From patchwork Fri Jul 21 09:41:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomi Valkeinen X-Patchwork-Id: 13321720 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 15067EB64DC for ; Fri, 21 Jul 2023 09:42:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2861910E641; Fri, 21 Jul 2023 09:42:20 +0000 (UTC) Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by gabe.freedesktop.org (Postfix) with ESMTPS id D44FB10E643 for ; Fri, 21 Jul 2023 09:42:18 +0000 (UTC) Received: from [127.0.1.1] (91-154-35-171.elisa-laajakaista.fi [91.154.35.171]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id ED3C52F5E; Fri, 21 Jul 2023 11:41:20 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1689932481; bh=cNkl06QQHpvODOS+NcyjyJrtUpAGoum7uDoGdQ4v5oM=; h=From:Date:Subject:To:Cc:From; b=oG+GCAZvk/7E4PKI49WAqK0Txl/XPwdEHjLiMWDlLIc1YWJeQWPFnj8d3/MhRPywj EqIIl8oc23WpAsnpNeO8IU3T7tJJAN9WU/bT2QB8z4JwgOrxlrTRUXrbYmVoi5f+EI H+5gSOzbbrdPC9jw6DsPOY+O4X67pgRR0UqNGok0= From: Tomi Valkeinen Date: Fri, 21 Jul 2023 12:41:49 +0300 Subject: [PATCH] drm/bridge: Add debugfs print for bridge chains MIME-Version: 1.0 Message-Id: <20230721-drm-bridge-chain-debugfs-v1-1-8614ff7e890d@ideasonboard.com> X-B4-Tracking: v=1; b=H4sIANxSumQC/x2MQQqAMAwEvyI5G2gjIvgV8WBtqjlYJUURxL8bP A47Ow8UVuECffWA8iVF9mzg6wrmdcoLo0RjIEeN68hj1A2DSrTFBMkYOZxLKuhCmH1LlNpuArs fyknuPz2M7/sB66l4eWoAAAA= To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Francesco Dolcini , Aradhya Bhatia X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=4407; i=tomi.valkeinen@ideasonboard.com; h=from:subject:message-id; bh=cNkl06QQHpvODOS+NcyjyJrtUpAGoum7uDoGdQ4v5oM=; b=owEBbQKS/ZANAwAIAfo9qoy8lh71AcsmYgBkulL3/1oxZDXSy2KXI3/n4Ihjp95Gkuy5lrimi SLm6s6nQmSJAjMEAAEIAB0WIQTEOAw+ll79gQef86f6PaqMvJYe9QUCZLpS9wAKCRD6PaqMvJYe 9b/lD/4vm9Td3Avl7pKylPBLSvKEq6KJ/GlYvERTWzWXNl0eHg0VbaYyXDIAZOJyJBRtvFanKsW B0DdiDHr3OdWAE+4NvAy4IyOQwrR121WYgfPPFuK9GdxCVoEaYmQW4EZ6yQ/iOxknT3vLEDWLr9 c3lxhkMst8jL5N7jkocg39agZ7V/UpiAzJm63WSjRMP6w9NaKBa6heFcipEBIexQKUoHnRmNPo6 pwx+xxL1kSDkQH2dhZ2/AdyExWQ6RVYMFRQbvNRFr6HFVtFBCWGY0R90z9stTeFyVhpV7qUGfo+ awF4JpAX7/uOY/cm+QYR7GNUPBocoWuuqQ7V9LZj4wEWVsJpFjovXeAuGNP9y5Y4hhMzXjmVBhL cYWb16j0RwftAnQ273fH2VXWfn1zvtnhxYuUKDVcFhACdIvtzoXAATuH+CiI6LtmATS7nlCCx76 31aonf3pWxb+cMQIvNQYy544LKYXk6JbehUGj09vZHH46tBnm8r2e6TPVGoMNkWdXTuTT+q5DSP jH2Y8UFg3rdc8Fw/A26L/1eJXuUx4oG7Ad4MV9iODKU4r1Vb0Rel/o9Qh3mWGM25NJ1sSpmuNwK I729ds+lxDQgRi/xP+CdyxiaH7EGvg6G8GCOer0Bywpnq4KVUdf2sre32Rg3LnWDnyDm866TYOi LHAqvD7LEyxrwCg== X-Developer-Key: i=tomi.valkeinen@ideasonboard.com; a=openpgp; fpr=C4380C3E965EFD81079FF3A7FA3DAA8CBC961EF5 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: , Cc: Tomi Valkeinen , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" DRM bridges are not visible to the userspace and it may not be immediately clear if the chain is somehow constructed incorrectly. I have had two separate instances of a bridge driver failing to do a drm_bridge_attach() call, resulting in the bridge connector not being part of the chain. In some situations this doesn't seem to cause issues, but it will if DRM_BRIDGE_ATTACH_NO_CONNECTOR flag is used. Add a debugfs file to print the bridge chains. For me, on