From patchwork Tue Jan 5 22:54:58 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Walmsley X-Patchwork-Id: 71205 X-Patchwork-Delegate: paul@pwsan.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.2) with ESMTP id o05Mx1sT007638 for ; Tue, 5 Jan 2010 22:59:02 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754812Ab0AEW6u (ORCPT ); Tue, 5 Jan 2010 17:58:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932190Ab0AEW6u (ORCPT ); Tue, 5 Jan 2010 17:58:50 -0500 Received: from utopia.booyaka.com ([72.9.107.138]:49855 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754622Ab0AEW6X (ORCPT ); Tue, 5 Jan 2010 17:58:23 -0500 Received: (qmail 14249 invoked by uid 526); 5 Jan 2010 22:58:22 -0000 MBOX-Line: From nobody Tue Jan 5 15:54:58 2010 Subject: [PATCH 05/10] OMAP clockdomains: add usecounting for wakeup and sleep dependencies To: linux-omap@vger.kernel.org From: Paul Walmsley Date: Tue, 05 Jan 2010 15:54:58 -0700 Message-ID: <20100105225453.16474.92006.stgit@localhost.localdomain> In-Reply-To: <20100105225217.16474.44114.stgit@localhost.localdomain> References: <20100105225217.16474.44114.stgit@localhost.localdomain> User-Agent: StGit/0.15-22-gda30 MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c index 2af9996..d039df7 100644 --- a/arch/arm/mach-omap2/clockdomain.c +++ b/arch/arm/mach-omap2/clockdomain.c @@ -113,7 +113,6 @@ static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm, return ERR_PTR(-EINVAL); for (cd = deps; cd->clkdm_name; cd++) { - if (!omap_chip_is(cd->omap_chip)) continue; @@ -122,7 +121,6 @@ static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm, if (cd->clkdm == clkdm) break; - } if (!cd->clkdm_name) @@ -254,6 +252,96 @@ static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable) } +/** + * _init_wkdep_usecount - initialize wkdep usecounts to match hardware + * @clkdm: clockdomain to initialize wkdep usecounts + * + * Initialize the wakeup dependency usecount variables for clockdomain @clkdm. + * If a wakeup dependency is present in the hardware, the usecount will be + * set to 1; otherwise, it will be set to 0. Software should clear all + * software wakeup dependencies prior to calling this function if it wishes + * to ensure that all usecounts start at 0. No return value. + */ +static void _init_wkdep_usecount(struct clockdomain *clkdm) +{ + u32 v; + struct clkdm_dep *cd; + + if (!clkdm->wkdep_srcs) + return; + + for (cd = clkdm->wkdep_srcs; cd->clkdm_name; cd++) { + if (!omap_chip_is(cd->omap_chip)) + continue; + + if (!cd->clkdm && cd->clkdm_name) + cd->clkdm = _clkdm_lookup(cd->clkdm_name); + + if (!cd->clkdm) { + WARN(!cd->clkdm, "clockdomain: %s: wkdep clkdm %s not " + "found\n", clkdm->name, cd->clkdm_name); + continue; + } + + v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs, + PM_WKDEP, + (1 << cd->clkdm->dep_bit)); + + if (v) + pr_debug("clockdomain: %s: wakeup dependency already " + "set to wake up when %s wakes\n", + clkdm->name, cd->clkdm->name); + + atomic_set(&cd->wkdep_usecount, (v) ? 1 : 0); + } +} + +/** + * _init_sleepdep_usecount - initialize sleepdep usecounts to match hardware + * @clkdm: clockdomain to initialize sleepdep usecounts + * + * Initialize the sleep dependency usecount variables for clockdomain @clkdm. + * If a sleep dependency is present in the hardware, the usecount will be + * set to 1; otherwise, it will be set to 0. Software should clear all + * software sleep dependencies prior to calling this function if it wishes + * to ensure that all usecounts start at 0. No return value. + */ +static void _init_sleepdep_usecount(struct clockdomain *clkdm) +{ + u32 v; + struct clkdm_dep *cd; + + if (!cpu_is_omap34xx()) + return; + + if (!clkdm->sleepdep_srcs) + return; + + for (cd = clkdm->sleepdep_srcs; cd->clkdm_name; cd++) { + if (!omap_chip_is(cd->omap_chip)) + continue; + + if (!cd->clkdm && cd->clkdm_name) + cd->clkdm = _clkdm_lookup(cd->clkdm_name); + + if (!cd->clkdm) { + WARN(!cd->clkdm, "clockdomain: %s: sleepdep clkdm %s " + "not found\n", clkdm->name, cd->clkdm_name); + continue; + } + + v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs, + OMAP3430_CM_SLEEPDEP, + (1 << cd->clkdm->dep_bit)); + + if (v) + pr_debug("clockdomain: %s: sleep dependency already " + "set to prevent from idling until %s " + "idles\n", clkdm->name, cd->clkdm->name); + + atomic_set(&cd->sleepdep_usecount, (v) ? 