diff options
Diffstat (limited to 'arch/arm/mach-tegra/clock.c')
| -rw-r--r-- | arch/arm/mach-tegra/clock.c | 709 |
1 files changed, 709 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c new file mode 100644 index 000000000000..ae19f95585be --- /dev/null +++ b/arch/arm/mach-tegra/clock.c @@ -0,0 +1,709 @@ +/* + * + * Copyright (C) 2010 Google, Inc. + * + * Author: + * Colin Cross <ccross@google.com> + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/list.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/debugfs.h> +#include <linux/slab.h> +#include <linux/seq_file.h> +#include <linux/regulator/consumer.h> +#include <asm/clkdev.h> + +#include "clock.h" +#include "board.h" +#include "fuse.h" + +static LIST_HEAD(clocks); + +static DEFINE_SPINLOCK(clock_lock); +static DEFINE_MUTEX(dvfs_lock); + +static int clk_is_dvfs(struct clk *c) +{ + return (c->dvfs != NULL); +}; + +static int dvfs_set_rate(struct dvfs *d, unsigned long rate) +{ + struct dvfs_table *t; + + if (d->table == NULL) + return -ENODEV; + + for (t = d->table; t->rate != 0; t++) { + if (rate <= t->rate) { + if (!d->reg) + return 0; + + return regulator_set_voltage(d->reg, + t->millivolts * 1000, + d->max_millivolts * 1000); + } + } + + return -EINVAL; +} + +static void dvfs_init(struct clk *c) +{ + int process_id; + int i; + struct dvfs_table *table; + + process_id = c->dvfs->cpu ? tegra_core_process_id() : + tegra_cpu_process_id(); + + for (i = 0; i < c->dvfs->process_id_table_length; i++) + if (process_id == c->dvfs->process_id_table[i].process_id) + c->dvfs->table = c->dvfs->process_id_table[i].table; + + if (c->dvfs->table == NULL) { + pr_err("Failed to find dvfs table for clock %s process %d\n", + c->name, process_id); + return; + } + + c->dvfs->max_millivolts = 0; + for (table = c->dvfs->table; table->rate != 0; table++) + if (c->dvfs->max_millivolts < table->millivolts) + c->dvfs->max_millivolts = table->millivolts; + + c->dvfs->reg = regulator_get(NULL, c->dvfs->reg_id); + + if (IS_ERR(c->dvfs->reg)) { + pr_err("Failed to get regulator %s for clock %s\n", + c->dvfs->reg_id, c->name); + c->dvfs->reg = NULL; + return; + } + + if (c->refcnt > 0) + dvfs_set_rate(c->dvfs, c->rate); +} + +struct clk *tegra_get_clock_by_name(const char *name) +{ + struct clk *c; + struct clk *ret = NULL; + unsigned long flags; + spin_lock_irqsave(&clock_lock, flags); + list_for_each_entry(c, &clocks, node) { + if (strcmp(c->name, name) == 0) { + ret = c; + break; + } + } + spin_unlock_irqrestore(&clock_lock, flags); + return ret; +} + +static void clk_recalculate_rate(struct clk *c) +{ + u64 rate; + + if (!c->parent) + return; + + rate = c->parent->rate; + + if (c->mul != 0 && c->div != 0) { + rate = rate * c->mul; + do_div(rate, c->div); + } + + if (rate > c->max_rate) + pr_warn("clocks: Set clock %s to rate %llu, max is %lu\n", + c->name, rate, c->max_rate); + + c->rate = rate; +} + +int clk_reparent(struct clk *c, struct clk *parent) +{ + pr_debug("%s: %s\n", __func__, c->name); + c->parent = parent; + list_del(&c->sibling); + list_add_tail(&c->sibling, &parent->children); + return 0; +} + +static void propagate_rate(struct clk *c) +{ + struct clk *clkp; + pr_debug("%s: %s\n", __func__, c->name); + list_for_each_entry(clkp, &c->children, sibling) { + pr_debug(" %s\n", clkp->name); + clk_recalculate_rate(clkp); + propagate_rate(clkp); + } +} + +void clk_init(struct clk *c) +{ + unsigned long flags; + + pr_debug("%s: %s\n", __func__, c->name); + + spin_lock_irqsave(&clock_lock, flags); + + INIT_LIST_HEAD(&c->children); + INIT_LIST_HEAD(&c->sibling); + + if (c->ops && c->ops->init) + c->ops->init(c); + + clk_recalculate_rate(c); + + list_add(&c->node, &clocks); + + if (c->parent) + list_add_tail(&c->sibling, &c->parent->children); + + spin_unlock_irqrestore(&clock_lock, flags); +} + +int clk_enable_locked(struct clk *c) +{ + int ret; + pr_debug("%s: %s\n", __func__, c->name); + if (c->refcnt == 0) { + if (c->parent) { + ret = clk_enable_locked(c->parent); + if (ret) + return ret; + } + + if (c->ops && c->ops->enable) { + ret = c->ops->enable(c); + if (ret) { + if (c->parent) + clk_disable_locked(c->parent); + return ret; + } + c->state = ON; +#ifdef CONFIG_DEBUG_FS + c->set = 1; +#endif + } + } + c->refcnt++; + + return 0; +} + +int clk_enable_cansleep(struct clk *c) +{ + int ret; + unsigned long flags; + + mutex_lock(&dvfs_lock); + + if (clk_is_dvfs(c) && c->refcnt > 0) + dvfs_set_rate(c->dvfs, c->rate); + + spin_lock_irqsave(&clock_lock, flags); + ret = clk_enable_locked(c); + spin_unlock_irqrestore(&clock_lock, flags); + + mutex_unlock(&dvfs_lock); + + return ret; +} +EXPORT_SYMBOL(clk_enable_cansleep); + +int clk_enable(struct clk *c) +{ + int ret; + unsigned long flags; + + if (clk_is_dvfs(c)) + BUG(); + + spin_lock_irqsave(&clock_lock, flags); + ret = clk_enable_locked(c); + spin_unlock_irqrestore(&clock_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_enable); + +void clk_disable_locked(struct clk *c) +{ + pr_debug("%s: %s\n", __func__, c->name); + if (c->refcnt == 0) { + WARN(1, "Attempting to disable clock %s with refcnt 0", c->name); + return; + } + if (c->refcnt == 1) { + if (c->ops && c->ops->disable) + c->ops->disable(c); + + if (c->parent) + clk_disable_locked(c->parent); + + c->state = OFF; + } + c->refcnt--; +} + +void clk_disable_cansleep(struct clk *c) +{ + unsigned long flags; + + mutex_lock(&dvfs_lock); + + spin_lock_irqsave(&clock_lock, flags); + clk_disable_locked(c); + spin_unlock_irqrestore(&clock_lock, flags); + + if (clk_is_dvfs(c) && c->refcnt == 0) + dvfs_set_rate(c->dvfs, c->rate); + + mutex_unlock(&dvfs_lock); +} +EXPORT_SYMBOL(clk_disable_cansleep); + +void clk_disable(struct clk *c) +{ + unsigned long flags; + + if (clk_is_dvfs(c)) + BUG(); + + spin_lock_irqsave(&clock_lock, flags); + clk_disable_locked(c); + spin_unlock_irqrestore(&clock_lock, flags); +} +EXPORT_SYMBOL(clk_disable); + +int clk_set_parent_locked(struct clk *c, struct clk *parent) +{ + int ret; + + pr_debug("%s: %s\n", __func__, c->name); + + if (!c->ops || !c->ops->set_parent) + return -ENOSYS; + + ret = c->ops->set_parent(c, parent); + + if (ret) + return ret; + + clk_recalculate_rate(c); + + propagate_rate(c); + + return 0; +} + +int clk_set_parent(struct clk *c, struct clk *parent) +{ + int ret; + unsigned long flags; + spin_lock_irqsave(&clock_lock, flags); + ret = clk_set_parent_locked(c, parent); + spin_unlock_irqrestore(&clock_lock, flags); + return ret; +} +EXPORT_SYMBOL(clk_set_parent); + +struct clk *clk_get_parent(struct clk *c) +{ + return c->parent; +} +EXPORT_SYMBOL(clk_get_parent); + +int clk_set_rate_locked(struct clk *c, unsigned long rate) +{ + int ret; + + if (rate > c->max_rate) + rate = c->max_rate; + + if (!c->ops || !c->ops->set_rate) + return -ENOSYS; + + ret = c->ops->set_rate(c, rate); + + if (ret) + return ret; + + clk_recalculate_rate(c); + + propagate_rate(c); + + return 0; +} + +int clk_set_rate_cansleep(struct clk *c, unsigned long rate) +{ + int ret = 0; + unsigned long flags; + + pr_debug("%s: %s\n", __func__, c->name); + + mutex_lock(&dvfs_lock); + + if (rate > c->rate) + ret = dvfs_set_rate(c->dvfs, rate); + if (ret) + goto out; + + spin_lock_irqsave(&clock_lock, flags); + ret = clk_set_rate_locked(c, rate); + spin_unlock_irqrestore(&clock_lock, flags); + + if (ret) + goto out; + + ret = dvfs_set_rate(c->dvfs, rate); + +out: + mutex_unlock(&dvfs_lock); + return ret; +} +EXPORT_SYMBOL(clk_set_rate_cansleep); + +int clk_set_rate(struct clk *c, unsigned long rate) +{ + int ret = 0; + unsigned long flags; + + pr_debug("%s: %s\n", __func__, c->name); + + if (clk_is_dvfs(c)) + BUG(); + + spin_lock_irqsave(&clock_lock, flags); + ret = clk_set_rate_locked(c, rate); + spin_unlock_irqrestore(&clock_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_set_rate); + +unsigned long clk_get_rate(struct clk *c) +{ + unsigned long flags; + unsigned long ret; + + spin_lock_irqsave(&clock_lock, flags); + + pr_debug("%s: %s\n", __func__, c->name); + + ret = c->rate; + + spin_unlock_irqrestore(&clock_lock, flags); + return ret; +} +EXPORT_SYMBOL(clk_get_rate); + +long clk_round_rate(struct clk *c, unsigned long rate) +{ + pr_debug("%s: %s\n", __func__, c->name); + + if (!c->ops || !c->ops->round_rate) + return -ENOSYS; + + if (rate > c->max_rate) + rate = c->max_rate; + + return c->ops->round_rate(c, rate); +} +EXPORT_SYMBOL(clk_round_rate); + +static int tegra_clk_init_one_from_table(struct tegra_clk_init_table *table) +{ + struct clk *c; + struct clk *p; + + int ret = 0; + + c = tegra_get_clock_by_name(table->name); + + if (!c) { + pr_warning("Unable to initialize clock %s\n", + table->name); + return -ENODEV; + } + + if (table->parent) { + p = tegra_get_clock_by_name(table->parent); + if (!p) { + pr_warning("Unable to find parent %s of clock %s\n", + table->parent, table->name); + return -ENODEV; + } + + if (c->parent != p) { + ret = clk_set_parent(c, p); + if (ret) { + pr_warning("Unable to set parent %s of clock %s: %d\n", + table->parent, table->name, ret); + return -EINVAL; + } + } + } + + if (table->rate && table->rate != clk_get_rate(c)) { + ret = clk_set_rate(c, table->rate); + if (ret) { + pr_warning("Unable to set clock %s to rate %lu: %d\n", + table->name, table->rate, ret); + return -EINVAL; + } + } + + if (table->enabled) { + ret = clk_enable(c); + if (ret) { + pr_warning("Unable to enable clock %s: %d\n", + table->name, ret); + return -EINVAL; + } + } + + return 0; +} + +void tegra_clk_init_from_table(struct tegra_clk_init_table *table) +{ + for (; table->name; table++) + tegra_clk_init_one_from_table(table); +} +EXPORT_SYMBOL(tegra_clk_init_from_table); + +void tegra_periph_reset_deassert(struct clk *c) +{ + tegra2_periph_reset_deassert(c); +} +EXPORT_SYMBOL(tegra_periph_reset_deassert); + +void tegra_periph_reset_assert(struct clk *c) +{ + tegra2_periph_reset_assert(c); +} +EXPORT_SYMBOL(tegra_periph_reset_assert); + +void __init tegra_init_clock(void) +{ + tegra2_init_clocks(); +} + +int __init tegra_init_dvfs(void) +{ + struct clk *c, *safe; + + mutex_lock(&dvfs_lock); + + list_for_each_entry_safe(c, safe, &clocks, node) + if (c->dvfs) + dvfs_init(c); + + mutex_unlock(&dvfs_lock); + + return 0; +} + +late_initcall(tegra_init_dvfs); + +#ifdef CONFIG_DEBUG_FS +static struct dentry *clk_debugfs_root; + + +static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level) +{ + struct clk *child; + struct clk *safe; + const char *state = "uninit"; + char div[8] = {0}; + + if (c->state == ON) + state = "on"; + else if (c->state == OFF) + state = "off"; + + if (c->mul != 0 && c->div != 0) { + if (c->mul > c->div) { + int mul = c->mul / c->div; + int mul2 = (c->mul * 10 / c->div) % 10; + int mul3 = (c->mul * 10) % c->div; + if (mul2 == 0 && mul3 == 0) + snprintf(div, sizeof(div), "x%d", mul); + else if (mul3 == 0) + snprintf(div, sizeof(div), "x%d.