* Standard functionality for the common clock API. See Documentation/clk.txt
*/
-#include <linux/clk-private.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clk/clk-conf.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/sched.h>
+#include <linux/clkdev.h>
+
+#include "clk.h"
static DEFINE_SPINLOCK(enable_lock);
static DEFINE_MUTEX(prepare_lock);
static HLIST_HEAD(clk_orphan_list);
static LIST_HEAD(clk_notifier_list);
+/*** private data structures ***/
+
+struct clk_core {
+ const char *name;
+ const struct clk_ops *ops;
+ struct clk_hw *hw;
+ struct module *owner;
+ struct clk_core *parent;
+ const char **parent_names;
+ struct clk_core **parents;
+ u8 num_parents;
+ u8 new_parent_index;
+ unsigned long rate;
+ unsigned long req_rate;
+ unsigned long new_rate;
+ struct clk_core *new_parent;
+ struct clk_core *new_child;
+ unsigned long flags;
+ bool orphan;
+ unsigned int enable_count;
+ unsigned int prepare_count;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ unsigned long accuracy;
+ int phase;
+ struct hlist_head children;
+ struct hlist_node child_node;
+ struct hlist_head clks;
+ unsigned int notifier_count;
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *dentry;
+ struct hlist_node debug_node;
+#endif
+ struct kref ref;
+};
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/clk.h>
+
+struct clk {
+ struct clk_core *core;
+ const char *dev_id;
+ const char *con_id;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ struct hlist_node clks_node;
+};
+
/*** locking ***/
static void clk_prepare_lock(void)
{
}
static unsigned long clk_enable_lock(void)
+ __acquires(enable_lock)
{
unsigned long flags;
if (!spin_trylock_irqsave(&enable_lock, flags)) {
if (enable_owner == current) {
enable_refcnt++;
+ __acquire(enable_lock);
return flags;
}
spin_lock_irqsave(&enable_lock, flags);
}
static void clk_enable_unlock(unsigned long flags)
+ __releases(enable_lock)
{
WARN_ON_ONCE(enable_owner != current);
WARN_ON_ONCE(enable_refcnt == 0);
- if (--enable_refcnt)
+ if (--enable_refcnt) {
+ __release(enable_lock);
return;
+ }
enable_owner = NULL;
spin_unlock_irqrestore(&enable_lock, flags);
}
-/*** debugfs support ***/
+static bool clk_core_is_prepared(struct clk_core *core)
+{
+ /*
+ * .is_prepared is optional for clocks that can prepare
+ * fall back to software usage counter if it is missing
+ */
+ if (!core->ops->is_prepared)
+ return core->prepare_count;
-#ifdef CONFIG_COMMON_CLK_DEBUG
-#include <linux/debugfs.h>
+ return core->ops->is_prepared(core->hw);
+}
-static struct dentry *rootdir;
-static struct dentry *orphandir;
-static int inited = 0;
+static bool clk_core_is_enabled(struct clk_core *core)
+{
+ /*
+ * .is_enabled is only mandatory for clocks that gate
+ * fall back to software usage counter if .is_enabled is missing
+ */
+ if (!core->ops->is_enabled)
+ return core->enable_count;
+
+ return core->ops->is_enabled(core->hw);
+}
-static void clk_summary_show_one(struct seq_file *s, struct clk *c, int level)
+static void clk_unprepare_unused_subtree(struct clk_core *core)
{
- if (!c)
+ struct clk_core *child;
+
+ lockdep_assert_held(&prepare_lock);
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_unprepare_unused_subtree(child);
+
+ if (core->prepare_count)
return;
- seq_printf(s, "%*s%-*s %-11d %-12d %-10lu",
- level * 3 + 1, "",
- 30 - level * 3, c->name,
- c->enable_count, c->prepare_count, c->rate);
- seq_printf(s, "\n");
+ if (core->flags & CLK_IGNORE_UNUSED)
+ return;
+
+ if (clk_core_is_prepared(core)) {
+ trace_clk_unprepare(core);
+ if (core->ops->unprepare_unused)
+ core->ops->unprepare_unused(core->hw);
+ else if (core->ops->unprepare)
+ core->ops->unprepare(core->hw);
+ trace_clk_unprepare_complete(core);
+ }
}
-static void clk_summary_show_subtree(struct seq_file *s, struct clk *c,
- int level)
+static void clk_disable_unused_subtree(struct clk_core *core)
{
- struct clk *child;
+ struct clk_core *child;
+ unsigned long flags;
- if (!c)
- return;
+ lockdep_assert_held(&prepare_lock);
- clk_summary_show_one(s, c, level);
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_disable_unused_subtree(child);
- hlist_for_each_entry(child, &c->children, child_node)
- clk_summary_show_subtree(s, child, level + 1);
+ flags = clk_enable_lock();
+
+ if (core->enable_count)
+ goto unlock_out;
+
+ if (core->flags & CLK_IGNORE_UNUSED)
+ goto unlock_out;
+
+ /*
+ * some gate clocks have special needs during the disable-unused
+ * sequence. call .disable_unused if available, otherwise fall
+ * back to .disable
+ */
+ if (clk_core_is_enabled(core)) {
+ trace_clk_disable(core);
+ if (core->ops->disable_unused)
+ core->ops->disable_unused(core->hw);
+ else if (core->ops->disable)
+ core->ops->disable(core->hw);
+ trace_clk_disable_complete(core);
+ }
+
+unlock_out:
+ clk_enable_unlock(flags);
}
-static int clk_summary_show(struct seq_file *s, void *data)
+static bool clk_ignore_unused;
+static int __init clk_ignore_unused_setup(char *__unused)
+{
+ clk_ignore_unused = true;
+ return 1;
+}
+__setup("clk_ignore_unused", clk_ignore_unused_setup);
+
+static int clk_disable_unused(void)
{
- struct clk *c;
+ struct clk_core *core;
- seq_printf(s, " clock enable_cnt prepare_cnt rate\n");
- seq_printf(s, "---------------------------------------------------------------------\n");
+ if (clk_ignore_unused) {
+ pr_warn("clk: Not disabling unused clocks\n");
+ return 0;
+ }
clk_prepare_lock();
- hlist_for_each_entry(c, &clk_root_list, child_node)
- clk_summary_show_subtree(s, c, 0);
+ hlist_for_each_entry(core, &clk_root_list, child_node)
+ clk_disable_unused_subtree(core);
- hlist_for_each_entry(c, &clk_orphan_list, child_node)
- clk_summary_show_subtree(s, c, 0);
+ hlist_for_each_entry(core, &clk_orphan_list, child_node)
+ clk_disable_unused_subtree(core);
+
+ hlist_for_each_entry(core, &clk_root_list, child_node)
+ clk_unprepare_unused_subtree(core);
+
+ hlist_for_each_entry(core, &clk_orphan_list, child_node)
+ clk_unprepare_unused_subtree(core);
clk_prepare_unlock();
return 0;
}
+late_initcall_sync(clk_disable_unused);
+/*** helper functions ***/
-static int clk_summary_open(struct inode *inode, struct file *file)
+const char *__clk_get_name(const struct clk *clk)
{
- return single_open(file, clk_summary_show, inode->i_private);
+ return !clk ? NULL : clk->core->name;
}
+EXPORT_SYMBOL_GPL(__clk_get_name);
-static const struct file_operations clk_summary_fops = {
- .open = clk_summary_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
+const char *clk_hw_get_name(const struct clk_hw *hw)
+{
+ return hw->core->name;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_name);
-static void clk_dump_one(struct seq_file *s, struct clk *c, int level)
+struct clk_hw *__clk_get_hw(struct clk *clk)
{
- if (!c)
- return;
+ return !clk ? NULL : clk->core->hw;
+}
+EXPORT_SYMBOL_GPL(__clk_get_hw);
- seq_printf(s, "\"%s\": { ", c->name);
- seq_printf(s, "\"enable_count\": %d,", c->enable_count);
- seq_printf(s, "\"prepare_count\": %d,", c->prepare_count);
- seq_printf(s, "\"rate\": %lu", c->rate);
+unsigned int clk_hw_get_num_parents(const struct clk_hw *hw)
+{
+ return hw->core->num_parents;
}
+EXPORT_SYMBOL_GPL(clk_hw_get_num_parents);
-static void clk_dump_subtree(struct seq_file *s, struct clk *c, int level)
+struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
{
- struct clk *child;
+ return hw->core->parent ? hw->core->parent->hw : NULL;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_parent);
- if (!c)
- return;
+static struct clk_core *__clk_lookup_subtree(const char *name,
+ struct clk_core *core)
+{
+ struct clk_core *child;
+ struct clk_core *ret;
- clk_dump_one(s, c, level);
+ if (!strcmp(core->name, name))
+ return core;
- hlist_for_each_entry(child, &c->children, child_node) {
- seq_printf(s, ",");
- clk_dump_subtree(s, child, level + 1);
+ hlist_for_each_entry(child, &core->children, child_node) {
+ ret = __clk_lookup_subtree(name, child);
+ if (ret)
+ return ret;
}
- seq_printf(s, "}");
+ return NULL;
}
-static int clk_dump(struct seq_file *s, void *data)
+static struct clk_core *clk_core_lookup(const char *name)
{
- struct clk *c;
- bool first_node = true;
-
- seq_printf(s, "{");
+ struct clk_core *root_clk;
+ struct clk_core *ret;
- clk_prepare_lock();
+ if (!name)
+ return NULL;
- hlist_for_each_entry(c, &clk_root_list, child_node) {
- if (!first_node)
- seq_printf(s, ",");
- first_node = false;
- clk_dump_subtree(s, c, 0);
+ /* search the 'proper' clk tree first */
+ hlist_for_each_entry(root_clk, &clk_root_list, child_node) {
+ ret = __clk_lookup_subtree(name, root_clk);
+ if (ret)
+ return ret;
}
- hlist_for_each_entry(c, &clk_orphan_list, child_node) {
- seq_printf(s, ",");
- clk_dump_subtree(s, c, 0);
+ /* if not found, then search the orphan tree */
+ hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) {
+ ret = __clk_lookup_subtree(name, root_clk);
+ if (ret)
+ return ret;
}
- clk_prepare_unlock();
-
- seq_printf(s, "}");
- return 0;
+ return NULL;
}
+static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
+ u8 index)
+{
+ if (!core || index >= core->num_parents)
+ return NULL;
+ else if (!core->parents)
+ return clk_core_lookup(core->parent_names[index]);
+ else if (!core->parents[index])
+ return core->parents[index] =
+ clk_core_lookup(core->parent_names[index]);
+ else
+ return core->parents[index];
+}
-static int clk_dump_open(struct inode *inode, struct file *file)
+struct clk_hw *
+clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index)
{
- return single_open(file, clk_dump, inode->i_private);
+ struct clk_core *parent;
+
+ parent = clk_core_get_parent_by_index(hw->core, index);
+
+ return !parent ? NULL : parent->hw;
}
+EXPORT_SYMBOL_GPL(clk_hw_get_parent_by_index);
-static const struct file_operations clk_dump_fops = {
- .open = clk_dump_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
+unsigned int __clk_get_enable_count(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->enable_count;
+}
-/* caller must hold prepare_lock */
-static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry)
+static unsigned long clk_core_get_rate_nolock(struct clk_core *core)
{
- struct dentry *d;
- int ret = -ENOMEM;
+ unsigned long ret;
- if (!clk || !pdentry) {
- ret = -EINVAL;
+ if (!core) {
+ ret = 0;
goto out;
}
- d = debugfs_create_dir(clk->name, pdentry);
- if (!d)
- goto out;
+ ret = core->rate;
- clk->dentry = d;
+ if (core->flags & CLK_IS_ROOT)
+ goto out;
- d = debugfs_create_u32("clk_rate", S_IRUGO, clk->dentry,
- (u32 *)&clk->rate);
- if (!d)
- goto err_out;
+ if (!core->parent)
+ ret = 0;
- d = debugfs_create_x32("clk_flags", S_IRUGO, clk->dentry,
- (u32 *)&clk->flags);
- if (!d)
- goto err_out;
+out:
+ return ret;
+}
- d = debugfs_create_u32("clk_prepare_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->prepare_count);
- if (!d)
- goto err_out;
+unsigned long clk_hw_get_rate(const struct clk_hw *hw)
+{
+ return clk_core_get_rate_nolock(hw->core);
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_rate);
- d = debugfs_create_u32("clk_enable_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->enable_count);
- if (!d)
- goto err_out;
+static unsigned long __clk_get_accuracy(struct clk_core *core)
+{
+ if (!core)
+ return 0;
- d = debugfs_create_u32("clk_notifier_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->notifier_count);
- if (!d)
- goto err_out;
+ return core->accuracy;
+}
- ret = 0;
- goto out;
+unsigned long __clk_get_flags(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->flags;
+}
+EXPORT_SYMBOL_GPL(__clk_get_flags);
-err_out:
- debugfs_remove(clk->dentry);
-out:
- return ret;
+unsigned long clk_hw_get_flags(const struct clk_hw *hw)
+{
+ return hw->core->flags;
}
+EXPORT_SYMBOL_GPL(clk_hw_get_flags);
-/* caller must hold prepare_lock */
-static int clk_debug_create_subtree(struct clk *clk, struct dentry *pdentry)
+bool clk_hw_is_prepared(const struct clk_hw *hw)
{
- struct clk *child;
- int ret = -EINVAL;;
+ return clk_core_is_prepared(hw->core);
+}
- if (!clk || !pdentry)
- goto out;
+bool clk_hw_is_enabled(const struct clk_hw *hw)
+{
+ return clk_core_is_enabled(hw->core);
+}
- ret = clk_debug_create_one(clk, pdentry);
+bool __clk_is_enabled(struct clk *clk)
+{
+ if (!clk)
+ return false;
- if (ret)
- goto out;
+ return clk_core_is_enabled(clk->core);
+}
+EXPORT_SYMBOL_GPL(__clk_is_enabled);
- hlist_for_each_entry(child, &clk->children, child_node)
- clk_debug_create_subtree(child, clk->dentry);
+static bool mux_is_better_rate(unsigned long rate, unsigned long now,
+ unsigned long best, unsigned long flags)
+{
+ if (flags & CLK_MUX_ROUND_CLOSEST)
+ return abs(now - rate) < abs(best - rate);
- ret = 0;
-out:
- return ret;
+ return now <= rate && now > best;
}
-/**
- * clk_debug_register - add a clk node to the debugfs clk tree
- * @clk: the clk being added to the debugfs clk tree
- *
- * Dynamically adds a clk to the debugfs clk tree if debugfs has been
- * initialized. Otherwise it bails out early since the debugfs clk tree
- * will be created lazily by clk_debug_init as part of a late_initcall.
