| /* |
| * OMAP2/3/4 clockdomain framework functions |
| * |
| * Copyright (C) 2008-2010 Texas Instruments, Inc. |
| * Copyright (C) 2008-2010 Nokia Corporation |
| * |
| * Written by Paul Walmsley and Jouni Högander |
| * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #undef DEBUG |
| |
| #include <linux/kernel.h> |
| #include <linux/device.h> |
| #include <linux/list.h> |
| #include <linux/errno.h> |
| #include <linux/delay.h> |
| #include <linux/clk.h> |
| #include <linux/limits.h> |
| #include <linux/err.h> |
| |
| #include <linux/io.h> |
| |
| #include <linux/bitops.h> |
| |
| #include "prm2xxx_3xxx.h" |
| #include "prm-regbits-24xx.h" |
| #include "cm2xxx_3xxx.h" |
| |
| #include <plat/clock.h> |
| #include <plat/powerdomain.h> |
| #include <plat/clockdomain.h> |
| #include <plat/prcm.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; |
| |
| |
| /* 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; |
| |
| if (!omap_chip_is(clkdm->omap_chip)) |
| 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 || !omap_chip_is(clkdm->omap_chip)) |
| return ERR_PTR(-EINVAL); |
| |
| for (cd = deps; 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 == 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; |
| |
| if (!omap_chip_is(autodep->omap_chip)) |
| 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; |
| } |
| |
| /* |
| * _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 |
| */ |
| static void _clkdm_add_autodeps(struct clockdomain *clkdm) |
| { |
| struct clkdm_autodep *autodep; |
| |
| if (!autodeps) |
| return; |
| |
| for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { |
| if (IS_ERR(autodep->clkdm.ptr)) |
| continue; |
| |
| if (!omap_chip_is(autodep->omap_chip)) |
| continue; |
| |
| pr_debug("clockdomain: adding %s sleepdep/wkdep for " |
| "clkdm %s\n", autodep->clkdm.ptr->name, |
| clkdm->name); |
| |
| clkdm_add_sleepdep(clkdm, autodep->clkdm.ptr); |
| clkdm_add_wkdep(clkdm, autodep->clkdm.ptr); |
| } |
| } |
| |
| /* |
| * _clkdm_add_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 |
| */ |
| static void _clkdm_del_autodeps(struct clockdomain *clkdm) |
| { |
| struct clkdm_autodep *autodep; |
| |
| if (!autodeps) |
| return; |
| |
| for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { |
| if (IS_ERR(autodep->clkdm.ptr)) |
| continue; |
| |
| if (!omap_chip_is(autodep->omap_chip)) |
| continue; |
| |
| pr_debug("clockdomain: removing %s sleepdep/wkdep for " |
| "clkdm %s\n", autodep->clkdm.ptr->name, |
| clkdm->name); |
| |
| clkdm_del_sleepdep(clkdm, autodep->clkdm.ptr); |
| clkdm_del_wkdep(clkdm, autodep->clkdm.ptr); |
| } |
| } |
| |
| /** |
| * _enable_hwsup - place a clockdomain into hardware-supervised idle |
| * @clkdm: struct clockdomain * |
| * |
| * Place the clockdomain into hardware-supervised idle mode. No return |
| * value. |
| * |
| * XXX Should this return an error if the clockdomain does not support |
| * hardware-supervised idle mode? |
| */ |
| static void _enable_hwsup(struct clockdomain *clkdm) |
| { |
| u32 bits, v; |
| |
| if (cpu_is_omap24xx()) |
| bits = OMAP24XX_CLKSTCTRL_ENABLE_AUTO; |
| else if (cpu_is_omap34xx() || cpu_is_omap44xx()) |
| bits = OMAP34XX_CLKSTCTRL_ENABLE_AUTO; |
| else |
| BUG(); |
| |
| bits = bits << __ffs(clkdm->clktrctrl_mask); |
| |
| v = __raw_readl(clkdm->clkstctrl_reg); |
| v &= ~(clkdm->clktrctrl_mask); |
| v |= bits; |
| __raw_writel(v, clkdm->clkstctrl_reg); |
| |
| } |
| |
| /** |
| * _disable_hwsup - place a clockdomain into software-supervised idle |
| * @clkdm: struct clockdomain * |
| * |
| * Place the clockdomain @clkdm into software-supervised idle mode. |
| * No return value. |
| * |
| * XXX Should this return an error if the clockdomain does not support |
| * software-supervised idle mode? |
| */ |
| static void _disable_hwsup(struct clockdomain *clkdm) |
| { |
| u32 bits, v; |
| |
| if (cpu_is_omap24xx()) { |
