From mboxrd@z Thu Jan 1 00:00:00 1970 From: CK Hu Subject: Re: [RFC 2/3] drm/mediatek: add support for Mediatek SoC MT2701 Date: Fri, 13 May 2016 11:59:16 +0800 Message-ID: <1463111956.12239.15.camel@mtksdaap41> References: <1463053795-55455-1-git-send-email-yt.shen@mediatek.com> <1463053795-55455-3-git-send-email-yt.shen@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1463053795-55455-3-git-send-email-yt.shen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: yt.shen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org Cc: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Philipp Zabel , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Russell King , David Airlie , Matthias Brugger , Mao Huang , Bibby Hsieh , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, srv_heupstream-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, Sascha Hauer List-Id: devicetree@vger.kernel.org Hi, YT: On Thu, 2016-05-12 at 19:49 +0800, yt.shen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org wrote: > From: YT Shen > > This patch add support for the Mediatek MT2701 DISP subsystem. > There is only one OVL engine in MT2701, and we have shadow > register support here. > > Signed-off-by: YT Shen > --- > @@ -385,12 +422,16 @@ static void mtk_drm_crtc_atomic_begin(struct drm_crtc *crtc, > mtk_crtc->event = state->base.event; > state->base.event = NULL; > } > + > + if (priv->data->shadow_register) > + mtk_disp_mutex_acquire(mtk_crtc->mutex); > } > > @@ -409,6 +450,11 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc, > } > if (pending_planes) > mtk_crtc->pending_planes = true; > + > + if (priv->data->shadow_register) { > + mtk_crtc_ddp_config(crtc); > + mtk_disp_mutex_release(mtk_crtc->mutex); > + } > } > I think it's better to call mtk_disp_mutex_acquire() and mtk_disp_mutex_release() as near as possible to prevent mutex locked for a long time. All HW register access of this atomic setting is in mtk_crtc_ddp_config(), so it's better to move mtk_disp_mutex_acquire() just before mtk_crtc_ddp_config(). Regards, CK -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html