From patchwork Tue Sep 27 16:59:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= X-Patchwork-Id: 12990985 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 22728C54EE9 for ; Tue, 27 Sep 2022 17:00:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 084C110E0A0; Tue, 27 Sep 2022 17:00:33 +0000 (UTC) Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 483FA10E05C; Tue, 27 Sep 2022 17:00:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1664298014; x=1695834014; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FhJMM87k0x5zG3sXLdlJ9nnD79G+3grLJBKMOo94wRA=; b=YrsNFxSlQvllGgp2ogys7VIhyX+pcfyZammA4zDPaKcFKkN2vYZColHk Ghnf0TED9dhx+X3RAWNYH63zSZc6v0tjb0WyWiT/bSjYa4M7+8Xt1zzwb LY6wj3u2QW5RNtfrFhv9d7kgI6DmBYH9vZZmpMMNd5VrkgdMfUUjvFHoK BGDHT3JfCjmYVI8Bf8FloFjJGk5NV3uf9lncsxOBYXjg4F+KAQIy9IFZq kjHV9cunAQJKWr/YtJc7IvZnw8XhSYKp+KfNEPKHHEEiNxjzZqDmtuP9k C2xTu3x0+9kW0c47Wng1byhPHiIhtUwkNq4K0DVXmvHbXFw9b7+5vX2vm Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10483"; a="363208133" X-IronPort-AV: E=Sophos;i="5.93,349,1654585200"; d="scan'208";a="363208133" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Sep 2022 10:00:13 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10483"; a="623821484" X-IronPort-AV: E=Sophos;i="5.93,349,1654585200"; d="scan'208";a="623821484" Received: from stinkpipe.fi.intel.com (HELO stinkbox) ([10.237.72.191]) by fmsmga007.fm.intel.com with SMTP; 27 Sep 2022 10:00:10 -0700 Received: by stinkbox (sSMTP sendmail emulation); Tue, 27 Sep 2022 20:00:09 +0300 From: Ville Syrjala To: dri-devel@lists.freedesktop.org Subject: [PATCH v2 1/9] drm/edid: Clarify why we only accept the "range limits only" descriptor Date: Tue, 27 Sep 2022 19:59:58 +0300 Message-Id: <20220927170006.27855-2-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220927170006.27855-1-ville.syrjala@linux.intel.com> References: <20220927170006.27855-1-ville.syrjala@linux.intel.com> 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: Leo Li , intel-gfx@lists.freedesktop.org, Rodrigo Siqueira , amd-gfx@lists.freedesktop.org, Manasi Navare , Nicholas Kazlauskas Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Ville Syrjälä The current comment fails to clarify why we only accept the "range limits only" variant of the range descriptor. Reword it to make some actual sense. Cc: Nicholas Kazlauskas Cc: Harry Wentland Cc: Leo Li Cc: Rodrigo Siqueira Cc: amd-gfx@lists.freedesktop.org Reviewed-by: Manasi Navare Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/drm_edid.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 4005dab6147d..ac662495635c 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -6033,10 +6033,13 @@ void get_monitor_range(const struct detailed_timing *timing, void *c) return; /* - * Check for flag range limits only. If flag == 1 then - * no additional timing information provided. - * Default GTF, GTF Secondary curve and CVT are not - * supported + * These limits are used to determine the VRR refresh + * rate range. Only the "range limits only" variant + * of the range descriptor seems to guarantee that + * any and all timings are accepted by the sink, as + * opposed to just timings conforming to the indicated + * formula (GTF/GTF2/CVT). Thus other variants of the + * range descriptor are not accepted here. */ if (range->flags != DRM_EDID_RANGE_LIMITS_ONLY_FLAG) return;