From nobody Mon Feb 9 17:23:59 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 93BCA13EFF4; Tue, 26 Mar 2024 15:41:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711467673; cv=none; b=IU0xLcCNkHQSEzX3UgPiqcTRYxaMLoyRlCmJsqptzvXvBOcfNlVBSvj6WxwbuWF2xIfxnPqxzgUEdu04gVYGLRMljDy20gARtHqGIXyJox+BpsdXrOXEdRCgv/q2krfZi2KBxzYZvo7M3gwirhT8N5LO8RtjroB5wr6KLTbOjdU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711467673; c=relaxed/simple; bh=HpUrolYR+ACe5u1nRopOeqbxhk4RPWm36DemTlIjZG8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ZwzfSlk+T+vXOU+xMaZtVLPELHA7GIc4z4QdfYDewWA2LxYDkiNwnwOADthjFWFKc50YK/5ZVm8cmPRVzF6K4Y5sIsQ3H3Hhg4zk6s2Qr4JidlAXJa9CzwzCUK1bT3Wk0iN6H5UiqUECyLlqEe+v3mSHNgsf5CyZpWhAS4MUBwQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aeh96zqX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aeh96zqX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24A77C433F1; Tue, 26 Mar 2024 15:41:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711467673; bh=HpUrolYR+ACe5u1nRopOeqbxhk4RPWm36DemTlIjZG8=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=aeh96zqX1NDkbfMRTHBQSEuR2u6bhaECadVLXnXrp1hlf8LGy2pne/Xc/v9IY76gC hMZOUwQu7k7tz4ASqPb4PV0J9R7uzuwHIMD4bKtjBH51DVw6+ZHKfrkGogNZMD4XcW X0q2nYynVwpRkht5C9RMD+F1ce9EU/tPttiIOpwrKWTxPSfodUqRzqF30qUmnbmg8A B4A3HABQCcLcNU6eII9bxq+o4uXn17+cUaAEO9B8ww8kjW4GFQvOVRgILtJAW+b6oa kk9iMqoTm7jABly/DYvnHQYNM6G/Eac0fFC1C4zkGQhYhH+qJ+5EcITwyROIKq0E4n XlJ2VtAQDXL6A== From: Maxime Ripard Date: Tue, 26 Mar 2024 16:40:19 +0100 Subject: [PATCH v11 15/28] drm/connector: hdmi: Compute bpc and format automatically Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20240326-kms-hdmi-connector-state-v11-15-c5680ffcf261@kernel.org> References: <20240326-kms-hdmi-connector-state-v11-0-c5680ffcf261@kernel.org> In-Reply-To: <20240326-kms-hdmi-connector-state-v11-0-c5680ffcf261@kernel.org> To: Maarten Lankhorst , Thomas Zimmermann , David Airlie , Daniel Vetter , Jonathan Corbet , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland Cc: Hans Verkuil , Sebastian Wick , =?utf-8?q?Ville_Syrj=C3=A4l=C3=A4?= , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-sunxi@lists.linux.dev, Maxime Ripard X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=11722; i=mripard@kernel.org; h=from:subject:message-id; bh=HpUrolYR+ACe5u1nRopOeqbxhk4RPWm36DemTlIjZG8=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDGlMb1IvzrhXPv904oR0m46mI+6P/kx/9bZe2bJOTTdub m1/+SSWjqksDMKcDLJiiixPZMJOL29fXOVgv/IHzBxWJpAhDFycAjAR/emM9Q6n2RgevF8q3xl/ a17qultP7b/M9Jl6LmbGyj7BCn7td8ZPThftsU5xE59ms9Zry4SpEYwNF9cKhLoyuKune2UXvU6 STJq2dqpU+n/OnZfKj/4ob1zraDQ/uUs8VqJBLdVK9fG7BgYA X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D Now that we have all the infrastructure needed, we can add some code that will, for a given connector state and mode, compute the best output format and bpc. The algorithm is equivalent to the one already found in i915 and vc4. Signed-off-by: Maxime Ripard --- drivers/gpu/drm/display/drm_hdmi_state_helper.c | 197 +++++++++++++++++= +++- drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 25 ++- 2 files changed, 210 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/= drm/display/drm_hdmi_state_helper.c index 063421835dba..b9bc0fb027ea 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -1,9 +1,11 @@ // SPDX-License-Identifier: MIT =20 #include #include +#include +#include =20 #include #include =20 /** @@ -46,10 +48,110 @@ connector_state_get_mode(const struct drm_connector_st= ate *conn_state) return NULL; =20 return &crtc_state->mode; } =20 +static bool +sink_supports_format_bpc(const struct drm_connector *connector, + const struct drm_display_info *info, + const struct drm_display_mode *mode, + unsigned int format, unsigned int bpc) +{ + struct drm_device *dev =3D connector->dev; + u8 vic =3D drm_match_cea_mode(mode); + + /* + * CTA-861-F, section 5.4 - Color Coding & Quantization states + * that the bpc must be 8, 10, 12 or 16 except for the default + * 640x480 VIC1 where the value must be 8. + * + * The definition of default here is ambiguous but the spec + * refers to VIC1 being the default timing in several occasions + * so our understanding is that for the default timing (ie, + * VIC1), the bpc must be 8. + */ + if (vic =3D=3D 1 && bpc !=3D 8) { + drm_dbg_kms(dev, "VIC1 requires a bpc of 8, got %u\n", bpc); + return false; + } + + if (!info->is_hdmi && + (format !=3D HDMI_COLORSPACE_RGB || bpc !=3D 8)) { + drm_dbg_kms(dev, "DVI Monitors require an RGB output at 8 bpc\n"); + return false; + } + + if (!(connector->hdmi.supported_formats & BIT(format))) { + drm_dbg_kms(dev, "%s format unsupported by the connector.\n", + drm_hdmi_connector_get_output_format_name(format)); + return false; + } + + switch (format) { + case HDMI_COLORSPACE_RGB: + drm_dbg_kms(dev, "RGB Format, checking the constraints.\n"); + + if (!(info->color_formats & DRM_COLOR_FORMAT_RGB444)) + return false; + + if (bpc =3D=3D 10 && !(info->edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_D= C_30)) { + drm_dbg_kms(dev, "10 BPC but sink doesn't support Deep Color 30.\n"); + return false; + } + + if (bpc =3D=3D 12 && !(info->edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_D= C_36)) { + drm_dbg_kms(dev, "12 BPC but sink doesn't support Deep Color 36.\n"); + return false; + } + + drm_dbg_kms(dev, "RGB format supported in that configuration.\n"); + + return true; + + case HDMI_COLORSPACE_YUV422: + drm_dbg_kms(dev, "YUV422 format, checking the constraints.\n"); + + if (!(info->color_formats & DRM_COLOR_FORMAT_YCBCR422)) { + drm_dbg_kms(dev, "Sink doesn't support YUV422.\n"); + return false; + } + + if (bpc !=3D 12) { + drm_dbg_kms(dev, "YUV422 only supports 12 bpc.\n"); + return false; + } + + drm_dbg_kms(dev, "YUV422 format supported in that configuration.\n"); + + return true; + + case HDMI_COLORSPACE_YUV444: + drm_dbg_kms(dev, "YUV444 format, checking the constraints.\n"); + + if (!(info->color_formats & DRM_COLOR_FORMAT_YCBCR444)) { + drm_dbg_kms(dev, "Sink doesn't support YUV444.\n"); + return false; + } + + if (bpc =3D=3D 10 && !(info->edid_hdmi_ycbcr444_dc_modes & DRM_EDID_HDMI= _DC_30)) { + drm_dbg_kms(dev, "10 BPC but sink doesn't support Deep Color 30.\n"); + return false; + } + + if (bpc =3D=3D 12 && !(info->edid_hdmi_ycbcr444_dc_modes & DRM_EDID_HDMI= _DC_36)) { + drm_dbg_kms(dev, "12 BPC but sink doesn't support Deep Color 36.\n"); + return false; + } + + drm_dbg_kms(dev, "YUV444 format supported in that configuration.