From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 851903FAE19; Tue, 25 Aug 2026 13:48:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787665698; cv=none; b=Eu7QMcL+9sWv86dkOpbRY5nYJemUju5lvSQTKxmNfml6k8ZTgq+kYiDk7XuVKmNUa6cz7OfR+5iqOyGwHpVjRNsy7tCf8WyJflE2lgUZ/UXz7r9wmM2tZQSUsiy+D42BofrYsfxAkdQi6AeqNIVL9R0RjPA78nIcwgG/8l+1ac0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787665698; c=relaxed/simple; bh=YynlBfIOI218aR/XpgGKu5tcODV4b+aVRU6tus0FHUo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=h4nMTXvDOFMNQ4nk87r7kWM9sz1oEEwAPMNM12amWM9/MGVOt5yk7+tTw1f/xWVP7Yk8S30VUAkvAJn0eQcZwedW8a2szxcwyPtoUU4J5GRi9FVfBSRlXj5VZAR28Ar+ta3sgMtNDtdkhVRLzg/vAXxHVsFEYPmnfqilCPzvrCM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YexIXNmd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="YexIXNmd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C39F1F00A3A; Tue, 25 Aug 2026 13:48:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787665697; bh=irisC69SCi8NqOSV/vcunHaG5MI0tOFrRKaUcI8orVc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=YexIXNmd1JP2pvQCRdEeY0GE4jmLgAwTw0ShqdtW5Hn4jssw8Mj7amOpEGDQQjnA/ cH0jkEAAxj+PGEEOxsSdJCYH//pw9oul4R4gD9MCYUOTnpcXIbl+cpqp5HYLK70yUG jXJFgJgVvOqphkv8turk5HlcTgbayKuLLExvy6WI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Igor Paunovic , Satyajit Roy , Nathan Lucas , Alex Deucher , Sasha Levin Subject: [PATCH 6.6 36/87] drm/amd/display: fix BT.2020 YCbCr limited output CSC matrix Date: Tue, 25 Aug 2026 15:25:59 +0200 Message-ID: <20260825132543.266710703@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260825132541.813800447@linuxfoundation.org> References: <20260825132541.813800447@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nathan Lucas [ Upstream commit 2f9a5c0f018d4a1586ee892f81f1383219676415 ] COLOR_SPACE_YCBCR2020_TYPE, which is selected for COLOR_SPACE_2020_YCBCR_LIMITED color_space, has coefficients that are incorrect for limited-range output. Its luma and chroma scaling is full-range so output is too bright and colors are incorrect. COLOR_SPACE_YCBCR2020_TYPE is closer to a full-range conversion matrix with incorrect luma offset, so correct the luma offset for full-range and rename it to COLOR_SPACE_YCBCR2020_FULL_TYPE. Add COLOR_SPACE_YCBCR2020_LIMITED_TYPE with correct scaling and range for limited-range output. Fix related functions so COLOR_SPACE_YCBCR2020_LIMITED_TYPE and COLOR_SPACE_YCBCR2020_FULL_TYPE are correctly selected based on dc_color_space. Derivation of both matrices follows ITU-T H.273: Table 4, MatrixCoefficients 9, BT.2020-NCL weights: KR = 0.2627, KB = 0.0593, KG = 1 - KR - KB = 0.6780. Equations 45-47 in matrix form: [ KR KG KB 0 ] M2020_NCL = [ -KR/(2(1-KB)) -KG/(2(1-KB)) 1/2 0 ] [ 1/2 -KG/(2(1-KR)) -KB/(2(1-KR)) 0 ] [ 0 0 0 1 ] Limited and Full transforms based on equations 30-32 and 36-38 with bit depth 10, normalized by 1023: [ 876/1023 0 0 64/1023 ] MLimited = [ 0 896/1023 0 512/1023 ] [ 0 0 896/1023 512/1023 ] [ 0 0 0 1 ] [ 1023/1023 0 