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_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 D473FC4742C for ; Mon, 16 Nov 2020 17:49:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 997BD20B80 for ; Mon, 16 Nov 2020 17:49:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Xo+6RoUK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387632AbgKPRsq (ORCPT ); Mon, 16 Nov 2020 12:48:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733190AbgKPRsp (ORCPT ); Mon, 16 Nov 2020 12:48:45 -0500 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCBC7C0613CF; Mon, 16 Nov 2020 09:48:43 -0800 (PST) Received: by mail-wr1-x444.google.com with SMTP id r17so19728850wrw.1; Mon, 16 Nov 2020 09:48:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oo28y8CwbarIIHt9QVICKSL/cPf2jBzgOsxS9+pjqV4=; b=Xo+6RoUKW5EPAQ5AfiLMX2ZOBP3YtaRXNtMeaOx5Kz6LQeDbTNdN8Tn1drGDcfrXbC mPk13Xv0teQZptYrVKdoX4Wo9+81F0IAhppDl0rbxUZYifSBDn25uao5eQeQo1F2qh2o oDFsFeLhHS524Vtqx1v5iCCJ0CKyCSNVG917jK5sS0i0nGSSY43ASsqSX+k+7zleqUwP m2J84Jhrk0YOxQ22Cg7UdO7tOgwcWJJBKfgbfpM6wwxzC4Q2UsWXPFW+TpnUHVet2yv/ 91PQg079/9WnamlCea28HYMTRO6Pt3f6splsJ4ecRed2px63Gik6CAV0aQZU1XnWjgeZ gUJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oo28y8CwbarIIHt9QVICKSL/cPf2jBzgOsxS9+pjqV4=; b=AtRqJJlwNgVMOtmwuXDmik7Tf8n7zLzf58XyqNOjDaAi2KtgQv4dKTAYR83iaD1mHf gchDHncf5Ohu3x9KS42GsIGMjD5raSnUMRqfxSj44dwYMnT7y3hqhdcp5a3cqe3Nrayn vkh1IfQdE81jZ1NUjk8N9Rutp1txVesj9w8LIbVKmIbUXXTP35dWGNqiiex/EiyDgkBH GcX08sYZeUDYe0hvnpr6tsDLhTKgAOekfWcn+vYPCQ5xXROE6tbAZnA2to9jcWnu3F/a KkUC0OUsSU0aR4krxuEH4kOqf5FO38Y7I2MeXUfDpOkmfmVfsRpB/RedBVYQbsEud4dx p/nQ== X-Gm-Message-State: AOAM530hIOtCgPr5H0EIyrnK15wBxL+GIDMRH+x+ieRrlMO1GEBMu1Fl dnWCWwcLlpanX6dDfXAJHY4zAyjmMzBuGtRo739mmIgX99c= X-Google-Smtp-Source: ABdhPJwLUHRCNxP780S9wB4HTWCUx9z/UF/ZjtKuXyrKptvA/sOlIX/C0TT7KCOFIw7oMBBwToUFga8s7TvJdYI0jDU= X-Received: by 2002:adf:f04b:: with SMTP id t11mr19535784wro.147.1605548922581; Mon, 16 Nov 2020 09:48:42 -0800 (PST) MIME-Version: 1.0 References: <20201114151717.5369-1-jonathan@marek.ca> <20201114151717.5369-5-jonathan@marek.ca> <20201114162406.GC24411@lst.de> <50ddcadb-c630-2ef6-cdc4-724d9823fba7@marek.ca> <20201116173346.GA24173@lst.de> In-Reply-To: <20201116173346.GA24173@lst.de> From: Rob Clark Date: Mon, 16 Nov 2020 09:50:28 -0800 Message-ID: Subject: Re: [RESEND PATCH v2 4/5] drm/msm: add DRM_MSM_GEM_SYNC_CACHE for non-coherent cache maintenance To: Christoph Hellwig Cc: Jonathan Marek , freedreno , Sean Paul , David Airlie , Daniel Vetter , "open list:DRM DRIVER FOR MSM ADRENO GPU" , "open list:DRM DRIVER FOR MSM ADRENO GPU" , open list Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 16, 2020 at 9:33 AM Christoph Hellwig wrote: > > On Sat, Nov 14, 2020 at 03:07:20PM -0500, Jonathan Marek wrote: > > qcom's vulkan driver has nonCoherentAtomSize=1, and it looks like > > dma_sync_single_for_cpu() does deal in some way with the partial cache line > > case, although I'm not sure that means we can have a nonCoherentAtomSize=1. > > No, it doesn't. You need to ensure ownership is managed at > dma_get_cache_alignment() granularity. my guess is nonCoherentAtomSize=1 only works in the case of cache coherent buffers BR, -R