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 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 65AC8FEFB7C for ; Fri, 27 Feb 2026 19:21:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2CA9F10EBFC; Fri, 27 Feb 2026 19:21:24 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b="ia18J4PH"; dkim-atps=neutral Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id ACD5D10EBF9; Fri, 27 Feb 2026 19:21:23 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1772220073; cv=none; d=zohomail.com; s=zohoarc; b=V16G2IyxSBQEmtZGu/ZWPpanB1eWageappNlvSiA3tOcgydY4VR6JLrTHzV5hm7/+vBQ8KsomH7dDoaWJ1ZkzPWlpIF0enWOlbDOpRNX8aaRiFkAQajMA4R7NtCugl949XrjGk/ejSfr43tvzWfd33x13jn2A18O8Ukw+ZvbyZ4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1772220073; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=WgsZAA03vPLPQvC4vGSXIBXCjP15MRYh/zrtI4ZTP0A=; b=h/CwTkglduHQLcwpJpLvu7dbqE1qO7uI9W31N+2dI67DjPuVyDWbVZNhuUNVcoTkArBdwzFd0dvoxiiN4QmDwij3csHiYtogsb1hhyV2eResQGiM4gLOHIagkK2xgz65Qdu2G56HdpY5w7EbTLKbxFbddLmO1/F3JQdIBUX6euw= 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=1772220073; 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:References:In-Reply-To:To:To:Cc:Cc:Reply-To; bh=WgsZAA03vPLPQvC4vGSXIBXCjP15MRYh/zrtI4ZTP0A=; b=ia18J4PHdAMjkpW/Lf0G2ikxkOS1YSvWX0J+/pvzgph/v+8Fl6nQdRE4RRx4R8WK 76lZnJOJfrQINKFmboB81tYQDUucfgzzxiTARtaVPxLoj9ByuQ/GrIdaoIzDffsd1+b HQMbnjiE9seWfoBoLI+gnKXIRMdXK/QfY43/7y3Q= Received: by mx.zohomail.com with SMTPS id 1772220071839440.65825347098655; Fri, 27 Feb 2026 11:21:11 -0800 (PST) From: Nicolas Frattaroli Date: Fri, 27 Feb 2026 20:20:10 +0100 Subject: [PATCH v9 05/19] drm/display: hdmi-state-helper: Try subsampling in mode_valid MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260227-color-format-v9-5-658c3b9db7ef@collabora.com> References: <20260227-color-format-v9-0-658c3b9db7ef@collabora.com> In-Reply-To: <20260227-color-format-v9-0-658c3b9db7ef@collabora.com> To: Harry Wentland , Leo Li , Rodrigo Siqueira , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Dmitry Baryshkov , Sascha Hauer , Rob Herring , Jonathan Corbet , Shuah Khan Cc: kernel@collabora.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-doc@vger.kernel.org, Nicolas Frattaroli X-Mailer: b4 0.14.3 X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" drm_hdmi_connector_mode_valid assumes modes are only valid if they work with RGB. The reality is more complex however: YCbCr 4:2:0 chroma-subsampled modes only require half the pixel clock that the same mode would require in RGB. This leads to drm_hdmi_connector_mode_valid rejecting perfectly valid 420-only or 420-also modes. Fix this by checking whether the mode is 420-capable first. If so, then proceed by checking it with DRM_OUTPUT_COLOR_FORMAT_YCBCR420 so long as the connector has legalized 420, otherwise error out. If the mode is not 420-capable, check with RGB as was previously always the case. Fixes: 47368ab437fd ("drm/display: hdmi: add generic mode_valid helper") Reviewed-by: Maxime Ripard Signed-off-by: Nicolas Frattaroli --- drivers/gpu/drm/display/drm_hdmi_state_helper.c | 15 ++++++++++++++- 1 file changed, 14 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 31c6d55fa995..5dc61b752e2b 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -934,8 +934,21 @@ drm_hdmi_connector_mode_valid(struct drm_connector *connector, const struct drm_display_mode *mode) { unsigned long long clock; + enum drm_output_color_format fmt; + + if (drm_mode_is_420_only(&connector->display_info, mode)) { + if (connector->ycbcr_420_allowed) + fmt = DRM_OUTPUT_COLOR_FORMAT_YCBCR420; + else + return MODE_NO_420; + } else if (drm_mode_is_420_also(&connector->display_info, mode) && + connector->ycbcr_420_allowed) { + fmt = DRM_OUTPUT_COLOR_FORMAT_YCBCR420; + } else { + fmt = DRM_OUTPUT_COLOR_FORMAT_RGB444; + } - clock = drm_hdmi_compute_mode_clock(mode, 8, DRM_OUTPUT_COLOR_FORMAT_RGB444); + clock = drm_hdmi_compute_mode_clock(mode, 8, fmt); if (!clock) return MODE_ERROR; -- 2.53.0