| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * OMAP2/3/4 clockdomain framework functions |
| * |
| * Copyright (C) 2008-2011 Texas Instruments, Inc. |
| * Copyright (C) 2008-2011 Nokia Corporation |
| * |
| * Written by Paul Walmsley and Jouni Högander |
| * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com> |
| */ |
| #undef DEBUG |
| |
| #include <linux/kernel.h> |
| #include <linux/device.h> |
| #include <linux/list.h> |
| #include <linux/errno.h> |
| #include <linux/string.h> |
| #include <linux/delay.h> |
| #include <linux/clk.h> |
| #include <linux/limits.h> |
| #include <linux/err.h> |
| #include <linux/clk-provider.h> |
| #include <linux/cpu_pm.h> |
| |
| #include <linux/io.h> |
| |
| #include <linux/bitops.h> |
| |
| #include "soc.h" |
| #include "clock.h" |
| #include "clockdomain.h" |
| #include "pm.h" |
| |
| /* clkdm_list contains all registered struct clockdomains */ |
| static LIST_HEAD(clkdm_list); |
| |
| /* array of clockdomain deps to be added/removed when clkdm in hwsup mode */ |
| static struct clkdm_autodep *autodeps; |
| |
| static struct clkdm_ops *arch_clkdm; |
| void clkdm_save_context(void); |
| void clkdm_restore_context(void); |
| |
| /* Private functions */ |
| |
| static struct clockdomain *_clkdm_lookup(const char *name) |
| { |
| struct clockdomain *clkdm, *temp_clkdm; |
| |
| if (!name) |
| return NULL; |
| |
| clkdm = NULL; |
| |
| list_for_each_entry(temp_clkdm, &clkdm_list, node) { |
| if (!strcmp(name, temp_clkdm->name)) { |
| clkdm = temp_clkdm; |
| break; |
| } |
| } |
| |
| return clkdm; |
| } |
| |
| /** |
| * _clkdm_register - register a clockdomain |
| * @clkdm: struct clockdomain * to register |
| * |
| * Adds a clockdomain to the internal clockdomain list. |
| * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is |
| * already registered by the provided name, or 0 upon success. |
| */ |
| static int _clkdm_register(struct clockdomain *clkdm) |
| { |
| struct powerdomain *pwrdm; |
| |
| if (!clkdm || !clkdm->name) |
| return -EINVAL; |
| |
| pwrdm = pwrdm_lookup(clkdm->pwrdm.name); |
| if (!pwrdm) { |
| pr_err("clockdomain: %s: powerdomain %s does not exist\n", |
| clkdm->name, clkdm->pwrdm.name); |
| return -EINVAL; |
| } |
| clkdm->pwrdm.ptr = pwrdm; |
| |
| /* Verify that the clockdomain is not already registered */ |
| if (_clkdm_lookup(clkdm->name)) |
| return -EEXIST; |
| |
| list_add(&clkdm->node, &clkdm_list); |
| |
| pwrdm_add_clkdm(pwrdm, clkdm); |
| |
| pr_debug("clockdomain: registered %s\n", clkdm->name); |
| |
| return 0; |
| } |
| |
| /* _clkdm_deps_lookup - look up the specified clockdomain in a clkdm list */ |
| static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm, |
| struct clkdm_dep *deps) |
| { |
| struct clkdm_dep *cd; |
| |
| if (!clkdm || !deps) |
| return ERR_PTR(-EINVAL); |
| |
| for (cd = deps; cd->clkdm_name; cd++) { |
| if (!cd->clkdm && cd->clkdm_name) |
| cd->clkdm = _clkdm_lookup(cd->clkdm_name); |
| |
| if (cd->clkdm == clkdm) |
| break; |
| } |
| |
| if (!cd->clkdm_name) |
| return ERR_PTR(-ENOENT); |
| |
| return cd; |
| } |
| |
| /** |
| * _autodep_lookup - resolve autodep clkdm names to clkdm pointers; store |
| * @autodep: struct clkdm_autodep * to resolve |
| * |
| * Resolve autodep clockdomain names to clockdomain pointers via |
| * clkdm_lookup() and store the pointers in the autodep structure. An |
| * "autodep" is a clockdomain sleep/wakeup dependency that is |
| * automatically added and removed whenever clocks in the associated |
| * clockdomain are enabled or disabled (respectively) when the |
| * clockdomain is in hardware-supervised mode. Meant to be called |
| * once at clockdomain layer initialization, since these should remain |
| * fixed for a particular architecture. No return value. |
| * |
| * XXX autodeps are deprecated and should be removed at the earliest |
| * opportunity |
| */ |
| static void _autodep_lookup(struct clkdm_autodep *autodep) |
| { |
| struct clockdomain *clkdm; |
| |
| if (!autodep) |
| return; |
| |
| clkdm = clkdm_lookup(autodep->clkdm.name); |
| if (!clkdm) { |
| pr_err("clockdomain: autodeps: clockdomain %s does not exist\n", |
| autodep->clkdm.name); |
| clkdm = ERR_PTR(-ENOENT); |
| } |
| autodep->clkdm.ptr = clkdm; |
| } |
| |
| /** |
| * _resolve_clkdm_deps() - resolve clkdm_names in @clkdm_deps to clkdms |
| * @clkdm: clockdomain that we are resolving dependencies for |
| * @clkdm_deps: ptr to array of struct clkdm_deps to resolve |
| * |
| * Iterates through @clkdm_deps, looking up the struct clockdomain named by |
| * clkdm_name and storing the clockdomain pointer in the struct clkdm_dep. |
| * No return value. |
| */ |
| static void _resolve_clkdm_deps(struct clockdomain *clkdm, |
| struct clkdm_dep *clkdm_deps) |
| { |
| struct clkdm_dep *cd; |
| |
| for (cd = clkdm_deps; cd && cd->clkdm_name; cd++) { |
| if (cd->clkdm) |
| continue; |
| cd->clkdm = _clkdm_lookup(cd->clkdm_name); |
| |
| WARN(!cd->clkdm, "clockdomain: %s: could not find clkdm %s while resolving dependencies - should never happen", |
| clkdm->name, cd->clkdm_name); |
