From patchwork Sun Apr 10 06:15:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas De Marchi X-Patchwork-Id: 12808062 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 E116BC433EF for ; Sun, 10 Apr 2022 06:16:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D412F10F677; Sun, 10 Apr 2022 06:16:15 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5845410F5DF for ; Sun, 10 Apr 2022 06:16:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649571370; x=1681107370; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=8y+WA120XaOHVUVlx83cZSL7+iLMjX4AAMokyPE/J1o=; b=YyRCFBOXyJwqiV7ZN9qCoeCOxTWdrY8tLMIgii6rd5fZLUk2gdVEwTUf pKQsFauttqj1W5n6RuE+7dxTz/AiQJDKtXwY02oohBfSS80mR0eDFD9kH usuhTffpAWQJ/eLEjp/vS/mr54KdjcsJEAaiF3hEW/xfyG0GioybN6s8u d2NUQIIlJQIuMUVf4aU3vChyAC0EQbYVMu1Mopthyq57QCBjhYBG31pB6 bOXdDH23RrVhcS+kQkrLucZfx2OijeTFPl16cOAqFMwLGKJN2YyIWRE3h ZTgDdoXa1c72FZ/NUecir72qtt+4Yf9YD9xHE63FI6yK7JVYfKKL3HI6H g==; X-IronPort-AV: E=McAfee;i="6400,9594,10312"; a="348381061" X-IronPort-AV: E=Sophos;i="5.90,249,1643702400"; d="scan'208";a="348381061" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Apr 2022 23:16:08 -0700 X-IronPort-AV: E=Sophos;i="5.90,249,1643702400"; d="scan'208";a="571664015" Received: from lucas-s2600cw.jf.intel.com ([10.165.21.202]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Apr 2022 23:16:07 -0700 From: Lucas De Marchi To: intel-gfx@lists.freedesktop.org Date: Sat, 9 Apr 2022 23:15:36 -0700 Message-Id: <20220410061537.4187383-1-lucas.demarchi@intel.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915/dg2: Do not explode on phy calibration error X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lucas De Marchi Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" When the PHY fails on calibration we were previously skipping the ddi initialization. However the driver is not really prepared for that, ultimately leading to a NULL pointer dereference: [ 75.748348] i915 0000:03:00.0: [drm:intel_modeset_init_nogem [i915]] SNPS PHY A failed to calibrate; output will not be used. ... [ 75.750336] i915 0000:03:00.0: [drm:intel_modeset_setup_hw_state [i915]] [CRTC:80:pipe A] hw state readout: enabled ... ( no DDI A/PHY A ) [ 75.753080] i915 0000:03:00.0: [drm:intel_modeset_setup_hw_state [i915]] [ENCODER:235:DDI B/PHY B] hw state readout: disabled, pipe A [ 75.753164] i915 0000:03:00.0: [drm:intel_modeset_setup_hw_state [i915]] [ENCODER:245:DDI C/PHY C] hw state readout: disabled, pipe A ... [ 75.754425] i915 0000:03:00.0: [drm] *ERROR* crtc 80: Can't calculate constants, dotclock = 0! [ 75.765558] i915 0000:03:00.0: drm_WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)) [ 75.765569] WARNING: CPU: 5 PID: 1759 at drivers/gpu/drm/drm_vblank.c:728 drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x347/0x360 ... [ 75.781230] BUG: kernel NULL pointer dereference, address: 000000000000007c [ 75.788198] #PF: supervisor read access in kernel mode [ 75.793347] #PF: error_code(0x0000) - not-present page [ 75.798480] PGD 0 P4D 0 [ 75.801019] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 75.805377] CPU: 5 PID: 1759 Comm: modprobe Tainted: G W 5.18.0-rc1-demarchi+ #199 [ 75.827613] RIP: 0010:icl_aux_power_well_disable+0x3b/0x200 [i915] [ 75.833890] Code: 83 ec 30 65 48 8b 04 25 28 00 00 00 48 89 44 24 28 48 8b 06 0f b6 70 1c f6 40 20 04 8d 56 fa 0f 45 f2 e8 88 bd ff ff 48 89 ef <8b> 70 7c e8 ed 67 ff ff 48 89 ef 89 c6 e8 73 67 ff ff 84 c0 75 0a [ 75.852629] RSP: 0018:ffffc90003a7fb30 EFLAGS: 00010246 [ 75.857852] RAX: 0000000000000000 RBX: ffff8881145e8f10 RCX: 0000000000000000 [ 75.864978] RDX: ffff888115220840 RSI: 0000000000000000 RDI: ffff888115220000 [ 75.872106] RBP: ffff888115220000 R08: ffff88888effffe8 R09: 00000000fffdffff [ 75.879234] R10: ffff88888e200000 R11: ffff88888ed00000 R12: ffff8881145e8f10 [ 75.886363] R13: 0000000000000001 R14: ffff888115223240 R15: 0000000000000000 [ 75.893490] FS: 00007ff6e753a740(0000) GS:ffff88888f680000(0000) knlGS:0000000000000000 [ 75.901573] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 75.907313] CR2: 000000000000007c CR3: 00000001216a6001 CR4: 0000000000770ee0 [ 75.914446] PKRU: 55555554 [ 75.917153] Call Trace: [ 75.919603] [ 75.921709] intel_power_domains_sanitize_state+0x88/0xb0 [i915] [ 75.927814] intel_modeset_init_nogem+0x317/0xef0 [i915] [ 75.933205] i915_driver_probe+0x5f6/0xdf0 [i915] [ 75.937976] i915_pci_probe+0x51/0x1d0 [i915] We skip the initialization of PHY A, but later we try to find out what is the phy for that power well and dereference dig_port, which is NULL. Failing the PHY calibration could be left as a warning or error, like it was before commit b4eb76d82a0e ("drm/i915/dg2: Skip output init on PHY calibration failure"). However that often fails for outputs not being used, which would make the warning/error appear on systems that have no visible issues. Anyway, there is still a need to fix those failures, but that is left for later. Signed-off-by: Lucas De Marchi Reviewed-by: Matt Roper --- drivers/gpu/drm/i915/display/intel_ddi.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index cec578efc4bd..027cc4cc38d9 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -4300,9 +4300,8 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port) if (intel_phy_is_snps(dev_priv, phy) && dev_priv->snps_phy_failed_calibration & BIT(phy)) { drm_dbg_kms(&dev_priv->drm, - "SNPS PHY %c failed to calibrate; output will not be used.\n", + "SNPS PHY %c failed to calibrate, proceeding anyway\n", phy_name(phy)); - return; } dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);