| bits = OMAP24XX_CLKSTCTRL_DISABLE_AUTO; |
| } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { |
| bits = OMAP34XX_CLKSTCTRL_DISABLE_AUTO; |
| } else { |
| BUG(); |
| } |
| |
| bits = bits << __ffs(clkdm->clktrctrl_mask); |
| |
| v = __raw_readl(clkdm->clkstctrl_reg); |
| v &= ~(clkdm->clktrctrl_mask); |
| v |= bits; |
| __raw_writel(v, clkdm->clkstctrl_reg); |
| |
| } |
| |
| /* Public functions */ |
| |
| /** |
| * clkdm_init - set up the clockdomain layer |
| * @clkdms: optional pointer to an array of clockdomains to register |
| * @init_autodeps: optional pointer to an array of autodeps to register |
| * |
| * Set up internal state. If a pointer to an array of clockdomains |
| * @clkdms was supplied, loop through the list of clockdomains, |
| * register all that are available on the current platform. Similarly, |
| * if a pointer to an array of clockdomain autodependencies |
| * @init_autodeps was provided, register those. No return value. |
| */ |
| 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) |
| for (c = clkdms; *c; c++) |
| _clkdm_register(*c); |
| |
| autodeps = init_autodeps; |
| if (autodeps) |
| for (autodep = autodeps; autodep->clkdm.ptr; autodep++) |
| _autodep_lookup(autodep); |
| |
| /* |
| * Put all clockdomains into software-supervised mode; PM code |
| * should later enable hardware-supervised mode as appropriate |
| */ |
| list_for_each_entry(clkdm, &clkdm_list, node) { |
| if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) |
| omap2_clkdm_wakeup(clkdm); |
| else if (clkdm->flags & CLKDM_CAN_DISABLE_AUTO) |
| omap2_clkdm_deny_idle(clkdm); |
| |
| clkdm_clear_all_wkdeps(clkdm); |
| clkdm_clear_all_sleepdeps(clkdm); |
| } |
| } |
| |
| /** |
| * 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; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of " |
| "%s when %s wakes up\n", clkdm1->name, clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| 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); |
| |
| omap2_prm_set_mod_reg_bits((1 << clkdm2->dep_bit), |
| clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of " |
| "%s when %s wakes up\n", clkdm1->name, clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| 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); |
| |
| omap2_prm_clear_mod_reg_bits((1 << clkdm2->dep_bit), |
| clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear wake up of " |
| "%s when %s wakes up\n", clkdm1->name, clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| /* XXX It's faster to return the atomic wkdep_usecount */ |
| return omap2_prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP, |
| (1 << clkdm2->dep_bit)); |
| } |
| |
| /** |
| * 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) |
| { |
| struct clkdm_dep *cd; |
| u32 mask = 0; |
| |
| if (!clkdm) |
| return -EINVAL; |
| |
| for (cd = clkdm->wkdep_srcs; cd && 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); |
| |
| /* PRM accesses are slow, so minimize them */ |
| mask |= 1 << cd->clkdm->dep_bit; |
| atomic_set(&cd->wkdep_usecount, 0); |
| } |
| |
| omap2_prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs, PM_WKDEP); |
| |
| return 0; |
| } |
| |
| /** |
| * 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; |
| |
| if (!cpu_is_omap34xx()) |
| return -EINVAL; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep " |
| "dependency affecting %s from %s\n", clkdm1->name, |
| clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| 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); |
| |
| omap2_cm_set_mod_reg_bits((1 << clkdm2->dep_bit), |
| clkdm1->pwrdm.ptr->prcm_offs, |
| OMAP3430_CM_SLEEPDEP); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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; |
| |
| if (!cpu_is_omap34xx()) |
| return -EINVAL; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep " |
| "dependency affecting %s from %s\n", clkdm1->name, |
| clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| 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); |
| |
| omap2_cm_clear_mod_reg_bits((1 << clkdm2->dep_bit), |
| clkdm1->pwrdm.ptr->prcm_offs, |
| OMAP3430_CM_SLEEPDEP); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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; |
| |
| if (!cpu_is_omap34xx()) |
| return -EINVAL; |
| |
| if (!clkdm1 || !clkdm2) |
| return -EINVAL; |
| |
| cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); |
| if (IS_ERR(cd)) { |
| pr_debug("clockdomain: hardware cannot set/clear sleep " |
| "dependency affecting %s from %s\n", clkdm1->name, |
| clkdm2->name); |
| return PTR_ERR(cd); |
| } |
| |
| /* XXX It's faster to return the atomic sleepdep_usecount */ |
| return omap2_prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, |
| OMAP3430_CM_SLEEPDEP, |
| (1 << clkdm2->dep_bit)); |
| } |
| |
| /** |
| * 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) |
| { |
| struct clkdm_dep *cd; |
| u32 mask = 0; |
| |
| if (!cpu_is_omap34xx()) |
| return -EINVAL; |
| |
| if (!clkdm) |
| return -EINVAL; |
| |
| for (cd = clkdm->sleepdep_srcs; cd && 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); |
| |
| /* PRM accesses are slow, so minimize them */ |
| mask |= 1 << cd->clkdm->dep_bit; |
| atomic_set(&cd->sleepdep_usecount, 0); |
| } |
| |
| omap2_prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs, |
| OMAP3430_CM_SLEEPDEP); |
| |
| return 0; |
| } |
| |
| /** |
| * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode |
| * @clkdm: struct clkdm * of a clockdomain |
| * |
| * Return the clockdomain @clkdm current state transition mode from the |
| * corresponding domain CM_CLKSTCTRL register. Returns -EINVAL if @clkdm |
| * is NULL or the current mode upon success. |
| */ |
| static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm) |
| { |
| u32 v; |
| |
| if (!clkdm) |
| return -EINVAL; |
| |
| v = __raw_readl(clkdm->clkstctrl_reg); |
| v &= clkdm->clktrctrl_mask; |
| v >>= __ffs(clkdm->clktrctrl_mask); |
| |
| return v; |
| } |
| |
| /** |
| * omap2_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 omap2_clkdm_sleep(struct clockdomain *clkdm) |
| { |
| 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; |
| } |
| |
| pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name); |
| |
| if (cpu_is_omap24xx()) { |
| |
| omap2_cm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK, |
| clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL); |
| |
| } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { |
| |
| u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP << |
| __ffs(clkdm->clktrctrl_mask)); |
| |
| u32 v = __raw_readl(clkdm->clkstctrl_reg); |
| v &= ~(clkdm->clktrctrl_mask); |
| v |= bits; |
| __raw_writel(v, clkdm->clkstctrl_reg); |
| |
| } else { |
| BUG(); |
| }; |
| |
| return 0; |
| } |
| |
| /** |
| * omap2_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 omap2_clkdm_wakeup(struct clockdomain *clkdm) |
| { |
| 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; |
| } |
| |
| pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name); |
| |
| if (cpu_is_omap24xx()) { |
| |
| omap2_cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK, |
| clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL); |
| |
| } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { |
| |
| u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP << |
| __ffs(clkdm->clktrctrl_mask)); |
| |
| u32 v = __raw_readl(clkdm->clkstctrl_reg); |
| v &= ~(clkdm->clktrctrl_mask); |
| v |= bits; |
| __raw_writel(v, clkdm->clkstctrl_reg); |
| |
| } else { |
| BUG(); |
| }; |
| |
| return 0; |
| } |
| |
| /** |
| * omap2_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 omap2_clkdm_allow_idle(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return; |
| |
| if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) { |
