From patchwork Fri May 23 05:08:10 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun Kumar K X-Patchwork-Id: 4228101 Return-Path: X-Original-To: patchwork-linux-samsung-soc@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 B83C59F32B for ; Fri, 23 May 2014 05:08:29 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C2BE220295 for ; Fri, 23 May 2014 05:08:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 826A0201E4 for ; Fri, 23 May 2014 05:08:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751424AbaEWFI0 (ORCPT ); Fri, 23 May 2014 01:08:26 -0400 Received: from mail-pb0-f47.google.com ([209.85.160.47]:62565 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750961AbaEWFIZ (ORCPT ); Fri, 23 May 2014 01:08:25 -0400 Received: by mail-pb0-f47.google.com with SMTP id rp16so3595944pbb.20 for ; Thu, 22 May 2014 22:08:25 -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=YqRcrD8maQLweqH079fJcBnf1WPB4brCIiGdlJ6l9Fs=; b=GW+x9NqJy7xjXw1BvqIhFrQ5+5m3da8lDHF5T0yA7zd7oqbth+8eXXISIBscjNmGs/ 3dwa58obBdKnNLgtcy8uVT8iLDVvoKlXI+nTLRKdHN+CbPepF+rANVdtQOrh3jDJNruB hQs8WB9ZHGMM6hriHc5D8WHDixv8duo4fi2wstlF2H0RjGT8BBVOFzb4JJ91F3GBxWAa wYcnjyy1VX2mRosJT9bYOCLTdHwLqrCEbwU11v481q9x79ny1tqvMaO9Clm1klhu3yMr 1YuhHALMCm82Br/Y+Bo8llzLSfzGuifMqguBDacTaib+6rq2kTyBtxstLtFEdJFKVmyK 8pKQ== X-Received: by 10.68.219.162 with SMTP id pp2mr2697001pbc.47.1400821705260; Thu, 22 May 2014 22:08:25 -0700 (PDT) Received: from localhost.localdomain ([14.140.216.146]) by mx.google.com with ESMTPSA id bu1sm2399974pbb.54.2014.05.22.22.08.21 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 22 May 2014 22:08:24 -0700 (PDT) From: Arun Kumar K To: linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org Cc: t.figa@samsung.com, kgene.kim@samsung.com, mark.rutland@arm.com, pawel.moll@arm.com, swarren@wwwdotorg.org, prathyush.k@samsung.com, abrestic@chromium.org, arunkk.samsung@gmail.com Subject: [PATCH 1/3] ARM: EXYNOS: Add support for clock handling in power domain Date: Fri, 23 May 2014 10:38:10 +0530 Message-Id: <1400821692-22370-2-git-send-email-arun.kk@samsung.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1400821692-22370-1-git-send-email-arun.kk@samsung.com> References: <1400821692-22370-1-git-send-email-arun.kk@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=ham 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: Prathyush K While powering on/off a local powerdomain in exynos5 chipsets, the input clocks to each device gets modified. This behaviour is based on the SYSCLK_SYS_PWR_REG registers. E.g. SYSCLK_MFC_SYS_PWR_REG = 0x0, the parent of input clock to MFC (aclk333) gets modified to oscclk = 0x1, no change in clocks. The recommended value of SYSCLK_SYS_PWR_REG before power gating any domain is 0x0. So we must also restore the clocks while powering on a domain everytime. This patch adds the framework for getting the required mux and parent clocks through a power domain device node. With this patch, while powering off a domain, parent is set to oscclk and while powering back on, its re-set to the correct parent which is as per the recommended pd on/off sequence. Signed-off-by: Prathyush K Signed-off-by: Andrew Bresticker Signed-off-by: Arun Kumar K --- .../bindings/arm/exynos/power_domain.txt | 18 +++++++ arch/arm/mach-exynos/pm_domains.c | 56 +++++++++++++++++++- 2 files changed, 73 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt index 5216b41..168a191 100644 --- a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt +++ b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt @@ -9,6 +9,16 @@ Required Properties: - reg: physical base address of the