From patchwork Tue Jul 3 07:50:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Brezillon X-Patchwork-Id: 10503369 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 92EBC601D3 for ; Tue, 3 Jul 2018 07:50:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8833228A9C for ; Tue, 3 Jul 2018 07:50:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 86B7D28AFC; Tue, 3 Jul 2018 07:50:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0FDD228AE0 for ; Tue, 3 Jul 2018 07:50:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C99F56E596; Tue, 3 Jul 2018 07:50:30 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.bootlin.com (mail.bootlin.com [62.4.15.54]) by gabe.freedesktop.org (Postfix) with ESMTP id 579CA6E579 for ; Tue, 3 Jul 2018 07:50:27 +0000 (UTC) Received: by mail.bootlin.com (Postfix, from userid 110) id 9138E208B3; Tue, 3 Jul 2018 09:50:25 +0200 (CEST) Received: from localhost.localdomain (AAubervilliers-681-1-39-106.w90-88.abo.wanadoo.fr [90.88.158.106]) by mail.bootlin.com (Postfix) with ESMTPSA id 54F4D2079F; Tue, 3 Jul 2018 09:50:25 +0200 (CEST) From: Boris Brezillon To: David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org Subject: [PATCH v4 5/8] drm/crtc: Add a generic infrastructure to fake VBLANK events Date: Tue, 3 Jul 2018 09:50:19 +0200 Message-Id: <20180703075022.15138-6-boris.brezillon@bootlin.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20180703075022.15138-1-boris.brezillon@bootlin.com> References: <20180703075022.15138-1-boris.brezillon@bootlin.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Liviu Dudau , Dan Carpenter , Boris Brezillon MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP In some cases CRTCs are active but are not able to generating events, at least not at every frame at it's expected to. This is typically the case when the CRTC is feeding a writeback connector that has no job queued. In this situation the CRTC is usually stopped until a new job is queued, and this can lead to timeouts when part of the pipeline is updated but no new jobs are queued to the active writeback connector. In order to solve that, we add a ->no_vblank flag to drm_crtc_state and ask the CRTC drivers to set it to true when they know they're not able to generate VBLANK events. The core drm_atomic_helper_fake_vblank() helper can then be used to fake VBLANKs at commit time. Signed-off-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Daniel Vetter --- Changes in v4: - None Changes in v3: - Use inline doc for @no_vblank - Fix drm_atomic_helper_fake_vblank() to only check new_crtc_state->no_vblank - Add R-b tags Changes in v2: - New patch --- drivers/gpu/drm/drm_atomic_helper.c | 39 +++++++++++++++++++++++++++++++++++++ include/drm/drm_atomic_helper.h | 1 + include/drm/drm_crtc.h | 23 ++++++++++++++++++++++ 3 files changed, 63 insertions(+) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 5026096d0b52..c8d1633ebc00 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -2053,6 +2053,45 @@ void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *old_state) } EXPORT_SYMBOL(drm_atomic_helper_wait_for_dependencies); +/** + * drm_atomic_helper_fake_vblank - fake VBLANK events if needed + * @old_state: atomic state object with old state structures + * + * This function walks all CRTCs and fake VBLANK events on those with + * &drm_crtc_state.no_vblank set to true and &drm_crtc_state.event != NULL. + * The primary use of this function is writeback connectors working in oneshot + * mode and faking VBLANK events. In this case they only fake the VBLANK event + * when a job is queued, and any change to the pipeline that does not touch the + * connector is leading to timeouts when calling + * drm_atomic_helper_wait_for_vblanks() or + * drm_atomic_helper_wait_for_flip_done(). + * + * This is part of the atomic helper support for nonblocking commits, see + * drm_atomic_helper_setup_commit() for an overview. + */ +void drm_atomic_helper_fake_vblank(struct drm_atomic_state *old_state) +{ + struct drm_crtc_state *new_crtc_state; + struct drm_crtc *crtc; + int i; + + for_each_new_crtc_in_state(old_state, crtc, new_crtc_state, i) { + unsigned long flags; + + if (!new_crtc_state->no_vblank) + continue; + + spin_lock_irqsave(&old_state->dev->event_lock, flags); + if (new_crtc_state->event) { + drm_crtc_send_vblank_event(crtc, + new_crtc_state->event); + new_crtc_state->event = NULL; + } + spin_unlock_irqrestore(&old_state->dev->event_lock, flags); + } +} +EXPORT_SYMBOL(drm_atomic_helper_fake_vblank); + /** * drm_atomic_helper_commit_hw_done - setup possible nonblocking commit * @old_state: atomic state object with old state structures diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h index 26aaba58d6ce..99e2a5297c69 100644 --- a/include/drm/drm_atomic_helper.h +++ b/include/drm/drm_atomic_helper.h @@ -100,6 +100,7 @@ int __must_check drm_atomic_helper_swap_state(struct drm_atomic_state *state, int drm_atomic_helper_setup_commit(struct drm_atomic_state *state, bool nonblock); void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *state); +void drm_atomic_helper_fake_vblank(struct drm_atomic_state *state); void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *state); void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *state); diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 23eddbccab10..17f4f93340b8 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -119,6 +119,29 @@ struct drm_crtc_state { bool zpos_changed : 1; bool color_mgmt_changed : 1; + /** + * @no_vblank: + * + * Reflects the ability of a CRTC to send VBLANK events. This state + * usually depends on the pipeline configuration, and the main usuage + * is CRTCs feeding a writeback connector operating in oneshot mode. + * In this case the VBLANK event is only generated when a job is queued + * to the writeback connector, and we want the core to fake VBLANK + * events when this part of the pipeline hasn't changed but others had + * or when the CRTC and connectors are being disabled. + * + * __drm_atomic_helper_crtc_duplicate_state() will not reset the value + * from the current state, the CRTC driver is then responsible for + * updating this field when needed. + * + * Note that the combination of &drm_crtc_state.event == NULL and + * &drm_crtc_state.no_blank == true is valid and usually used when the + * writeback connector attached to the CRTC has a new job queued. In + * this case the driver will send the VBLANK event on its own when the + * writeback job is complete. + */ + bool no_vblank : 1; + /* attached planes bitmask: * WARNING: transitional helpers do not maintain plane_mask so * drivers not converted over to atomic helpers should not rely