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=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED autolearn=ham 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 234DDC04AB5 for ; Tue, 4 Jun 2019 02:05:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ECE8F2581D for ; Tue, 4 Jun 2019 02:05:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726406AbfFDCFz (ORCPT ); Mon, 3 Jun 2019 22:05:55 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:44001 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726245AbfFDCFy (ORCPT ); Mon, 3 Jun 2019 22:05:54 -0400 X-UUID: 5629ac9e18844ae7ac5ca849e7c642eb-20190604 X-UUID: 5629ac9e18844ae7ac5ca849e7c642eb-20190604 Received: from mtkcas08.mediatek.inc [(172.21.101.126)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 2031812081; Tue, 04 Jun 2019 10:05:42 +0800 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkexhb02.mediatek.inc (172.21.101.103) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 4 Jun 2019 10:05:41 +0800 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkcas08.mediatek.inc (172.21.101.126) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 4 Jun 2019 10:05:40 +0800 Received: from [172.21.77.4] (172.21.77.4) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 4 Jun 2019 10:05:40 +0800 Message-ID: <1559613940.9975.0.camel@mtksdaap41> Subject: Re: [PATCH v4] gpu/drm: mediatek: call mtk_dsi_stop() after mtk_drm_crtc_atomic_disable() From: CK Hu To: Hsin-Yi Wang CC: , Philipp Zabel , David Airlie , Daniel Vetter , Matthias Brugger , , , Date: Tue, 4 Jun 2019 10:05:40 +0800 In-Reply-To: <20190530091847.90263-1-hsinyi@chromium.org> References: <20190530091847.90263-1-hsinyi@chromium.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Hsin-Yi: On Thu, 2019-05-30 at 17:18 +0800, Hsin-Yi Wang wrote: > mtk_dsi_stop() should be called after mtk_drm_crtc_atomic_disable(), which needs > ovl irq for drm_crtc_wait_one_vblank(), since after mtk_dsi_stop() is called, > ovl irq will be disabled. If drm_crtc_wait_one_vblank() is called after last > irq, it will timeout with this message: "vblank wait timed out on crtc 0". This > happens sometimes when turning off the screen. > > In drm_atomic_helper.c#disable_outputs(), > the calling sequence when turning off the screen is: > > 1. mtk_dsi_encoder_disable() > --> mtk_output_dsi_disable() > --> mtk_dsi_stop(); // sometimes make vblank timeout in atomic_disable > --> mtk_dsi_poweroff(); > 2. mtk_drm_crtc_atomic_disable() > --> drm_crtc_wait_one_vblank(); > ... > --> mtk_dsi_ddp_stop() > --> mtk_dsi_poweroff(); > > mtk_dsi_poweroff() has reference count design, change to make mtk_dsi_stop() > called in mtk_dsi_poweroff() when refcount is 0. Applied to mediatek-drm-fixes-5.2 [1], thanks. [1] https://github.com/ckhu-mediatek/linux.git-tags/commits/mediatek-drm-fixes-5.2 Regards, CK > > Fixes: 0707632b5bac ("drm/mediatek: update DSI sub driver flow for sending commands to panel") > Signed-off-by: Hsin-Yi Wang > --- > change log v3->v4: > * add comment in code. > --- > drivers/gpu/drm/mediatek/mtk_dsi.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c > index b00eb2d2e086..730594a91440 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > @@ -630,6 +630,15 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi) > if (--dsi->refcount != 0) > return; > > + /* > + * mtk_dsi_stop() and mtk_dsi_start() is asymmetric, since > + * mtk_dsi_stop() should be called after mtk_drm_crtc_atomic_disable(), > + * which needs irq for vblank, and mtk_dsi_stop() will disable irq. > + * mtk_dsi_start() needs to be called in mtk_output_dsi_enable(), > + * after dsi is fully set. > + */ > + mtk_dsi_stop(dsi); > + > if (!mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500)) { > if (dsi->panel) { > if (drm_panel_unprepare(dsi->panel)) { > @@ -696,7 +705,6 @@ static void mtk_output_dsi_disable(struct mtk_dsi *dsi) > } > } > > - mtk_dsi_stop(dsi); > mtk_dsi_poweroff(dsi); > > dsi->enabled = false;