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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8538FE77188 for ; Tue, 14 Jan 2025 12:55:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E6BD610E288; Tue, 14 Jan 2025 12:55:04 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="YKk6ueqC"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id A0CAE10E288 for ; Tue, 14 Jan 2025 12:55:03 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 150491BF206; Tue, 14 Jan 2025 12:54:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1736859302; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GetRem5oPol4EWNwAaMciHaBSzuYs3v6WipDaRzEtS4=; b=YKk6ueqCjvimBAE8Su47qnAChzki9AcjKkB75GVX/G6qZ2cxAkaBovqgWZKQx35iScUS5D vk1FaLHJhijV6w0r45WASGJGgOXumlK5Scz//Ua8e/moO54Tih+0cPTGXWg3Bie6bCLKpy /ymGtgtxIpcu78HIjMpWTjMzDtUasr4Inqmgx1iOE2cP30+qOU+9E7jtl0G857MG3EW+WO 9KhHeZZSmgooXee3HyoWK3T/cCW1Y4JmXsdiCl5Z/lmzP3esV4FqOW8UIysmvLKLgolrAF 7dR5H4cGnugiNKwKEdwcAaJCSHxycpckcpE2YcCM0hJEvAqyexqU7LapJzuPgw== Date: Tue, 14 Jan 2025 13:54:56 +0100 From: Herve Codina To: Maxime Ripard Cc: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Simona Vetter , Maarten Lankhorst , Thomas Zimmermann , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Marek Vasut , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Louis Chauvet , Luca Ceresoli , Thomas Petazzoni Subject: Re: [PATCH v3 3/3] drm: bridge: ti-sn65dsi83: Add error recovery mechanism Message-ID: <20250114135456.5366eb2a@bootlin.com> In-Reply-To: <20250114-juicy-authentic-mushroom-cfcdfb@houat> References: <20250108101907.410456-1-herve.codina@bootlin.com> <20250108101907.410456-4-herve.codina@bootlin.com> <20250114-juicy-authentic-mushroom-cfcdfb@houat> Organization: Bootlin X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-GND-Sasl: herve.codina@bootlin.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Maxime, On Tue, 14 Jan 2025 08:40:51 +0100 Maxime Ripard wrote: ... > > > > +static int sn65dsi83_reset_pipe(struct sn65dsi83 *sn65dsi83) > > +{ > > + struct drm_atomic_state *state = ERR_PTR(-EINVAL); > > + struct drm_device *dev = sn65dsi83->bridge.dev; > > + struct drm_connector_state *connector_state; > > + struct drm_modeset_acquire_ctx ctx; > > + struct drm_connector *connector; > > + int err; > > + > > + /* > > + * Reset active outputs of the related CRTC. > > + * > > + * This way, drm core will reconfigure each components in the CRTC > > + * outputs path. In our case, this will force the previous component to > > + * go back in LP11 mode and so allow the reconfiguration of SN64DSI83 > > + * bridge. > > + * > > + * Keep the lock during the whole operation to be atomic. > > + */ > > + > > + DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, err); > > + > > + state = drm_atomic_helper_duplicate_state(dev, &ctx); > > + if (IS_ERR(state)) { > > + err = PTR_ERR(state); > > + goto unlock; > > + } > > No, you must not allocate a new state for this, you need to reuse the > existing state. You'll find it in bridge->base.state->state. Thanks for pointing that. I didn't know about bridge->base.state->state. I will use that if using the state is still relevant (see next comment). > > > + state->acquire_ctx = &ctx; > > + > > + connector = drm_atomic_get_old_connector_for_encoder(state, > > + sn65dsi83->bridge.encoder); > > + if (!connector) { > > + err = -EINVAL; > > + goto unlock; > > + } > > + > > + connector_state = drm_atomic_get_connector_state(state, connector); > > + if (IS_ERR(connector_state)) { > > + err = PTR_ERR(connector_state); > > + goto unlock; > > + } > > + > > + err = drm_atomic_helper_reset_pipe(connector_state->crtc, &ctx); > > + if (err < 0) > > + goto unlock; > > And you'll find the crtc in bridge->encoder->crtc. I am a bit confused. I looked at the drm_encoder structure [1] and the crtc field available in this structure should not be used by atomic drivers. They should rely on &drm_connector_state.crtc. In my case, I have the feeling that I should get the ctrc from the current state (i.e. bridge->base.state->state) using the sequence provided in this current patch: Retrieve the connector with drm_atomic_get_old_connector_for_encoder() Retrieve the connector state with drm_atomic_get_connector_state() but you pointed out the bridge->encoder->crtc field. Should I use this field or use the &drm_connector_state.crtc with the drm connector state retrieved from bridge->base.state->state using the proposed sequence? [1] https://elixir.bootlin.com/linux/v6.13-rc1/source/include/drm/drm_encoder.h#L180 Best regards, Hervé