diff options
Diffstat (limited to 'arch/arm/mach-omap2/clock.c')
-rw-r--r-- | arch/arm/mach-omap2/clock.c | 517 |
1 files changed, 510 insertions, 7 deletions
diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index 961ac8f7e13d..33f5b5de86c3 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -15,6 +15,7 @@ #undef DEBUG #include <linux/kernel.h> +#include <linux/export.h> #include <linux/list.h> #include <linux/errno.h> #include <linux/err.h> @@ -47,6 +48,10 @@ u16 cpu_mask; */ static bool clkdm_control = true; +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); +static DEFINE_SPINLOCK(clockfw_lock); + /* * OMAP2+ specific clock functions */ @@ -512,12 +517,510 @@ void __init omap2_clk_print_new_rates(const char *hfclkin_ck_name, /* Common data */ -struct clk_functions omap2_clk_functions = { - .clk_enable = omap2_clk_enable, - .clk_disable = omap2_clk_disable, - .clk_round_rate = omap2_clk_round_rate, - .clk_set_rate = omap2_clk_set_rate, - .clk_set_parent = omap2_clk_set_parent, - .clk_disable_unused = omap2_clk_disable_unused, +int clk_enable(struct clk *clk) +{ + unsigned long flags; + int ret; + + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + spin_lock_irqsave(&clockfw_lock, flags); + ret = omap2_clk_enable(clk); + spin_unlock_irqrestore(&clockfw_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_enable); + +void clk_disable(struct clk *clk) +{ + unsigned long flags; + + if (clk == NULL || IS_ERR(clk)) + return; + + spin_lock_irqsave(&clockfw_lock, flags); + if (clk->usecount == 0) { + pr_err("Trying disable clock %s with 0 usecount\n", + clk->name); + WARN_ON(1); + goto out; + } + + omap2_clk_disable(clk); + +out: + spin_unlock_irqrestore(&clockfw_lock, flags); +} +EXPORT_SYMBOL(clk_disable); + +unsigned long clk_get_rate(struct clk *clk) +{ + unsigned long flags; + unsigned long ret; + + if (clk == NULL || IS_ERR(clk)) + return 0; + + spin_lock_irqsave(&clockfw_lock, flags); + ret = clk->rate; + spin_unlock_irqrestore(&clockfw_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_get_rate); + +/* + * Optional clock functions defined in include/linux/clk.h + */ + +long clk_round_rate(struct clk *clk, unsigned long rate) +{ + unsigned long flags; + long ret; + + if (clk == NULL || IS_ERR(clk)) + return 0; + + spin_lock_irqsave(&clockfw_lock, flags); + ret = omap2_clk_round_rate(clk, rate); + spin_unlock_irqrestore(&clockfw_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_round_rate); + +int clk_set_rate(struct clk *clk, unsigned long rate) +{ + unsigned long flags; + int ret = -EINVAL; + + if (clk == NULL || IS_ERR(clk)) + return ret; + + spin_lock_irqsave(&clockfw_lock, flags); + ret = omap2_clk_set_rate(clk, rate); + if (ret == 0) + propagate_rate(clk); + spin_unlock_irqrestore(&clockfw_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_set_rate); + +int clk_set_parent(struct clk *clk, struct clk *parent) +{ + unsigned long flags; + int ret = -EINVAL; + + if (clk == NULL || IS_ERR(clk) || parent == NULL || IS_ERR(parent)) + return ret; + + spin_lock_irqsave(&clockfw_lock, flags); + if (clk->usecount == 0) { + ret = omap2_clk_set_parent(clk, parent); + if (ret == 0) + propagate_rate(clk); + } else { + ret = -EBUSY; + } + spin_unlock_irqrestore(&clockfw_lock, flags); + + return ret; +} +EXPORT_SYMBOL(clk_set_parent); + +struct clk *clk_get_parent(struct clk *clk) +{ + return clk->parent; +} +EXPORT_SYMBOL(clk_get_parent); + +/* + * OMAP specific clock functions shared between omap1 and omap2 + */ + +int __initdata mpurate; + +/* + * By default we use the rate set by the bootloader. + * You can override this with