From patchwork Mon Aug 31 10:18:01 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sekhar Nori X-Patchwork-Id: 44846 Received: from comal.ext.ti.com (comal.ext.ti.com [198.47.26.152]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7VAJoiS019143 for ; Mon, 31 Aug 2009 10:19:50 GMT Received: from dlep34.itg.ti.com ([157.170.170.115]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id n7VAIJsY014898; Mon, 31 Aug 2009 05:18:24 -0500 Received: from linux.omap.com (localhost [127.0.0.1]) by dlep34.itg.ti.com (8.13.7/8.13.7) with ESMTP id n7VAIIng015685; Mon, 31 Aug 2009 05:18:18 -0500 (CDT) Received: from linux.omap.com (localhost [127.0.0.1]) by linux.omap.com (Postfix) with ESMTP id B53F480630; Mon, 31 Aug 2009 05:18:16 -0500 (CDT) X-Original-To: davinci-linux-open-source@linux.davincidsp.com Delivered-To: davinci-linux-open-source@linux.davincidsp.com Received: from dbdp31.itg.ti.com (dbdp31.itg.ti.com [172.24.170.98]) by linux.omap.com (Postfix) with ESMTP id DCCCF8062A for ; Mon, 31 Aug 2009 05:18:10 -0500 (CDT) Received: from psplinux051.india.ti.com (localhost [127.0.0.1]) by dbdp31.itg.ti.com (8.13.8/8.13.8) with ESMTP id n7VAI8u5001140; Mon, 31 Aug 2009 15:48:08 +0530 (IST) Received: from psplinux051.india.ti.com (localhost [127.0.0.1]) by psplinux051.india.ti.com (8.13.1/8.13.1) with ESMTP id n7VAI8EH002987; Mon, 31 Aug 2009 15:48:08 +0530 Received: (from a0875516@localhost) by psplinux051.india.ti.com (8.13.1/8.13.1/Submit) id n7VAI8sK002984; Mon, 31 Aug 2009 15:48:08 +0530 From: Sekhar Nori To: davinci-linux-open-source@linux.davincidsp.com Date: Mon, 31 Aug 2009 15:48:01 +0530 Message-Id: <1251713887-2824-4-git-send-email-nsekhar@ti.com> X-Mailer: git-send-email 1.6.2.4 In-Reply-To: <1251713887-2824-3-git-send-email-nsekhar@ti.com> References: <1251713887-2824-1-git-send-email-nsekhar@ti.com> <1251713887-2824-2-git-send-email-nsekhar@ti.com> <1251713887-2824-3-git-send-email-nsekhar@ti.com> Cc: Subject: [PATCH v4 04/10] davinci: enable easy top down traversal of clock tree X-BeenThere: davinci-linux-open-source@linux.davincidsp.com X-Mailman-Version: 2.1.4 Precedence: list List-Id: davinci-linux-open-source.linux.davincidsp.com List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: davinci-linux-open-source-bounces@linux.davincidsp.com Errors-To: davinci-linux-open-source-bounces@linux.davincidsp.com Achieve easy top down traversal of clock tree by keeping track of each clock's list of children. This is useful in supporting DVFS where clock rates of all children need to be updated in an efficient manner. Signed-off-by: Sekhar Nori --- arch/arm/mach-davinci/clock.c | 10 +++++++--- arch/arm/mach-davinci/clock.h | 2 ++ 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c index 83d54d5..f8c4ef0 100644 --- a/arch/arm/mach-davinci/clock.c +++ b/arch/arm/mach-davinci/clock.c @@ -123,8 +123,12 @@ int clk_register(struct clk *clk) clk->name, clk->parent->name)) return -EINVAL; + INIT_LIST_HEAD(&clk->children); + mutex_lock(&clocks_mutex); list_add_tail(&clk->node, &clocks); + if (clk->parent) + list_add_tail(&clk->childnode, &clk->parent->children); mutex_unlock(&clocks_mutex); /* If rate is already set, use it */ @@ -146,6 +150,7 @@ void clk_unregister(struct clk *clk) mutex_lock(&clocks_mutex); list_del(&clk->node); + list_del(&clk->childnode); mutex_unlock(&clocks_mutex); } EXPORT_SYMBOL(clk_unregister); @@ -352,9 +357,8 @@ dump_clock(struct seq_file *s, unsigned nest, struct clk *parent) /* REVISIT show device associations too */ /* cost is now small, but not linear... */ - list_for_each_entry(clk, &clocks, node) { - if (clk->parent == parent) - dump_clock(s, nest + NEST_DELTA, clk); + list_for_each_entry(clk, &parent->children, childnode) { + dump_clock(s, nest + NEST_DELTA, clk); } } diff --git a/arch/arm/mach-davinci/clock.h b/arch/arm/mach-davinci/clock.h index 27233cb..f88794d 100644 --- a/arch/arm/mach-davinci/clock.h +++ b/arch/arm/mach-davinci/clock.h @@ -69,6 +69,8 @@ struct clk { u8 lpsc; u8 psc_ctlr; struct clk *parent; + struct list_head children; /* list of children */ + struct list_head childnode; /* parent's child list node */ struct pll_data *pll_data; u32 div_reg; };