From patchwork Thu May 9 18:39:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Devarsh Thakkar X-Patchwork-Id: 13660430 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 9DC85C10F1A for ; Thu, 9 May 2024 21:18:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 70C6110F2B7; Thu, 9 May 2024 21:18:27 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=ti.com header.i=@ti.com header.b="Y6l4wMuU"; dkim-atps=neutral X-Greylist: delayed 9499 seconds by postgrey-1.36 at gabe; Thu, 09 May 2024 21:18:25 UTC Received: from lelv0142.ext.ti.com (lelv0142.ext.ti.com [198.47.23.249]) by gabe.freedesktop.org (Postfix) with ESMTPS id E1BD110F2B7 for ; Thu, 9 May 2024 21:18:25 +0000 (UTC) Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 449Ids7A090810; Thu, 9 May 2024 13:39:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1715279994; bh=lrdTPlSx5uWnTmoVruaPcAiqQdb2LlFFka9SllqeKfQ=; h=From:To:CC:Subject:Date; b=Y6l4wMuU3sCR4/pnLAByHJRo+7spyl3CQdZm7bJXqaXDi1ofG08qVgz0FQKnTG0Hu qmlmptMVUmE2iB6iWIyRXzeeieINGClAv+9uCGAkJ57bhGflIj10+RICSo4kjYl/6N MU3rJySLo7EwN235+EacWkv1CBtLRqNqe5p0CMkw= Received: from DLEE112.ent.ti.com (dlee112.ent.ti.com [157.170.170.23]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 449Idsjr028411 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 9 May 2024 13:39:54 -0500 Received: from DLEE114.ent.ti.com (157.170.170.25) by DLEE112.ent.ti.com (157.170.170.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Thu, 9 May 2024 13:39:54 -0500 Received: from lelvsmtp6.itg.ti.com (10.180.75.249) by DLEE114.ent.ti.com (157.170.170.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Thu, 9 May 2024 13:39:54 -0500 Received: from localhost (ti.dhcp.ti.com [172.24.227.95] (may be forged)) by lelvsmtp6.itg.ti.com (8.15.2/8.15.2) with ESMTP id 449IdrZA004938; Thu, 9 May 2024 13:39:53 -0500 From: Devarsh Thakkar To: , , , , , , , , , , , , , , CC: , , , , , , , , , , , , Subject: [PATCH v7 6/8] math.h Add macros to round to closest specified power of 2 Date: Fri, 10 May 2024 00:09:52 +0530 Message-ID: <20240509183952.4064331-1-devarsht@ti.com> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Add macros to round to nearest specified power of 2. Two macros are added : round_closest_up and round_closest_down which round up to nearest multiple of 2 with a preference to round up or round down respectively if there are two possible nearest values to the given number. This patch is inspired from the Mentor Graphics IPU driver [1] which uses similar macro locally and which can be updated to use this generic macro instead along with other drivers having similar requirements. [1]: https://elixir.bootlin.com/linux/v6.8.9/source/drivers/gpu/ipu-v3/ipu-image-convert.c#L480 Signed-off-by: Devarsh Thakkar --- V1->V6 (No change, patch introduced in V7) --- include/linux/math.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/include/linux/math.h b/include/linux/math.h index dd4152711de7..82ee3265c910 100644 --- a/include/linux/math.h +++ b/include/linux/math.h @@ -34,6 +34,42 @@ */ #define round_down(x, y) ((x) & ~__round_mask(x, y)) +/** + * round_closest_up - round to nearest specified power of 2 with preference + * to rounding up + * @x: the value to round + * @y: multiple to round to (must be a power of 2) + * + * Rounds @x to nearest multiple of @y (which must be a power of 2). + * The rounded value can be greater than or less than @x depending + * upon it's nearness to @x. If there are two nearest possible values, + * then preference will be given to the greater value. + * + * Examples : + * round_closest_up(17, 4) = 16 + * round_closest_up(15, 4) = 16 + * round_closest_up(14, 4) = 16 + */ +#define round_closest_up(x, y) round_down((x) + (y) / 2, (y)) + +/** + * round_closest_down - round to nearest specified power of 2 with preference + * to rounding down + * @x: the value to round + * @y: multiple to round down to (must be a power of 2) + * + * Rounds @x to nearest multiple of @y (which must be a power of 2). + * The rounded value can be greater than or less than @x depending + * upon it's nearness to @x. If there are two nearest possible values, + * then preference will be given to the lesser value. + * + * Examples : + * round_closest_down(17, 4) = 16 + * round_closest_down(15, 4) = 16 + * round_closest_down(14, 4) = 12 + */ +#define round_closest_down(x, y) round_up((x) - (y) / 2, (y)) + #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP #define DIV_ROUND_DOWN_ULL(ll, d) \