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 00A45D3EE75 for ; Thu, 22 Jan 2026 15:29:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8EAA610E9DA; Thu, 22 Jan 2026 15:29:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="WC8fUOZA"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.14]) by gabe.freedesktop.org (Postfix) with ESMTPS id A340B10E9DA; Thu, 22 Jan 2026 15:29:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1769095794; x=1800631794; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=JkblPzBgZ0t6rExOlSwgXZ2AdokanDylxTcU33/BQlc=; b=WC8fUOZABw7XFMHIDk8Qi5ro0mN7OPw9sVeEgtuKpzWI5i8fn3JaD9+i JF+9NTytkclUtt2R+ZCFD5M7CjYQVdKtoo6iWTbm6Rpy8OYvhtyF5AJjP hCov0kPj67cQ2u63f+7Y6y3q1e/NXB1mCL0HMhYd7li/oi3Z+7imEglbd RT14OceeM9dwhicWnq8iJll/wkSumBFNyUl3Q8CMidi8PaucHMySEmSPc btw5kXAoZ4I4t1DGbbNOPmd0pYWUQtSevlApMKhOGLDM5JjLNDBwOAs1T zsL72AEd8NkoD48eMo1twjhzkP0D7LLHfR7hvpS0aV4rjtaH10Cea1Zu3 w==; X-CSE-ConnectionGUID: j5aU7XmKRCSGCS3zLGfpKQ== X-CSE-MsgGUID: wVLbzpteSeqykL9P3Bu+KQ== X-IronPort-AV: E=McAfee;i="6800,10657,11679"; a="74193447" X-IronPort-AV: E=Sophos;i="6.21,246,1763452800"; d="scan'208";a="74193447" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jan 2026 07:29:53 -0800 X-CSE-ConnectionGUID: Y6kmbdWpSeqgqrnw9MZOQg== X-CSE-MsgGUID: inNCecYBSdSnQgWeBBRDgQ== X-ExtLoop1: 1 Received: from slindbla-desk.ger.corp.intel.com (HELO localhost) ([10.245.246.192]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jan 2026 07:29:49 -0800 From: Jani Nikula To: Juasheem Sultan , intel-gfx@lists.freedesktop.org, intel_xe@lists.freedesktop.org Cc: Rodrigo Vivi , Manasi Navare , Drew Davenport , Sean Paul , Samuel Jacob , Rajat Jain , Juasheem Sultan Subject: Re: [RFC PATCH v3 2/2] drm/i915/display: Synchronize crtc_state for initial commit In-Reply-To: <20260121204705.432290-3-jdsultan@google.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland References: <20260121204705.432290-1-jdsultan@google.com> <20260121204705.432290-3-jdsultan@google.com> Date: Thu, 22 Jan 2026 17:29:46 +0200 Message-ID: <19ddb0a9aa900c51759cfa62b66bcbf079c4dde8@intel.com> MIME-Version: 1.0 Content-Type: text/plain 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Wed, 21 Jan 2026, Juasheem Sultan wrote: > When attempting the initial commit, there is a mismatch between > the new crtc_state and the old crtc_state. This causes us to fail the > pipe_config comparison and force a modeset. In the case where we are > inheriting an initialized state, we can sync the new and the old state > to pass the comparison and allow us to do a fastset and achieve an > uninterrupted handoff to userspace. > > Signed-off-by: Juasheem Sultan > --- > drivers/gpu/drm/i915/display/intel_display.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index 0d527cf22866..6eef4bd2e251 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -5736,6 +5736,25 @@ static void intel_crtc_check_fastset(const struct intel_crtc_state *old_crtc_sta > if (old_crtc_state->vrr.in_range != new_crtc_state->vrr.in_range) > new_crtc_state->update_lrr = false; > > + /* Copying crtc state if inheriting an old state for commit */ > + if (old_crtc_state->inherited) { > + new_crtc_state->hw = old_crtc_state->hw; > + > + new_crtc_state->port_clock = old_crtc_state->port_clock; > + new_crtc_state->pipe_bpp = old_crtc_state->pipe_bpp; > + new_crtc_state->cpu_transcoder = old_crtc_state->cpu_transcoder; > + new_crtc_state->lane_count = old_crtc_state->lane_count; > + new_crtc_state->output_types = old_crtc_state->output_types; > + new_crtc_state->dp_m_n = old_crtc_state->dp_m_n; > + new_crtc_state->framestart_delay = old_crtc_state->framestart_delay; > + new_crtc_state->pixel_multiplier = old_crtc_state->pixel_multiplier; > + new_crtc_state->pixel_rate = old_crtc_state->pixel_rate; > + new_crtc_state->enhanced_framing = old_crtc_state->enhanced_framing; > + new_crtc_state->dpll_hw_state = old_crtc_state->dpll_hw_state; > + new_crtc_state->intel_dpll = old_crtc_state->intel_dpll; > + new_crtc_state->vrr.guardband = old_crtc_state->vrr.guardband; I'd like to see logs of what the differences are. BR, Jani. > + } > + > if (!intel_pipe_config_compare(old_crtc_state, new_crtc_state, true)) { > drm_dbg_kms(display->drm, "[CRTC:%d:%s] fastset requirement not met, forcing full modeset\n", > crtc->base.base.id, crtc->base.name); -- Jani Nikula, Intel