From patchwork Sun May 26 18:08:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Devarsh Thakkar X-Patchwork-Id: 13674330 Received: from lelv0142.ext.ti.com (lelv0142.ext.ti.com [198.47.23.249]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A88A412B143; Sun, 26 May 2024 18:09:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.23.249 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716746959; cv=none; b=MYG6PNMQD0rbGldX1EAPUYVQzXS7yHOfF/M/r8+el+nrseKCzBbsTQzulI1SMRRwhtnfY/ZQQ5KaoIRmi/i4aq3pfa8HffZF0iw58V87p9vhQc0rThNLrZwRzNP2ohrr5zGfE6sM2GxUlZkeTb+VlBbAe6a3lSjSgtnDUXO4Mjg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716746959; c=relaxed/simple; bh=Tq9RID1eGKmAb/zrMSygHUy03Gm5AHToA9chpozOKRc=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=SBhxfn4P4wm4iROuwn9mDex0Sui9YhCKHczOh/XZ/jhX+3RiWjR8uol+u6ziAxWr4GlDbe8W1hWhKRBHYY7t0urepqsde819x+Pc8OJSYYzpL3vWVeXyGNsiKDxqGMNNw39ZVhRza5PcvgOkp7fyVNgFRudwonEdSqnmkVPxyjo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=dIowYBlv; arc=none smtp.client-ip=198.47.23.249 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="dIowYBlv" Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 44QI8wBY104298; Sun, 26 May 2024 13:08:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1716746938; bh=/myx6+rpJkcV9HaO4usFwZu1ENnKeJ95GZJJe/8hHwc=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=dIowYBlvb0rbGG1vxCGjSwfcUpzc2DQtmAeaZxIkAPKNW+o5pqKwkH/o0MK2FVwf8 CjbThW8KYtbv4FrcwnNrFprOoHfCKvASrpPZfjYKfkaX0sFlPDu/4g23FzSBDrb3kU jE9JRwqdYhYdnw7pxB3PFZkGUISQGPqjoWLHnWCs= Received: from DFLE108.ent.ti.com (dfle108.ent.ti.com [10.64.6.29]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 44QI8vlc107620 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Sun, 26 May 2024 13:08:57 -0500 Received: from DFLE102.ent.ti.com (10.64.6.23) by DFLE108.ent.ti.com (10.64.6.29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Sun, 26 May 2024 13:08:57 -0500 Received: from lelvsmtp5.itg.ti.com (10.180.75.250) by DFLE102.ent.ti.com (10.64.6.23) 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; Sun, 26 May 2024 13:08:57 -0500 Received: from localhost (ti.dhcp.ti.com [172.24.227.95] (may be forged)) by lelvsmtp5.itg.ti.com (8.15.2/8.15.2) with ESMTP id 44QI8ujr097209; Sun, 26 May 2024 13:08:57 -0500 From: Devarsh Thakkar To: , , , , , , , , , , , , , , CC: , , , , , , , , , , , , , , Subject: [PATCH v9 06/10] math.h: Add macros for rounding to closest value Date: Sun, 26 May 2024 23:38:56 +0530 Message-ID: <20240526180856.1124470-1-devarsht@ti.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20240526175655.1093707-1-devarsht@ti.com> References: <20240526175655.1093707-1-devarsht@ti.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Add below rounding related macros: round_closest_up(x, y) : Rounds x to closest multiple of y where y is a power of 2, with a preference to round up in case two nearest values are possible. round_closest_down(x, y) : Rounds x to closest multiple of y where y is a power of 2, with a preference to round down in case two nearest values are possible. roundclosest(x, y) : Rounds x to closest multiple of y, this macro should generally be used only when y is not multiple of 2 as otherwise round_closest* macros should be used which are much faster. Examples: * round_closest_up(17, 4) = 16 * round_closest_up(15, 4) = 16 * round_closest_up(14, 4) = 16 * round_closest_down(17, 4) = 16 * round_closest_down(15, 4) = 16 * round_closest_down(14, 4) = 12 * roundclosest(21, 5) = 20 * roundclosest(19, 5) = 20 * roundclosest(17, 5) = 15 Signed-off-by: Devarsh Thakkar --- NOTE: This patch is inspired from the Mentor Graphics IPU driver [1] which uses similar macro locally and which is updated in further patch in the series 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 V9: - No change V8: - Add new macro to round to nearest value for non-multiple of 2 - Update commit message as suggested: V1->V6 (No change, patch introduced in V7) --- include/linux/math.h | 65 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) diff --git a/include/linux/math.h b/include/linux/math.h index dd4152711de7..e2cc3769ed0e 100644 --- a/include/linux/math.h +++ b/include/linux/math.h @@ -34,6 +34,54 @@ */ #define round_down(x, y) ((x) & ~__round_mask(x, y)) +/** + * round_closest_up - round closest to be multiple of specified value (which is + * power of 2) with preference to rounding up + + * @x: the value to round + * @y: multiple to round closest to (must be a power of 2) + * + * Rounds @x to closest multiple of @y (which must be a power of 2). + * The value can be either rounded up or rounded down depending upon rounded + * value's closeness to the specified value. If there are two closest possible + * values, i.e. the difference between the specified value and it's rounded up + * and rounded down values is same then preference is given to rounded up + * value. + * + * To perform arbitrary rounding to closest value (not multiple of 2), use + * roundclosest(). + * + * 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 closest to be multiple of specified value (which + * is power of 2) with preference to rounding down + * + * @x: the value to round + * @y: multiple to round closest to (must be a power of 2) + * + * Rounds @x to closest multiple of @y (which must be a power of 2). + * The value can be either rounded up or rounded down depending upon rounded + * value's closeness to the specified value. If there are two closest possible + * values, i.e. the difference between the specified value and it's rounded up + * and rounded down values is same then preference is given to rounded up + * value. + * + * To perform arbitrary rounding to closest value (not multiple of 2), use + * roundclosest(). + * + * 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) \ @@ -77,6 +125,23 @@ } \ ) +/** + * roundclosest - round to nearest multiple + * @x: the value to round + * @y: multiple to round nearest to + * + * Rounds @x to nearest multiple of @y. + * The rounded value can be greater than or less than @x depending + * upon it's nearness to @x. If @y will always be a power of 2, consider + * using the faster round_closest_up() or round_closest_down(). + * + * Examples : + * roundclosest(21, 5) = 20 + * roundclosest(19, 5) = 20 + * roundclosest(17, 5) = 15 + */ +#define roundclosest(x, y) rounddown((x) + (y) / 2, (y)) + /* * Divide positive or negative dividend by positive or negative divisor * and round to closest integer. Result is undefined for negative