| } |
| } |
| |
| /** |
| * _clkdm_add_wkdep - add a wakeup dependency from clkdm2 to clkdm1 (lockless) |
| * @clkdm1: wake this struct clockdomain * up (dependent) |
| * @clkdm2: when this struct clockdomain * wakes up (source) |
| * |
| * When the clockdomain represented by @clkdm2 wakes up, wake up |
| * @clkdm1. Implemented in hardware on the OMAP, this feature is |
| * designed to reduce wakeup latency of the dependent clockdomain @clkdm1. |
| * Returns -EINVAL if presented with invalid clockdomain pointers, |
| * -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or 0 upon |
| * success. |
| */ |
| static int _clkdm_add_wkdep(struct clockdomain *clkdm1, |
| struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_add_wkdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of %s when %s wakes up\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| cd->wkdep_usecount++; |
| if (cd->wkdep_usecount == 1) { |
| pr_debug("clockdomain: hardware will wake up %s when %s wakes up\n", |
| clkdm1->name, clkdm2->name); |
| |
| ret = arch_clkdm->clkdm_add_wkdep(clkdm1, clkdm2); |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * _clkdm_del_wkdep - remove a wakeup dep from clkdm2 to clkdm1 (lockless) |
| * @clkdm1: wake this struct clockdomain * up (dependent) |
| * @clkdm2: when this struct clockdomain * wakes up (source) |
| * |
| * Remove a wakeup dependency causing @clkdm1 to wake up when @clkdm2 |
| * wakes up. Returns -EINVAL if presented with invalid clockdomain |
| * pointers, -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or |
| * 0 upon success. |
| */ |
| static int _clkdm_del_wkdep(struct clockdomain *clkdm1, |
| struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_del_wkdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of %s when %s wakes up\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| cd->wkdep_usecount--; |
| if (cd->wkdep_usecount == 0) { |
| pr_debug("clockdomain: hardware will no longer wake up %s after %s wakes up\n", |
| clkdm1->name, clkdm2->name); |
| |
| ret = arch_clkdm->clkdm_del_wkdep(clkdm1, clkdm2); |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * _clkdm_add_sleepdep - add a sleep dependency from clkdm2 to clkdm1 (lockless) |
| * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) |
| * @clkdm2: when this struct clockdomain * is active (source) |
| * |
| * Prevent @clkdm1 from automatically going inactive (and then to |
| * retention or off) if @clkdm2 is active. Returns -EINVAL if |
| * presented with invalid clockdomain pointers or called on a machine |
| * that does not support software-configurable hardware sleep |
| * dependencies, -ENOENT if the specified dependency cannot be set in |
| * hardware, or 0 upon success. |
| */ |
| static int _clkdm_add_sleepdep(struct clockdomain *clkdm1, |
| struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_add_sleepdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep dependency affecting %s from %s\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| cd->sleepdep_usecount++; |
| if (cd->sleepdep_usecount == 1) { |
| pr_debug("clockdomain: will prevent %s from sleeping if %s is active\n", |
| clkdm1->name, clkdm2->name); |
| |
| ret = arch_clkdm->clkdm_add_sleepdep(clkdm1, clkdm2); |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * _clkdm_del_sleepdep - remove a sleep dep from clkdm2 to clkdm1 (lockless) |
| * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) |
| * @clkdm2: when this struct clockdomain * is active (source) |
| * |
| * Allow @clkdm1 to automatically go inactive (and then to retention or |
| * off), independent of the activity state of @clkdm2. Returns -EINVAL |
| * if presented with invalid clockdomain pointers or called on a machine |
| * that does not support software-configurable hardware sleep dependencies, |
| * -ENOENT if the specified dependency cannot be cleared in hardware, or |
| * 0 upon success. |
| */ |
| static int _clkdm_del_sleepdep(struct clockdomain *clkdm1, |
| struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_del_sleepdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep dependency affecting %s from %s\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| cd->sleepdep_usecount--; |
| if (cd->sleepdep_usecount == 0) { |
| pr_debug("clockdomain: will no longer prevent %s from sleeping if %s is active\n", |
| clkdm1->name, clkdm2->name); |
| |
| ret = arch_clkdm->clkdm_del_sleepdep(clkdm1, clkdm2); |
| } |
| |
| return ret; |
| } |
| |
| /* Public functions */ |
| |
| /** |
| * clkdm_register_platform_funcs - register clockdomain implementation fns |
| * @co: func pointers for arch specific implementations |
| * |
| * Register the list of function pointers used to implement the |
| * clockdomain functions on different OMAP SoCs. Should be called |
| * before any other clkdm_register*() function. Returns -EINVAL if |
| * @co is null, -EEXIST if platform functions have already been |
| * registered, or 0 upon success. |
| */ |
| int clkdm_register_platform_funcs(struct clkdm_ops *co) |
| { |
| if (!co) |
| return -EINVAL; |
