From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933511AbcCOBap (ORCPT ); Mon, 14 Mar 2016 21:30:45 -0400 Received: from regular1.263xmail.com ([211.150.99.138]:59410 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751003AbcCOBam (ORCPT ); Mon, 14 Mar 2016 21:30:42 -0400 X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED: 0 X-RL-SENDER: mark.yao@rock-chips.com X-FST-TO: xw@rock-chips.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: mark.yao@rock-chips.com X-UNIQUE-TAG: X-DNS-TYPE: 0 Message-ID: <56E765AE.1000606@rock-chips.com> Date: Tue, 15 Mar 2016 09:30:22 +0800 From: Mark yao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Tomeu Vizoso CC: =?UTF-8?B?SGVpa28gU3TDvGJuZXI=?= , Boris BREZILLON , David Airlie , Rob Clark , Daniel Vetter , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Randy Dunlap , Grant Likely , Greg Kroah-Hartman , John Stultz , Rom Lemarchand , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-api@vger.kernel.org" , "open list:ARM/Rockchip SoC..." , Douglas Anderson , =?UTF-8?B?U3TDqXBoYW5lIE1hcmNoZXNpbg==?= , dbehr@chromium.org, Olof Johansson , Daniel Kurtz , Eddie Cai , xxm@rock-chips.com, Tao Huang , Kever Yang , yxj@rock-chips.com, xw@rock-chips.com Subject: Re: [PATCH v15 1/3] drm: rockchip: Add basic drm driver References: <1417511600-7054-1-git-send-email-mark.yao@rock-chips.com> <1417511739-7141-1-git-send-email-mark.yao@rock-chips.com> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016年03月14日 21:35, Tomeu Vizoso wrote: > On 2 December 2014 at 10:15, Mark Yao wrote: >> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c >> new file mode 100644 >> index 0000000..e7ca25b >> --- /dev/null >> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c >> @@ -0,0 +1,1455 @@ > ... >> +static bool vop_crtc_mode_fixup(struct drm_crtc *crtc, >> + const struct drm_display_mode *mode, >> + struct drm_display_mode *adjusted_mode) >> +{ >> + if (adjusted_mode->htotal == 0 || adjusted_mode->vtotal == 0) >> + return false; > Hi Mark, > > what's the rationale for this? > > Disabling a CRTC as in [0] will cause mode_fixup() to be called with > an empty mode, failing that test. > > Removing the check seems to get things working fine for a short while, > but a later modeset invariably gets the VOP to hang (as reported by > [1]). > > Do you know why that check was put in place and what exactly could be > causing the hw to hang? > > [0] https://cgit.freedesktop.org/xorg/app/intel-gpu-tools/tree/lib/igt_kms.c#n1616 > [1] https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/rockchip/rockchip_drm_vop.c#n873 > > Thanks, > > Tomeu > Hi Tomeu Just thinking that "adjusted_mode->htotal == 0 || adjusted_mode->vtotal == 0" is not a good mode for vop. And you said VOP hang, only WARN_ON error message? or system hang, die? I think maybe crtc disable too fast, vblank is off, then no one can feed the wait_update_complete. Can you test it again with following patch? drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -503,6 +503,8 @@ static void vop_crtc_disable(struct drm_crtc *crtc) if (!vop->is_enabled) return; + vop_crtc_wait_for_update(crtc); + drm_crtc_vblank_off(crtc); Thanks. -- Ｍark Yao