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-rw-r--r--arch/arm/mach-omap2/clock.c517
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) */
+