- *
- * Caller must hold prepare_lock. Only clk_init calls this function (so
- * far) so this is taken care.
- */
-static int clk_debug_register(struct clk *clk)
+static int
+clk_mux_determine_rate_flags(struct clk_hw *hw, struct clk_rate_request *req,
+ unsigned long flags)
{
- struct clk *parent;
- struct dentry *pdentry;
- int ret = 0;
+ struct clk_core *core = hw->core, *parent, *best_parent = NULL;
+ int i, num_parents, ret;
+ unsigned long best = 0;
+ struct clk_rate_request parent_req = *req;
+
+ /* if NO_REPARENT flag set, pass through to current parent */
+ if (core->flags & CLK_SET_RATE_NO_REPARENT) {
+ parent = core->parent;
+ if (core->flags & CLK_SET_RATE_PARENT) {
+ ret = __clk_determine_rate(parent ? parent->hw : NULL,
+ &parent_req);
+ if (ret)
+ return ret;
+
+ best = parent_req.rate;
+ } else if (parent) {
+ best = clk_core_get_rate_nolock(parent);
+ } else {
+ best = clk_core_get_rate_nolock(core);
+ }
- if (!inited)
goto out;
+ }
- parent = clk->parent;
+ /* find the parent that can provide the fastest rate <= rate */
+ num_parents = core->num_parents;
+ for (i = 0; i < num_parents; i++) {
+ parent = clk_core_get_parent_by_index(core, i);
+ if (!parent)
+ continue;
- /*
- * Check to see if a clk is a root clk. Also check that it is
- * safe to add this clk to debugfs
- */
- if (!parent)
- if (clk->flags & CLK_IS_ROOT)
- pdentry = rootdir;
- else
- pdentry = orphandir;
- else
- if (parent->dentry)
- pdentry = parent->dentry;
- else
- goto out;
+ if (core->flags & CLK_SET_RATE_PARENT) {
+ parent_req = *req;
+ ret = __clk_determine_rate(parent->hw, &parent_req);
+ if (ret)
+ continue;
+ } else {
+ parent_req.rate = clk_core_get_rate_nolock(parent);
+ }
+
+ if (mux_is_better_rate(req->rate, parent_req.rate,
+ best, flags)) {
+ best_parent = parent;
+ best = parent_req.rate;
+ }
+ }
- ret = clk_debug_create_subtree(clk, pdentry);
+ if (!best_parent)
+ return -EINVAL;
out:
- return ret;
+ if (best_parent)
+ req->best_parent_hw = best_parent->hw;
+ req->best_parent_rate = best;
+ req->rate = best;
+
+ return 0;
}
-/**
- * clk_debug_reparent - reparent clk node in the debugfs clk tree
- * @clk: the clk being reparented
- * @new_parent: the new clk parent, may be NULL
- *
- * Rename clk entry in the debugfs clk tree if debugfs has been
- * initialized. Otherwise it bails out early since the debugfs clk tree
- * will be created lazily by clk_debug_init as part of a late_initcall.
- *
- * Caller must hold prepare_lock.
- */
-static void clk_debug_reparent(struct clk *clk, struct clk *new_parent)
+struct clk *__clk_lookup(const char *name)
{
- struct dentry *d;
- struct dentry *new_parent_d;
+ struct clk_core *core = clk_core_lookup(name);
- if (!inited)
- return;
+ return !core ? NULL : core->hw->clk;
+}
- if (new_parent)
- new_parent_d = new_parent->dentry;
- else
- new_parent_d = orphandir;
+static void clk_core_get_boundaries(struct clk_core *core,
+ unsigned long *min_rate,
+ unsigned long *max_rate)
+{
+ struct clk *clk_user;
- d = debugfs_rename(clk->dentry->d_parent, clk->dentry,
- new_parent_d, clk->name);
- if (d)
- clk->dentry = d;
- else
- pr_debug("%s: failed to rename debugfs entry for %s\n",
- __func__, clk->name);
+ *min_rate = core->min_rate;
+ *max_rate = core->max_rate;
+
+ hlist_for_each_entry(clk_user, &core->clks, clks_node)
+ *min_rate = max(*min_rate, clk_user->min_rate);
+
+ hlist_for_each_entry(clk_user, &core->clks, clks_node)
+ *max_rate = min(*max_rate, clk_user->max_rate);
}
-/**
- * clk_debug_init - lazily create the debugfs clk tree visualization
- *
- * clks are often initialized very early during boot before memory can
- * be dynamically allocated and well before debugfs is setup.
- * clk_debug_init walks the clk tree hierarchy while holding
- * prepare_lock and creates the topology as part of a late_initcall,
- * thus insuring that clks initialized very early will still be
- * represented in the debugfs clk tree. This function should only be
- * called once at boot-time, and all other clks added dynamically will
- * be done so with clk_debug_register.
+void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
+ unsigned long max_rate)
+{
+ hw->core->min_rate = min_rate;
+ hw->core->max_rate = max_rate;
+}
+EXPORT_SYMBOL_GPL(clk_hw_set_rate_range);
+
+/*
+ * Helper for finding best parent to provide a given frequency. This can be used
+ * directly as a determine_rate callback (e.g. for a mux), or from a more
+ * complex clock that may combine a mux with other operations.
