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 3D66FCCD1BF for ; Tue, 28 Oct 2025 16:38:33 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0215210E609; Tue, 28 Oct 2025 16:38:32 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="mIO/Jbmk"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 22AC710E605; Tue, 28 Oct 2025 16:38:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1761669511; x=1793205511; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=NBKNVxKzSchoFsDQZ+CIAYYpBzslSrxebBnbGoE2Ebs=; b=mIO/JbmkM7zLnCXwRPRMn2fiy2Lm/csMDR5xFEZagdKNkChVkJGkdE0d dgyKKqXpHWOgS09SfHRwVz2GfUw4nBghq5BRDdMRUEez5FJ3RlMojpK7E 1tLsqHLWER9yXj7YVlez895ffCl9nKUNg++njfu1uqBgwMAURcHP5zjV6 z1DCK9dXmHprgmUEKYPakT1xmD/ilbfCyA/zbqDY7np3JCja2F9YFG4PT JBK3Vx9D2Efkjxvfsq1gWuA5F12q1CHEcVboCO56ogZ1zqfYY0FDhefe2 Ljs/QeLQT1utuhv3jPbM26UJTjLaMNqS2EnGIgxxrfgrAGNIq3J8p3OAC w==; X-CSE-ConnectionGUID: kPHM8l1QRtqKzCyBdwvvDQ== X-CSE-MsgGUID: ak860GngTLWUXiR9xingKw== X-IronPort-AV: E=McAfee;i="6800,10657,11586"; a="67418556" X-IronPort-AV: E=Sophos;i="6.19,261,1754982000"; d="scan'208";a="67418556" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Oct 2025 09:38:30 -0700 X-CSE-ConnectionGUID: k4E1ZHFsRnmCv3mGZ+1Esw== X-CSE-MsgGUID: V/hE/SbzSviboF6X9SySvg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,261,1754982000"; d="scan'208";a="216277329" Received: from egrumbac-mobl6.ger.corp.intel.com (HELO localhost) ([10.245.244.169]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Oct 2025 09:38:28 -0700 Date: Tue, 28 Oct 2025 18:38:26 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Jani Nikula Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Subject: Re: [PATCH 1/2] drm/i915/dsi: log send packet sequence errors Message-ID: References: <20251028155712.1824565-1-jani.nikula@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20251028155712.1824565-1-jani.nikula@intel.com> X-Patchwork-Hint: comment Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Tue, Oct 28, 2025 at 05:57:11PM +0200, Jani Nikula wrote: > We might be getting send packet sequence errors and never know. Log > them. > > Signed-off-by: Jani Nikula > --- > drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 24 ++++++++++++-------- > 1 file changed, 15 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c > index 23402408e172..748e5462bd95 100644 > --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c > +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c > @@ -106,6 +106,7 @@ static const u8 *mipi_exec_send_packet(struct intel_dsi *intel_dsi, > u8 type, flags, seq_port; > u16 len; > enum port port; > + ssize_t ret; > > drm_dbg_kms(display->drm, "\n"); > > @@ -138,36 +139,41 @@ static const u8 *mipi_exec_send_packet(struct intel_dsi *intel_dsi, > > switch (type) { > case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM: > - mipi_dsi_generic_write(dsi_device, NULL, 0); > + ret = mipi_dsi_generic_write(dsi_device, NULL, 0); > break; > case MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM: > - mipi_dsi_generic_write(dsi_device, data, 1); > + ret = mipi_dsi_generic_write(dsi_device, data, 1); > break; > case MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM: > - mipi_dsi_generic_write(dsi_device, data, 2); > + ret = mipi_dsi_generic_write(dsi_device, data, 2); > break; > case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM: > case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM: > case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM: > - drm_dbg_kms(display->drm, "Generic Read not yet implemented or used\n"); > + ret = -EOPNOTSUPP; > break; > case MIPI_DSI_GENERIC_LONG_WRITE: > - mipi_dsi_generic_write(dsi_device, data, len); > + ret = mipi_dsi_generic_write(dsi_device, data, len); > break; > case MIPI_DSI_DCS_SHORT_WRITE: > - mipi_dsi_dcs_write_buffer(dsi_device, data, 1); > + ret = mipi_dsi_dcs_write_buffer(dsi_device, data, 1); > break; > case MIPI_DSI_DCS_SHORT_WRITE_PARAM: > - mipi_dsi_dcs_write_buffer(dsi_device, data, 2); > + ret = mipi_dsi_dcs_write_buffer(dsi_device, data, 2); > break; > case MIPI_DSI_DCS_READ: > - drm_dbg_kms(display->drm, "DCS Read not yet implemented or used\n"); > + ret = -EOPNOTSUPP; > break; > case MIPI_DSI_DCS_LONG_WRITE: > - mipi_dsi_dcs_write_buffer(dsi_device, data, len); > + ret = mipi_dsi_dcs_write_buffer(dsi_device, data, len); > break; > } > > + if (ret == -EOPNOTSUPP) Do we know that the write functions never return this value? > + drm_dbg_kms(display->drm, "DSI read not supported\n"); Is there a reason you didn't make this a drm_err() as well? We also have other debug messages related to unimplemented/unknown sequences/etc that I think should all be drm_err(). Otherwise we'll never find out if they're needed or not. > + else if (ret < 0) > + drm_err(display->drm, "DSI write failed with %pe\n", ERR_PTR(ret)); > + > if (DISPLAY_VER(display) < 11) > vlv_dsi_wait_for_fifo_empty(intel_dsi, port); > > -- > 2.47.3 -- Ville Syrjälä Intel