) with ESMTPS id 49C816EB2C for ; Fri, 3 Jul 2020 16:59:20 +0000 (UTC) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1593795560; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=+gnWJZLQFOi3Y3xgbq+Jj83g8jf7HMQgZHy7FN5ldrA=; b=EjIuvl78ZmKmI6Au48AVCGhtr+kNqmihYQTsyl8VqwR6K+ZEVikpy/b0aQyYItbco/D7Mhv3 M7kattnHUor2Z/HhH/nvTzHbZnSgQa8I1LX05DBq0OAvKsNnxaiCW/u3aZACJUkeQaUIMaG4 nC5e5MtgXo2N+RQyT3fejwFZpxI= X-Mailgun-Sending-Ip: 104.130.122.29 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 5eff63e6a3d8a447431620b8 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 03 Jul 2020 16:59:18 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 8AAAAC433A1; Fri, 3 Jul 2020 16:59:17 +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 6CB36C433C6; Fri, 3 Jul 2020 16:59:16 +0000 (UTC) MIME-Version: 1.0 Date: Fri, 03 Jul 2020 22:29:16 +0530 From: Sai Prakash Ranjan To: Rob Clark Subject: Re: [PATCHv3 7/7] drm/msm/a6xx: Add support for using system cache(LLC) In-Reply-To: References: <449a6544b10f0035d191ac52283198343187c153.1593344120.git.saiprakash.ranjan@codeaurora.org> <20200703133732.GD18953@willie-the-truck> Message-ID: X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 X-Mailman-Approved-At: Mon, 06 Jul 2020 07:19:18 +0000 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: Will Deacon , David Airlie , Sean Paul , Joerg Roedel , Linux Kernel Mailing List , dri-devel , Akhil P Oommen , Emil Velikov , "list@263.net:IOMMU DRIVERS , Joerg Roedel , " , Matthias Kaehlcke , "Kristian H . Kristensen" , linux-arm-msm , Stephen Boyd , freedreno , Sharat Masetty , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , 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" On 2020-07-03 21:34, Rob Clark wrote: > On Fri, Jul 3, 2020 at 7:53 AM Sai Prakash Ranjan > wrote: >> >> Hi Will, >> >> On 2020-07-03 19:07, Will Deacon wrote: >> > On Mon, Jun 29, 2020 at 09:22:50PM +0530, Sai Prakash Ranjan wrote: >> >> diff --git a/drivers/gpu/drm/msm/msm_iommu.c >> >> b/drivers/gpu/drm/msm/msm_iommu.c >> >> index f455c597f76d..bd1d58229cc2 100644 >> >> --- a/drivers/gpu/drm/msm/msm_iommu.c >> >> +++ b/drivers/gpu/drm/msm/msm_iommu.c >> >> @@ -218,6 +218,9 @@ static int msm_iommu_map(struct msm_mmu *mmu, >> >> uint64_t iova, >> >> iova |= GENMASK_ULL(63, 49); >> >> >> >> >> >> + if (mmu->features & MMU_FEATURE_USE_SYSTEM_CACHE) >> >> + prot |= IOMMU_SYS_CACHE_ONLY; >> > >> > Given that I think this is the only user of IOMMU_SYS_CACHE_ONLY, then >> > it >> > looks like it should actually be a property on the domain because we >> > never >> > need to configure it on a per-mapping basis within a domain, and >> > therefore >> > it shouldn't be exposed by the IOMMU API as a prot flag. >> > >> > Do you agree? >> > >> >> GPU being the only user is for now, but there are other clients which >> can use this. >> Plus how do we set the memory attributes if we do not expose this as >> prot flag? > > It does appear that the downstream kgsl driver sets this for basically > all mappings.. well there is some conditional stuff around > DOMAIN_ATTR_USE_LLC_NWA but it seems based on the property of the > domain. (Jordan may know more about what that is about.) But looks > like there are a lot of different paths into iommu_map in kgsl so I > might have missed something. > > Assuming there isn't some case where we specifically don't want to use > the system cache for some mapping, I think it could be a domain > attribute that sets an io_pgtable_cfg::quirks flag > Ok then we are good to remove unused sys cache prot flag which Will has posted. 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