1 : 0); + } +}; /* Public functions */ @@ -272,6 +360,7 @@ void clkdm_init(struct clockdomain **clkdms, struct clkdm_autodep *init_autodeps) { struct clockdomain **c = NULL; + struct clockdomain *clkdm; struct clkdm_autodep *autodep = NULL; if (clkdms) @@ -282,6 +371,15 @@ void clkdm_init(struct clockdomain **clkdms, if (autodeps) for (autodep = autodeps; autodep->clkdm.ptr; autodep++) _autodep_lookup(autodep); + + /* + * Ensure that the *dep_usecount registers reflect the current + * state of the PRCM. + */ + list_for_each_entry(clkdm, &clkdm_list, node) { + _init_wkdep_usecount(clkdm); + _init_sleepdep_usecount(clkdm); + } } /** @@ -387,11 +485,13 @@ int clkdm_add_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } - pr_debug("clockdomain: hardware will wake up %s when %s wakes up\n", - clkdm1->name, clkdm2->name); + if (atomic_inc_return(&cd->wkdep_usecount) == 1) { + pr_debug("clockdomain: hardware will wake up %s when %s wakes " + "up\n", clkdm1->name, clkdm2->name); - prm_set_mod_reg_bits((1 << clkdm2->dep_bit), - clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); + prm_set_mod_reg_bits((1 << clkdm2->dep_bit), + clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); + } return 0; } @@ -420,11 +520,13 @@ int clkdm_del_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } - pr_debug("clockdomain: hardware will no longer wake up %s after %s " - "wakes up\n", clkdm1->name, clkdm2->name); + if (atomic_dec_return(&cd->wkdep_usecount) == 0) { + pr_debug("clockdomain: hardware will no longer wake up %s " + "after %s wakes up\n", clkdm1->name, clkdm2->name); - prm_clear_mod_reg_bits((1 << clkdm2->dep_bit), - clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); + prm_clear_mod_reg_bits((1 << clkdm2->dep_bit), + clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); + } return 0; } @@ -457,6 +559,7 @@ int clkdm_read_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } + /* XXX It's faster to return the atomic wkdep_usecount */ return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP, (1 << clkdm2->dep_bit)); } @@ -491,12 +594,14 @@ int clkdm_add_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } - pr_debug("clockdomain: will prevent %s from sleeping if %s is active\n", - clkdm1->name, clkdm2->name); + if (atomic_inc_return(&cd->sleepdep_usecount) == 1) { + pr_debug("clockdomain: will prevent %s from sleeping if %s " + "is active\n", clkdm1->name, clkdm2->name); - cm_set_mod_reg_bits((1 << clkdm2->dep_bit), - clkdm1->pwrdm.ptr->prcm_offs, - OMAP3430_CM_SLEEPDEP); + cm_set_mod_reg_bits((1 << clkdm2->dep_bit), + clkdm1->pwrdm.ptr->prcm_offs, + OMAP3430_CM_SLEEPDEP); + } return 0; } @@ -531,12 +636,15 @@ int clkdm_del_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } - pr_debug("clockdomain: will no longer prevent %s from sleeping if " - "%s is active\n", clkdm1->name, clkdm2->name); + if (atomic_dec_return(&cd->sleepdep_usecount) == 0) { + pr_debug("clockdomain: will no longer prevent %s from " + "sleeping if %s is active\n", clkdm1->name, + clkdm2->name); - cm_clear_mod_reg_bits((1 << clkdm2->dep_bit), - clkdm1->pwrdm.ptr->prcm_offs, - OMAP3430_CM_SLEEPDEP); + cm_clear_mod_reg_bits((1 << clkdm2->dep_bit), + clkdm1->pwrdm.ptr->prcm_offs, + OMAP3430_CM_SLEEPDEP); + } return 0; } @@ -575,12 +683,12 @@ int clkdm_read_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) return PTR_ERR(cd); } + /* XXX It's faster to return the atomic sleepdep_usecount */ return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, OMAP3430_CM_SLEEPDEP, (1 << clkdm2->dep_bit)); } - /** * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode * @clk: struct clk * of a clockdomain diff --git a/arch/arm/plat-omap/include/plat/clockdomain.h b/arch/arm/plat-omap/include/plat/clockdomain.h index 2286971..192cc95 100644 --- a/arch/arm/plat-omap/include/plat/clockdomain.h +++ b/arch/arm/plat-omap/include/plat/clockdomain.h @@ -70,6 +70,12 @@ struct clkdm_dep { /* Clockdomain pointer - resolved by the clockdomain code */ struct clockdomain *clkdm; + /* Number of wakeup dependencies causing this clkdm to wake */ + atomic_t wkdep_usecount; + + /* Number of sleep dependencies that could prevent clkdm from idle */ + atomic_t sleepdep_usecount; + /* Flags to mark OMAP chip restrictions, etc. */ const struct omap_chip_id omap_chip;