diff options
Diffstat (limited to 'arch/arm/mach-tegra/clock.c')
-rw-r--r-- | arch/arm/mach-tegra/clock.c | 574 |
1 files changed, 35 insertions, 539 deletions
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c index 58f981c0819c..fd82085eca5d 100644 --- a/arch/arm/mach-tegra/clock.c +++ b/arch/arm/mach-tegra/clock.c @@ -1,6 +1,7 @@ /* * * Copyright (C) 2010 Google, Inc. + * Copyright (c) 2012 NVIDIA CORPORATION. All rights reserved. * * Author: * Colin Cross <ccross@google.com> @@ -19,8 +20,6 @@ #include <linux/kernel.h> #include <linux/clk.h> #include <linux/clkdev.h> -#include <linux/debugfs.h> -#include <linux/delay.h> #include <linux/init.h> #include <linux/list.h> #include <linux/module.h> @@ -32,325 +31,75 @@ #include "board.h" #include "clock.h" +#include "tegra_cpu_car.h" + +/* Global data of Tegra CPU CAR ops */ +struct tegra_cpu_car_ops *tegra_cpu_car_ops; /* * Locking: * - * Each struct clk has a spinlock. - * - * To avoid AB-BA locking problems, locks must always be traversed from child - * clock to parent clock. For example, when enabling a clock, the clock's lock - * is taken, and then clk_enable is called on the parent, which take's the - * parent clock's lock. There is one exceptions to this ordering: When dumping - * the clock tree through debugfs. In this case, clk_lock_all is called, - * which attemps to iterate through the entire list of clocks and take every - * clock lock. If any call to spin_trylock fails, all locked clocks are - * unlocked, and the process is retried. When all the locks are held, - * the only clock operation that can be called is clk_get_rate_all_locked. - * - * Within a single clock, no clock operation can call another clock operation - * on itself, except for clk_get_rate_locked and clk_set_rate_locked. Any - * clock operation can call any other clock operation on any of it's possible - * parents. - * * An additional mutex, clock_list_lock, is used to protect the list of all * clocks. * - * The clock operations must lock internally to protect against - * read-modify-write on registers that are shared by multiple clocks */ static DEFINE_MUTEX(clock_list_lock); static LIST_HEAD(clocks); -struct clk *tegra_get_clock_by_name(const char *name) -{ - struct clk *c; - struct clk *ret = NULL; - mutex_lock(&clock_list_lock); - list_for_each_entry(c, &clocks, node) { - if (strcmp(c->name, name) == 0) { - ret = c; - break; - } - } - mutex_unlock(&clock_list_lock); - return ret; -} - -/* Must be called with c->spinlock held */ -static unsigned long clk_predict_rate_from_parent(struct clk *c, struct clk *p) -{ - u64 rate; - - rate = clk_get_rate(p); - - if (c->mul != 0 && c->div != 0) { - rate *= c->mul; - rate += c->div - 1; /* round up */ - do_div(rate, c->div); - } - - return rate; -} - -/* Must be called with c->spinlock held */ -unsigned long clk_get_rate_locked(struct clk *c) -{ - unsigned long rate; - - if (c->parent) - rate = clk_predict_rate_from_parent(c, c->parent); - else - rate = c->rate; - - return rate; -} - -unsigned long clk_get_rate(struct clk *c) +void tegra_clk_add(struct clk *clk) { - unsigned long flags; - unsigned long rate; - - spin_lock_irqsave(&c->spinlock, flags); - - rate = clk_get_rate_locked(c); - - spin_unlock_irqrestore(&c->spinlock, flags); - - return rate; -} -EXPORT_SYMBOL(clk_get_rate); - -int clk_reparent(struct clk *c, struct clk *parent) -{ - c->parent = parent; - return 0; -} - -void clk_init(struct clk *c) -{ - spin_lock_init(&c->spinlock); - - if (c->ops && c->ops->init) - c->ops->init(c); - - if (!c->ops || !c->ops->enable) { - c->refcnt++; - c->set = true; - if (c->parent) - c->state = c->parent->state; - else - c->state = ON; - } + struct clk_tegra *c = to_clk_tegra(__clk_get_hw(clk)); mutex_lock(&clock_list_lock); list_add(&c->node, &clocks); mutex_unlock(&clock_list_lock); } -int clk_enable(struct clk *c) -{ - int ret = 0; - unsigned long