From patchwork Thu Apr 23 15:17:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Ville Syrjala X-Patchwork-Id: 11505873 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6440914DD for ; Thu, 23 Apr 2020 15:17:50 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 4C4FC206EC for ; Thu, 23 Apr 2020 15:17:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4C4FC206EC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id ED5ED6E88D; Thu, 23 Apr 2020 15:17:48 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTPS id 762D16E88D; Thu, 23 Apr 2020 15:17:47 +0000 (UTC) IronPort-SDR: VSj4dTBGTJgXuWLNk9s3dSS0ep65B12GNw/gXi4ajA8Fld/WSjH2suI1x5suqyV/aS983zubX2 0S+F0+TVdtlg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Apr 2020 08:17:47 -0700 IronPort-SDR: fy7yKvh7T2zNzZNCVaQq2XQHqN9fxWosy5gium/Inm9vptlj2UhOGg1ng+p0Ifj2mcXyt5m0T8 0kPhmGDSrXXg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,307,1583222400"; d="scan'208";a="244896817" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by orsmga007.jf.intel.com with SMTP; 23 Apr 2020 08:17:44 -0700 Received: by stinkbox (sSMTP sendmail emulation); Thu, 23 Apr 2020 18:17:43 +0300 From: Ville Syrjala To: dri-devel@lists.freedesktop.org Subject: [PATCH] drm/edid: Fix off-by-one in DispID DTD pixel clock Date: Thu, 23 Apr 2020 18:17:43 +0300 Message-Id: <20200423151743.18767-1-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org, stable@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Ville Syrjälä The DispID DTD pixel clock is documented as: "00 00 00 h → FF FF FF h | Pixel clock ÷ 10,000 0.01 → 167,772.16 Mega Pixels per Sec" Which seems to imply that we to add one to the raw value. Reality seems to agree as there are tiled displays in the wild which currently show a 10kHz difference in the pixel clock between the tiles (one tile gets its mode from the base EDID, the other from the DispID block). Cc: stable@vger.kernel.org References: https://gitlab.freedesktop.org/drm/intel/-/issues/27 Signed-off-by: Ville Syrjälä Reviewed-by: Manasi Navare --- drivers/gpu/drm/drm_edid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 43b6ca364daa..544d2603f5fc 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -5120,7 +5120,7 @@ static struct drm_display_mode *drm_mode_displayid_detailed(struct drm_device *d struct drm_display_mode *mode; unsigned pixel_clock = (timings->pixel_clock[0] | (timings->pixel_clock[1] << 8) | - (timings->pixel_clock[2] << 16)); + (timings->pixel_clock[2] << 16)) + 1; unsigned hactive = (timings->hactive[0] | timings->hactive[1] << 8) + 1; unsigned hblank = (timings->hblank[0] | timings->hblank[1] << 8) + 1; unsigned hsync = (timings->hsync[0] | (timings->hsync[1] & 0x7f) << 8) + 1;