%d", mul, mul2); + else + snprintf(div, sizeof(div), "x%d.%d..", mul, mul2); + } else { + snprintf(div, sizeof(div), "%d%s", c->div / c->mul, + (c->div % c->mul) ? ".5" : ""); + } + } + + seq_printf(s, "%*s%c%c%-*s %-6s %-3d %-8s %-10lu\n", + level * 3 + 1, "", + c->rate > c->max_rate ? '!' : ' ', + !c->set ? '*' : ' ', + 30 - level * 3, c->name, + state, c->refcnt, div, c->rate); + list_for_each_entry_safe(child, safe, &c->children, sibling) { + clock_tree_show_one(s, child, level + 1); + } +} + +static int clock_tree_show(struct seq_file *s, void *data) +{ + struct clk *c; + unsigned long flags; + seq_printf(s, " clock state ref div rate\n"); + seq_printf(s, "--------------------------------------------------------------\n"); + spin_lock_irqsave(&clock_lock, flags); + list_for_each_entry(c, &clocks, node) + if (c->parent == NULL) + clock_tree_show_one(s, c, 0); + spin_unlock_irqrestore(&clock_lock, flags); + return 0; +} + +static int clock_tree_open(struct inode *inode, struct file *file) +{ + return single_open(file, clock_tree_show, inode->i_private); +} + +static const struct file_operations clock_tree_fops = { + .open = clock_tree_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int possible_parents_show(struct seq_file *s, void *data) +{ + struct clk *c = s->private; + int i; + + for (i = 0; c->inputs[i].input; i++) { + char *first = (i == 0) ? "" : " "; + seq_printf(s, "%s%s", first, c->inputs[i].input->name); + } + seq_printf(s, "\n"); + return 0; +} + +static int possible_parents_open(struct inode *inode, struct file *file) +{ + return single_open(file, possible_parents_show, inode->i_private); +} + +static const struct file_operations possible_parents_fops = { + .open = possible_parents_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int clk_debugfs_register_one(struct clk *c) +{ + struct dentry *d, *child, *child_tmp; + + d = debugfs_create_dir(c->name, clk_debugfs_root); + if (!d) + return -ENOMEM; + c->dent = d; + + d = debugfs_create_u8("refcnt", S_IRUGO, c->dent, (u8 *)&c->refcnt); + if (!d) + goto err_out; + + d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate); + if (!d) + goto err_out; + + d = debugfs_create_x32("flags", S_IRUGO, c->dent, (u32 *)&c->flags); + if (!d) + goto err_out; + + if (c->inputs) { + d = debugfs_create_file("possible_parents", S_IRUGO, c->dent, + c, &possible_parents_fops); + if (!d) + goto err_out; + } + + return 0; + +err_out: + d = c->dent; + list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child) + debugfs_remove(child); + debugfs_remove(c->dent); + return -ENOMEM; +} + +static int clk_debugfs_register(struct clk *c) +{ + int err; + struct clk *pa = c->parent; + + if (pa && !pa->dent) { + err = clk_debugfs_register(pa); + if (err) + return err; + } + + if (!c->dent) { + err = clk_debugfs_register_one(c); + if (err) + return err; + } + return 0; +} + +static int __init clk_debugfs_init(void) +{ + struct clk *c; + struct dentry *d; + int err = -ENOMEM; + + d = debugfs_create_dir("clock", NULL); + if (!d) + return -ENOMEM; + clk_debugfs_root = d; + + d = debugfs_create_file("clock_tree", S_IRUGO, clk_debugfs_root, NULL, + &clock_tree_fops); + if (!d) + goto err_out; + + list_for_each_entry(c, &clocks, node) { + err = clk_debugfs_register(c); + if (err) + goto err_out; + } + return 0; +err_out: + debugfs_remove_recursive(clk_debugfs_root); + return err; +} + +late_initcall(clk_debugfs_init); +#endif |