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 50B9BF589DD for ; Thu, 23 Apr 2026 14:22:01 +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=ZNyAefoTSUoApaDZ6nA6oDzV/WSD33AfPf5BQZbC7fg=; b=qwTxNFhcY4PKqIj2/5gfnwqzRm 5xPCkAiHAdEvpHyC7qwkOaT90o0JJ4kvgfVneiH7YMxIqL2frMxPQhmApvP0LCcBURGmf3GfBjp0l y5FWMWDFJUeQF0Z/5+0atc/udMpyGcweYX2FGUQuacAq5y1C8vxuXS8GgX7m7qy/NnM+DHKlomasQ Iwn+5dZqhNUW4awhhq6v1BKzwndJRSxjifIWnWdGJ2/tVPusM+ZzQP92Kzv/5rHD3oeq2WdSt6s0E v7pob46uj4gKMlOE0zXWEniek/WwQzzHhAn/5zITbIVoPwsoyL68uRjPg6GJRwt6TY/gv+y7bG2pe SjkTVM2Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wFuwH-0000000BoDc-2iLd; Thu, 23 Apr 2026 14:21:57 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wFuwB-0000000BoC0-26AD for linux-arm-kernel@lists.infradead.org; Thu, 23 Apr 2026 14:21:56 +0000 Received: from [127.0.1.1] (91-158-153-178.elisa-laajakaista.fi [91.158.153.178]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 977AC9A4; Thu, 23 Apr 2026 16:20:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1776954007; bh=qsLARDIVnkaD/ICi7soozFniWWJmCvAqHDdDTOWdWNc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=SH8WWtfxYgJIOmCBHZeDq6CKA0QNMeHsHVHtaHNioucGtgF0nYR5PPIpyu8C5Cq7n g1YlCQdjAVEQE938F8lzysjjjDpyTnswPOu5CLw9utjvBC1HIBevkCJ8Dax0JWRI/2 fdjio/tr30Th1oB3e6tVLpFU1IYC6+MR1v0HkHto= From: Tomi Valkeinen Date: Thu, 23 Apr 2026 17:21:12 +0300 Subject: [PATCH v10 01/11] drm/fourcc: Add warning for bad bpp MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260423-xilinx-formats-v10-1-c690c2b8ea89@ideasonboard.com> References: <20260423-xilinx-formats-v10-0-c690c2b8ea89@ideasonboard.com> In-Reply-To: <20260423-xilinx-formats-v10-0-c690c2b8ea89@ideasonboard.com> To: Vishal Sagar , Anatoliy Klymenko , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Laurent Pinchart , Michal Simek , Simon Ser Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Geert Uytterhoeven , Dmitry Baryshkov , Pekka Paalanen , Tomi Valkeinen X-Mailer: b4 0.15-dev-c25d1 X-Developer-Signature: v=1; a=openpgp-sha256; l=1792; i=tomi.valkeinen@ideasonboard.com; h=from:subject:message-id; bh=qsLARDIVnkaD/ICi7soozFniWWJmCvAqHDdDTOWdWNc=; b=owEBbQKS/ZANAwAIAfo9qoy8lh71AcsmYgBp6ir02WndvzaoJu9fVHl03maWhZDEGbC6j3mLR QkhABJgBzeJAjMEAAEIAB0WIQTEOAw+ll79gQef86f6PaqMvJYe9QUCaeoq9AAKCRD6PaqMvJYe 9SIgD/9Pd6FQKFMsX4tEdU/iPPznMxPeNc3lJQSCoeDlE2x6iS5F4CbFvjewkCTmfG2ncFxMOld K5GGNDl9aJOEGsHZ+n1jroBIFV/l7DBcQ+aPlmIrn1AfPRH85DpwH3v0iurNIexBocnCG2/J/yp sq1TPgoBZDY6BbzO5fSMhLtw7eJyqXnjHVCb2BB5xz4QgYCiWenJn8JTMl2ST2/CsLTRoBQfIBY hE4c7V9wUYeZP9lppLqk3Bb94RpBrZDQsXtPjA3WAbEmG/Ed0G/iMa4acEWK5BG0kMbqLjogp2i OQ4M8Y9w96PHcLN9cepSOJZCvk6AaCRYvcWCKInKUST0c+nSn6YhqAXMJXJtCwkC/tjWBRhXbkn DcKuCWvVxl1W6KAB+VMoyi6FZEfoCLFHxqpWSNvMcePmLovecJi7/Tpe3G5cnymiMyCJRCpvN5x 0BMI/1avkmPRYnFgXk3J6VA0fH7LHqHY/psSEGdAFR6btXL0cA41dxHEHUyD51VZTHhXE4UUISu PcHofQTqI2AyGpwANXqORqUD/6Uc0z2+wCXmNfNGk2iYZhuOZmOqJmMiOeczg0asJk0rfSzzyyh 1jaK633LPo4DWfu6UYKrPyWevm539oH81rcoUZHE35Yp91Ml6ODzvZeBoUUCF/ISrAMZzNRBtwc Ka50JNd1GuzanLg== X-Developer-Key: i=tomi.valkeinen@ideasonboard.com; a=openpgp; fpr=C4380C3E965EFD81079FF3A7FA3DAA8CBC961EF5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260423_072151_688999_D36063D1 X-CRM114-Status: GOOD ( 10.29 ) 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 drm_format_info_bpp() cannot be used for formats which do not have an integer bits-per-pixel in a pixel block. E.g. DRM_FORMAT_P030's plane 0 has three 10-bit pixels (Y components), and two padding bits, in a 4 byte block. That is 10.666... bits per pixel when considering the whole 4 byte block, which is what drm_format_info_bpp() does. Thus a driver that supports such formats cannot use drm_format_info_bpp(), It is a driver bug if this happens, but so handle wrong calls by printing a warning and returning 0. Reviewed-by: Laurent Pinchart Reviewed-by: Dmitry Baryshkov Signed-off-by: Tomi Valkeinen --- drivers/gpu/drm/drm_fourcc.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c index e0d533611040..e662aea9d105 100644 --- a/drivers/gpu/drm/drm_fourcc.c +++ b/drivers/gpu/drm/drm_fourcc.c @@ -491,12 +491,20 @@ EXPORT_SYMBOL(drm_format_info_block_height); */ unsigned int drm_format_info_bpp(const struct drm_format_info *info, int plane) { + unsigned int block_size; + if (!info || plane < 0 || plane >= info->num_planes) return 0; - return info->char_per_block[plane] * 8 / - (drm_format_info_block_width(info, plane) * - drm_format_info_block_height(info, plane)); + block_size = drm_format_info_block_width(info, plane) * + drm_format_info_block_height(info, plane); + + if (info->char_per_block[plane] * 8 % block_size) { + pr_warn("unable to return an integer bpp\n"); + return 0; + } + + return info->char_per_block[plane] * 8 / block_size; } EXPORT_SYMBOL(drm_format_info_bpp); -- 2.43.0