| |
| if (arch_clkdm) |
| return -EEXIST; |
| |
| arch_clkdm = co; |
| |
| return 0; |
| }; |
| |
| /** |
| * clkdm_register_clkdms - register SoC clockdomains |
| * @cs: pointer to an array of struct clockdomain to register |
| * |
| * Register the clockdomains available on a particular OMAP SoC. Must |
| * be called after clkdm_register_platform_funcs(). May be called |
| * multiple times. Returns -EACCES if called before |
| * clkdm_register_platform_funcs(); -EINVAL if the argument @cs is |
| * null; or 0 upon success. |
| */ |
| int clkdm_register_clkdms(struct clockdomain **cs) |
| { |
| struct clockdomain **c = NULL; |
| |
| if (!arch_clkdm) |
| return -EACCES; |
| |
| if (!cs) |
| return -EINVAL; |
| |
| for (c = cs; *c; c++) |
| _clkdm_register(*c); |
| |
| return 0; |
| } |
| |
| /** |
| * clkdm_register_autodeps - register autodeps (if required) |
| * @ia: pointer to a static array of struct clkdm_autodep to register |
| * |
| * Register clockdomain "automatic dependencies." These are |
| * clockdomain wakeup and sleep dependencies that are automatically |
| * added whenever the first clock inside a clockdomain is enabled, and |
| * removed whenever the last clock inside a clockdomain is disabled. |
| * These are currently only used on OMAP3 devices, and are deprecated, |
| * since they waste energy. However, until the OMAP2/3 IP block |
| * enable/disable sequence can be converted to match the OMAP4 |
| * sequence, they are needed. |
| * |
| * Must be called only after all of the SoC clockdomains are |
| * registered, since the function will resolve autodep clockdomain |
| * names into clockdomain pointers. |
| * |
| * The struct clkdm_autodep @ia array must be static, as this function |
| * does not copy the array elements. |
| * |
| * Returns -EACCES if called before any clockdomains have been |
| * registered, -EINVAL if called with a null @ia argument, -EEXIST if |
| * autodeps have already been registered, or 0 upon success. |
| */ |
| int clkdm_register_autodeps(struct clkdm_autodep *ia) |
| { |
| struct clkdm_autodep *a = NULL; |
| |
| if (list_empty(&clkdm_list)) |
| return -EACCES; |
| |
| if (!ia) |
| return -EINVAL; |
| |
| if (autodeps) |
| return -EEXIST; |
| |
| autodeps = ia; |
| for (a = autodeps; a->clkdm.ptr; a++) |
| _autodep_lookup(a); |
| |
| return 0; |
| } |
| |
| static int cpu_notifier(struct notifier_block *nb, unsigned long cmd, void *v) |
| { |
| switch (cmd) { |
| case CPU_CLUSTER_PM_ENTER: |
| if (enable_off_mode) |
| clkdm_save_context(); |
| break; |
| case CPU_CLUSTER_PM_EXIT: |
| if (enable_off_mode) |
| clkdm_restore_context(); |
| break; |
| } |
| |
| return NOTIFY_OK; |
| } |
| |
| /** |
| * clkdm_complete_init - set up the clockdomain layer |
| * |
| * Put all clockdomains into software-supervised mode; PM code should |
| * later enable hardware-supervised mode as appropriate. Must be |
| * called after clkdm_register_clkdms(). Returns -EACCES if called |
| * before clkdm_register_clkdms(), or 0 upon success. |
| */ |
| int clkdm_complete_init(void) |
| { |
| struct clockdomain *clkdm; |
| static struct notifier_block nb; |
| |
| if (list_empty(&clkdm_list)) |
| return -EACCES; |
| |
| list_for_each_entry(clkdm, &clkdm_list, node) { |
| clkdm_deny_idle(clkdm); |
| |
| _resolve_clkdm_deps(clkdm, clkdm->wkdep_srcs); |
| clkdm_clear_all_wkdeps(clkdm); |
| |
| _resolve_clkdm_deps(clkdm, clkdm->sleepdep_srcs); |
| clkdm_clear_all_sleepdeps(clkdm); |
| } |
| |
| /* Only AM43XX can lose clkdm context during rtc-ddr suspend */ |
| if (soc_is_am43xx()) { |
| nb.notifier_call = cpu_notifier; |
| cpu_pm_register_notifier(&nb); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * clkdm_lookup - look up a clockdomain by name, return a pointer |
| * @name: name of clockdomain |
| * |
| * Find a registered clockdomain by its name @name. Returns a pointer |
| * to the struct clockdomain if found, or NULL otherwise. |
| */ |
| struct clockdomain *clkdm_lookup(const char *name) |
| { |
| struct clockdomain *clkdm, *temp_clkdm; |
| |
| if (!name) |
| return NULL; |
| |
| clkdm = NULL; |
| |
| list_for_each_entry(temp_clkdm, &clkdm_list, node) { |
| if (!strcmp(name, temp_clkdm->name)) { |
| clkdm = temp_clkdm; |
| break; |
| } |
| } |
| |
| return clkdm; |
| } |
| |
| /** |
| * clkdm_for_each - call function on each registered clockdomain |
| * @fn: callback function * |
| * |
| * Call the supplied function @fn for each registered clockdomain. |
| * The callback function @fn can return anything but 0 to bail |
| * out early from the iterator. The callback function is called with |
| * the clkdm_mutex held, so no clockdomain structure manipulation |
| * functions should be called from the callback, although hardware |
| * clockdomain control functions are fine. Returns the last return |
| * value of the callback function, which should be 0 for success or |
| * anything else to indicate failure; or -EINVAL if the function pointer |
| * is null. |
| */ |
| int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user), |
| void *user) |
| { |
| struct clockdomain *clkdm; |