this TI AM62 based platform, I get the following output: encoder[39] bridge[0] type: 0, ops: 0x0 bridge[1] type: 0, ops: 0x0, OF: /bus@f0000/i2c@20000000/dsi@e:toshiba,tc358778 bridge[2] type: 0, ops: 0x3, OF: /bus@f0000/i2c@20010000/hdmi@48:lontium,lt8912b bridge[3] type: 11, ops: 0x7, OF: /hdmi-connector:hdmi-connector Signed-off-by: Tomi Valkeinen --- drivers/gpu/drm/drm_bridge.c | 48 +++++++++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_debugfs.c | 3 +++ include/drm/drm_bridge.h | 5 +++++ 3 files changed, 56 insertions(+) --- base-commit: c7a472297169156252a50d76965eb36b081186e2 change-id: 20230721-drm-bridge-chain-debugfs-0bbc1522f57a Best regards, diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index c3d69af02e79..da3205aaed6b 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -27,8 +27,10 @@ #include #include +#include #include #include +#include #include #include @@ -1345,6 +1347,52 @@ struct drm_bridge *of_drm_find_bridge(struct device_node *np) EXPORT_SYMBOL(of_drm_find_bridge); #endif +#ifdef CONFIG_DEBUG_FS +static int drm_bridge_chains_info(struct seq_file *m, void *data) +{ + struct drm_debugfs_entry *entry = m->private; + struct drm_device *dev = entry->dev; + struct drm_printer p = drm_seq_file_printer(m); + struct drm_mode_config *config = &dev->mode_config; + struct drm_encoder *encoder; + unsigned int bridge_idx = 0; + + list_for_each_entry(encoder, &config->encoder_list, head) { + struct drm_bridge *bridge; + + drm_printf(&p, "encoder[%u]\n", encoder->base.id); + + bridge = drm_bridge_chain_get_first_bridge(encoder); + + while (bridge) { + drm_printf(&p, "\tbridge[%u] type: %u, ops: %#x", + bridge_idx, bridge->type, bridge->ops); + + if (bridge->of_node) + drm_printf(&p, ", OF: %pOFfc", bridge->of_node); + + drm_printf(&p, "\n"); + + bridge_idx++; + bridge = drm_bridge_get_next_bridge(bridge); + } + } + + return 0; +} + +/* any use in debugfs files to dump individual planes/crtc/etc? */ +static const struct drm_debugfs_info drm_bridge_debugfs_list[] = { + {"bridge_chains", drm_bridge_chains_info, 0}, +}; + +void drm_bridge_debugfs_init(struct drm_minor *minor) +{ + drm_debugfs_add_files(minor->dev, drm_bridge_debugfs_list, + ARRAY_SIZE(drm_bridge_debugfs_list)); +} +#endif + MODULE_AUTHOR("Ajay Kumar "); MODULE_DESCRIPTION("DRM bridge infrastructure"); MODULE_LICENSE("GPL and additional rights"); diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index c90dbcffa0dc..3e89559d68cd 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -31,6 +31,7 @@ #include #include +#include #include #include #include @@ -272,6 +273,8 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id, drm_debugfs_add_files(minor->dev, drm_debugfs_list, DRM_DEBUGFS_ENTRIES); + drm_bridge_debugfs_init(minor); + if (drm_drv_uses_atomic_modeset(dev)) { drm_atomic_debugfs_init(minor); } diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index bf964cdfb330..60dbee6bd1e6 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -949,4 +949,9 @@ static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, } #endif +#ifdef CONFIG_DEBUG_FS +struct drm_minor; +void drm_bridge_debugfs_init(struct drm_minor *minor); +#endif + #endif