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 059C8D116F9 for ; Mon, 1 Dec 2025 06:36:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 89ACA10E2CB; Mon, 1 Dec 2025 06:35:53 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="RfI6VXlu"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) by gabe.freedesktop.org (Postfix) with ESMTPS id 73C0810E0FE; Mon, 1 Dec 2025 06:35:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1764570952; x=1796106952; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=OUTdsmcWH9SUMAIl1srrZz9ziKWRPpDdI06sB9PAJDk=; b=RfI6VXluMJeEZ5z2ouehgLckHirmA78xnsmoDdxiyR2LnoQgqxifps6w nM+x3YggXsvoKIcXnWQNnxAwhydKnhix8LOycpWpDUPjLEhkxhc6BMmnq ttdDMbjJC9sMymMLKvAzbZbNMXMu2OA/lDdsk5pNaMqEfaKlQmcHrk0Gk SHQ3N+lEWIBAHa1WvnMSmI9Ut6+D1If5J9GCZHu2Dz5aYBB0JNbWLsHO+ qFRdAyNLYZfwKViY6IIo9RQkroSKzJWfo8a+LSa6gpbgEC33uXLey7I2c 6KjpgfOx0bLwC7y+dIARmpM/jw+wAgRO9Mo4oTA0NMc+eXeDEWloW9L4J Q==; X-CSE-ConnectionGUID: sYoFRLn1RzCAxM6QWEvntA== X-CSE-MsgGUID: W8LagyAzQjqLfYqKni6Zaw== X-IronPort-AV: E=McAfee;i="6800,10657,11629"; a="66663198" X-IronPort-AV: E=Sophos;i="6.20,240,1758610800"; d="scan'208";a="66663198" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2025 22:35:51 -0800 X-CSE-ConnectionGUID: LIVsdadDTAmpWSjPtvs2Hw== X-CSE-MsgGUID: /kiPVWAySzi/bQcMWuMk7A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,240,1758610800"; d="scan'208";a="193806067" Received: from cfl-desktop.iind.intel.com ([10.190.239.20]) by orviesa009.jf.intel.com with ESMTP; 30 Nov 2025 22:35:31 -0800 From: Uma Shankar To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: chaitanya.kumar.borah@intel.com, ville.syrjala@linux.intel.com, pekka.paalanen@collabora.com, contact@emersion.fr, harry.wentland@amd.com, mwen@igalia.com, jadahl@redhat.com, sebastian.wick@redhat.com, swati2.sharma@intel.com, alex.hung@amd.com, jani.nikula@intel.com, suraj.kandpal@intel.com, Uma Shankar Subject: [v7 06/15] drm/i915/color: Preserve sign bit when int_bits is Zero Date: Mon, 1 Dec 2025 12:16:46 +0530 Message-ID: <20251201064655.3579280-7-uma.shankar@intel.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20251201064655.3579280-1-uma.shankar@intel.com> References: <20251201064655.3579280-1-uma.shankar@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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" From: Chaitanya Kumar Borah When int_bits == 0, we lose the sign bit when we do the range check and apply the mask. Fix this by ensuring a minimum of one integer bit, which guarantees space for the sign bit in fully fractional representations (e.g. S0.12) Reviewed-by: Suraj Kandpal Signed-off-by: Chaitanya Kumar Borah Signed-off-by: Uma Shankar --- drivers/gpu/drm/i915/display/intel_color.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c index 33fe5c9b4663..81b87fed8878 100644 --- a/drivers/gpu/drm/i915/display/intel_color.c +++ b/drivers/gpu/drm/i915/display/intel_color.c @@ -613,6 +613,8 @@ static u16 ctm_to_twos_complement(u64 coeff, int int_bits, int frac_bits) if (CTM_COEFF_NEGATIVE(coeff)) c = -c; + int_bits = max(int_bits, 1); + c = clamp(c, -(s64)BIT(int_bits + frac_bits - 1), (s64)(BIT(int_bits + frac_bits - 1) - 1)); -- 2.50.1