From patchwork Thu Aug 14 12:11:27 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomeu Vizoso X-Patchwork-Id: 4723881 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 2A1D69F375 for ; Thu, 14 Aug 2014 12:14:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E03B0201E4 for ; Thu, 14 Aug 2014 12:14:41 +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 AB9802015A for ; Thu, 14 Aug 2014 12:14:40 +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 1XHtty-0007g7-So; Thu, 14 Aug 2014 12:13:06 +0000 Received: from mail-wg0-x22b.google.com ([2a00:1450:400c:c00::22b]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XHtta-0007IR-Ae for linux-arm-kernel@lists.infradead.org; Thu, 14 Aug 2014 12:12:43 +0000 Received: by mail-wg0-f43.google.com with SMTP id l18so979413wgh.26 for ; Thu, 14 Aug 2014 05:12:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=2cnB94T8UdAWb3CBiV9aYwTR2YrTZCrAzmP5O97FSqs=; b=ocasxZRVgW0GQ553oqSTk/0Yw3qpGP2n2+gVWvwM0ggBdunObL6/0Y3qiUj0VRBeiE PSy+u4+oQoXHKQo+a8NwgWteam0bj7BMlOXA+JnTqFYXv6b05FHMvcqVzQGMv1gq1hEa bzx3cvrFobfnGvFTXCygvcopT3JIALZx7yrBdTXnTBi31A+h+H3EYQUU6IH5HEf7cvpj 4ISgkgfXnlKzhj5zN95DYFOOFWB/9HAoLZQWdwOdxvacjrGbPFYuf5s8gpr5qcP9Roft LGQc597CZUSkgWggABt/Dg7qX8OmA7tRmBwfFVWklwHeGYxTEG6ScifBrIAWM8ARENYL xX4w== X-Received: by 10.194.187.4 with SMTP id fo4mr11538854wjc.35.1408018340016; Thu, 14 Aug 2014 05:12:20 -0700 (PDT) Received: from cizrna.lan (37-48-38-123.tmcz.cz. [37.48.38.123]) by mx.google.com with ESMTPSA id jx10sm11124810wjc.7.2014.08.14.05.12.18 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Aug 2014 05:12:19 -0700 (PDT) From: Tomeu Vizoso To: Mike Turquette Subject: [PATCH v6 6/6] clk: Add floor and ceiling constraints to clock rates Date: Thu, 14 Aug 2014 14:11:27 +0200 Message-Id: <1408018287-14217-6-git-send-email-tomeu.vizoso@collabora.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1408018287-14217-1-git-send-email-tomeu.vizoso@collabora.com> References: <1408018287-14217-1-git-send-email-tomeu.vizoso@collabora.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140814_051242_611073_73DD9989 X-CRM114-Status: GOOD ( 18.17 ) X-Spam-Score: -0.7 (/) Cc: Tomeu Vizoso , Stephen Warren , Tomasz Figa , linux-kernel@vger.kernel.org, Javier Martinez Canillas , rabin@rab.in, Thierry Reding , Peter De Schrijver , linux-arm-kernel@lists.infradead.org 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: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_NONE,RP_MATCHES_RCVD,T_DKIM_INVALID,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 Adds a way for clock consumers to set maximum and minimum rates. This can be used for thermal drivers to set ceiling rates, or by misc. drivers to set floor rates to assure a minimum performance level. Signed-off-by: Tomeu Vizoso --- v5: * Move the storage of constraints to the per-user clk struct, as suggested by Stephen Warren. --- drivers/clk/clk.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/clk/clk.h | 1 + drivers/clk/clkdev.c | 2 +- include/linux/clk-private.h | 4 ++++ include/linux/clk.h | 18 ++++++++++++++++++ 5 files changed, 60 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index d48e828..32c7831 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -560,6 +560,8 @@ struct clk *__clk_create_clk(struct clk_core *clk_core, const char *dev, clk->dev_id = dev; clk->con_id = con; + hlist_add_head(&clk->child_node, &clk_core->per_user_clks); + return clk; } @@ -1625,6 +1627,7 @@ static void clk_change_rate(struct clk_core *clk) int clk_provider_set_rate(struct clk_core *clk, unsigned long rate) { struct clk_core *top, *fail_clk; + struct clk *clk_user; int ret = 0; if (!clk) @@ -1633,6 +1636,13 @@ int clk_provider_set_rate(struct clk_core *clk, unsigned long rate) /* prevent