*/
-static int __init clk_debug_init(void)
+int __clk_mux_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
{
- struct clk *clk;
- struct dentry *d;
+ return clk_mux_determine_rate_flags(hw, req, 0);
+}
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
- rootdir = debugfs_create_dir("clk", NULL);
+int __clk_mux_determine_rate_closest(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST);
+}
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
- if (!rootdir)
- return -ENOMEM;
+/*** clk api ***/
- d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, NULL,
- &clk_summary_fops);
- if (!d)
- return -ENOMEM;
-
- d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, NULL,
- &clk_dump_fops);
- if (!d)
- return -ENOMEM;
-
- orphandir = debugfs_create_dir("orphans", rootdir);
-
- if (!orphandir)
- return -ENOMEM;
-
- clk_prepare_lock();
-
- hlist_for_each_entry(clk, &clk_root_list, child_node)
- clk_debug_create_subtree(clk, rootdir);
-
- hlist_for_each_entry(clk, &clk_orphan_list, child_node)
- clk_debug_create_subtree(clk, orphandir);
-
- inited = 1;
-
- clk_prepare_unlock();
-
- return 0;
-}
-late_initcall(clk_debug_init);
-#else
-static inline int clk_debug_register(struct clk *clk) { return 0; }
-static inline void clk_debug_reparent(struct clk *clk, struct clk *new_parent)
-{
-}
-#endif
-
-/* caller must hold prepare_lock */
-static void clk_unprepare_unused_subtree(struct clk *clk)
+static void clk_core_unprepare(struct clk_core *core)
{
- struct clk *child;
-
- if (!clk)
- return;
-
- hlist_for_each_entry(child, &clk->children, child_node)
- clk_unprepare_unused_subtree(child);
+ lockdep_assert_held(&prepare_lock);
- if (clk->prepare_count)
+ if (!core)
return;
- if (clk->flags & CLK_IGNORE_UNUSED)
- return;
-
- if (__clk_is_prepared(clk)) {
- if (clk->ops->unprepare_unused)
- clk->ops->unprepare_unused(clk->hw);
- else if (clk->ops->unprepare)
- clk->ops->unprepare(clk->hw);
- }
-}
-EXPORT_SYMBOL_GPL(__clk_get_flags);
-
-/* caller must hold prepare_lock */
-static void clk_disable_unused_subtree(struct clk *clk)
-{
- struct clk *child;
- unsigned long flags;
-
- if (!clk)
- goto out;
-
- hlist_for_each_entry(child, &clk->children, child_node)
- clk_disable_unused_subtree(child);
-
- flags = clk_enable_lock();
-
- if (clk->enable_count)
- goto unlock_out;
-
- if (clk->flags & CLK_IGNORE_UNUSED)
- goto unlock_out;
-
- /*
- * some gate clocks have special needs during the disable-unused
- * sequence. call .disable_unused if available, otherwise fall
- * back to .disable
- */
- if (__clk_is_enabled(clk)) {
- if (clk->ops->disable_unused)
- clk->ops->disable_unused(clk->hw);
- else if (clk->ops->disable)
- clk->ops->disable(clk->hw);
- }
-
-unlock_out:
- clk_enable_unlock(flags);
-
-out:
- return;
-}
-
-static bool clk_ignore_unused;
-static int __init clk_ignore_unused_setup(char *__unused)
-{
- clk_ignore_unused = true;
- return 1;
-}
-__setup("clk_ignore_unused", clk_ignore_unused_setup);
-
-static int clk_disable_unused(void)
-{
- struct clk *clk;
-
- if (clk_ignore_unused) {
- pr_warn("clk: Not disabling unused clocks\n");
- return 0;
- }
-
- clk_prepare_lock();
-
- hlist_for_each_entry(clk, &clk_root_list, child_node)
- clk_disable_unused_subtree(clk);
-
- hlist_for_each_entry(clk, &clk_orphan_list, child_node)
- clk_disable_unused_subtree(clk);
-
- hlist_for_each_entry(clk, &clk_root_list, child_node)
- clk_unprepare_unused_subtree(clk);
-
- hlist_for_each_entry(clk, &clk_orphan_list, child_node)
- clk_unprepare_unused_subtree(clk);
-
- clk_prepare_unlock();
-
- return 0;
-}
-late_initcall(clk_disable_unused);
-
-/*** helper functions ***/
-
-const char *__clk_get_name(struct clk *clk)
-{
- return !clk ? NULL : clk->name;
-}
-EXPORT_SYMBOL_GPL(__clk_get_name);
-
-struct clk_hw *__clk_get_hw(struct clk *clk)
-{
- return !clk ? NULL : clk->hw;
-}
-
-u8 __clk_get_num_parents(struct clk *clk)
-{
- return !clk ? 0 : clk->num_parents;
-}
-
-struct clk *__clk_get_parent(struct clk *clk)
-{
- return !clk ? NULL : clk->parent;
-}
-
-unsigned int __clk_get_enable_count(struct clk *clk)
-{
- return !clk ? 0 : clk->enable_count;
-}
-
-unsigned int __clk_get_prepare_count(struct clk *clk)
-{
- return !clk ? 0 : clk->prepare_count;
-}
-
-unsigned long __clk_get_rate(struct clk *clk)
-{
- unsigned long ret;
-
- if (!clk) {
- ret = 0;
- goto out;
- }
-
- ret = clk->rate;
-
- if (clk->flags & CLK_IS_ROOT)
- goto out;
-
- if (!clk->parent)
- ret = 0;
-
-out:
- return ret;
-}
-
-unsigned long __clk_get_flags(struct clk *clk)
-{
- return !clk ? 0 : clk->flags;
-}
-
-bool __clk_is_prepared(struct clk *clk)
-{
- int ret;
-
- if (!clk)
- return false;
-
- /*
- * .is_prepared is optional for clocks that can prepare
- * fall back to software usage counter if it is missing
- */
- if (!clk->ops->is_prepared) {
- ret = clk->prepare_count ? 1 : 0;
- goto out;
- }
-
- ret = clk->ops->is_prepared(clk->hw);
-out:
- return !!ret;
-}
-
-bool __clk_is_enabled(struct clk *clk)
-{
- int ret;
-
- if (!clk)
- return false;
-
- /*
- * .is_enabled is only mandatory for clocks that gate
- * fall back to software usage counter if .is_enabled is missing
- */
- if (!clk->ops->is_enabled) {
- ret = clk->enable_count ? 1 : 0;
- goto out;
- }
-
- ret = clk->ops->is_enabled(clk->hw);
-out:
- return !!ret;
-}
-
-static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk)
-{
- struct clk *child;
- struct clk *ret;
-
- if (!strcmp(clk->name, name))
- return clk;
-
- hlist_for_each_entry(child, &clk->children, child_node) {
- ret = __clk_lookup_subtree(name, child);
- if (ret)
- return ret;
- }
-
- return NULL;
-}
-
-struct clk *__clk_lookup(const char *name)
-{
- struct clk *root_clk;
- struct clk *ret;
-
- if (!name)
- return NULL;
-
- /* search the 'proper' clk tree first */
- hlist_for_each_entry(root_clk, &clk_root_list, child_node) {
- ret = __clk_lookup_subtree(name, root_clk);
- if (ret)
- return ret;
- }
-
- /* if not found, then search the orphan tree */
- hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) {
- ret = __clk_lookup_subtree(name, root_clk);
- if (ret)
- return ret;
- }
-
- return NULL;
-}
-
-/*** clk api ***/
-
-void __clk_unprepare(struct clk *clk)
-{
- if (!clk)
+ if (WARN_ON(core->prepare_count == 0))
return;
- if (WARN_ON(clk->prepare_count == 0))
+ if (--core->prepare_count > 0)
return;
- if (--clk->prepare_count > 0)
- return;
+ WARN_ON(core->enable_count > 0);
- WARN_ON(clk->enable_count > 0);
+ trace_clk_unprepare(core);
- if (clk->ops->unprepare)
- clk->ops->unprepare(clk->hw);
+ if (core->ops->unprepare)
+ core->ops->unprepare(core->hw);
- __clk_unprepare(clk->parent);
+ trace_clk_unprepare_complete(core);
+ clk_core_unprepare(core->parent);
}
/**
* clk_unprepare - undo preparation of a clock source
- * @clk: the clk being unprepare
+ * @clk: the clk being unprepared
*
* clk_unprepare may sleep, which differentiates it from clk_disable. In a
* simple case, clk_unprepare can be used instead of clk_disable to gate a clk
*/
void clk_unprepare(struct clk *clk)
{
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
clk_prepare_lock();
- __clk_unprepare(clk);
+ clk_core_unprepare(clk->core);
clk_prepare_unlock();
}
EXPORT_SYMBOL_GPL(clk_unprepare);
-int __clk_prepare(struct clk *clk)
+static int clk_core_prepare(struct clk_core *core)
{
int ret = 0;
- if (!clk)
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
return 0;
- if (clk->prepare_count == 0) {
- ret = __clk_prepare(clk->parent);
+ if (core->prepare_count == 0) {
+ ret = clk_core_prepare(core->parent);
if (ret)
return ret;
- if (clk->ops->prepare) {
- ret = clk->ops->prepare(clk->hw);
- if (ret) {
- __clk_unprepare(clk->parent);
- return ret;
- }
+ trace_clk_prepare(core);
+
+ if (core->ops->prepare)
+ ret = core->ops->prepare(core->hw);
+
+ trace_clk_prepare_complete(core);
+
+ if (ret) {
+ clk_core_unprepare(core->parent);
+ return ret;
}
}
- clk->prepare_count++;
+ core->prepare_count++;
return 0;
}
{
int ret;
+ if (!clk)
+ return 0;
+
clk_prepare_lock();
- ret = __clk_prepare(clk);
+ ret = clk_core_prepare(clk->core);
clk_prepare_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(clk_prepare);
-static void __clk_disable(struct clk *clk)
+static void clk_core_disable(struct clk_core *core)
{
- if (!clk)
- return;
+ lockdep_assert_held(&enable_lock);
- if (WARN_ON(IS_ERR(clk)))
+ if (!core)
return;
- if (WARN_ON(clk->enable_count == 0))
+ if (WARN_ON(core->enable_count == 0))
return;
- if (--clk->enable_count > 0)
+ if (--core->enable_count > 0)
return;
- if (clk->ops->disable)
- clk->ops->disable(clk->hw);
+ trace_clk_disable(core);
- __clk_disable(clk->parent);
+ if (core->ops->disable)
+ core->ops->disable(core->hw);
+
+ trace_clk_disable_complete(core);
+
+ clk_core_disable(core->parent);
}
/**
{
unsigned long flags;
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
flags = clk_enable_lock();
- __clk_disable(clk);
+ clk_core_disable(clk->core);
clk_enable_unlock(flags);
}
EXPORT_SYMBOL_GPL(clk_disable);
-static int __clk_enable(struct clk *clk)
+static int clk_core_enable(struct clk_core *core)
{
int ret = 0;
- if (!clk)
+ lockdep_assert_held(&enable_lock);
+
+ if (!core)
return 0;
- if (WARN_ON(clk->prepare_count == 0))
+ if (WARN_ON(core->prepare_count == 0))
return -ESHUTDOWN;
- if (clk->enable_count == 0) {
- ret = __clk_enable(clk->parent);
+ if (core->enable_count == 0) {
+ ret = clk_core_enable(core->parent);
if (ret)
return ret;
- if (clk->ops->enable) {
- ret = clk->ops->enable(clk->hw);
- if (ret) {
- __clk_disable(clk->parent);
- return ret;
- }
+ trace_clk_enable(core);
+
+ if (core->ops->enable)
+ ret = core->ops->enable(core->hw);
+
+ trace_clk_enable_complete(core);
+
+ if (ret) {
+ clk_core_disable(core->parent);
+ return ret;
}
}
- clk->enable_count++;
+ core->enable_count++;
return 0;
}
unsigned long flags;
int ret;
+ if (!clk)
+ return 0;
+
flags = clk_enable_lock();
- ret = __clk_enable(clk);
+ ret = clk_core_enable(clk->core);
clk_enable_unlock(flags);
return ret;
}
EXPORT_SYMBOL_GPL(clk_enable);
-/**
- * __clk_round_rate - round the given rate for a clk
- * @clk: round the rate of this clock
- *
- * Caller must hold prepare_lock. Useful for clk_ops such as .set_rate
- */
-unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
+static int clk_core_round_rate_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
{
- unsigned long parent_rate = 0;
+ struct clk_core *parent;
+ long rate;
- if (!clk)
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
return 0;
- if (!clk->ops->round_rate) {
- if (clk->flags & CLK_SET_RATE_PARENT)
- return __clk_round_rate(clk->parent, rate);
- else
- return clk->rate;
+ parent = core->parent;
+ if (parent) {
+ req->best_parent_hw = parent->hw;
+ req->best_parent_rate = parent->rate;
+ } else {
+ req->best_parent_hw = NULL;
+ req->best_parent_rate = 0;
}
- if (clk->parent)
- parent_rate = clk->parent->rate;
+ if (core->ops->determine_rate) {
+ return core->ops->determine_rate(core->hw, req);
+ } else if (core->ops->round_rate) {
+ rate = core->ops->round_rate(core->hw, req->rate,
+ &req->best_parent_rate);
+ if (rate < 0)
+ return rate;
+
+ req->rate = rate;
+ } else if (core->flags & CLK_SET_RATE_PARENT) {
+ return clk_core_round_rate_nolock(parent, req);
+ } else {
+ req->rate = core->rate;
+ }
- return clk->ops->round_rate(clk->hw, rate, &parent_rate);
+ return 0;
}
/**
- * clk_round_rate - round the given rate for a clk
- * @clk: the clk for which we are rounding a rate
- * @rate: the rate which is to be rounded
+ * __clk_determine_rate - get the closest rate actually supported by a clock
+ * @hw: determine the rate of this clock
+ * @rate: target rate
+ * @min_rate: returned rate must be greater than this rate
+ * @max_rate: returned rate must be less than this rate
*
- * Takes in a rate as input and rounds it to a rate that the clk can actually
- * use which is then returned. If clk doesn't support round_rate operation
+ * Useful for clk_ops such as .set_rate and .determine_rate.
