From patchwork Wed Sep 25 03:44:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Murthy, Arun R" X-Patchwork-Id: 13811586 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 31543CF9C74 for ; Wed, 25 Sep 2024 03:54:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D1F3B10E781; Wed, 25 Sep 2024 03:54:23 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="IdDhHTsj"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4DB2110E8F2; Wed, 25 Sep 2024 03:54:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1727236459; x=1758772459; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tMKMfAEk7st0mQ7orHkYHUZ2g+yC6RJiwIM/FTiodcE=; b=IdDhHTsjNm6eQ/ogoz2i4Du8b2BCty7Gg5DxB6Axgq54Ue6m0juuv0sc uKxNDWtThfOcwINxSI/dn2zf11BsmXUjrA0As8cwT/Xq56icr5y/eYcm9 gU76AcEZpm9yVoSdYkv/71Tx0PtoNzyQV5MnQDTh1eKbviSr0Qj6lwfJe Mr4jdacipQ0+0Oq9owmmKwDJpsrRbDRer0uF5RxlDnCHxWkMbgjyNoZ3L SCc3YigVPIWlAUB/mXDSaSd59K+FFfVfm7G8mJYyuU+YEMu0f//gu87ql WmNPFHNHMJ2OGbuJu/K+2xmFOpO+wu2z/pcnneV8MdgaefWW7vgR/P+3l A==; X-CSE-ConnectionGUID: CVvtEdsWTD2ePfZeSP/AAw== X-CSE-MsgGUID: Xk1HrHhyQRi7KHyXhEe/1A== X-IronPort-AV: E=McAfee;i="6700,10204,11205"; a="37640817" X-IronPort-AV: E=Sophos;i="6.10,256,1719903600"; d="scan'208";a="37640817" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Sep 2024 20:54:19 -0700 X-CSE-ConnectionGUID: evgcM7GiQBW7EH0B94QD0g== X-CSE-MsgGUID: 2PpTDy+hSu+IMzJJnY8z4Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,256,1719903600"; d="scan'208";a="71781162" Received: from srr4-3-linux-106-armuthy.iind.intel.com ([10.190.238.56]) by fmviesa008.fm.intel.com with ESMTP; 24 Sep 2024 20:54:18 -0700 From: Arun R Murthy To: intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: Arun R Murthy , Srikanth V NagaVenkata , Suraj Kandpal Subject: [PATCHv3 2/3] drm/i915/dp: read Aux RD interval just before setting the FFE preset Date: Wed, 25 Sep 2024 09:14:31 +0530 Message-Id: <20240925034432.1777029-3-arun.r.murthy@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240925034432.1777029-1-arun.r.murthy@intel.com> References: <20240925034432.1777029-1-arun.r.murthy@intel.com> MIME-Version: 1.0 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" Figure 3-52: 128b132b DP DPTC LANEx_CHANNEL_EQ_DONE Sequence of DP2.1a spec. After reading LANEx_CHANNEL_EQ_DONE, read the FFE presets. AUX_RD_INTERVAL and then write the new FFE presets. Co-developed-by: Srikanth V NagaVenkata Signed-off-by: Arun R Murthy Reviewed-by: Suraj Kandpal --- .../gpu/drm/i915/display/intel_dp_link_training.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c index f41b69840ad9..1bac00e46533 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -1419,12 +1419,6 @@ intel_dp_128b132b_lane_eq(struct intel_dp *intel_dp, for (try = 0; try < max_tries; try++) { fsleep(delay_us); - /* - * The delay may get updated. The transmitter shall read the - * delay before link status during link training. - */ - delay_us = drm_dp_128b132b_read_aux_rd_interval(&intel_dp->aux); - if (drm_dp_dpcd_read_link_status(&intel_dp->aux, link_status) < 0) { lt_err(intel_dp, DP_PHY_DPRX, "Failed to read link status\n"); return false; @@ -1451,8 +1445,14 @@ intel_dp_128b132b_lane_eq(struct intel_dp *intel_dp, if (time_after(jiffies, deadline)) timeout = true; /* try one last time after deadline */ - /* Update signal levels and training set as requested. */ intel_dp_get_adjust_train(intel_dp, crtc_state, DP_PHY_DPRX, link_status); + /* + * During LT, Tx shall read AUX_RD_INTERVAL just before writing the new FFE + * presets. + */ + delay_us = drm_dp_128b132b_read_aux_rd_interval(&intel_dp->aux); + + /* Update signal levels and training set as requested. */ if (!intel_dp_update_link_train(intel_dp, crtc_state, DP_PHY_DPRX)) { lt_err(intel_dp, DP_PHY_DPRX, "Failed to update TX FFE settings\n"); return false;