racing with updates to the clock topology */ clk_prepare_lock(); + hlist_for_each_entry(clk_user, &clk->per_user_clks, child_node) { + rate = max(rate, clk_user->floor_constraint); + + if (clk_user->ceiling_constraint > 0) + rate = min(rate, clk_user->ceiling_constraint); + } + /* bail early if nothing to do */ if (rate == clk_provider_get_rate(clk)) goto out; @@ -1699,6 +1709,24 @@ int clk_set_rate(struct clk *clk_user, unsigned long rate) } EXPORT_SYMBOL_GPL(clk_set_rate); +int clk_set_floor_rate(struct clk *clk_user, unsigned long rate) +{ + struct clk_core *clk = clk_to_clk_core(clk_user); + + clk_user->floor_constraint = rate; + return clk_provider_set_rate(clk, clk_provider_get_rate(clk)); +} +EXPORT_SYMBOL_GPL(clk_set_floor_rate); + +int clk_set_ceiling_rate(struct clk *clk_user, unsigned long rate) +{ + struct clk_core *clk = clk_to_clk_core(clk_user); + + clk_user->ceiling_constraint = rate; + return clk_provider_set_rate(clk, clk_provider_get_rate(clk)); +} +EXPORT_SYMBOL_GPL(clk_set_ceiling_rate); + struct clk_core *clk_provider_get_parent(struct clk_core *clk) { struct clk_core *parent; @@ -2043,6 +2071,8 @@ int __clk_init(struct device *dev, struct clk_core *clk) } } + INIT_HLIST_HEAD(&clk->per_user_clks); + /* * optional platform-specific magic * @@ -2479,6 +2509,12 @@ int clk_notifier_unregister(struct clk *clk_user, struct notifier_block *nb) } EXPORT_SYMBOL_GPL(clk_notifier_unregister); +void __clk_free_clk(struct clk *clk_user) +{ + hlist_del(&clk_user->child_node); + kfree(clk_user); +} + #ifdef CONFIG_OF /** * struct of_clk_provider - Clock provider registration structure diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h index 49eff38..005deb3 100644 --- a/drivers/clk/clk.h +++ b/drivers/clk/clk.h @@ -21,4 +21,5 @@ void of_clk_unlock(void); #if defined(CONFIG_COMMON_CLK) struct clk *__clk_create_clk(struct clk_core *clk_core, const char *dev, const char *con); +void __clk_free_clk(struct clk *clk_user); #endif diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 0752cc9..0db829c 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -270,7 +270,7 @@ void clk_put(struct clk *clk) #if defined(CONFIG_COMMON_CLK) clk_core_t *core = clk_to_clk_core(clk); - kfree(clk); + __clk_free_clk(clk); __clk_put(core); #else __clk_put(clk); diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 9657fc8..c59d000 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -48,6 +48,7 @@ struct clk_core { unsigned long accuracy; struct hlist_head children; struct hlist_node child_node; + struct hlist_head per_user_clks; unsigned int notifier_count; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; @@ -61,6 +62,9 @@ struct clk { const char *dev_id; const char *con_id; void *last_disable; + unsigned long floor_constraint; + unsigned long ceiling_constraint; + struct hlist_node child_node; }; /* diff --git a/include/linux/clk.h b/include/linux/clk.h index f46a2eb..066b100 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -275,6 +275,24 @@ long clk_round_rate(struct clk *clk, unsigned long rate); int clk_set_rate(struct clk *clk, unsigned long rate); /** + * clk_set_floor_rate - set a minimum clock rate for a clock source + * @clk: clock source + * @rate: desired minimum clock rate in Hz + * + * Returns success (0) or negative errno. + */ +int clk_set_floor_rate(struct clk *clk, unsigned long rate); + +/** + * clk_set_ceiling_rate - set a maximum clock rate for a clock source + * @clk: clock source + * @rate: desired maximum clock rate in Hz + * + * Returns success (0) or negative errno. + */ +int clk_set_ceiling_rate(struct clk *clk, unsigned long rate); + +/** * clk_set_parent - set the parent clock source for this clock * @clk: clock source * @parent: parent clock source