| int ret = 0; |
| |
| if (!fn) |
| return -EINVAL; |
| |
| list_for_each_entry(clkdm, &clkdm_list, node) { |
| ret = (*fn)(clkdm, user); |
| if (ret) |
| break; |
| } |
| |
| return ret; |
| } |
| |
| |
| /** |
| * clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in |
| * @clkdm: struct clockdomain * |
| * |
| * Return a pointer to the struct powerdomain that the specified clockdomain |
| * @clkdm exists in, or returns NULL if @clkdm is NULL. |
| */ |
| struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return NULL; |
| |
| return clkdm->pwrdm.ptr; |
| } |
| |
| |
| /* Hardware clockdomain control */ |
| |
| /** |
| * clkdm_add_wkdep - add a wakeup dependency from clkdm2 to clkdm1 |
| * @clkdm1: wake this struct clockdomain * up (dependent) |
| * @clkdm2: when this struct clockdomain * wakes up (source) |
| * |
| * When the clockdomain represented by @clkdm2 wakes up, wake up |
| * @clkdm1. Implemented in hardware on the OMAP, this feature is |
| * designed to reduce wakeup latency of the dependent clockdomain @clkdm1. |
| * Returns -EINVAL if presented with invalid clockdomain pointers, |
| * -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or 0 upon |
| * success. |
| */ |
| int clkdm_add_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| return PTR_ERR(cd); |
| |
| pwrdm_lock(cd->clkdm->pwrdm.ptr); |
| ret = _clkdm_add_wkdep(clkdm1, clkdm2); |
| pwrdm_unlock(cd->clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_del_wkdep - remove a wakeup dependency from clkdm2 to clkdm1 |
| * @clkdm1: wake this struct clockdomain * up (dependent) |
| * @clkdm2: when this struct clockdomain * wakes up (source) |
| * |
| * Remove a wakeup dependency causing @clkdm1 to wake up when @clkdm2 |
| * wakes up. Returns -EINVAL if presented with invalid clockdomain |
| * pointers, -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or |
| * 0 upon success. |
| */ |
| int clkdm_del_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| return PTR_ERR(cd); |
| |
| pwrdm_lock(cd->clkdm->pwrdm.ptr); |
| ret = _clkdm_del_wkdep(clkdm1, clkdm2); |
| pwrdm_unlock(cd->clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_read_wkdep - read wakeup dependency state from clkdm2 to clkdm1 |
| * @clkdm1: wake this struct clockdomain * up (dependent) |
| * @clkdm2: when this struct clockdomain * wakes up (source) |
| * |
| * Return 1 if a hardware wakeup dependency exists wherein @clkdm1 will be |
| * awoken when @clkdm2 wakes up; 0 if dependency is not set; -EINVAL |
| * if either clockdomain pointer is invalid; or -ENOENT if the hardware |
| * is incapable. |
| * |
| * REVISIT: Currently this function only represents software-controllable |
| * wakeup dependencies. Wakeup dependencies fixed in hardware are not |
| * yet handled here. |
| */ |
| int clkdm_read_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_read_wkdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of %s when %s wakes up\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| /* XXX It's faster to return the wkdep_usecount */ |
| return arch_clkdm->clkdm_read_wkdep(clkdm1, clkdm2); |
| } |
| |
| /** |
| * clkdm_clear_all_wkdeps - remove all wakeup dependencies from target clkdm |
| * @clkdm: struct clockdomain * to remove all wakeup dependencies from |
| * |
| * Remove all inter-clockdomain wakeup dependencies that could cause |
| * @clkdm to wake. Intended to be used during boot to initialize the |
| * PRCM to a known state, after all clockdomains are put into swsup idle |
| * and woken up. Returns -EINVAL if @clkdm pointer is invalid, or |
| * 0 upon success. |
| */ |
| int clkdm_clear_all_wkdeps(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return -EINVAL; |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_clear_all_wkdeps) |
| return -EINVAL; |
| |
| return arch_clkdm->clkdm_clear_all_wkdeps(clkdm); |
| } |
| |
| /** |
| * clkdm_add_sleepdep - add a sleep dependency from clkdm2 to clkdm1 |
| * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) |
| * @clkdm2: when this struct clockdomain * is active (source) |
| * |
| * Prevent @clkdm1 from automatically going inactive (and then to |
| * retention or off) if @clkdm2 is active. Returns -EINVAL if |
| * presented with invalid clockdomain pointers or called on a machine |
| * that does not support software-configurable hardware sleep |
| * dependencies, -ENOENT if the specified dependency cannot be set in |
| * hardware, or 0 upon success. |
| */ |
| int clkdm_add_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| return PTR_ERR(cd); |
| |
| pwrdm_lock(cd->clkdm->pwrdm.ptr); |
| ret = _clkdm_add_sleepdep(clkdm1, clkdm2); |
| pwrdm_unlock(cd->clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_del_sleepdep - remove a sleep dependency from clkdm2 to clkdm1 |
| * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) |
| * @clkdm2: when this struct clockdomain * is active (source) |
| * |
| * Allow @clkdm1 to automatically go inactive (and then to retention or |
| * off), independent of the activity state of @clkdm2. Returns -EINVAL |