mpurate= cmdline option. + */ +static int __init omap_clk_setup(char *str) +{ + get_option(&str, &mpurate); + + if (!mpurate) + return 1; + + if (mpurate < 1000) + mpurate *= 1000000; + + return 1; +} +__setup("mpurate=", omap_clk_setup); + +/* Used for clocks that always have same value as the parent clock */ +unsigned long followparent_recalc(struct clk *clk) +{ + return clk->parent->rate; +} + +/* + * Used for clocks that have the same value as the parent clock, + * divided by some factor + */ +unsigned long omap_fixed_divisor_recalc(struct clk *clk) +{ + WARN_ON(!clk->fixed_div); + + return clk->parent->rate / clk->fixed_div; +} + +void clk_reparent(struct clk *child, struct clk *parent) +{ + list_del_init(&child->sibling); + if (parent) + list_add(&child->sibling, &parent->children); + child->parent = parent; + + /* now do the debugfs renaming to reattach the child + to the proper parent */ +} + +/* Propagate rate to children */ +void propagate_rate(struct clk *tclk) +{ + struct clk *clkp; + + list_for_each_entry(clkp, &tclk->children, sibling) { + if (clkp->recalc) + clkp->rate = clkp->recalc(clkp); + propagate_rate(clkp); + } +} + +static LIST_HEAD(root_clks); + +/** + * recalculate_root_clocks - recalculate and propagate all root clocks + * + * Recalculates all root clocks (clocks with no parent), which if the + * clock's .recalc is set correctly, should also propagate their rates. + * Called at init. + */ +void recalculate_root_clocks(void) +{ + struct clk *clkp; + + list_for_each_entry(clkp, &root_clks, sibling) { + if (clkp->recalc) + clkp->rate = clkp->recalc(clkp); + propagate_rate(clkp); + } +} + +/** + * clk_preinit - initialize any fields in the struct clk before clk init + * @clk: struct clk * to initialize + * + * Initialize any struct clk fields needed before normal clk initialization + * can run. No return value. + */ +void clk_preinit(struct clk *clk) +{ + INIT_LIST_HEAD(&clk->children); +} + +int clk_register(struct clk *clk) +{ + if (clk == NULL || IS_ERR(clk)) + return -EINVAL; + + /* + * trap out already registered clocks + */ + if (clk->node.next || clk->node.prev) + return 0; + + mutex_lock(&clocks_mutex); + if (clk->parent) + list_add(&clk->sibling, &clk->parent->children); + else + list_add(&clk->sibling, &root_clks); + + list_add(&clk->node, &clocks); + if (clk->init) + clk->init(clk); + mutex_unlock(&clocks_mutex); + + return 0; +} +EXPORT_SYMBOL(clk_register); + +void clk_unregister(struct clk *clk) +{ + if (clk == NULL || IS_ERR(clk)) + return; + + mutex_lock(&clocks_mutex); + list_del(&clk->sibling); + list_del(&clk->node); + mutex_unlock(&clocks_mutex); +} +EXPORT_SYMBOL(clk_unregister); + +void clk_enable_init_clocks(void) +{ + struct clk *clkp; + + list_for_each_entry(clkp, &clocks, node) + if (clkp->flags & ENABLE_ON_INIT) + clk_enable(clkp); +} + +/** + * omap_clk_get_by_name - locate OMAP struct clk by its name + * @name: name of the struct clk to locate + * + * Locate an OMAP struct clk by its name. Assumes that struct clk + * names are unique. Returns NULL if not found or a pointer to the + * struct clk if found. + */ +struct clk *omap_clk_get_by_name(const char *name) +{ + struct clk *c; + struct clk *ret = NULL; + + mutex_lock(&clocks_mutex); + + list_for_each_entry(c, &clocks, node) { + if (!strcmp(c->name, name)) { + ret = c; + break; + } + } + + mutex_unlock(&clocks_mutex); + + return ret; +} + +int omap_clk_enable_autoidle_all(void) +{ + struct clk *c; + unsigned long flags; + + spin_lock_irqsave(&clockfw_lock, flags); + + list_for_each_entry(c, &clocks, node) + if (c->ops->allow_idle) + c->ops->allow_idle(c); + + spin_unlock_irqrestore(&clockfw_lock, flags); + + return 0; +} + +int omap_clk_disable_autoidle_all(void) +{ + struct clk *c; + unsigned long flags; + + spin_lock_irqsave(&clockfw_lock, flags); + + list_for_each_entry(c, &clocks, node) + if (c->ops->deny_idle) + c->ops->deny_idle(c); + + spin_unlock_irqrestore(&clockfw_lock, flags); + + return 0; +} + +/* + * Low level helpers + */ +static int clkll_enable_null(struct clk *clk) +{ + return 0; +} + +static void clkll_disable_null(struct clk *clk) +{ +} + +const struct clkops clkops_null = { + .enable = clkll_enable_null, + .disable = clkll_disable_null, +}; + +/* + * Dummy clock + * + * Used for clock aliases that are needed on some OMAPs, but not others + */ +struct clk dummy_ck = { + .name = "dummy", + .ops = &clkops_null, +}; + +/* + * + */ + +#ifdef CONFIG_OMAP_RESET_CLOCKS +/* + * Disable any unused clocks left on by the bootloader + */ +static int __init clk_disable_unused(void) +{ + struct clk *ck; + unsigned long flags; + + pr_info("clock: disabling unused clocks to save power\n"); + + spin_lock_irqsave(&clockfw_lock, flags); + list_for_each_entry(ck, &clocks, node) { + if (ck->ops == &clkops_null) + continue; + + if (ck->usecount > 0 || !ck->enable_reg) + continue; + + omap2_clk_disable_unused(ck); + } + spin_unlock_irqrestore(&clockfw_lock, flags); + + return 0; +} +late_initcall(clk_disable_unused); +late_initcall(omap_clk_enable_autoidle_all); +#endif + +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) +/* + * debugfs support to trace clock tree hierarchy and attributes + */ + +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +static struct dentry *clk_debugfs_root; + +static int clk_dbg_show_summary(struct seq_file *s, void *unused) +{ + struct clk *c; + struct clk *pa; + + mutex_lock(&clocks_mutex); + seq_printf(s, "%-30s %-30s %-10s %s\n", + "clock-name", "parent-name", "rate", "use-count"); + + list_for_each_entry(c, &clocks, node) { + pa = c->parent; + seq_printf(s, "%-30s %-30s %-10lu %d\n", + c->name, pa ? pa->name : "none", c->rate, + c->usecount); + } + mutex_unlock(&clocks_mutex); + + return 0; +} + +static int clk_dbg_open(struct inode *inode, struct file *file) +{ + return single_open(file, clk_dbg_show_summary, inode->i_private); +} + +static const struct file_operations debug_clock_fops = { + .open = clk_dbg_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, }; +static int clk_debugfs_register_one(struct clk *c) +{ + int err; + struct dentry *d; + struct clk *pa = c->parent; + + d = debugfs_create_dir(c->name, pa ? pa->dent : clk_debugfs_root); + if (!d) + return -ENOMEM; + c->dent = d; + + d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8 *)&c->usecount); + if (!d) { + err = -ENOMEM; + goto err_out; + } + d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate); + if (!d) { + err = -ENOMEM; + goto err_out; + } + d = debugfs_create_x32("flags", S_IRUGO, c->dent, (u32 *)&c->flags); + if (!d) { + err = -ENOMEM; + goto err_out; + } + return 0; + +err_out: + debugfs_remove_recursive(c->dent); + return err; +} + +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; + + d = debugfs_create_dir("clock", NULL); + if (!d) + return -ENOMEM; + clk_debugfs_root = d; + + list_for_each_entry(c, &clocks, node) { + err = clk_debugfs_register(c); + if (err) + goto err_out; + } + + d = debugfs_create_file("summary", S_IRUGO, + d, NULL, &debug_clock_fops); + if (!d) + return -ENOMEM; + + return 0; +err_out: + debugfs_remove_recursive(clk_debugfs_root); + return err; +} +late_initcall(clk_debugfs_init); + +#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */ + |