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=-2.7 required=3.0 tests=BAYES_00,DATE_IN_PAST_12_24, 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 665BFC433DB for ; Fri, 12 Mar 2021 11:53:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 450F864FE0 for ; Fri, 12 Mar 2021 11:53:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231707AbhCLLwk convert rfc822-to-8bit (ORCPT ); Fri, 12 Mar 2021 06:52:40 -0500 Received: from aposti.net ([89.234.176.197]:38676 "EHLO aposti.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231423AbhCLLwJ (ORCPT ); Fri, 12 Mar 2021 06:52:09 -0500 Date: Thu, 11 Mar 2021 12:33:31 +0000 From: Paul Cercueil Subject: Re: [PATCH v2 4/5] drm: Add and export function drm_gem_cma_sync_data To: Christoph Hellwig Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Sam Ravnborg , od@zcrc.me, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org Message-Id: In-Reply-To: <20210311122846.GC1739082@infradead.org> References: <20210307202835.253907-1-paul@crapouillou.net> <20210307202835.253907-5-paul@crapouillou.net> <20210311122846.GC1739082@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le jeu. 11 mars 2021 à 12:28, Christoph Hellwig a écrit : > On Sun, Mar 07, 2021 at 08:28:34PM +0000, Paul Cercueil wrote: >> + drm_atomic_for_each_plane_damage(&iter, &clip) { >> + for (i = 0; i < finfo->num_planes; i++) { >> + daddr = drm_fb_cma_get_gem_addr(state->fb, state, i); >> + >> + /* Ignore x1/x2 values, invalidate complete lines */ >> + offset = clip.y1 * state->fb->pitches[i]; >> + >> + dma_sync_single_for_device(dev, daddr + offset, >> + (clip.y2 - clip.y1) * state->fb->pitches[i], >> + DMA_TO_DEVICE); > > Are these helpers only ever used to transfer data to the device and > never from it? If so please clearly document that. Yes. In the DRM world, are there cases where we transfer data from the device? I assume these cases are handled by v4l2 instead. -Paul