\n"); + + return true; + } + + return false; +} + static enum drm_mode_status hdmi_clock_valid(const struct drm_connector *connector, const struct drm_display_mode *mode, unsigned long long clock) { @@ -90,10 +192,101 @@ hdmi_compute_clock(const struct drm_connector *connec= tor, conn_state->hdmi.tmds_char_rate =3D clock; =20 return 0; } =20 +static bool +hdmi_try_format_bpc(const struct drm_connector *connector, + struct drm_connector_state *conn_state, + const struct drm_display_mode *mode, + unsigned int bpc, enum hdmi_colorspace fmt) +{ + const struct drm_display_info *info =3D &connector->display_info; + struct drm_device *dev =3D connector->dev; + int ret; + + drm_dbg_kms(dev, "Trying %s output format\n", + drm_hdmi_connector_get_output_format_name(fmt)); + + if (!sink_supports_format_bpc(connector, info, mode, fmt, bpc)) { + drm_dbg_kms(dev, "%s output format not supported with %u bpc\n", + drm_hdmi_connector_get_output_format_name(fmt), + bpc); + return false; + } + + ret =3D hdmi_compute_clock(connector, conn_state, mode, bpc, fmt); + if (ret) { + drm_dbg_kms(dev, "Couldn't compute clock for %s output format and %u bpc= \n", + drm_hdmi_connector_get_output_format_name(fmt), + bpc); + return false; + } + + drm_dbg_kms(dev, "%s output format supported with %u (TMDS char rate: %ll= u Hz)\n", + drm_hdmi_connector_get_output_format_name(fmt), + bpc, conn_state->hdmi.tmds_char_rate); + + return true; +} + +static int +hdmi_compute_format(const struct drm_connector *connector, + struct drm_connector_state *conn_state, + const struct drm_display_mode *mode, + unsigned int bpc) +{ + struct drm_device *dev =3D connector->dev; + + /* + * TODO: Add support for YCbCr420 output for HDMI 2.0 capable + * devices, for modes that only support YCbCr420. + */ + if (hdmi_try_format_bpc(connector, conn_state, mode, bpc, HDMI_COLORSPACE= _RGB)) { + conn_state->hdmi.output_format =3D HDMI_COLORSPACE_RGB; + return 0; + } + + drm_dbg_kms(dev, "Failed. No Format Supported for that bpc count.\n"); + + return -EINVAL; +} + +static int +hdmi_compute_config(const struct drm_connector *connector, + struct drm_connector_state *conn_state, + const struct drm_display_mode *mode) +{ + struct drm_device *dev =3D connector->dev; + unsigned int max_bpc =3D clamp_t(unsigned int, + conn_state->max_bpc, + 8, connector->max_bpc); + unsigned int bpc; + int ret; + + for (bpc =3D max_bpc; bpc >=3D 8; bpc -=3D 2) { + drm_dbg_kms(dev, "Trying with a %d bpc output\n", bpc); + + ret =3D hdmi_compute_format(connector, conn_state, mode, bpc); + if (ret) + continue; + + conn_state->hdmi.output_bpc =3D bpc; + + drm_dbg_kms(dev, + "Mode %ux%u @ %uHz: Found configuration: bpc: %u, fmt: %s, clock: %= llu\n", + mode->hdisplay, mode->vdisplay, drm_mode_vrefresh(mode), + conn_state->hdmi.output_bpc, + drm_hdmi_connector_get_output_format_name(conn_state->hdmi.output_f= ormat), + conn_state->hdmi.tmds_char_rate); + + return 0; + } + + return -EINVAL; +} + /** * drm_atomic_helper_connector_hdmi_check() - Helper to check HDMI connect= or atomic state * @connector: DRM Connector * @state: the DRM State object * @@ -113,13 +306,11 @@ int drm_atomic_helper_connector_hdmi_check(struct drm= _connector *connector, drm_atomic_get_new_connector_state(state, connector); const struct drm_display_mode *mode =3D connector_state_get_mode(new_conn_state); int ret; =20 - ret =3D hdmi_compute_clock(connector, new_conn_state, mode, - new_conn_state->hdmi.output_bpc, - new_conn_state->hdmi.output_format); + ret =3D hdmi_compute_config(connector, new_conn_state, mode); if (ret) return ret; =20 if (old_conn_state->hdmi.output_bpc !=3D new_conn_state->hdmi.output_bpc = || old_conn_state->hdmi.output_format !