0 0 ] MFull = [ 0 1023/1023 0 512/1023 ] [ 0 0 1023/1023 512/1023 ] [ 0 0 0 1 ] M2020_NCL_Limited = MLimited x M2020_NCL M2020_NCL_Full = MFull x M2020_NCL The upper three rows of M2020_NCL_* are stored in CR, Y, CB order. Each M2020_NCL_* value is stored as Round(value * 8192) in its 16-bit two's-complement representation. Fixes: 973a9c810c78 ("drm/amd/display: Fix COLOR_SPACE_YCBCR2020_TYPE matrix") Assisted-by: OpenAI-Codex:GPT-5.6-Sol Tested-by: Igor Paunovic Tested-by: Satyajit Roy Signed-off-by: Nathan Lucas Signed-off-by: Alex Deucher (cherry picked from commit 3b906e1dc7e3c9ff9f7940f6828b367a6a9ec73c) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c | 31 +++++++++++------- 1 file changed, 20 insertions(+), 11 deletions(-) --- a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c @@ -47,7 +47,8 @@ enum dc_color_space_type { COLOR_SPACE_RGB_LIMITED_TYPE, COLOR_SPACE_YCBCR601_TYPE, COLOR_SPACE_YCBCR709_TYPE, - COLOR_SPACE_YCBCR2020_TYPE, + COLOR_SPACE_YCBCR2020_LIMITED_TYPE, + COLOR_SPACE_YCBCR2020_FULL_TYPE, COLOR_SPACE_YCBCR601_LIMITED_TYPE, COLOR_SPACE_YCBCR709_LIMITED_TYPE, COLOR_SPACE_YCBCR709_BLACK_TYPE, @@ -99,9 +100,15 @@ static const struct out_csc_color_matrix { 0xE00, 0xF349, 0xFEB7, 0x1000, 0x6CE, 0x16E3, 0x24F, 0x200, 0xFCCB, 0xF535, 0xE00, 0x1000} }, - { COLOR_SPACE_YCBCR2020_TYPE, + /* Corrected. Not included in the TODO above. */ + { COLOR_SPACE_YCBCR2020_LIMITED_TYPE, + { 0x0E04, 0xF31D, 0xFEDF, 0x1004, + 0x0733, 0x1294, 0x01A0, 0x0201, + 0xFC16, 0xF5E6, 0x0E04, 0x1004} }, + /* Corrected. Not included in the TODO above. */ + { COLOR_SPACE_YCBCR2020_FULL_TYPE, { 0x1000, 0xF149, 0xFEB7, 0x1004, - 0x0868, 0x15B2, 0x01E6, 0x201, + 0x0868, 0x15B2, 0x01E6, 0, 0xFB88, 0xF478, 0x1000, 0x1004} }, { COLOR_SPACE_YCBCR709_BLACK_TYPE, { 0x0000, 0x0000, 0x0000, 0x1000, @@ -168,14 +175,14 @@ static bool is_ycbcr709_type( return ret; } -static bool is_ycbcr2020_type( - enum dc_color_space color_space) +static bool is_ycbcr2020_limited_type(enum dc_color_space color_space) { - bool ret = false; + return color_space == COLOR_SPACE_2020_YCBCR_LIMITED; +} - if (color_space == COLOR_SPACE_2020_YCBCR_LIMITED || color_space == COLOR_SPACE_2020_YCBCR_FULL) - ret = true; - return ret; +static bool is_ycbcr2020_full_type(enum dc_color_space color_space) +{ + return color_space == COLOR_SPACE_2020_YCBCR_FULL; } static bool is_ycbcr709_limited_type( @@ -204,8 +211,10 @@ static enum dc_color_space_type get_colo type = COLOR_SPACE_YCBCR601_LIMITED_TYPE; else if (is_ycbcr709_limited_type(color_space)) type = COLOR_SPACE_YCBCR709_LIMITED_TYPE; - else if (is_ycbcr2020_type(color_space)) - type = COLOR_SPACE_YCBCR2020_TYPE; + else if (is_ycbcr2020_limited_type(color_space)) + type = COLOR_SPACE_YCBCR2020_LIMITED_TYPE; + else if (is_ycbcr2020_full_type(color_space)) + type = COLOR_SPACE_YCBCR2020_FULL_TYPE; else if (color_space == COLOR_SPACE_YCBCR709) type = COLOR_SPACE_YCBCR709_BLACK_TYPE; else if (color_space == COLOR_SPACE_YCBCR709_BLACK)