flags; - - spin_lock_irqsave(&c->spinlock, flags); - - if (c->refcnt == 0) { - if (c->parent) { - ret = clk_enable(c->parent); - if (ret) - goto out; - } - - if (c->ops && c->ops->enable) { - ret = c->ops->enable(c); - if (ret) { - if (c->parent) - clk_disable(c->parent); - goto out; - } - c->state = ON; - c->set = true; - } - } - c->refcnt++; -out: - spin_unlock_irqrestore(&c->spinlock, flags); - return ret; -} -EXPORT_SYMBOL(clk_enable); - -void clk_disable(struct clk *c) -{ - unsigned long flags; - - spin_lock_irqsave(&c->spinlock, flags); - - if (c->refcnt == 0) { - WARN(1, "Attempting to disable clock %s with refcnt 0", c->name); - spin_unlock_irqrestore(&c->spinlock, flags); - return; - } - if (c->refcnt == 1) { - if (c->ops && c->ops->disable) - c->ops->disable(c); - - if (c->parent) - clk_disable(c->parent); - - c->state = OFF; - } - c->refcnt--; - - spin_unlock_irqrestore(&c->spinlock, flags); -} -EXPORT_SYMBOL(clk_disable); - -int clk_set_parent(struct clk *c, struct clk *parent) -{ - int ret; - unsigned long flags; - unsigned long new_rate; - unsigned long old_rate; - - spin_lock_irqsave(&c->spinlock, flags); - - if (!c->ops || !c->ops->set_parent) { - ret = -ENOSYS; - goto out; - } - - new_rate = clk_predict_rate_from_parent(c, parent); - old_rate = clk_get_rate_locked(c); - - ret = c->ops->set_parent(c, parent); - if (ret) - goto out; - -out: - spin_unlock_irqrestore(&c->spinlock, 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) -{ - long new_rate; - - if (!c->ops || !c->ops->set_rate) - return -ENOSYS; - - if (rate > c->max_rate) - rate = c->max_rate; - - if (c->ops && c->ops->round_rate) { - new_rate = c->ops->round_rate(c, rate); - - if (new_rate < 0) - return new_rate; - - rate = new_rate; - } - - return c->ops->set_rate(c, rate); -} - -int clk_set_rate(struct clk *c, unsigned long rate) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&c->spinlock, flags); - - ret = clk_set_rate_locked(c, rate); - - spin_unlock_irqrestore(&c->spinlock, flags); - - return ret; -} -EXPORT_SYMBOL(clk_set_rate); - - -/* Must be called with clocks lock and all indvidual clock locks held */ -unsigned long clk_get_rate_all_locked(struct clk *c) +struct clk *tegra_get_clock_by_name(const char *name) { - u64 rate; - int mul = 1; - int div = 1; - struct clk *p = c; - - while (p) { - c = p; - if (c->mul != 0 && c->div != 0) { - mul *= c->mul; - div *= c->div; + struct clk_tegra *c; + struct clk *ret = NULL; + mutex_lock(&clock_list_lock); + list_for_each_entry(c, &clocks, node) { + if (strcmp(__clk_get_name(c->hw.clk), name) == 0) { + ret = c->hw.clk; + break; } - p = c->parent; - } - - rate = c->rate; - rate *= mul; - do_div(rate, div); - - return rate; -} - -long clk_round_rate(struct clk *c, unsigned long rate) -{ - unsigned long flags; - long ret; - - spin_lock_irqsave(&c->spinlock, flags); - - if (!c->ops || !c->ops->round_rate) { - ret = -ENOSYS; - goto out; } - - if (rate > c->max_rate) - rate = c->max_rate; - - ret = c->ops->round_rate(c, rate); - -out: - spin_unlock_irqrestore(&c->spinlock, flags); + mutex_unlock(&clock_list_lock); return ret; } -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; + struct clk *parent; int ret = 0; c = tegra_get_clock_by_name(table->name); if (!c) { - pr_warning("Unable to initialize clock %s\n", + pr_warn("Unable to initialize clock %s\n", table->name); return -ENODEV; } + parent = clk_get_parent(c); + if (table->parent) { p = tegra_get_clock_by_name(table->parent); if (!p) { - pr_warning("Unable to find parent %s of clock %s\n", + pr_warn("Unable to find parent %s of clock %s\n", table->parent, table->name); return -ENODEV; } - if (c->parent != p) { + if (parent != p) { ret = clk_set_parent(c, p); if (ret) { - pr_warning("Unable to set parent %s of clock %s: %d\n", + pr_warn("Unable to set parent %s of clock %s: %d\n", table->parent, table->name, ret); return -EINVAL; } @@ -360,16 +109,16 @@ static int tegra_clk_init_one_from_table(struct tegra_clk_init_table *table) 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", + pr_warn("Unable to set clock %s to rate %lu: %d\n", table->name, table->rate, ret); return -EINVAL; } } if (table->enabled) { - ret = clk_enable(c); + ret = clk_prepare_enable(c); if (ret) { - pr_warning("Unable to enable clock %s: %d\n", + pr_warn("Unable to enable clock %s: %d\n", table->name, ret); return -EINVAL; } @@ -383,19 +132,20 @@ 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) { - BUG_ON(!c->ops->reset); - c->ops->reset(c, false); + struct clk_tegra *clk = to_clk_tegra(__clk_get_hw(c)); + BUG_ON(!clk->reset); + clk->reset(__clk_get_hw(c), false); } EXPORT_SYMBOL(tegra_periph_reset_deassert); void tegra_periph_reset_assert(struct clk *c) { - BUG_ON(!c->ops->reset); - c->ops->reset(c, true); + struct clk_tegra *clk = to_clk_tegra(__clk_get_hw(c)); + BUG_ON(!clk->reset); + clk->reset(__clk_get_hw(c), true); } EXPORT_SYMBOL(tegra_periph_reset_assert); @@ -405,268 +155,14 @@ EXPORT_SYMBOL(tegra_periph_reset_assert); int tegra_clk_cfg_ex(struct clk *c, enum tegra_clk_ex_param p, u32 setting) { int ret = 0; - unsigned long flags; + struct clk_tegra *clk = to_clk_tegra(__clk_get_hw(c)); - spin_lock_irqsave(&c->spinlock, flags); - - if (!c->ops || !c->ops->clk_cfg_ex) { + if (!clk->clk_cfg_ex) { ret = -ENOSYS; goto out; } - ret = c->ops->clk_cfg_ex(c, p, setting); + ret = clk->clk_cfg_ex(__clk_get_hw(c), p, setting); out: - spin_unlock_irqrestore(&c->spinlock, flags); - return ret; } - -#ifdef CONFIG_DEBUG_FS - -static int __clk_lock_all_spinlocks(void) -{ - struct clk *c; - - list_for_each_entry(c, &clocks, node) - if (!spin_trylock(&c->spinlock)) - goto unlock_spinlocks; - - return 0; - -unlock_spinlocks: - list_for_each_entry_continue_reverse(c, &clocks, node) - spin_unlock(&c->spinlock); - - return -EAGAIN; -} - -static void __clk_unlock_all_spinlocks(void) -{ - struct clk *c; - - list_for_each_entry_reverse(c, &clocks, node) - spin_unlock(&c->spinlock); -} - -/* - * This function retries until it can take all locks, and may take - * an arbitrarily long time to complete. - * Must be called with irqs enabled, returns with irqs disabled - * Must be called with clock_list_lock held - */ -static void clk_lock_all(void) -{ - int ret; -retry: - local_irq_disable(); - - ret = __clk_lock_all_spinlocks(); - if (ret) - goto failed_spinlocks; - - /* All locks taken successfully, return */ - return; - -failed_spinlocks: - local_irq_enable(); - yield(); - goto retry; -} - -/* - * Unlocks all clocks after a clk_lock_all - * Must be called with irqs disabled, returns with irqs enabled - * Must be called with clock_list_lock held - */ -static void clk_unlock_all(void) -{ - __clk_unlock_all_spinlocks(); - - local_irq_enable(); -} - -static struct dentry *clk_debugfs_root; - - -static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level) -{ - struct clk *child; - 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, clk_get_rate_all_locked(c)); - - list_for_each_entry(child, &clocks, node) { - if (child->parent != c) - continue; - - clock_tree_show_one(s, child, level + 1); - } -} - -static int clock_tree_show(struct seq_file *s, void *data) -{ - struct clk *c; - seq_printf(s, " clock state ref div rate\n"); - seq_printf(s, "--------------------------------------------------------------\n"); - - mutex_lock(&clock_list_lock); - - clk_lock_all(); - - list_for_each_entry(c, &clocks, node) - if (c->parent == NULL) - clock_tree_show_one(s, c, 0); - - clk_unlock_all(); - - mutex_unlock(&clock_list_lock); - 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; - - 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: - debugfs_remove_recursive(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; -} - -int __init tegra_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; -} - -#endif |