controller and length of memory mapped region. +Optional Properties: +- clocks: List of clock handles. The parent clocks of the input clocks to the + devices in this power domain are set to oscclk before power gating and + restored back after powering on a domain. This is required for all domains + which are powered on and off and not required for unused domains. + The following clocks can be specified: + - oscclk: oscillator clock. + - clk(n): input clock to the devices in this power domain + - pclk(n): parent clock of input clock to the devices in this power domain + Node of a device using power domains must have a samsung,power-domain property defined with a phandle to respective power domain. @@ -19,6 +29,14 @@ Example: reg = <0x10023C00 0x10>; }; + mfc_pd: power-domain@10044060 { + compatible = "samsung,exynos4210-pd"; + reg = <0x10044060 0x20>; + clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>, + <&clock CLK_MOUT_USER_ACLK333>; + clock-names = "oscclk", "pclk0", "clk0"; + }; + Example of the node using power domain: node { diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c index fe6570e..e5fe76d 100644 --- a/arch/arm/mach-exynos/pm_domains.c +++ b/arch/arm/mach-exynos/pm_domains.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -24,6 +25,8 @@ #include "regs-pmu.h" +#define MAX_CLK_PER_DOMAIN 4 + /* * Exynos specific wrapper around the generic power domain */ @@ -32,6 +35,9 @@ struct exynos_pm_domain { char const *name; bool is_off; struct generic_pm_domain pd; + struct clk *oscclk; + struct clk *clk[MAX_CLK_PER_DOMAIN]; + struct clk *pclk[MAX_CLK_PER_DOMAIN]; }; static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) @@ -44,6 +50,18 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) pd = container_of(domain, struct exynos_pm_domain, pd); base = pd->base; + /* Set oscclk before powering off a domain*/ + if (!power_on) { + int i; + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + if (!pd->clk[i]) + break; + if (clk_set_parent(pd->clk[i], pd->oscclk)) + pr_info("%s: error setting oscclk as parent to clock %d\n", + pd->name, i); + } + } + pwr = power_on ? S5P_INT_LOCAL_PWR_EN : 0; __raw_writel(pwr, base); @@ -60,6 +78,19 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) cpu_relax(); usleep_range(80, 100); } + + /* Restore clocks after powering on a domain*/ + if (power_on) { + int i; + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + if (!pd->clk[i]) + break; + if (clk_set_parent(pd->clk[i], pd->pclk[i])) + pr_info("%s: error setting parent to clock%d\n", + pd->name, i); + } + } + return 0; } @@ -152,9 +183,11 @@ static __init int exynos4_pm_init_power_domain(void) for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") { struct exynos_pm_domain *pd; - int on; + int on, i; + struct device *dev; pdev = of_find_device_by_node(np); + dev = &pdev->dev; pd = kzalloc(sizeof(*pd), GFP_KERNEL); if (!pd) { @@ -170,6 +203,27 @@ static __init int exynos4_pm_init_power_domain(void) pd->pd.power_on = exynos_pd_power_on; pd->pd.of_node = np; + pd->oscclk = devm_clk_get(dev, "oscclk"); + if (IS_ERR(pd->oscclk)) + goto no_clk; + + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + struct clk *tmp, *tmp_parent; + char clk_name[8]; + + snprintf(clk_name, sizeof(clk_name), "clk%d", i); + tmp = devm_clk_get(dev, clk_name); + if (IS_ERR(tmp)) + break; + snprintf(clk_name, sizeof(clk_name), "pclk%d", i); + tmp_parent = devm_clk_get(dev, clk_name); + if (IS_ERR(tmp_parent)) + break; + pd->clk[i] = tmp; + pd->pclk[i] = tmp_parent; + } + +no_clk: platform_set_drvdata(pdev, pd); on = __raw_readl(pd->base + 0x4) & S5P_INT_LOCAL_PWR_EN;