From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 42501C982ED for ; Mon, 21 Sep 2026 15:55:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=I5L+bsoWmPLekEYM66FjXrtQ+U3z611xrc5MNXFSuEI=; b=IPkzmNfaXZKzhhac8Dzr08OV29 4VY0HPQXNJozoZPqIF/R2XSAOKkkv097Uu4QjozYhv7LTBdXIrZdwyfY768YbALpmUHKSgizLI0ci Cdog6Wue7H7b5SKL514cRdIMRQD2ZAeGPlMZQr2bO9cV32O1FxPbWNwLcrRsrBLSk5fljODHOU0rq knDTIrIZtgimiKt6jCslTZGfwQBqN27/U2efsZ18b+Vzvuj/In5tQitakR6+9/CXeKHlGbwzxM+w0 QcuupbbN1KLivEVqflxP2vvg5zpEArr7+XFCUtR7GTm/GBBKfWl22WYND+V9sLvL7rikSPbNaiv/Z R21s3+Xg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8gM0-00000002jHh-3fpS; Mon, 21 Sep 2026 15:54:53 +0000 Received: from sender4-pp-f112.zoho.com ([136.143.188.112]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8gLc-00000002igD-1bGr; Mon, 21 Sep 2026 15:54:30 +0000 ARC-Seal: i=1; a=rsa-sha256; t=1790006035; cv=none; d=zohomail.com; s=zohoarc; b=Qm70zm2P7Z3dLQEsA8wBm3JW+mpnGUIIXH2wYf8nn1LCGxEKVpcSav39j6zsVLlpiLYNDK+bTANoGSAOuZOvePK4LrQ+v5rDEZOQO2FxHnSmaa5plus13wmzwYsXtxdLUs9WUGwom2eVGSma1EfbqC5tvsM5J46L6C8WpPYO+j0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1790006035; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=I5L+bsoWmPLekEYM66FjXrtQ+U3z611xrc5MNXFSuEI=; b=lOP9Cj+YJLxWf1N5VgiRomX/lqnO7uNB+42y+RG1F4Qt/A4czPYGAI2qjys4z2/Hr1Kz82zrjihmw0Y2fYToeSZ0E10ebYaQ1+KcEkI7/lUv8Wsu0gt83Ago97pkJc3meG+cvbTsWM274fyPyUavP+ZgGGWwG89EygSkAwI5NTA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=nicolas.frattaroli@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1790006035; s=zohomail; d=collabora.com; i=nicolas.frattaroli@collabora.com; h=From:From:Date:Date:Subject:Subject:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id:Message-Id:In-Reply-To:To:To:Cc:Cc:Reply-To; bh=I5L+bsoWmPLekEYM66FjXrtQ+U3z611xrc5MNXFSuEI=; b=ko/84+RVAHXZLFMZhNu3TYTpih0LU9lzYu2K3dwFnPB4HL+Ii6QQI364DC0w3kaY NValglXTbMlKMbtRRk3hka1UNayLjTXrmobdhsIw8kroXnQ6Pb+c7hEAWAD/xME4dTH uQkeVtPXduSDJPpW6jeinF6lTdCAVNC24RnNsBOI= Received: by smtp.zohomail.com with SMTPS id 1790006033715880.1589251682541; Mon, 21 Sep 2026 08:53:53 -0700 (PDT) From: Nicolas Frattaroli Date: Mon, 21 Sep 2026 17:51:46 +0200 Subject: [PATCH RFC 20/25] drm/connector: hdmi: Add QMS state validation and computation MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260921-vrr-limiter-uapi-v1-20-2fcd7d011646@collabora.com> References: <20260921-vrr-limiter-uapi-v1-0-2fcd7d011646@collabora.com> In-Reply-To: <20260921-vrr-limiter-uapi-v1-0-2fcd7d011646@collabora.com> To: "Borah, Chaitanya Kumar" , Leo Li , Daniel Stone , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Helge Deller , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, kernel@collabora.com, Derek Foreman , wayland-devel@lists.freedesktop.org, Nicolas Frattaroli X-Mailer: b4 0.15.2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260921_085428_932149_5B1EA04C X-CRM114-Status: GOOD ( 21.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add the necessary code to the HDMI state helpers' hdmi_validate_vrr function in order to check and derive the state necessary for HDMI Quick Media Switching (QMS) support. Co-developed-by: Derek Foreman Signed-off-by: Derek Foreman Signed-off-by: Nicolas Frattaroli --- drivers/gpu/drm/display/drm_hdmi_state_helper.c | 103 +++++++++++++++++++++++- 1 file changed, 102 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c index 7237070fc9ee..d392ae2908f9 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -2,6 +2,7 @@ #include #include +#include #include #include @@ -950,6 +951,26 @@ hdmi_generate_infoframes(const struct drm_connector *connector, return 0; } +static const struct { + u8 tfr_byte; + u32 rate_n; + u32 rate_d; +} hdmi_qms_tfrs[] = { + { 1, 24000, 1001 }, + { 2, 24, 1 }, + { 3, 25, 1 }, + { 4, 30000, 1001 }, + { 5, 30, 