=3D new_conn_state->hdmi.output_f= ormat) { diff --git a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c b/drivers/g= pu/drm/tests/drm_hdmi_state_helper_test.c index ead998a691e7..a49a544d7b49 100644 --- a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +++ b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c @@ -70,13 +70,10 @@ static int light_up_connector(struct kunit *test, KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state); =20 conn_state =3D drm_atomic_get_connector_state(state, connector); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, conn_state); =20 - conn_state->hdmi.output_bpc =3D connector->max_bpc; - conn_state->hdmi.output_format =3D HDMI_COLORSPACE_RGB; - ret =3D drm_atomic_set_crtc_for_connector(conn_state, crtc); KUNIT_EXPECT_EQ(test, ret, 0); =20 crtc_state =3D drm_atomic_get_crtc_state(state, crtc); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state); @@ -251,14 +248,19 @@ static void drm_test_check_output_bpc_crtc_mode_chang= ed(struct kunit *test) priv =3D drm_atomic_helper_connector_hdmi_init(test, BIT(HDMI_COLORSPACE_RGB), 10); KUNIT_ASSERT_NOT_NULL(test, priv); =20 + conn =3D &priv->connector; + ret =3D set_connector_edid(test, conn, + test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz, + ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz)); + KUNIT_ASSERT_EQ(test, ret, 0); + ctx =3D drm_kunit_helper_acquire_ctx_alloc(test); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx); =20 - conn =3D &priv->connector; preferred =3D find_preferred_mode(conn); KUNIT_ASSERT_NOT_NULL(test, preferred); =20 drm =3D &priv->drm; crtc =3D priv->crtc; @@ -272,15 +274,15 @@ static void drm_test_check_output_bpc_crtc_mode_chang= ed(struct kunit *test) KUNIT_ASSERT_NOT_ERR_OR_NULL(test, new_conn_state); =20 old_conn_state =3D drm_atomic_get_old_connector_state(state, conn); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, old_conn_state); =20 - new_conn_state->hdmi.output_bpc =3D 8; + new_conn_state->max_requested_bpc =3D 8; =20 KUNIT_ASSERT_NE(test, - old_conn_state->hdmi.output_bpc, - new_conn_state->hdmi.output_bpc); + old_conn_state->max_requested_bpc, + new_conn_state->max_requested_bpc); =20 ret =3D drm_atomic_check_only(state); KUNIT_ASSERT_EQ(test, ret, 0); =20 old_conn_state =3D drm_atomic_get_old_connector_state(state, conn); @@ -320,14 +322,19 @@ static void drm_test_check_output_bpc_crtc_mode_not_c= hanged(struct kunit *test) priv =3D drm_atomic_helper_connector_hdmi_init(test, BIT(HDMI_COLORSPACE_RGB), 10); KUNIT_ASSERT_NOT_NULL(test, priv); =20 + conn =3D &priv->connector; + ret =3D set_connector_edid(test, conn, + test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz, + ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz)); + KUNIT_ASSERT_EQ(test, ret, 0); + ctx =3D drm_kunit_helper_acquire_ctx_alloc(test); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx); =20 - conn =3D &priv->connector; preferred =3D find_preferred_mode(conn); KUNIT_ASSERT_NOT_NULL(test, preferred); =20 drm =3D &priv->drm; crtc =3D priv->crtc; @@ -670,11 +677,11 @@ static void drm_test_check_format_value(struct kunit = *test) 8); KUNIT_ASSERT_NOT_NULL(test, priv); =20 conn =3D &priv->connector; conn_state =3D conn->state; - KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, HDMI_COLORSPACE_RGB= ); + KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, 0); } =20 /* * Test that the value of the output format property out of reset is set * to 0, and will be computed at atomic_check time. --=20 2.44.0