From patchwork Tue Jul 1 09:30:47 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiko Stuebner X-Patchwork-Id: 4457461 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 6C0589F358 for ; Tue, 1 Jul 2014 09:31:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 73F57202F8 for ; Tue, 1 Jul 2014 09:31:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 88A72203F1 for ; Tue, 1 Jul 2014 09:31:36 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1X1uNu-00048u-CJ; Tue, 01 Jul 2014 09:29:54 +0000 Received: from gloria.sntech.de ([95.129.55.99]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1X1uNq-0003v1-PS for linux-arm-kernel@lists.infradead.org; Tue, 01 Jul 2014 09:29:52 +0000 Received: from ip9234425c.dynamic.kabel-deutschland.de ([146.52.66.92] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1X1uNN-0003Gy-Kn; Tue, 01 Jul 2014 11:29:21 +0200 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Gabriel Fernandez , Mike Turquette Subject: [PATCH v4.2 01/13] clk: composite: support determine_rate using rate_ops->round_rate + mux_ops->set_parent Date: Tue, 01 Jul 2014 11:30:47 +0200 Message-ID: <2161459.ftBWKNzjEe@diego> User-Agent: KMail/4.11.5 (Linux/3.13-1-amd64; KDE/4.11.3; x86_64; ; ) In-Reply-To: References: <1808429.dNxms7FR7U@diego> <2257244.FrPXR4AKP7@diego> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140701_022951_004053_D3865B2E X-CRM114-Status: GOOD ( 14.83 ) X-Spam-Score: -0.0 (/) Cc: Emilio =?ISO-8859-1?Q?L=F3pez?= , Max Schwarz , Gabriel Fernandez , "linux-arm-kernel@lists.infradead.org" , Boris BREZILLON X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Boris BREZILLON In case the rate_hw does not implement determine_rate, but only round_rate we fallback to best_parent selection if mux_hw is present and support reparenting. Signed-off-by: Boris BREZILLON This also fixes a rate calculation problem when using the standard div and mux ops, as in this case currently only the mux->determine_rate is used in the composite rate calculation. So when for example the composite clock has two parents at 600 and 800MHz, the requested rate is 75MHz, which the divider could provide, without this change the rate would be set 600MHz ignoring the divider completely. This may be way out of spec for the component. [fixed the output to actually return a rate instead of the diff] Signed-off-by: Heiko Stuebner --- changes since v4.1: - forgot the From override, Boris is the original author changes since v4: - address comments from Gabriel Fernandez - use abs() - init best_rate drivers/clk/clk-composite.c | 48 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c index 57a078e..9548bfc 100644 --- a/drivers/clk/clk-composite.c +++ b/drivers/clk/clk-composite.c @@ -64,11 +64,56 @@ static long clk_composite_determine_rate(struct clk_hw *hw, unsigned long rate, const struct clk_ops *mux_ops = composite->mux_ops; struct clk_hw *rate_hw = composite->rate_hw; struct clk_hw *mux_hw = composite->mux_hw; + struct clk *parent; + unsigned long parent_rate; + long tmp_rate, best_rate = 0; + unsigned long rate_diff; + unsigned long best_rate_diff = ULONG_MAX; + int i; if (rate_hw && rate_ops && rate_ops->determine_rate) { rate_hw->clk = hw->clk; return rate_ops->determine_rate(rate_hw, rate, best_parent_rate, best_parent_p); + } else if (rate_hw && rate_ops && rate_ops->round_rate && + mux_hw && mux_ops && mux_ops->set_parent) { + *best_parent_p = NULL; + + if (__clk_get_flags(hw->clk) & CLK_SET_RATE_NO_REPARENT) { + *best_parent_p = clk_get_parent(mux_hw->clk); + *best_parent_rate = __clk_get_rate(*best_parent_p); + + return rate_ops->round_rate(rate_hw, rate, + best_parent_rate); + } + + for (i = 0; i < __clk_get_num_parents(mux_hw->clk); i++) { + parent = clk_get_parent_by_index(mux_hw->clk, i); + if (!parent) + continue; + + parent_rate = __clk_get_rate(parent); + + tmp_rate = rate_ops->round_rate(rate_hw, rate, + &parent_rate); + if (tmp_rate < 0) + continue; + + rate_diff = abs(rate - tmp_rate); + + if (!rate_diff || !*best_parent_p + || best_rate_diff > rate_diff) { + *best_parent_p = parent; + *best_parent_rate = parent_rate; + best_rate_diff = rate_diff; + best_rate = tmp_rate; + } + + if (!rate_diff) + return rate; + } + + return best_rate; } else if (mux_hw && mux_ops && mux_ops->determine_rate) { mux_hw->clk = hw->clk; return mux_ops->determine_rate(mux_hw, rate, best_parent_rate, @@ -196,7 +241,8 @@ struct clk *clk_register_composite(struct device *dev, const char *name, composite->rate_hw = rate_hw; composite->rate_ops = rate_ops; clk_composite_ops->recalc_rate = clk_composite_recalc_rate; - if (rate_ops->determine_rate) + if (rate_ops->determine_rate || + (rate_ops->round_rate && clk_composite_ops->set_parent)) clk_composite_ops->determine_rate = clk_composite_determine_rate; }