+ */
+int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ if (!hw) {
+ req->rate = 0;
+ return 0;
+ }
+
+ return clk_core_round_rate_nolock(hw->core, req);
+}
+EXPORT_SYMBOL_GPL(__clk_determine_rate);
+
+unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate)
+{
+ int ret;
+ struct clk_rate_request req;
+
+ clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
+
+ ret = clk_core_round_rate_nolock(hw->core, &req);
+ if (ret)
+ return 0;
+
+ return req.rate;
+}
+EXPORT_SYMBOL_GPL(clk_hw_round_rate);
+
+/**
+ * clk_round_rate - round the given rate for a clk
+ * @clk: the clk for which we are rounding a rate
+ * @rate: the rate which is to be rounded
+ *
+ * Takes in a rate as input and rounds it to a rate that the clk can actually
+ * use which is then returned. If clk doesn't support round_rate operation
* then the parent rate is returned.
*/
long clk_round_rate(struct clk *clk, unsigned long rate)
{
- unsigned long ret;
+ struct clk_rate_request req;
+ int ret;
+
+ if (!clk)
+ return 0;
clk_prepare_lock();
- ret = __clk_round_rate(clk, rate);
+
+ clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
+
+ ret = clk_core_round_rate_nolock(clk->core, &req);
clk_prepare_unlock();
- return ret;
+ if (ret)
+ return ret;
+
+ return req.rate;
}
EXPORT_SYMBOL_GPL(clk_round_rate);
/**
* __clk_notify - call clk notifier chain
- * @clk: struct clk * that is changing rate
+ * @core: clk that is changing rate
* @msg: clk notifier type (see include/linux/clk.h)
* @old_rate: old clk rate
* @new_rate: new clk rate
* called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if
* a driver returns that.
*/
-static int __clk_notify(struct clk *clk, unsigned long msg,
+static int __clk_notify(struct clk_core *core, unsigned long msg,
unsigned long old_rate, unsigned long new_rate)
{
struct clk_notifier *cn;
struct clk_notifier_data cnd;
int ret = NOTIFY_DONE;
- cnd.clk = clk;
cnd.old_rate = old_rate;
cnd.new_rate = new_rate;
list_for_each_entry(cn, &clk_notifier_list, node) {
- if (cn->clk == clk) {
+ if (cn->clk->core == core) {
+ cnd.clk = cn->clk;
ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
&cnd);
- break;
}
}
return ret;
}
+/**
+ * __clk_recalc_accuracies
+ * @core: first clk in the subtree
+ *
+ * Walks the subtree of clks starting with clk and recalculates accuracies as
+ * it goes. Note that if a clk does not implement the .recalc_accuracy
+ * callback then it is assumed that the clock will take on the accuracy of its
+ * parent.
+ */
+static void __clk_recalc_accuracies(struct clk_core *core)
+{
+ unsigned long parent_accuracy = 0;
+ struct clk_core *child;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (core->parent)
+ parent_accuracy = core->parent->accuracy;
+
+ if (core->ops->recalc_accuracy)
+ core->accuracy = core->ops->recalc_accuracy(core->hw,
+ parent_accuracy);
+ else
+ core->accuracy = parent_accuracy;
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ __clk_recalc_accuracies(child);
+}
+
+static long clk_core_get_accuracy(struct clk_core *core)
+{
+ unsigned long accuracy;
+
+ clk_prepare_lock();
+ if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE))
+ __clk_recalc_accuracies(core);
+
+ accuracy = __clk_get_accuracy(core);
+ clk_prepare_unlock();
+
+ return accuracy;
+}
+
+/**
+ * clk_get_accuracy - return the accuracy of clk
+ * @clk: the clk whose accuracy is being returned
+ *
+ * Simply returns the cached accuracy of the clk, unless
+ * CLK_GET_ACCURACY_NOCACHE flag is set, which means a recalc_rate will be
+ * issued.
+ * If clk is NULL then returns 0.
+ */
+long clk_get_accuracy(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_accuracy(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_accuracy);
+
+static unsigned long clk_recalc(struct clk_core *core,
+ unsigned long parent_rate)
+{
+ if (core->ops->recalc_rate)
+ return core->ops->recalc_rate(core->hw, parent_rate);
+ return parent_rate;
+}
+
/**
* __clk_recalc_rates
- * @clk: first clk in the subtree
+ * @core: first clk in the subtree
* @msg: notification type (see include/linux/clk.h)
*
* Walks the subtree of clks starting with clk and recalculates rates as it
* goes. Note that if a clk does not implement the .recalc_rate callback then
- * it is assumed that the clock will take on the rate of it's parent.
+ * it is assumed that the clock will take on the rate of its parent.
*
* clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
* if necessary.
- *
- * Caller must hold prepare_lock.
*/
-static void __clk_recalc_rates(struct clk *clk, unsigned long msg)
+static void __clk_recalc_rates(struct clk_core *core, unsigned long msg)
{
unsigned long old_rate;
unsigned long parent_rate = 0;
- struct clk *child;
+ struct clk_core *child;
- old_rate = clk->rate;
+ lockdep_assert_held(&prepare_lock);
- if (clk->parent)
- parent_rate = clk->parent->rate;
+ old_rate = core->rate;
- if (clk->ops->recalc_rate)
- clk->rate = clk->ops->recalc_rate(clk->hw, parent_rate);
- else
- clk->rate = parent_rate;
+ if (core->parent)
+ parent_rate = core->parent->rate;
+
+ core->rate = clk_recalc(core, parent_rate);
/*
* ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
* & ABORT_RATE_CHANGE notifiers
*/
- if (clk->notifier_count && msg)
- __clk_notify(clk, msg, old_rate, clk->rate);
+ if (core->notifier_count && msg)
+ __clk_notify(core, msg, old_rate, core->rate);
- hlist_for_each_entry(child, &clk->children, child_node)
+ hlist_for_each_entry(child, &core->children, child_node)
__clk_recalc_rates(child, msg);
}
+static unsigned long clk_core_get_rate(struct clk_core *core)
+{
+ unsigned long rate;
+
+ clk_prepare_lock();
+
+ if (core && (core->flags & CLK_GET_RATE_NOCACHE))
+ __clk_recalc_rates(core, 0);
+
+ rate = clk_core_get_rate_nolock(core);
+ clk_prepare_unlock();
+
+ return rate;
+}
+
/**
* clk_get_rate - return the rate of clk
* @clk: the clk whose rate is being returned
*/
unsigned long clk_get_rate(struct clk *clk)
{
- unsigned long rate;
+ if (!clk)
+ return 0;
- clk_prepare_lock();
+ return clk_core_get_rate(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_rate);
+
+static int clk_fetch_parent_index(struct clk_core *core,
+ struct clk_core *parent)
+{
+ int i;
- if (clk && (clk->flags & CLK_GET_RATE_NOCACHE))
- __clk_recalc_rates(clk, 0);
+ if (!core->parents) {
+ core->parents = kcalloc(core->num_parents,
+ sizeof(struct clk *), GFP_KERNEL);
+ if (!core->parents)
+ return -ENOMEM;
+ }
- rate = __clk_get_rate(clk);
- clk_prepare_unlock();
+ /*
+ * find index of new parent clock using cached parent ptrs,
+ * or if not yet cached, use string name comparison and cache
+ * them now to avoid future calls to clk_core_lookup.
+ */
+ for (i = 0; i < core->num_parents; i++) {
+ if (core->parents[i] == parent)
+ return i;
- return rate;
+ if (core->parents[i])
+ continue;
+
+ if (!strcmp(core->parent_names[i], parent->name)) {
+ core->parents[i] = clk_core_lookup(parent->name);
+ return i;
+ }
+ }
+
+ return -EINVAL;
+}
+
+/*
+ * Update the orphan status of @core and all its children.
+ */
+static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan)
+{
+ struct clk_core *child;
+
+ core->orphan = is_orphan;
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_core_update_orphan_status(child, is_orphan);
+}
+
+static void clk_reparent(struct clk_core *core, struct clk_core *new_parent)
+{
+ bool was_orphan = core->orphan;
+
+ hlist_del(&core->child_node);
+
+ if (new_parent) {
+ bool becomes_orphan = new_parent->orphan;
+
+ /* avoid duplicate POST_RATE_CHANGE notifications */
+ if (new_parent->new_child == core)
+ new_parent->new_child = NULL;
+
+ hlist_add_head(&core->child_node, &new_parent->children);
+
+ if (was_orphan != becomes_orphan)
+ clk_core_update_orphan_status(core, becomes_orphan);
+ } else {
+ hlist_add_head(&core->child_node, &clk_orphan_list);
+ if (!was_orphan)
+ clk_core_update_orphan_status(core, true);
+ }
+
+ core->parent = new_parent;
+}
+
+static struct clk_core *__clk_set_parent_before(struct clk_core *core,
+ struct clk_core *parent)
+{
+ unsigned long flags;
+ struct clk_core *old_parent = core->parent;
+
+ /*
+ * Migrate prepare state between parents and prevent race with
+ * clk_enable().
+ *
+ * If the clock is not prepared, then a race with
+ * clk_enable/disable() is impossible since we already have the
+ * prepare lock (future calls to clk_enable() need to be preceded by
+ * a clk_prepare()).
+ *
+ * If the clock is prepared, migrate the prepared state to the new
+ * parent and also protect against a race with clk_enable() by
+ * forcing the clock and the new parent on. This ensures that all
+ * future calls to clk_enable() are practically NOPs with respect to
+ * hardware and software states.
+ *
+ * See also: Comment for clk_set_parent() below.
+ */
+ if (core->prepare_count) {
+ clk_core_prepare(parent);
+ flags = clk_enable_lock();
+ clk_core_enable(parent);
+ clk_core_enable(core);
+ clk_enable_unlock(flags);
+ }
+
+ /* update the clk tree topology */
+ flags = clk_enable_lock();
+ clk_reparent(core, parent);
+ clk_enable_unlock(flags);
+
+ return old_parent;
+}
+
+static void __clk_set_parent_after(struct clk_core *core,
+ struct clk_core *parent,
+ struct clk_core *old_parent)
+{
+ unsigned long flags;
+
+ /*
+ * Finish the migration of prepare state and undo the changes done
+ * for preventing a race with clk_enable().
+ */
+ if (core->prepare_count) {
+ flags = clk_enable_lock();
+ clk_core_disable(core);
+ clk_core_disable(old_parent);
+ clk_enable_unlock(flags);
+ clk_core_unprepare(old_parent);
+ }
+}
+
+static int __clk_set_parent(struct clk_core *core, struct clk_core *parent,
+ u8 p_index)
+{
+ unsigned long flags;
+ int ret = 0;
+ struct clk_core *old_parent;
+
+ old_parent = __clk_set_parent_before(core, parent);
+
+ trace_clk_set_parent(core, parent);
+
+ /* change clock input source */
+ if (parent && core->ops->set_parent)
+ ret = core->ops->set_parent(core->hw, p_index);
+
+ trace_clk_set_parent_complete(core, parent);
+
+ if (ret) {
+ flags = clk_enable_lock();
+ clk_reparent(core, old_parent);
+ clk_enable_unlock(flags);
+ __clk_set_parent_after(core, old_parent, parent);
+
+ return ret;
+ }
+
+ __clk_set_parent_after(core, parent, old_parent);
+
+ return 0;
}
-EXPORT_SYMBOL_GPL(clk_get_rate);
/**
* __clk_speculate_rates
- * @clk: first clk in the subtree
+ * @core: first clk in the subtree
* @parent_rate: the "future" rate of clk's parent
*
* Walks the subtree of clks starting with clk, speculating rates as it
* pre-rate change notifications and returns early if no clks in the
* subtree have subscribed to the notifications. Note that if a clk does not
* implement the .recalc_rate callback then it is assumed that the clock will
- * take on the rate of it's parent.
- *
- * Caller must hold prepare_lock.
+ * take on the rate of its parent.
*/
-static int __clk_speculate_rates(struct clk *clk, unsigned long parent_rate)
+static int __clk_speculate_rates(struct clk_core *core,
+ unsigned long parent_rate)
{
- struct clk *child;
+ struct clk_core *child;
unsigned long new_rate;
int ret = NOTIFY_DONE;
- if (clk->ops->recalc_rate)
- new_rate = clk->ops->recalc_rate(clk->hw, parent_rate);
- else
- new_rate = parent_rate;
+ lockdep_assert_held(&prepare_lock);
+
+ new_rate = clk_recalc(core, parent_rate);
/* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */
- if (clk->notifier_count)
- ret = __clk_notify(clk, PRE_RATE_CHANGE, clk->rate, new_rate);
+ if (core->notifier_count)
+ ret = __clk_notify(core, PRE_RATE_CHANGE, core->rate, new_rate);
- if (ret & NOTIFY_STOP_MASK)
+ if (ret & NOTIFY_STOP_MASK) {
+ pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n",
+ __func__, core->name, ret);
goto out;
+ }
- hlist_for_each_entry(child, &clk->children, child_node) {
+ hlist_for_each_entry(child, &core->children, child_node) {
ret = __clk_speculate_rates(child, new_rate);
if (ret & NOTIFY_STOP_MASK)
break;
return ret;
}
-static void clk_calc_subtree(struct clk *clk, unsigned long new_rate)
+static void clk_calc_subtree(struct clk_core *core, unsigned long new_rate,
+ struct clk_core *new_parent, u8 p_index)
{
- struct clk *child;
+ struct clk_core *child;
- clk->new_rate = new_rate;
+ core->new_rate = new_rate;
+ core->new_parent = new_parent;
+ core->new_parent_index = p_index;
+ /* include clk in new parent's PRE_RATE_CHANGE notifications */
+ core->new_child = NULL;
+ if (new_parent && new_parent != core->parent)
+ new_parent->new_child = core;
- hlist_for_each_entry(child, &clk->children, child_node) {
- if (child->ops->recalc_rate)
- child->new_rate = child->ops->recalc_rate(child->hw, new_rate);
- else
- child->new_rate = new_rate;
- clk_calc_subtree(child, child->new_rate);
+ hlist_for_each_entry(child, &core->children, child_node) {
+ child->new_rate = clk_recalc(child, new_rate);
+ clk_calc_subtree(child, child->new_rate, NULL, 0);
}
}
* calculate the new rates returning the topmost clock that has to be
* changed.
*/
-static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate)
+static struct clk_core *clk_calc_new_rates(struct clk_core *core,
+ unsigned long rate)
{
- struct clk *top = clk;
+ struct clk_core *top = core;
+ struct clk_core *old_parent, *parent;
unsigned long best_parent_rate = 0;
unsigned long new_rate;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ int p_index = 0;
+ long ret;
/* sanity */
- if (IS_ERR_OR_NULL(clk))
+ if (IS_ERR_OR_NULL(core))
return NULL;
/* save parent rate, if it exists */
- if (clk->parent)
- best_parent_rate = clk->parent->rate;
+ parent = old_parent = core->parent;
+ if (parent)
+ best_parent_rate = parent->rate;
+
+ clk_core_get_boundaries(core, &min_rate, &max_rate);
+
+ /* find the closest rate and parent clk/rate */
+ if (core->ops->determine_rate) {
+ struct clk_rate_request req;
+
+ req.rate = rate;
+ req.min_rate = min_rate;
+ req.max_rate = max_rate;
+ if (parent) {
+ req.best_parent_hw = parent->hw;
+ req.best_parent_rate = parent->rate;
+ } else {
+ req.best_parent_hw = NULL;
+ req.best_parent_rate = 0;
+ }
- /* never propagate up to the parent */
- if (!(clk->flags & CLK_SET_RATE_PARENT)) {
- if (!clk->ops->round_rate) {
- clk->new_rate = clk->rate;
+ ret = core->ops->determine_rate(core->hw, &req);
+ if (ret < 0)
return NULL;
- }
- new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate);
+
+ best_parent_rate = req.best_parent_rate;
+ new_rate = req.rate;
+ parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
+ } else if (core->ops->round_rate) {
+ ret = core->ops->round_rate(core->hw, rate,
+ &best_parent_rate);
+ if (ret < 0)
+ return NULL;
+
+ new_rate = ret;
+ if (new_rate < min_rate || new_rate > max_rate)
+ return NULL;
+ } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) {
+ /* pass-through clock without adjustable parent */
+ core->new_rate = core->rate;
+ return NULL;
+ } else {
+ /* pass-through clock with adjustable parent */
+ top = clk_calc_new_rates(parent, rate);
+ new_rate = parent->new_rate;
goto out;
}
- /* need clk->parent from here on out */
- if (!clk->parent) {
- pr_debug("%s: %s has NULL parent\n", __func__, clk->name);
+ /* some clocks must be gated to change parent */
+ if (parent != old_parent &&
+ (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
+ pr_debug("%s: %s not gated but wants to reparent\n",
+ __func__, core->name);
return NULL;
}
- if (!clk->ops->round_rate) {
- top = clk_calc_new_rates(clk->parent, rate);
- new_rate = clk->parent->new_rate;
-
- goto out;
+ /* try finding the new parent index */
+ if (parent && core->num_parents > 1) {
+ p_index = clk_fetch_parent_index(core, parent);
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, core->name);
+ return NULL;
+ }
}
- new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate);
-
- if (best_parent_rate != clk->parent->rate) {
- top = clk_calc_new_rates(clk->parent, best_parent_rate);
-
- goto out;
- }
+ if ((core->flags & CLK_SET_RATE_PARENT) && parent &&
+ best_parent_rate != parent->rate)
+ top = clk_calc_new_rates(parent, best_parent_rate);
out:
- clk_calc_subtree(clk, new_rate);
+ clk_calc_subtree(core, new_rate, parent, p_index);
return top;
}
* so that in case of an error we can walk down the whole tree again and
* abort the change.
*/
-static struct clk *clk_propagate_rate_change(struct clk *clk, unsigned long event)
+static struct clk_core *clk_propagate_rate_change(struct clk_core *core,
+ unsigned long event)
{
- struct clk *child, *fail_clk = NULL;
+ struct clk_core *child, *tmp_clk, *fail_clk = NULL;
int ret = NOTIFY_DONE;
- if (clk->rate == clk->new_rate)
+ if (core->rate == core->new_rate)
return NULL;
- if (clk->notifier_count) {
- ret = __clk_notify(clk, event, clk->rate, clk->new_rate);
+ if (core->notifier_count) {
+ ret = __clk_notify(core, event, core->rate, core->new_rate);
if (ret & NOTIFY_STOP_MASK)
- fail_clk = clk;
+ fail_clk = core;
}
- hlist_for_each_entry(child, &clk->children, child_node) {
- clk = clk_propagate_rate_change(child, event);
- if (clk)
- fail_clk = clk;
+ hlist_for_each_entry(child, &core->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != core)
+ continue;
+ tmp_clk = clk_propagate_rate_change(child, event);
+ if (tmp_clk)
+ fail_clk = tmp_clk;
+ }
+
+ /* handle the new child who might not be in core->children yet */
+ if (core->new_child) {
+ tmp_clk = clk_propagate_rate_change(core->new_child, event);
+ if (tmp_clk)
+ fail_clk = tmp_clk;
}
return fail_clk;
}
+static int clk_core_set_rate_nolock(struct clk_core *core,
+ unsigned long req_rate);
+
/*
* walk down a subtree and set the new rates notifying the rate
* change on the way
*/
-static void clk_change_rate(struct clk *clk)
+static void clk_change_rate(struct clk_core *core)
{
- struct clk *child;
+ struct clk_core *child;
+ struct hlist_node *tmp;
unsigned long old_rate;
unsigned long best_parent_rate = 0;
+ bool skip_set_rate = false;
+ struct clk_core *old_parent;
- old_rate = clk->rate;
+ old_rate = core->rate;
- if (clk->parent)
- best_parent_rate = clk->parent->rate;
+ if (core->new_parent)
+ best_parent_rate = core->new_parent->rate;
+ else if (core->parent)
+ best_parent_rate = core->parent->rate;
- if (clk->ops->set_rate)
- clk->ops->set_rate(clk->hw, clk->new_rate, best_parent_rate);
+ if (core->flags & CLK_SET_RATE_UNGATE) {
+ unsigned long flags;
- if (clk->ops->recalc_rate)
- clk->rate = clk->ops->recalc_rate(clk->hw, best_parent_rate);
- else
- clk->rate = best_parent_rate;
+ clk_core_prepare(core);
+ flags = clk_enable_lock();
+ clk_core_enable(core);
+ clk_enable_unlock(flags);
+ }
+
+ if (core->new_parent && core->new_parent != core->parent) {
+ old_parent = __clk_set_parent_before(core, core->new_parent);
+ trace_clk_set_parent(core, core->new_parent);
+
+ if (core->ops->set_rate_and_parent) {
+ skip_set_rate = true;
+ core->ops->set_rate_and_parent(core->hw, core->new_rate,
+ best_parent_rate,
+ core->new_parent_index);
+ } else if (core->ops->set_parent) {
+ core->ops->set_parent(core->hw, core->new_parent_index);
+ }
+
+ trace_clk_set_parent_complete(core, core->new_parent);
+ __clk_set_parent_after(core, core->new_parent, old_parent);
+ }
+
+ trace_clk_set_rate(core, core->new_rate);
+
+ if (!skip_set_rate && core->ops->set_rate)
+ core->ops->set_rate(core->hw, core->new_rate, best_parent_rate);
+
+ trace_clk_set_rate_complete(core, core->new_rate);
+
+ core->rate = clk_recalc(core, best_parent_rate);
- if (clk->notifier_count && old_rate != clk->rate)
- __clk_notify(clk, POST_RATE_CHANGE, old_rate, clk->rate);
+ if (core->flags & CLK_SET_RATE_UNGATE) {
+ unsigned long flags;
- hlist_for_each_entry(child, &clk->children, child_node)
+ flags = clk_enable_lock();
+ clk_core_disable(core);
+ clk_enable_unlock(flags);
+ clk_core_unprepare(core);
+ }
+
+ if (core->notifier_count && old_rate != core->rate)
+ __clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate);
+
+ if (core->flags & CLK_RECALC_NEW_RATES)
+ (void)clk_calc_new_rates(core, core->new_rate);
+
+ /*
+ * Use safe iteration, as change_rate can actually swap parents
+ * for certain clock types.
+ */
+ hlist_for_each_entry_safe(child, tmp, &core->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != core)
+ continue;
clk_change_rate(child);
+ }
+
+ /* handle the new child who might not be in core->children yet */
+ if (core->new_child)
+ clk_change_rate(core->new_child);
+
+ /* handle a changed clock that needs to readjust its rate */
+ if (core->flags & CLK_KEEP_REQ_RATE && core->req_rate
+ && core->new_rate != old_rate
+ && core->new_rate != core->req_rate)
+ clk_core_set_rate_nolock(core, core->req_rate);
+}
+
+static int clk_core_set_rate_nolock(struct clk_core *core,
+ unsigned long req_rate)
+{
+ struct clk_core *top, *fail_clk;
+ unsigned long rate = req_rate;
+ int ret = 0;
+
+ if (!core)
+ return 0;
+
+ /* bail early if nothing to do */
+ if (rate == clk_core_get_rate_nolock(core)) {
+ core->req_rate = req_rate;
+ return 0;
+ }
+
+ if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
+ return -EBUSY;
+
+ /* calculate new rates and get the topmost changed clock */
+ top = clk_calc_new_rates(core, rate);
+ if (!top)
+ return -EINVAL;
+
+ /* notify that we are about to change rates */
+ fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
+ if (fail_clk) {
+ pr_debug("%s: failed to set %s rate\n", __func__,
+ fail_clk->name);
+ clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
+ return -EBUSY;
+ }
+
+ core->req_rate = req_rate;
+
+ /* change the rates */
+ clk_change_rate(top);
+
+ return ret;
}
/**
* outcome of clk's .round_rate implementation. If *parent_rate is unchanged
* after calling .round_rate then upstream parent propagation is ignored. If
* *parent_rate comes back with a new rate for clk's parent then we propagate
- * up to clk's parent and set it's rate. Upward propagation will continue
+ * up to clk's parent and set its rate. Upward propagation will continue
* until either a clk does not support the CLK_SET_RATE_PARENT flag or
* .round_rate stops requesting changes to clk's parent_rate.
*
*/
int clk_set_rate(struct clk *clk, unsigned long rate)
{
- struct clk *top, *fail_clk;
- int ret = 0;
+ int ret;
+
+ if (!clk)
+ return 0;
/* prevent racing with updates to the clock topology */
clk_prepare_lock();
- /* bail early if nothing to do */
- if (rate == clk->rate)
- goto out;
+ ret = clk_core_set_rate_nolock(clk->core, rate);
- if ((clk->flags & CLK_SET_RATE_GATE) && clk->prepare_count) {
- ret = -EBUSY;
- goto out;
- }
+ clk_prepare_unlock();
- /* calculate new rates and get the topmost changed clock */
- top = clk_calc_new_rates(clk, rate);
- if (!top) {
- ret = -EINVAL;
- goto out;
- }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate);
- /* notify that we are about to change rates */
- fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
- if (fail_clk) {
- pr_warn("%s: failed to set %s rate\n", __func__,
- fail_clk->name);
- clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
- ret = -EBUSY;
- goto out;
+/**
+ * clk_set_rate_range - set a rate range for a clock source
+ * @clk: clock source
+ * @min: desired minimum clock rate in Hz, inclusive
+ * @max: desired maximum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
+{
+ int ret = 0;
+
+ if (!clk)
+ return 0;
+
+ if (min > max) {
+ pr_err("%s: clk %s dev %s con %s: invalid range [%lu, %lu]\n",
+ __func__, clk->core->name, clk->dev_id, clk->con_id,
+ min, max);
+ return -EINVAL;
}
- /* change the rates */
- clk_change_rate(top);
+ clk_prepare_lock();
+
+ if (min != clk->min_rate || max != clk->max_rate) {
+ unsigned long rate = clk->core->req_rate;
+
+ if (!rate)
+ rate = clk->core->rate;
+
+ clk->min_rate = min;
+ clk->max_rate = max;
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ }
-out:
clk_prepare_unlock();
return ret;
}
-EXPORT_SYMBOL_GPL(clk_set_rate);
+EXPORT_SYMBOL_GPL(clk_set_rate_range);
+
+/**
+ * clk_set_min_rate - set a minimum clock rate for a clock source
+ * @clk: clock source
+ * @rate: desired minimum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_min_rate(struct clk *clk, unsigned long rate)
+{
+ if (!clk)
+ return 0;
+
+ return clk_set_rate_range(clk, rate, clk->max_rate);
+}
+EXPORT_SYMBOL_GPL(clk_set_min_rate);
+
+/**
+ * clk_set_max_rate - set a maximum clock rate for a clock source
+ * @clk: clock source
+ * @rate: desired maximum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_max_rate(struct clk *clk, unsigned long rate)
+{
+ if (!clk)
+ return 0;
+
+ return clk_set_rate_range(clk, clk->min_rate, rate);
+}
+EXPORT_SYMBOL_GPL(clk_set_max_rate);
/**
* clk_get_parent - return the parent of a clk
{
struct clk *parent;
+ if (!clk)
+ return NULL;
+
clk_prepare_lock();
- parent = __clk_get_parent(clk);
+ /* TODO: Create a per-user clk and change callers to call clk_put */
+ parent = !clk->core->parent ? NULL : clk->core->parent->hw->clk;
clk_prepare_unlock();
return parent;
*
* For single-parent clocks without .get_parent, first check to see if the
* .parents array exists, and if so use it to avoid an expensive tree
- * traversal. If .parents does not exist then walk the tree with __clk_lookup.
+ * traversal. If .parents does not exist then walk the tree.
*/
-static struct clk *__clk_init_parent(struct clk *clk)
+static struct clk_core *__clk_init_parent(struct clk_core *core)
{
- struct clk *ret = NULL;
+ struct clk_core *ret = NULL;
u8 index;
/* handle the trivial cases */
- if (!clk->num_parents)
+ if (!core->num_parents)
goto out;
- if (clk->num_parents == 1) {
- if (IS_ERR_OR_NULL(clk->parent))
- ret = clk->parent = __clk_lookup(clk->parent_names[0]);
- ret = clk->parent;
+ if (core->num_parents == 1) {
+ if (IS_ERR_OR_NULL(core->parent))
+ core->parent = clk_core_lookup(core->parent_names[0]);
+ ret = core->parent;
goto out;
}
- if (!clk->ops->get_parent) {
- WARN(!clk->ops->get_parent,
+ if (!core->ops->get_parent) {
+ WARN(!core->ops->get_parent,
"%s: multi-parent clocks must implement .get_parent\n",
__func__);
goto out;
- };
+ }
/*
- * Do our best to cache parent clocks in clk->parents. This prevents
- * unnecessary and expensive calls to __clk_lookup. We don't set
- * clk->parent here; that is done by the calling function
+ * Do our best to cache parent clocks in core->parents. This prevents
+ * unnecessary and expensive lookups. We don't set core->parent here;
+ * that is done by the calling function.
*/
- index = clk->ops->get_parent(clk->hw);
+ index = core->ops->get_parent(core->hw);
- if (!clk->parents)
- clk->parents =
- kzalloc((sizeof(struct clk*) * clk->num_parents),
+ if (!core->parents)
+ core->parents =
+ kcalloc(core->num_parents, sizeof(struct clk *),
GFP_KERNEL);
- if (!clk->parents)
- ret = __clk_lookup(clk->parent_names[index]);
- else if (!clk->parents[index])
- ret = clk->parents[index] =
- __clk_lookup(clk->parent_names[index]);
- else
- ret = clk->parents[index];
+ ret = clk_core_get_parent_by_index(core, index);
out:
return ret;
}
-static void clk_reparent(struct clk *clk, struct clk *new_parent)
+static void clk_core_reparent(struct clk_core *core,
+ struct clk_core *new_parent)
{
- hlist_del(&clk->child_node);
-
- if (new_parent)
- hlist_add_head(&clk->child_node, &new_parent->children);
- else
- hlist_add_head(&clk->child_node, &clk_orphan_list);
-
- clk->parent = new_parent;
+ clk_reparent(core, new_parent);
+ __clk_recalc_accuracies(core);
+ __clk_recalc_rates(core, POST_RATE_CHANGE);
}
-void __clk_reparent(struct clk *clk, struct clk *new_parent)
+void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
{
- clk_reparent(clk, new_parent);
- clk_debug_reparent(clk, new_parent);
- __clk_recalc_rates(clk, POST_RATE_CHANGE);
+ if (!hw)
+ return;
+
+ clk_core_reparent(hw->core, !new_parent ? NULL : new_parent->core);
}
-static u8 clk_fetch_parent_index(struct clk *clk, struct clk *parent)
+/**
+ * clk_has_parent - check if a clock is a possible parent for another
+ * @clk: clock source
+ * @parent: parent clock source
+ *
+ * This function can be used in drivers that need to check that a clock can be
+ * the parent of another without actually changing the parent.
+ *
+ * Returns true if @parent is a possible parent for @clk, false otherwise.
+ */
+bool clk_has_parent(struct clk *clk, struct clk *parent)
{
- u8 i;
+ struct clk_core *core, *parent_core;
+ unsigned int i;
- if (!clk->parents)
- clk->parents = kzalloc((sizeof(struct clk*) * clk->num_parents),
- GFP_KERNEL);
+ /* NULL clocks should be nops, so return success if either is NULL. */
+ if (!clk || !parent)
+ return true;
- /*
- * find index of new parent clock using cached parent ptrs,
- * or if not yet cached, use string name comparison and cache
- * them now to avoid future calls to __clk_lookup.
- */
- for (i = 0; i < clk->num_parents; i++) {
- if (clk->parents && clk->parents[i] == parent)
- break;
- else if (!strcmp(clk->parent_names[i], parent->name)) {
- if (clk->parents)
- clk->parents[i] = __clk_lookup(parent->name);
- break;
- }
- }
+ core = clk->core;
+ parent_core = parent->core;
- return i;
+ /* Optimize for the case where the parent is already the parent. */
+ if (core->parent == parent_core)
+ return true;
+
+ for (i = 0; i < core->num_parents; i++)
+ if (strcmp(core->parent_names[i], parent_core->name) == 0)
+ return true;
+
+ return false;
}
+EXPORT_SYMBOL_GPL(clk_has_parent);
-static int __clk_set_parent(struct clk *clk, struct clk *parent, u8 p_index)
+static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
{
- unsigned long flags;
int ret = 0;
- struct clk *old_parent = clk->parent;
- bool migrated_enable = false;
-
- /* migrate prepare */
- if (clk->prepare_count)
- __clk_prepare(parent);
-
- flags = clk_enable_lock();
-
- /* migrate enable */
- if (clk->enable_count) {
- __clk_enable(parent);
- migrated_enable = true;
- }
+ int p_index = 0;
+ unsigned long p_rate = 0;
- /* update the clk tree topology */
- clk_reparent(clk, parent);
+ if (!core)
+ return 0;
- clk_enable_unlock(flags);
+ /* prevent racing with updates to the clock topology */
+ clk_prepare_lock();
- /* change clock input source */
- if (parent && clk->ops->set_parent)
- ret = clk->ops->set_parent(clk->hw, p_index);
+ if (core->parent == parent)
+ goto out;
- if (ret) {
- /*
- * The error handling is tricky due to that we need to release
- * the spinlock while issuing the .set_parent callback. This
- * means the new parent might have been enabled/disabled in
- * between, which must be considered when doing rollback.
- */
- flags = clk_enable_lock();
+ /* verify ops for for multi-parent clks */
+ if ((core->num_parents > 1) && (!core->ops->set_parent)) {
+ ret = -ENOSYS;
+ goto out;
+ }
- clk_reparent(clk, old_parent);
+ /* check that we are allowed to re-parent if the clock is in use */
+ if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
+ ret = -EBUSY;
+ goto out;
+ }
- if (migrated_enable && clk->enable_count) {
- __clk_disable(parent);
- } else if (migrated_enable && (clk->enable_count == 0)) {
- __clk_disable(old_parent);
- } else if (!migrated_enable && clk->enable_count) {
- __clk_disable(parent);
- __clk_enable(old_parent);
+ /* try finding the new parent index */
+ if (parent) {
+ p_index = clk_fetch_parent_index(core, parent);
+ p_rate = parent->rate;
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, core->name);
+ ret = p_index;
+ goto out;
}
+ }
- clk_enable_unlock(flags);
+ /* propagate PRE_RATE_CHANGE notifications */
+ ret = __clk_speculate_rates(core, p_rate);
- if (clk->prepare_count)
- __clk_unprepare(parent);
+ /* abort if a driver objects */
+ if (ret & NOTIFY_STOP_MASK)
+ goto out;
- return ret;
- }
+ /* do the re-parent */
+ ret = __clk_set_parent(core, parent, p_index);
- /* clean up enable for old parent if migration was done */
- if (migrated_enable) {
- flags = clk_enable_lock();
- __clk_disable(old_parent);
- clk_enable_unlock(flags);
+ /* propagate rate an accuracy recalculation accordingly */
+ if (ret) {
+ __clk_recalc_rates(core, ABORT_RATE_CHANGE);
+ } else {
+ __clk_recalc_rates(core, POST_RATE_CHANGE);
+ __clk_recalc_accuracies(core);
}
- /* clean up prepare for old parent if migration was done */
- if (clk->prepare_count)
- __clk_unprepare(old_parent);
+out:
+ clk_prepare_unlock();
- /* update debugfs with new clk tree topology */
- clk_debug_reparent(clk, parent);
- return 0;
+ return ret;
}
/**
* @clk: the mux clk whose input we are switching
* @parent: the new input to clk
*
- * Re-parent clk to use parent as it's new input source. If clk has the
- * CLK_SET_PARENT_GATE flag set then clk must be gated for this
- * operation to succeed. After successfully changing clk's parent
- * clk_set_parent will update the clk topology, sysfs topology and
- * propagate rate recalculation via __clk_recalc_rates. Returns 0 on
- * success, -EERROR otherwise.
+ * Re-parent clk to use parent as its new input source. If clk is in
+ * prepared state, the clk will get enabled for the duration of this call. If
+ * that's not acceptable for a specific clk (Eg: the consumer can't handle
+ * that, the reparenting is glitchy in hardware, etc), use the
+ * CLK_SET_PARENT_GATE flag to allow reparenting only when clk is unprepared.
+ *
+ * After successfully changing clk's parent clk_set_parent will update the
+ * clk topology, sysfs topology and propagate rate recalculation via
+ * __clk_recalc_rates.
+ *
+ * Returns 0 on success, -EERROR otherwise.
*/
int clk_set_parent(struct clk *clk, struct clk *parent)
{
- int ret = 0;
- u8 p_index = 0;
- unsigned long p_rate = 0;
+ if (!clk)
+ return 0;
- if (!clk || !clk->ops)
- return -EINVAL;
+ return clk_core_set_parent(clk->core, parent ? parent->core : NULL);
+}
+EXPORT_SYMBOL_GPL(clk_set_parent);
- /* verify ops for for multi-parent clks */
- if ((clk->num_parents > 1) && (!clk->ops->set_parent))
- return -ENOSYS;
+/**
+ * clk_set_phase - adjust the phase shift of a clock signal
+ * @clk: clock signal source
+ * @degrees: number of degrees the signal is shifted
+ *
+ * Shifts the phase of a clock signal by the specified
+ * degrees. Returns 0 on success, -EERROR otherwise.
+ *
+ * This function makes no distinction about the input or reference
+ * signal that we adjust the clock signal phase against. For example
+ * phase locked-loop clock signal generators we may shift phase with
+ * respect to feedback clock signal input, but for other cases the
+ * clock phase may be shifted with respect to some other, unspecified
+ * signal.
+ *
+ * Additionally the concept of phase shift does not propagate through
+ * the clock tree hierarchy, which sets it apart from clock rates and
+ * clock accuracy. A parent clock phase attribute does not have an
+ * impact on the phase attribute of a child clock.
+ */
+int clk_set_phase(struct clk *clk, int degrees)
+{
+ int ret = -EINVAL;
+
+ if (!clk)
+ return 0;
+
+ /* sanity check degrees */
+ degrees %= 360;
+ if (degrees < 0)
+ degrees += 360;
- /* prevent racing with updates to the clock topology */
clk_prepare_lock();
- if (clk->parent == parent)
+ /* bail early if nothing to do */
+ if (degrees == clk->core->phase)
goto out;
- /* check that we are allowed to re-parent if the clock is in use */
- if ((clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count) {
- ret = -EBUSY;
- goto out;
+ trace_clk_set_phase(clk->core, degrees);
+
+ if (clk->core->ops->set_phase)
+ ret = clk->core->ops->set_phase(clk->core->hw, degrees);
+
+ trace_clk_set_phase_complete(clk->core, degrees);
+
+ if (!ret)
+ clk->core->phase = degrees;
+
+out:
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_phase);
+
+static int clk_core_get_phase(struct clk_core *core)
+{
+ int ret;
+
+ clk_prepare_lock();
+ ret = core->phase;
+ clk_prepare_unlock();
+
+ return ret;
+}
+
+/**
+ * clk_get_phase - return the phase shift of a clock signal
+ * @clk: clock signal source
+ *
+ * Returns the phase shift of a clock node in degrees, otherwise returns
+ * -EERROR.
+ */
+int clk_get_phase(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_phase(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_phase);
+
+/**
+ * clk_is_match - check if two clk's point to the same hardware clock
+ * @p: clk compared against q
+ * @q: clk compared against p
+ *
+ * Returns true if the two struct clk pointers both point to the same hardware
+ * clock node. Put differently, returns true if struct clk *p and struct clk *q
+ * share the same struct clk_core object.
+ *
+ * Returns false otherwise. Note that two NULL clks are treated as matching.
+ */
+bool clk_is_match(const struct clk *p, const struct clk *q)
+{
+ /* trivial case: identical struct clk's or both NULL */
+ if (p == q)
+ return true;
+
+ /* true if clk->core pointers match. Avoid derefing garbage */
+ if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
+ if (p->core == q->core)
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(clk_is_match);
+
+/*** debugfs support ***/
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static struct dentry *rootdir;
+static int inited = 0;
+static DEFINE_MUTEX(clk_debug_lock);
+static HLIST_HEAD(clk_debug_list);
+
+static struct hlist_head *all_lists[] = {
+ &clk_root_list,
+ &clk_orphan_list,
+ NULL,
+};
+
+static struct hlist_head *orphan_list[] = {
+ &clk_orphan_list,
+ NULL,
+};
+
+static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ if (!c)
+ return;
+
+ seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n",
+ level * 3 + 1, "",
+ 30 - level * 3, c->name,
+ c->enable_count, c->prepare_count, clk_core_get_rate(c),
+ clk_core_get_accuracy(c), clk_core_get_phase(c));
+}
+
+static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ struct clk_core *child;
+
+ if (!c)
+ return;
+
+ clk_summary_show_one(s, c, level);
+
+ hlist_for_each_entry(child, &c->children, child_node)
+ clk_summary_show_subtree(s, child, level + 1);
+}
+
+static int clk_summary_show(struct seq_file *s, void *data)
+{
+ struct clk_core *c;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
+
+ seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n");
+ seq_puts(s, "----------------------------------------------------------------------------------------\n");
+
+ clk_prepare_lock();
+
+ for (; *lists; lists++)
+ hlist_for_each_entry(c, *lists, child_node)
+ clk_summary_show_subtree(s, c, 0);
+
+ clk_prepare_unlock();
+
+ return 0;
+}
+
+
+static int clk_summary_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_summary_show, inode->i_private);
+}
+
+static const struct file_operations clk_summary_fops = {
+ .open = clk_summary_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
+{
+ if (!c)
+ return;
+
+ /* This should be JSON format, i.e. elements separated with a comma */
+ seq_printf(s, "\"%s\": { ", c->name);
+ seq_printf(s, "\"enable_count\": %d,", c->enable_count);
+ seq_printf(s, "\"prepare_count\": %d,", c->prepare_count);
+ seq_printf(s, "\"rate\": %lu,", clk_core_get_rate(c));
+ seq_printf(s, "\"accuracy\": %lu,", clk_core_get_accuracy(c));
+ seq_printf(s, "\"phase\": %d", clk_core_get_phase(c));
+}
+
+static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
+{
+ struct clk_core *child;
+
+ if (!c)
+ return;
+
+ clk_dump_one(s, c, level);
+
+ hlist_for_each_entry(child, &c->children, child_node) {
+ seq_printf(s, ",");
+ clk_dump_subtree(s, child, level + 1);
}
- /* try finding the new parent index */
- if (parent) {
- p_index = clk_fetch_parent_index(clk, parent);
- p_rate = parent->rate;
- if (p_index == clk->num_parents) {
- pr_debug("%s: clk %s can not be parent of clk %s\n",
- __func__, parent->name, clk->name);
- ret = -EINVAL;
- goto out;
+ seq_printf(s, "}");
+}
+
+static int clk_dump(struct seq_file *s, void *data)
+{
+ struct clk_core *c;
+ bool first_node = true;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
+
+ seq_printf(s, "{");
+
+ clk_prepare_lock();
+
+ for (; *lists; lists++) {
+ hlist_for_each_entry(c, *lists, child_node) {
+ if (!first_node)
+ seq_puts(s, ",");
+ first_node = false;
+ clk_dump_subtree(s, c, 0);
}
}
- /* propagate PRE_RATE_CHANGE notifications */
- if (clk->notifier_count)
- ret = __clk_speculate_rates(clk, p_rate);
+ clk_prepare_unlock();
- /* abort if a driver objects */
- if (ret & NOTIFY_STOP_MASK)
+ seq_puts(s, "}\n");
+ return 0;
+}
+
+
+static int clk_dump_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_dump, inode->i_private);
+}
+
+static const struct file_operations clk_dump_fops = {
+ .open = clk_dump_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
+{
+ struct dentry *d;
+ int ret = -ENOMEM;
+
+ if (!core || !pdentry) {
+ ret = -EINVAL;
goto out;
+ }
- /* do the re-parent */
- ret = __clk_set_parent(clk, parent, p_index);
+ d = debugfs_create_dir(core->name, pdentry);
+ if (!d)
+ goto out;
+
+ core->dentry = d;
+
+ d = debugfs_create_u32("clk_rate", S_IRUGO, core->dentry,
+ (u32 *)&core->rate);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_accuracy", S_IRUGO, core->dentry,
+ (u32 *)&core->accuracy);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_phase", S_IRUGO, core->dentry,
+ (u32 *)&core->phase);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_x32("clk_flags", S_IRUGO, core->dentry,
+ (u32 *)&core->flags);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_prepare_count", S_IRUGO, core->dentry,
+ (u32 *)&core->prepare_count);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_enable_count", S_IRUGO, core->dentry,
+ (u32 *)&core->enable_count);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_notifier_count", S_IRUGO, core->dentry,
+ (u32 *)&core->notifier_count);
+ if (!d)
+ goto err_out;
+
+ if (core->ops->debug_init) {
+ ret = core->ops->debug_init(core->hw, core->dentry);
+ if (ret)
+ goto err_out;
+ }
+
+ ret = 0;
+ goto out;
+
+err_out:
+ debugfs_remove_recursive(core->dentry);
+ core->dentry = NULL;
+out:
+ return ret;
+}
+
+/**
+ * clk_debug_register - add a clk node to the debugfs clk directory
+ * @core: the clk being added to the debugfs clk directory
+ *
+ * Dynamically adds a clk to the debugfs clk directory if debugfs has been
+ * initialized. Otherwise it bails out early since the debugfs clk directory
+ * will be created lazily by clk_debug_init as part of a late_initcall.
