From patchwork Sun Nov 4 18:26:39 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: 10667095 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A46F513B5 for ; Sun, 4 Nov 2018 18:42:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 96330296A9 for ; Sun, 4 Nov 2018 18:42:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 89C64296B3; Sun, 4 Nov 2018 18:42:53 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 35DDE296A9 for ; Sun, 4 Nov 2018 18:42:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C7E6B6E08D; Sun, 4 Nov 2018 18:42:32 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.siol.net (mailoutvs27.siol.net [185.57.226.218]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7B5446E02E for ; Sun, 4 Nov 2018 18:27:38 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mail.siol.net (Postfix) with ESMTP id B710652126A; Sun, 4 Nov 2018 19:27:36 +0100 (CET) X-Virus-Scanned: amavisd-new at psrvmta11.zcs-production.pri Received: from mail.siol.net ([127.0.0.1]) by localhost (psrvmta11.zcs-production.pri [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id wN4M1pcLPRoh; Sun, 4 Nov 2018 19:27:36 +0100 (CET) Received: from mail.siol.net (localhost [127.0.0.1]) by mail.siol.net (Postfix) with ESMTPS id 4A46F521256; Sun, 4 Nov 2018 19:27:36 +0100 (CET) Received: from localhost.localdomain (cpe1-8-82.cable.triera.net [213.161.8.82]) (Authenticated sender: 031275009) by mail.siol.net (Postfix) with ESMTPSA id 840BB52126A; Sun, 4 Nov 2018 19:27:33 +0100 (CET) From: Jernej Skrabec To: maxime.ripard@bootlin.com, wens@csie.org Subject: [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent rate when allowed Date: Sun, 4 Nov 2018 19:26:39 +0100 Message-Id: <20181104182705.18047-3-jernej.skrabec@siol.net> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181104182705.18047-1-jernej.skrabec@siol.net> References: <20181104182705.18047-1-jernej.skrabec@siol.net> MIME-Version: 1.0 X-Mailman-Approved-At: Sun, 04 Nov 2018 18:42:21 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, sboyd@kernel.org, mturquette@baylibre.com, jernej.skrabec@siol.net, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, airlied@linux.ie, linux-sunxi@googlegroups.com, robh+dt@kernel.org, Laurent.pinchart@ideasonboard.com, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Currently MP clocks don't consider adjusting parent rate even if they are allowed to do so. Such behaviour considerably lowers amount of possible rates, which is very inconvenient when such clock is used for pixel clock, for example. In order to improve the situation, adjusting parent rate is considered when allowed. This code is inspired by clk_divider_bestdiv() function, which does basically the same thing for different clock type. Signed-off-by: Jernej Skrabec --- drivers/clk/sunxi-ng/ccu_mp.c | 64 +++++++++++++++++++++++++++++++++-- 1 file changed, 62 insertions(+), 2 deletions(-) diff --git a/drivers/clk/sunxi-ng/ccu_mp.c b/drivers/clk/sunxi-ng/ccu_mp.c index 5d0af4051737..0357349eb767 100644 --- a/drivers/clk/sunxi-ng/ccu_mp.c +++ b/drivers/clk/sunxi-ng/ccu_mp.c @@ -40,6 +40,61 @@ static void ccu_mp_find_best(unsigned long parent, unsigned long rate, *p = best_p; } +static unsigned long ccu_mp_find_best_with_parent_adj(struct clk_hw *hw, + unsigned long *parent, + unsigned long rate, + unsigned int max_m, + unsigned int max_p) +{ + unsigned long parent_rate_saved; + unsigned long parent_rate, now; + unsigned long best_rate = 0; + unsigned int _m, _p, div; + unsigned long maxdiv; + + parent_rate_saved = *parent; + + /* + * The maximum divider we can use without overflowing + * unsigned long in rate * m * p below + */ + maxdiv = max_m * max_p; + maxdiv = min(ULONG_MAX / rate, maxdiv); + + for (_p = 1; _p <= max_p; _p <<= 1) { + for (_m = 1; _m <= max_m; _m++) { + div = _m * _p; + + if (div > maxdiv) + break; + + if (rate * div == parent_rate_saved) { + /* + * It's the most ideal case if the requested + * rate can be divided from parent clock without + * needing to change parent rate, so return the + * divider immediately. + */ + *parent = parent_rate_saved; + return rate; + } + + parent_rate = clk_hw_round_rate(hw, rate * div); + now = parent_rate / div; + + if (now <= rate && now > best_rate) { + best_rate = now; + *parent = parent_rate; + + if (now == rate) + return rate; + } + } + } + + return best_rate; +} + static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux, struct clk_hw *hw, unsigned long *parent_rate, @@ -56,8 +111,13 @@ static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux, max_m = cmp->m.max ?: 1 << cmp->m.width; max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1); - ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p); - rate = *parent_rate / p / m; + if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) { + ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p); + rate = *parent_rate / p / m; + } else { + rate = ccu_mp_find_best_with_parent_adj(hw, parent_rate, rate, + max_m, max_p); + } if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV) rate /= cmp->fixed_post_div;