| * if presented with invalid clockdomain pointers or called on a machine |
| * that does not support software-configurable hardware sleep dependencies, |
| * -ENOENT if the specified dependency cannot be cleared in hardware, or |
| * 0 upon success. |
| */ |
| int clkdm_del_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) |
| return PTR_ERR(cd); |
| |
| pwrdm_lock(cd->clkdm->pwrdm.ptr); |
| ret = _clkdm_del_sleepdep(clkdm1, clkdm2); |
| pwrdm_unlock(cd->clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_read_sleepdep - read sleep dependency state from clkdm2 to clkdm1 |
| * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) |
| * @clkdm2: when this struct clockdomain * is active (source) |
| * |
| * Return 1 if a hardware sleep dependency exists wherein @clkdm1 will |
| * not be allowed to automatically go inactive if @clkdm2 is active; |
| * 0 if @clkdm1's automatic power state inactivity transition is independent |
| * of @clkdm2's; -EINVAL if either clockdomain pointer is invalid or called |
| * on a machine that does not support software-configurable hardware sleep |
| * dependencies; or -ENOENT if the hardware is incapable. |
| * |
| * REVISIT: Currently this function only represents software-controllable |
| * sleep dependencies. Sleep dependencies fixed in hardware are not |
| * yet handled here. |
| */ |
| int clkdm_read_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) |
| { |
| struct clkdm_dep *cd; |
| int ret = 0; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) |
| ret = PTR_ERR(cd); |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_read_sleepdep) |
| ret = -EINVAL; |
| |
| if (ret) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep dependency affecting %s from %s\n", |
| clkdm1->name, clkdm2->name); |
| return ret; |
| } |
| |
| /* XXX It's faster to return the sleepdep_usecount */ |
| return arch_clkdm->clkdm_read_sleepdep(clkdm1, clkdm2); |
| } |
| |
| /** |
| * clkdm_clear_all_sleepdeps - remove all sleep dependencies from target clkdm |
| * @clkdm: struct clockdomain * to remove all sleep dependencies from |
| * |
| * Remove all inter-clockdomain sleep dependencies that could prevent |
| * @clkdm from idling. Intended to be used during boot to initialize the |
| * PRCM to a known state, after all clockdomains are put into swsup idle |
| * and woken up. Returns -EINVAL if @clkdm pointer is invalid, or |
| * 0 upon success. |
| */ |
| int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return -EINVAL; |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_clear_all_sleepdeps) |
| return -EINVAL; |
| |
| return arch_clkdm->clkdm_clear_all_sleepdeps(clkdm); |
| } |
| |
| /** |
| * clkdm_sleep_nolock - force clockdomain sleep transition (lockless) |
| * @clkdm: struct clockdomain * |
| * |
| * Instruct the CM to force a sleep transition on the specified |
| * clockdomain @clkdm. Only for use by the powerdomain code. Returns |
| * -EINVAL if @clkdm is NULL or if clockdomain does not support |
| * software-initiated sleep; 0 upon success. |
| */ |
| int clkdm_sleep_nolock(struct clockdomain *clkdm) |
| { |
| int ret; |
| |
| if (!clkdm) |
| return -EINVAL; |
| |
| if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) { |
| pr_debug("clockdomain: %s does not support forcing sleep via software\n", |
| clkdm->name); |
| return -EINVAL; |
| } |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_sleep) |
| return -EINVAL; |
| |
| pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name); |
| |
| clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; |
| ret = arch_clkdm->clkdm_sleep(clkdm); |
| ret |= pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_sleep - force clockdomain sleep transition |
| * @clkdm: struct clockdomain * |
| * |
| * Instruct the CM to force a sleep transition on the specified |
| * clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if |
| * clockdomain does not support software-initiated sleep; 0 upon |
| * success. |
| */ |
| int clkdm_sleep(struct clockdomain *clkdm) |
| { |
| int ret; |
| |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| ret = clkdm_sleep_nolock(clkdm); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_wakeup_nolock - force clockdomain wakeup transition (lockless) |
| * @clkdm: struct clockdomain * |
| * |
| * Instruct the CM to force a wakeup transition on the specified |
| * clockdomain @clkdm. Only for use by the powerdomain code. Returns |
| * -EINVAL if @clkdm is NULL or if the clockdomain does not support |
| * software-controlled wakeup; 0 upon success. |
| */ |
| int clkdm_wakeup_nolock(struct clockdomain *clkdm) |
| { |
| int ret; |
| |
| if (!clkdm) |
| return -EINVAL; |
| |
| if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) { |
| pr_debug("clockdomain: %s does not support forcing wakeup via software\n", |
| clkdm->name); |
| return -EINVAL; |
| } |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_wakeup) |
| return -EINVAL; |
| |
| pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name); |
| |
| clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; |
| ret = arch_clkdm->clkdm_wakeup(clkdm); |
| ret |= pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_wakeup - force clockdomain wakeup transition |
| * @clkdm: struct clockdomain * |
| * |
| * Instruct the CM to force a wakeup transition on the specified |
| * clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if the |
| * clockdomain does not support software-controlled wakeup; 0 upon |
| * success. |
| */ |
| int clkdm_wakeup(struct clockdomain *clkdm) |
| { |
| int ret; |
| |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| ret = clkdm_wakeup_nolock(clkdm); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_allow_idle_nolock - enable hwsup idle transitions for clkdm |
| * @clkdm: struct clockdomain * |
| * |
| * Allow the hardware to automatically switch the clockdomain @clkdm |
| * into active or idle states, as needed by downstream clocks. If the |
| * clockdomain has any downstream clocks enabled in the clock |
| * framework, wkdep/sleepdep autodependencies are added; this is so |
| * device drivers can read and write to the device. Only for use by |
| * the powerdomain code. No return value. |
| */ |
| void clkdm_allow_idle_nolock(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return; |
| |
| if (!WARN_ON(!clkdm->forcewake_count)) |
| clkdm->forcewake_count--; |
| |
| if (clkdm->forcewake_count) |
| return; |
| |
| if (!clkdm->usecount && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) |
| clkdm_sleep_nolock(clkdm); |
| |
| if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) |
| return; |
| |
| if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING) |
| return; |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_allow_idle) |
| return; |
| |
| pr_debug("clockdomain: enabling automatic idle transitions for %s\n", |
| clkdm->name); |
| |
| clkdm->_flags |= _CLKDM_FLAG_HWSUP_ENABLED; |
| arch_clkdm->clkdm_allow_idle(clkdm); |
| pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| } |
| |
| /** |
| * clkdm_allow_idle - enable hwsup idle transitions for clkdm |
| * @clkdm: struct clockdomain * |
| * |
| * Allow the hardware to automatically switch the clockdomain @clkdm into |
| * active or idle states, as needed by downstream clocks. If the |
| * clockdomain has any downstream clocks enabled in the clock |
| * framework, wkdep/sleepdep autodependencies are added; this is so |
| * device drivers can read and write to the device. No return value. |
| */ |
| void clkdm_allow_idle(struct clockdomain *clkdm) |
| { |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| clkdm_allow_idle_nolock(clkdm); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| } |
| |
| /** |
| * clkdm_deny_idle - disable hwsup idle transitions for clkdm |
| * @clkdm: struct clockdomain * |
| * |
| * Prevent the hardware from automatically switching the clockdomain |
| * @clkdm into inactive or idle states. If the clockdomain has |
| * downstream clocks enabled in the clock framework, wkdep/sleepdep |
| * autodependencies are removed. Only for use by the powerdomain |
| * code. No return value. |
| */ |
| void clkdm_deny_idle_nolock(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return; |
| |
| if (clkdm->forcewake_count++) |
| return; |
| |
| if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) |
| clkdm_wakeup_nolock(clkdm); |
| |
| if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) |
| return; |
| |
| if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING) |
| return; |
| |
| if (!arch_clkdm || !arch_clkdm->clkdm_deny_idle) |
| return; |
| |
| pr_debug("clockdomain: disabling automatic idle transitions for %s\n", |
| clkdm->name); |
| |
| clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; |
| arch_clkdm->clkdm_deny_idle(clkdm); |
| pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| } |
| |
| /** |
| * clkdm_deny_idle - disable hwsup idle transitions for clkdm |
| * @clkdm: struct clockdomain * |
| * |
| * Prevent the hardware from automatically switching the clockdomain |
| * @clkdm into inactive or idle states. If the clockdomain has |
| * downstream clocks enabled in the clock framework, wkdep/sleepdep |
| * autodependencies are removed. No return value. |
| */ |
| void clkdm_deny_idle(struct clockdomain *clkdm) |
| { |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| clkdm_deny_idle_nolock(clkdm); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| } |
| |
| /** |
| * clkdm_in_hwsup - is clockdomain @clkdm have hardware-supervised idle enabled? |
| * @clkdm: struct clockdomain * |
| * |
| * Returns true if clockdomain @clkdm currently has |
| * hardware-supervised idle enabled, or false if it does not or if |
| * @clkdm is NULL. It is only valid to call this function after |
| * clkdm_init() has been called. This function does not actually read |
| * bits from the hardware; it instead tests an in-memory flag that is |
| * changed whenever the clockdomain code changes the auto-idle mode. |
| */ |
| bool clkdm_in_hwsup(struct clockdomain *clkdm) |
| { |
| bool ret; |
| |
| if (!clkdm) |
| return false; |
| |
| ret = (clkdm->_flags & _CLKDM_FLAG_HWSUP_ENABLED) ? true : false; |
| |
| return ret; |
| } |
| |
| /** |
| * clkdm_missing_idle_reporting - can @clkdm enter autoidle even if in use? |
| * @clkdm: struct clockdomain * |
| * |
| * Returns true if clockdomain @clkdm has the |
| * CLKDM_MISSING_IDLE_REPORTING flag set, or false if not or @clkdm is |
| * null. More information is available in the documentation for the |
| * CLKDM_MISSING_IDLE_REPORTING macro. |
| */ |
| bool clkdm_missing_idle_reporting(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return false; |
| |
| return (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING) ? true : false; |
| } |
| |
| /* Public autodep handling functions (deprecated) */ |
| |
| /** |
| * clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable |
| * @clkdm: struct clockdomain * |
| * |
| * Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm' |
| * in hardware-supervised mode. Meant to be called from clock framework |
| * when a clock inside clockdomain 'clkdm' is enabled. No return value. |
| * |
| * XXX autodeps are deprecated and should be removed at the earliest |
| * opportunity |
| */ |
| void clkdm_add_autodeps(struct clockdomain *clkdm) |
| { |
| struct clkdm_autodep *autodep; |
| |
| if (!autodeps || clkdm->flags & CLKDM_NO_AUTODEPS) |
| return; |
| |
| for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { |
| if (IS_ERR(autodep->clkdm.ptr)) |
| continue; |
| |
| pr_debug("clockdomain: %s: adding %s sleepdep/wkdep\n", |
| clkdm->name, autodep->clkdm.ptr->name); |
| |
| _clkdm_add_sleepdep(clkdm, autodep->clkdm.ptr); |
| _clkdm_add_wkdep(clkdm, autodep->clkdm.ptr); |
| } |
| } |
| |
| /** |
| * clkdm_del_autodeps - remove auto sleepdeps/wkdeps from clkdm |
| * @clkdm: struct clockdomain * |
| * |
| * Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm' |
| * in hardware-supervised mode. Meant to be called from clock framework |
| * when a clock inside clockdomain 'clkdm' is disabled. No return value. |
| * |
| * XXX autodeps are deprecated and should be removed at the earliest |
| * opportunity |
| */ |
| void clkdm_del_autodeps(struct clockdomain *clkdm) |
| { |
| struct clkdm_autodep *autodep; |
| |
| if (!autodeps || clkdm->flags & CLKDM_NO_AUTODEPS) |
| return; |
| |
| for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { |
| if (IS_ERR(autodep->clkdm.ptr)) |
| continue; |
| |
| pr_debug("clockdomain: %s: removing %s sleepdep/wkdep\n", |
| clkdm->name, autodep->clkdm.ptr->name); |
| |
| _clkdm_del_sleepdep(clkdm, autodep->clkdm.ptr); |
| _clkdm_del_wkdep(clkdm, autodep->clkdm.ptr); |
| } |
| } |
| |
| /* Clockdomain-to-clock/hwmod framework interface code */ |
| |
| static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm) |
| { |
| if (!clkdm || !arch_clkdm || !arch_clkdm->clkdm_clk_enable) |
| return -EINVAL; |
| |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| |
| /* |
| * For arch's with no autodeps, clkcm_clk_enable |
| * should be called for every clock instance or hwmod that is |
| * enabled, so the clkdm can be force woken up. |
| */ |
| clkdm->usecount++; |
| if (clkdm->usecount > 1 && autodeps) { |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| return 0; |
| } |
| |
| arch_clkdm->clkdm_clk_enable(clkdm); |
| pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| |
| pr_debug("clockdomain: %s: enabled\n", clkdm->name); |
| |
| return 0; |
| } |
| |
| /** |
| * clkdm_clk_enable - add an enabled downstream clock to this clkdm |
| * @clkdm: struct clockdomain * |
| * @clk: struct clk * of the enabled downstream clock |
| * |
| * Increment the usecount of the clockdomain @clkdm and ensure that it |
| * is awake before @clk is enabled. Intended to be called by |
| * clk_enable() code. If the clockdomain is in software-supervised |
| * idle mode, force the clockdomain to wake. If the clockdomain is in |
| * hardware-supervised idle mode, add clkdm-pwrdm autodependencies, to |
| * ensure that devices in the clockdomain can be read from/written to |
| * by on-chip processors. Returns -EINVAL if passed null pointers; |
| * returns 0 upon success or if the clockdomain is in hwsup idle mode. |
| */ |
| int clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk) |
| { |
| /* |
| * XXX Rewrite this code to maintain a list of enabled |
| * downstream clocks for debugging purposes? |
| */ |
| |
| if (!clk) |
| return -EINVAL; |
| |
| return _clkdm_clk_hwmod_enable(clkdm); |
| } |
| |
| /** |
| * clkdm_clk_disable - remove an enabled downstream clock from this clkdm |
| * @clkdm: struct clockdomain * |
| * @clk: struct clk * of the disabled downstream clock |
| * |
| * Decrement the usecount of this clockdomain @clkdm when @clk is |
| * disabled. Intended to be called by clk_disable() code. If the |
| * clockdomain usecount goes to 0, put the clockdomain to sleep |
| * (software-supervised mode) or remove the clkdm autodependencies |
| * (hardware-supervised mode). Returns -EINVAL if passed null |
| * pointers; -ERANGE if the @clkdm usecount underflows; or returns 0 |
| * upon success or if the clockdomain is in hwsup idle mode. |
| */ |
| int clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk) |
| { |
| if (!clkdm || !clk || !arch_clkdm || !arch_clkdm->clkdm_clk_disable) |
| return -EINVAL; |
| |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| |
| /* corner case: disabling unused clocks */ |
| if ((__clk_get_enable_count(clk) == 0) && clkdm->usecount == 0) |
| goto ccd_exit; |
| |
| if (clkdm->usecount == 0) { |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| WARN_ON(1); /* underflow */ |
| return -ERANGE; |
| } |
| |
| clkdm->usecount--; |
| if (clkdm->usecount > 0) { |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| return 0; |
| } |
| |
| arch_clkdm->clkdm_clk_disable(clkdm); |
| pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| |
| pr_debug("clockdomain: %s: disabled\n", clkdm->name); |
| |
| ccd_exit: |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| |
| return 0; |
| } |
| |
| /** |
| * clkdm_hwmod_enable - add an enabled downstream hwmod to this clkdm |
| * @clkdm: struct clockdomain * |
| * @oh: struct omap_hwmod * of the enabled downstream hwmod |
| * |
| * Increment the usecount of the clockdomain @clkdm and ensure that it |
| * is awake before @oh is enabled. Intended to be called by |
| * module_enable() code. |
| * If the clockdomain is in software-supervised idle mode, force the |
| * clockdomain to wake. If the clockdomain is in hardware-supervised idle |
| * mode, add clkdm-pwrdm autodependencies, to ensure that devices in the |
| * clockdomain can be read from/written to by on-chip processors. |
| * Returns -EINVAL if passed null pointers; |
| * returns 0 upon success or if the clockdomain is in hwsup idle mode. |
| */ |
| int clkdm_hwmod_enable(struct clockdomain *clkdm, struct omap_hwmod *oh) |
| { |
| /* The clkdm attribute does not exist yet prior OMAP4 */ |
| if (cpu_is_omap24xx() || cpu_is_omap34xx()) |
| return 0; |
| |
| /* |
| * XXX Rewrite this code to maintain a list of enabled |
| * downstream hwmods for debugging purposes? |
| */ |
| |
| if (!oh) |
| return -EINVAL; |
| |
| return _clkdm_clk_hwmod_enable(clkdm); |
| } |
| |
| /** |
| * clkdm_hwmod_disable - remove an enabled downstream hwmod from this clkdm |
| * @clkdm: struct clockdomain * |
| * @oh: struct omap_hwmod * of the disabled downstream hwmod |
| * |
| * Decrement the usecount of this clockdomain @clkdm when @oh is |
| * disabled. Intended to be called by module_disable() code. |
| * If the clockdomain usecount goes to 0, put the clockdomain to sleep |
| * (software-supervised mode) or remove the clkdm autodependencies |
| * (hardware-supervised mode). |
| * Returns -EINVAL if passed null pointers; -ERANGE if the @clkdm usecount |
| * underflows; or returns 0 upon success or if the clockdomain is in hwsup |
| * idle mode. |
| */ |
| int clkdm_hwmod_disable(struct clockdomain *clkdm, struct omap_hwmod *oh) |
| { |
| /* The clkdm attribute does not exist yet prior OMAP4 */ |
| if (cpu_is_omap24xx() || cpu_is_omap34xx()) |
| return 0; |
| |
| /* |
| * XXX Rewrite this code to maintain a list of enabled |
| * downstream hwmods for debugging purposes? |
| */ |
| |
| if (!clkdm || !oh || !arch_clkdm || !arch_clkdm->clkdm_clk_disable) |
| return -EINVAL; |
| |
| pwrdm_lock(clkdm->pwrdm.ptr); |
| |
| if (clkdm->usecount == 0) { |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| WARN_ON(1); /* underflow */ |
| return -ERANGE; |
| } |
| |
| clkdm->usecount--; |
| if (clkdm->usecount > 0) { |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| return 0; |
| } |
| |
| arch_clkdm->clkdm_clk_disable(clkdm); |
| pwrdm_state_switch_nolock(clkdm->pwrdm.ptr); |
| pwrdm_unlock(clkdm->pwrdm.ptr); |
| |
| pr_debug("clockdomain: %s: disabled\n", clkdm->name); |
| |
| return 0; |
| } |
| |
| /** |
| * _clkdm_save_context - save the context for the control of this clkdm |
| * |
| * Due to a suspend or hibernation operation, the state of the registers |
| * controlling this clkdm will be lost, save their context. |
| */ |
| static int _clkdm_save_context(struct clockdomain *clkdm, void *ununsed) |
| { |
| if (!arch_clkdm || !arch_clkdm->clkdm_save_context) |
| return -EINVAL; |
| |
| return arch_clkdm->clkdm_save_context(clkdm); |
| } |
| |
| /** |
| * _clkdm_restore_context - restore context for control of this clkdm |
| * |
| * Restore the register values for this clockdomain. |
| */ |
| static int _clkdm_restore_context(struct clockdomain *clkdm, void *ununsed) |
| { |
| if (!arch_clkdm || !arch_clkdm->clkdm_restore_context) |
| return -EINVAL; |
| |
| return arch_clkdm->clkdm_restore_context(clkdm); |
| } |
| |
| /** |
| * clkdm_save_context - Saves the context for each registered clkdm |
| * |
| * Save the context for each registered clockdomain. |
| */ |
| void clkdm_save_context(void) |
| { |
| clkdm_for_each(_clkdm_save_context, NULL); |
| } |
| |
| /** |
| * clkdm_restore_context - Restores the context for each registered clkdm |
| * |
| * Restore the context for each registered clockdomain. |
| */ |
| void clkdm_restore_context(void) |
| { |
| clkdm_for_each(_clkdm_restore_context, NULL); |
| } |