| pr_debug("clock: automatic idle transitions cannot be enabled " |
| "on clockdomain %s\n", clkdm->name); |
| return; |
| } |
| |
| pr_debug("clockdomain: enabling automatic idle transitions for %s\n", |
| clkdm->name); |
| |
| /* |
| * XXX This should be removed once TI adds wakeup/sleep |
| * dependency code and data for OMAP4. |
| */ |
| if (cpu_is_omap44xx()) { |
| WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency " |
| "support is not yet implemented\n"); |
| } else { |
| if (atomic_read(&clkdm->usecount) > 0) |
| _clkdm_add_autodeps(clkdm); |
| } |
| |
| _enable_hwsup(clkdm); |
| |
| pwrdm_clkdm_state_switch(clkdm); |
| } |
| |
| /** |
| * omap2_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 omap2_clkdm_deny_idle(struct clockdomain *clkdm) |
| { |
| if (!clkdm) |
| return; |
| |
| if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) { |
| pr_debug("clockdomain: automatic idle transitions cannot be " |
| "disabled on %s\n", clkdm->name); |
| return; |
| } |
| |
| pr_debug("clockdomain: disabling automatic idle transitions for %s\n", |
| clkdm->name); |
| |
| _disable_hwsup(clkdm); |
| |
| /* |
| * XXX This should be removed once TI adds wakeup/sleep |
| * dependency code and data for OMAP4. |
| */ |
| if (cpu_is_omap44xx()) { |
| WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency " |
| "support is not yet implemented\n"); |
| } else { |
| if (atomic_read(&clkdm->usecount) > 0) |
| _clkdm_del_autodeps(clkdm); |
| } |
| } |
| |
| |
| /* Clockdomain-to-clock framework interface code */ |
| |
| /** |
| * omap2_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 omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk) |
| { |
| int v; |
| |
| /* |
| * XXX Rewrite this code to maintain a list of enabled |
| * downstream clocks for debugging purposes? |
| */ |
| |
| if (!clkdm || !clk) |
| return -EINVAL; |
| |
| if (atomic_inc_return(&clkdm->usecount) > 1) |
| return 0; |
| |
| /* Clockdomain now has one enabled downstream clock */ |
| |
| pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name, |
| clk->name); |
| |
| if (!clkdm->clkstctrl_reg) |
| return 0; |
| |
| v = omap2_clkdm_clktrctrl_read(clkdm); |
| |
| if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || |
| (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) { |
| /* Disable HW transitions when we are changing deps */ |
| _disable_hwsup(clkdm); |
| _clkdm_add_autodeps(clkdm); |
| _enable_hwsup(clkdm); |
| } else { |
| omap2_clkdm_wakeup(clkdm); |
| } |
| |
| pwrdm_wait_transition(clkdm->pwrdm.ptr); |
| pwrdm_clkdm_state_switch(clkdm); |
| |
| return 0; |
| } |
| |
| /** |
| * omap2_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 and debugging |
| * is enabled; or returns 0 upon success or if the clockdomain is in |
| * hwsup idle mode. |
| */ |
| int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk) |
| { |
| int v; |
| |
| /* |
| * XXX Rewrite this code to maintain a list of enabled |
| * downstream clocks for debugging purposes? |
| */ |
| |
| if (!clkdm || !clk) |
| return -EINVAL; |
| |
| #ifdef DEBUG |
| if (atomic_read(&clkdm->usecount) == 0) { |
| WARN_ON(1); /* underflow */ |
| return -ERANGE; |
| } |
| #endif |
| |
| if (atomic_dec_return(&clkdm->usecount) > 0) |
| return 0; |
| |
| /* All downstream clocks of this clockdomain are now disabled */ |
| |
| pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name, |
| clk->name); |
| |
| if (!clkdm->clkstctrl_reg) |
| return 0; |
| |
| v = omap2_clkdm_clktrctrl_read(clkdm); |
| |
| if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || |
| (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) { |
| /* Disable HW transitions when we are changing deps */ |
| _disable_hwsup(clkdm); |
| _clkdm_del_autodeps(clkdm); |
| _enable_hwsup(clkdm); |
| } else { |
| omap2_clkdm_sleep(clkdm); |
| } |
| |
| pwrdm_clkdm_state_switch(clkdm); |
| |
| return 0; |
| } |
| |