1 }, + { 6, 48000, 1001 }, + { 7, 48, 1 }, + { 8, 50, 1 }, + { 9, 60000, 1001 }, + { 10, 60, 1 }, + { 11, 100, 1 }, + { 12, 120000, 1001 }, + { 13, 120, 1 }, +}; + /** * cmp_fraction - compares two fractional numbers * @a: numerator of the first fraction @@ -988,6 +1009,69 @@ static int cmp_fraction(u32 a, u32 b, u32 c, u32 d) return 0; } +/** + * hdmi_validate_qms - Validate HDMI QMS state + * @crtc_state: pointer to a &struct drm_crtc_state to run validation on + * @info: pointer to a &struct drm_display_info of the accompanying connector + * + * Validate that the drm_crtc_vrr_state.vrr_min_numerator and + * drm_crtc_vrr_state.vrr_min_denominator are acceptable for HDMI QMS, and check + * that the display is HDMI QMS capable. + * + * Returns: + * - Negative errno on failure + * - the corresponding QMS signaling byte for the target frame rate otherwise + */ +static int hdmi_validate_qms(struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + const struct drm_display_info *info) +{ + u32 rate_n = crtc_state->vrr_state.vrr_min_n; + u32 rate_d = crtc_state->vrr_state.vrr_min_d; + u32 min_rate_n, max_rate; + u32 g, i; + + if (!conn_state->hdmi.qms_enabled) + return 0; + + if (!info->hdmi.qms_capable) + return -EOPNOTSUPP; + + if (!drm_crtc_helper_vrr_is_fixed_rate(&crtc_state->vrr_state)) + return -EINVAL; + + if (info->hdmi.qms_tfr_min) + min_rate_n = 24000; + else + min_rate_n = info->monitor_range.min_vfreq * 1000; + + if (info->hdmi.qms_tfr_max) + max_rate = info->monitor_range.max_vfreq; + else + max_rate = 60; + + g = gcd(rate_n, rate_d); + if (g != 1) { + rate_n /= g; + rate_d /= g; + } + + if (!rate_d) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(hdmi_qms_tfrs); i++) { + if (cmp_fraction(min_rate_n, 1001, hdmi_qms_tfrs[i].rate_n, + hdmi_qms_tfrs[i].rate_d) > 0) + continue; + if (rate_n == hdmi_qms_tfrs[i].rate_n && + rate_d == hdmi_qms_tfrs[i].rate_d && + cmp_fraction(rate_n, rate_d, max_rate, 1) <= 0) + return hdmi_qms_tfrs[i].tfr_byte; + } + + return -EINVAL; +} + static int hdmi_calculate_vtotal(const struct drm_display_mode *mode, u32 rate_n, u32 rate_d, u16 *out_vtotal, u32 *out_denom, u32 *out_frame_err) @@ -1093,6 +1177,8 @@ static int hdmi_validate_vrr(struct drm_connector *connector, { struct drm_connector_state *new_conn_state = drm_atomic_get_new_connector_state(state, connector); + struct drm_connector_state *old_conn_state = + drm_atomic_get_old_connector_state(state, connector); struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc); struct drm_crtc_state *old_crtc_state = @@ -1113,6 +1199,7 @@ static int hdmi_validate_vrr(struct drm_connector *connector, /* Save on the expensive vic lookup, if nothing else. */ if (!new_crtc_state->mode_changed && + !new_crtc_state->connectors_changed && old_crtc_state->vrr_enabled && old_vrr_state->vrr_min_n == vrr_state->vrr_min_n && old_vrr_state->vrr_min_d == vrr_state->vrr_min_d && @@ -1143,7 +1230,9 @@ static int hdmi_validate_vrr(struct drm_connector *connector, max_vfreq_n = mode_refresh; is_fixed = drm_crtc_helper_vrr_is_fixed_rate(vrr_state); - if (is_fixed && info->hdmi.cinema_vrr) + if (is_fixed && (info->hdmi.cinema_vrr || (info->hdmi.qms_tfr_min && + new_conn_state->hdmi.qms_enabled && + info->hdmi.qms_capable))) min_vfreq_n = 24; if (!min_vfreq_n) { @@ -1165,6 +1254,18 @@ static int hdmi_validate_vrr(struct drm_connector *connector, return ret; } + ret = hdmi_validate_qms(new_crtc_state, new_conn_state, info); + if (ret < 0) { + drm_dbg_kms(dev, "Invalid QMS rate: %pe\n", ERR_PTR(ret)); + return ret; + } + + new_conn_state->hdmi.qms_tfr_byte = ret; + if (new_conn_state->hdmi.qms_tfr_byte != old_conn_state->hdmi.qms_tfr_byte) + vrr_state->dynamic = true; + else + vrr_state->dynamic = false; + if (!is_fixed) { vrr_state->dynamic = true; -- 2.55.0