From patchwork Wed Feb 14 20:08:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Jernej_=C5=A0krabec?= X-Patchwork-Id: 10219861 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A2312601C2 for ; Wed, 14 Feb 2018 20:10:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8CFA128BBA for ; Wed, 14 Feb 2018 20:10:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8011228B77; Wed, 14 Feb 2018 20:10:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id EFFA828CEA for ; Wed, 14 Feb 2018 20:10:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=1pPaKzhD5fgAdBxDBrW6dmI1itN6K85LjihM8hA/6uk=; b=AzpUthRcM6Ne3XojTzFPYeAHRL LC/eTUZXkxpxab2d/r7Gm9ROTJ+D4iPkzbI++4wofbK+QZu+7wwVtGzGo1ycaGeMgPhgOqTtxEv+v ZpACMFg3+MvePgD0AV9kEIgX51wIRNGNkmXFfI79s6klPBdSHCl6dDzXKVcuQnW9Ne+asVXLmJlgz e9NMsGp21dagOmr6aM7uOzYPgGe0kF1hrOe72fvo1CN+zEXYNupIkth+LxrzvMCi4bMuR5v2k3Z0A AbWWs9o0NzvtoPnjiv11tdHHUbUW3Osku781mHI14U8QKTts99w9c3M7op9sqli6FMLvQ1xwAT+wE y8qq4Exw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1em3NN-0000B4-Pl; Wed, 14 Feb 2018 20:09:57 +0000 Received: from mailoutvs4.siol.net ([213.250.19.137] helo=mail.siol.net) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1em3NG-0008Ua-WC for linux-arm-kernel@lists.infradead.org; Wed, 14 Feb 2018 20:09:53 +0000 Received: from localhost (localhost [127.0.0.1]) by mail.siol.net (Zimbra) with ESMTP id C17BE52077E; Wed, 14 Feb 2018 21:09:36 +0100 (CET) X-Virus-Scanned: amavisd-new at psrvmta12.zcs-production.pri Received: from mail.siol.net ([127.0.0.1]) by localhost (psrvmta12.zcs-production.pri [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id yk6rpFvPeAL6; Wed, 14 Feb 2018 21:09:36 +0100 (CET) Received: from mail.siol.net (localhost [127.0.0.1]) by mail.siol.net (Zimbra) with ESMTPS id 2DA3F52074C; Wed, 14 Feb 2018 21:09:36 +0100 (CET) Received: from localhost.localdomain (cpe-86-58-68-135.ftth.triera.net [86.58.68.135]) (Authenticated sender: 031275009) by mail.siol.net (Zimbra) with ESMTPSA id AC2A552077E; Wed, 14 Feb 2018 21:09:33 +0100 (CET) From: Jernej Skrabec To: maxime.ripard@free-electrons.com, wens@csie.org, airlied@linux.ie, robh+dt@kernel.org, mark.rutland@arm.com, mturquette@baylibre.com, sboyd@kernel.org, architt@codeaurora.org, a.hajda@samsung.com, Laurent.pinchart@ideasonboard.com, narmstrong@baylibre.com, Jose.Abreu@synopsys.com Subject: [PATCH v5 02/12] clk: sunxi-ng: Use u64 for calculation of nkmp rate Date: Wed, 14 Feb 2018 21:08:56 +0100 Message-Id: <20180214200906.31509-3-jernej.skrabec@siol.net> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180214200906.31509-1-jernej.skrabec@siol.net> References: <20180214200906.31509-1-jernej.skrabec@siol.net> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180214_120951_266549_0D42A3C1 X-CRM114-Status: UNSURE ( 8.95 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, jernej.skrabec@siol.net, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-sunxi@googlegroups.com, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP When parent rate is 24MHz and multiplier N >= 180, intermediate clock rate doesn't fit in 32 bit variable anymore. Because of that, introduce function for calculating clock rate which uses 64 bit variable for intermediate result. Acked-by: Maxime Ripard Signed-off-by: Jernej Skrabec --- drivers/clk/sunxi-ng/ccu_nkmp.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c index a99068a08315..c3f6fe7be565 100644 --- a/drivers/clk/sunxi-ng/ccu_nkmp.c +++ b/drivers/clk/sunxi-ng/ccu_nkmp.c @@ -20,6 +20,18 @@ struct _ccu_nkmp { unsigned long p, min_p, max_p; }; +static unsigned long ccu_nkmp_calc_rate(unsigned long parent, + unsigned long n, unsigned long k, + unsigned long m, unsigned long p) +{ + u64 rate = parent; + + rate *= n * k; + do_div(rate, m * p); + + return rate; +} + static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate, struct _ccu_nkmp *nkmp) { @@ -33,7 +45,9 @@ static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate, for (_p = nkmp->min_p; _p <= nkmp->max_p; _p <<= 1) { unsigned long tmp_rate; - tmp_rate = parent * _n * _k / (_m * _p); + tmp_rate = ccu_nkmp_calc_rate(parent, + _n, _k, + _m, _p); if (tmp_rate > rate) continue; @@ -107,7 +121,7 @@ static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw, p = reg >> nkmp->p.shift; p &= (1 << nkmp->p.width) - 1; - return (parent_rate * n * k >> p) / m; + return ccu_nkmp_calc_rate(parent_rate, n, k, m, 1 << p); } static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate, @@ -127,7 +141,8 @@ static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate, ccu_nkmp_find_best(*parent_rate, rate, &_nkmp); - return *parent_rate * _nkmp.n * _nkmp.k / (_nkmp.m * _nkmp.p); + return ccu_nkmp_calc_rate(*parent_rate, _nkmp.n, _nkmp.k, + _nkmp.m, _nkmp.p); } static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,