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 BC87DC5AC7A for ; Fri, 7 Aug 2026 04:32:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3001310F384; Fri, 7 Aug 2026 04:32:13 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="IL3aQwxo"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9092010F37A; Fri, 7 Aug 2026 04:32:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1786077130; x=1817613130; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=pWRELeUPzDls68T8C5CG7z6YNQLtrvJKMe0JjSjempE=; b=IL3aQwxoblA+adBmHc4KHVbzjsXPAC68Z4orDZxtwnpwMvqSNkBvLa5s r6QTITF8vD+0mbrw/p8q3L0BX3lS4ZqT3Ij45bYjBytyctzOtS7y2F24m JTt6krtzJ7NsiF8B+/eDl1d0gBMOCl3ji0N+LBxx1or9C0GfVbN0GXTLZ glSHbI/s9OKgLSzM8501xcTcIRYH7IdAMWvBbqSypWUAdnSsoDpC3P2k4 VTntCoogJIH82QGgERKT0lPXt94vpzjnQThO8tqKAgJLZLxSRpElJh+eG CnF32rkq/3yn6bb4jG3Ey52ZFkaG8jM58vT2DYB3O1g0cMmOBCQAlQM2N Q==; X-CSE-ConnectionGUID: 6VAjaJH7RBurSjSdfBCgAQ== X-CSE-MsgGUID: h1VCcO0PQ9qy5hjeDydkng== X-IronPort-AV: E=McAfee;i="6800,10657,11867"; a="86619273" X-IronPort-AV: E=Sophos;i="6.25,209,1779174000"; d="scan'208";a="86619273" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2026 21:32:09 -0700 X-CSE-ConnectionGUID: u1NQCuIFR/iOfF0xb8uHrw== X-CSE-MsgGUID: 6MDLKRqiTxunCF88Q4g/OA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,209,1779174000"; d="scan'208";a="285666185" Received: from srr4-3-linux-103-aknautiy.iind.intel.com ([10.223.34.160]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2026 21:32:07 -0700 From: Ankit Nautiyal To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org, jani.nikula@linux.intel.com, uma.shankar@intel.com, ville.syrjala@linux.intel.com, suraj.kandpal@intel.com Subject: [PATCH 16/44] drm/i915/hdmi: Reduce FRL rate cap on rate change during training Date: Fri, 7 Aug 2026 09:44:01 +0530 Message-ID: <20260807041430.229038-17-ankit.k.nautiyal@intel.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260807041430.229038-1-ankit.k.nautiyal@intel.com> References: <20260807041430.229038-1-ankit.k.nautiyal@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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" If the sink requests a rate change during FRL Link training, reduce frl.rate_cap to the next lower FRL rate. The next mode compute then uses this lower rate cap, so we do not attempt the failing rate again. Signed-off-by: Ankit Nautiyal --- drivers/gpu/drm/i915/display/intel_hdmi.c | 27 ++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c index fe4923c82463..2b0cdb0719e2 100644 --- a/drivers/gpu/drm/i915/display/intel_hdmi.c +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c @@ -3720,6 +3720,18 @@ intel_hdmi_frl_train_lts3(struct intel_encoder *encoder, return frl_train_complete_ltsp(encoder, crtc_state); } +static int get_next_frl_rate(int curr_rate_gbps) +{ + int valid_rate[] = { 48, 40, 32, 24, 18, 9 }; + int i; + + for (i = 0; i < ARRAY_SIZE(valid_rate); i++) + if (valid_rate[i] < curr_rate_gbps) + return valid_rate[i]; + + return -EINVAL; +} + static int get_ffe_level(int rate_gbps) { return 0; @@ -3736,6 +3748,7 @@ int intel_hdmi_start_frl(struct intel_encoder *encoder, int req_rate = crtc_state->frl.required_lanes * crtc_state->frl.required_rate; int ffe_level = get_ffe_level(req_rate); enum frl_lt_status status; + int next_rate = -EINVAL; if (!crtc_state->frl.enable) return 0; @@ -3769,10 +3782,22 @@ int intel_hdmi_start_frl(struct intel_encoder *encoder, connector->base.id, connector->name, intel_hdmi->frl.rate_gbps); return 0; - default: + case FRL_TRAIN_STOP: + next_rate = 0; + break; + case FRL_CHANGE_RATE: + next_rate = get_next_frl_rate(req_rate); break; + case FRL_TRAIN_RETRAIN: + fallthrough; + default: + goto ltsl_tmds_mode; } + if (next_rate >= 0) + intel_hdmi->frl.rate_cap = next_rate; + +ltsl_tmds_mode: if (crtc_state->frl.enable && !intel_hdmi->frl.trained) drm_err(display->drm, "[CONNECTOR:%d:%s] FRL Training Failed with rate=%d\n", -- 2.50.1