+ */
+static int clk_debug_register(struct clk_core *core)
+{
+ int ret = 0;
+
+ mutex_lock(&clk_debug_lock);
+ hlist_add_head(&core->debug_node, &clk_debug_list);
+
+ if (!inited)
+ goto unlock;
+
+ ret = clk_debug_create_one(core, rootdir);
+unlock:
+ mutex_unlock(&clk_debug_lock);
+
+ return ret;
+}
+
+ /**
+ * clk_debug_unregister - remove a clk node from the debugfs clk directory
+ * @core: the clk being removed from the debugfs clk directory
+ *
+ * Dynamically removes a clk and all its child nodes from the
+ * debugfs clk directory if clk->dentry points to debugfs created by
+ * clk_debug_register in __clk_init.
+ */
+static void clk_debug_unregister(struct clk_core *core)
+{
+ mutex_lock(&clk_debug_lock);
+ hlist_del_init(&core->debug_node);
+ debugfs_remove_recursive(core->dentry);
+ core->dentry = NULL;
+ mutex_unlock(&clk_debug_lock);
+}
+
+struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode,
+ void *data, const struct file_operations *fops)
+{
+ struct dentry *d = NULL;
+
+ if (hw->core->dentry)
+ d = debugfs_create_file(name, mode, hw->core->dentry, data,
+ fops);
+
+ return d;
+}
+EXPORT_SYMBOL_GPL(clk_debugfs_add_file);
+
+/**
+ * clk_debug_init - lazily populate the debugfs clk directory
+ *
+ * clks are often initialized very early during boot before memory can be
+ * dynamically allocated and well before debugfs is setup. This function
+ * populates the debugfs clk directory once at boot-time when we know that
+ * debugfs is setup. It should only be called once at boot-time, all other clks
+ * added dynamically will be done so with clk_debug_register.
+ */
+static int __init clk_debug_init(void)
+{
+ struct clk_core *core;
+ struct dentry *d;
+
+ rootdir = debugfs_create_dir("clk", NULL);
+
+ if (!rootdir)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
+ &clk_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
+ &clk_dump_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
+ &orphan_list, &clk_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
+ &orphan_list, &clk_dump_fops);
+ if (!d)
+ return -ENOMEM;
- /* propagate rate recalculation accordingly */
- if (ret)
- __clk_recalc_rates(clk, ABORT_RATE_CHANGE);
- else
- __clk_recalc_rates(clk, POST_RATE_CHANGE);
+ mutex_lock(&clk_debug_lock);
+ hlist_for_each_entry(core, &clk_debug_list, debug_node)
+ clk_debug_create_one(core, rootdir);
-out:
- clk_prepare_unlock();
+ inited = 1;
+ mutex_unlock(&clk_debug_lock);
- return ret;
+ return 0;
}
-EXPORT_SYMBOL_GPL(clk_set_parent);
+late_initcall(clk_debug_init);
+#else
+static inline int clk_debug_register(struct clk_core *core) { return 0; }
+static inline void clk_debug_reparent(struct clk_core *core,
+ struct clk_core *new_parent)
+{
+}
+static inline void clk_debug_unregister(struct clk_core *core)
+{
+}
+#endif
/**
* __clk_init - initialize the data structures in a struct clk
* @dev: device initializing this clk, placeholder for now
* @clk: clk being initialized
*
- * Initializes the lists in struct clk, queries the hardware for the
+ * Initializes the lists in struct clk_core, queries the hardware for the
* parent and rate and sets them both.
*/
-int __clk_init(struct device *dev, struct clk *clk)
+static int __clk_init(struct device *dev, struct clk *clk_user)
{
int i, ret = 0;
- struct clk *orphan;
+ struct clk_core *orphan;
struct hlist_node *tmp2;
+ struct clk_core *core;
+ unsigned long rate;
- if (!clk)
+ if (!clk_user)
return -EINVAL;
+ core = clk_user->core;
+
clk_prepare_lock();
/* check to see if a clock with this name is already registered */
- if (__clk_lookup(clk->name)) {
+ if (clk_core_lookup(core->name)) {
pr_debug("%s: clk %s already initialized\n",
- __func__, clk->name);
+ __func__, core->name);
ret = -EEXIST;
goto out;
}
/* check that clk_ops are sane. See Documentation/clk.txt */
- if (clk->ops->set_rate &&
- !(clk->ops->round_rate && clk->ops->recalc_rate)) {
- pr_warning("%s: %s must implement .round_rate & .recalc_rate\n",
- __func__, clk->name);
+ if (core->ops->set_rate &&
+ !((core->ops->round_rate || core->ops->determine_rate) &&
+ core->ops->recalc_rate)) {
+ pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
- if (clk->ops->set_parent && !clk->ops->get_parent) {
+ if (core->ops->set_parent && !core->ops->get_parent) {
pr_warning("%s: %s must implement .get_parent & .set_parent\n",
- __func__, clk->name);
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (core->ops->set_rate_and_parent &&
+ !(core->ops->set_parent && core->ops->set_rate)) {
+ pr_warn("%s: %s must implement .set_parent & .set_rate\n",
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
/* throw a WARN if any entries in parent_names are NULL */
- for (i = 0; i < clk->num_parents; i++)
- WARN(!clk->parent_names[i],
+ for (i = 0; i < core->num_parents; i++)
+ WARN(!core->parent_names[i],
"%s: invalid NULL in %s's .parent_names\n",
- __func__, clk->name);
+ __func__, core->name);
/*
* Allocate an array of struct clk *'s to avoid unnecessary string
* look-ups of clk's possible parents. This can fail for clocks passed
- * in to clk_init during early boot; thus any access to clk->parents[]
+ * in to clk_init during early boot; thus any access to core->parents[]
* must always check for a NULL pointer and try to populate it if
* necessary.
*
- * If clk->parents is not NULL we skip this entire block. This allows
- * for clock drivers to statically initialize clk->parents.
+ * If core->parents is not NULL we skip this entire block. This allows
+ * for clock drivers to statically initialize core->parents.
*/
- if (clk->num_parents > 1 && !clk->parents) {
- clk->parents = kzalloc((sizeof(struct clk*) * clk->num_parents),
- GFP_KERNEL);
+ if (core->num_parents > 1 && !core->parents) {
+ core->parents = kcalloc(core->num_parents, sizeof(struct clk *),
+ GFP_KERNEL);
/*
- * __clk_lookup returns NULL for parents that have not been
+ * clk_core_lookup returns NULL for parents that have not been
* clk_init'd; thus any access to clk->parents[] must check
* for a NULL pointer. We can always perform lazy lookups for
* missing parents later on.
*/
- if (clk->parents)
- for (i = 0; i < clk->num_parents; i++)
- clk->parents[i] =
- __clk_lookup(clk->parent_names[i]);
+ if (core->parents)
+ for (i = 0; i < core->num_parents; i++)
+ core->parents[i] =
+ clk_core_lookup(core->parent_names[i]);
}
- clk->parent = __clk_init_parent(clk);
+ core->parent = __clk_init_parent(core);
/*
- * Populate clk->parent if parent has already been __clk_init'd. If
+ * Populate core->parent if parent has already been __clk_init'd. If
* parent has not yet been __clk_init'd then place clk in the orphan
* list. If clk has set the CLK_IS_ROOT flag then place it in the root
* clk list.
* clocks and re-parent any that are children of the clock currently
* being clk_init'd.
*/
- if (clk->parent)
- hlist_add_head(&clk->child_node,
- &clk->parent->children);
- else if (clk->flags & CLK_IS_ROOT)
- hlist_add_head(&clk->child_node, &clk_root_list);
+ if (core->parent) {
+ hlist_add_head(&core->child_node,
+ &core->parent->children);
+ core->orphan = core->parent->orphan;
+ } else if (core->flags & CLK_IS_ROOT) {
+ hlist_add_head(&core->child_node, &clk_root_list);
+ core->orphan = false;
+ } else {
+ hlist_add_head(&core->child_node, &clk_orphan_list);
+ core->orphan = true;
+ }
+
+ /*
+ * Set clk's accuracy. The preferred method is to use
+ * .recalc_accuracy. For simple clocks and lazy developers the default
+ * fallback is to use the parent's accuracy. If a clock doesn't have a
+ * parent (or is orphaned) then accuracy is set to zero (perfect
+ * clock).
+ */
+ if (core->ops->recalc_accuracy)
+ core->accuracy = core->ops->recalc_accuracy(core->hw,
+ __clk_get_accuracy(core->parent));
+ else if (core->parent)
+ core->accuracy = core->parent->accuracy;
+ else
+ core->accuracy = 0;
+
+ /*
+ * Set clk's phase.
+ * Since a phase is by definition relative to its parent, just
+ * query the current clock phase, or just assume it's in phase.
+ */
+ if (core->ops->get_phase)
+ core->phase = core->ops->get_phase(core->hw);
else
- hlist_add_head(&clk->child_node, &clk_orphan_list);
+ core->phase = 0;
/*
* Set clk's rate. The preferred method is to use .recalc_rate. For
* parent's rate. If a clock doesn't have a parent (or is orphaned)
* then rate is set to zero.
*/
- if (clk->ops->recalc_rate)
- clk->rate = clk->ops->recalc_rate(clk->hw,
- __clk_get_rate(clk->parent));
- else if (clk->parent)
- clk->rate = clk->parent->rate;
+ if (core->ops->recalc_rate)
+ rate = core->ops->recalc_rate(core->hw,
+ clk_core_get_rate_nolock(core->parent));
+ else if (core->parent)
+ rate = core->parent->rate;
else
- clk->rate = 0;
+ rate = 0;
+ core->rate = rate;
/*
* walk the list of orphan clocks and reparent any that are children of
* this clock
*/
hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
- if (orphan->ops->get_parent) {
+ if (orphan->num_parents && orphan->ops->get_parent) {
i = orphan->ops->get_parent(orphan->hw);
- if (!strcmp(clk->name, orphan->parent_names[i]))
- __clk_reparent(orphan, clk);
+ if (i >= 0 && i < orphan->num_parents &&
+ !strcmp(core->name, orphan->parent_names[i]))
+ clk_core_reparent(orphan, core);
continue;
}
for (i = 0; i < orphan->num_parents; i++)
- if (!strcmp(clk->name, orphan->parent_names[i])) {
- __clk_reparent(orphan, clk);
+ if (!strcmp(core->name, orphan->parent_names[i])) {
+ clk_core_reparent(orphan, core);
break;
}
}
* The .init callback is not used by any of the basic clock types, but
* exists for weird hardware that must perform initialization magic.
* Please consider other ways of solving initialization problems before
- * using this callback, as it's use is discouraged.
+ * using this callback, as its use is discouraged.
*/
- if (clk->ops->init)
- clk->ops->init(clk->hw);
-
- clk_debug_register(clk);
+ if (core->ops->init)
+ core->ops->init(core->hw);
+ kref_init(&core->ref);
out:
clk_prepare_unlock();
+ if (!ret)
+ clk_debug_register(core);
+
return ret;
}
-/**
- * __clk_register - register a clock and return a cookie.
- *
- * Same as clk_register, except that the .clk field inside hw shall point to a
- * preallocated (generally statically allocated) struct clk. None of the fields
- * of the struct clk need to be initialized.
- *
- * The data pointed to by .init and .clk field shall NOT be marked as init
- * data.
- *
- * __clk_register is only exposed via clk-private.h and is intended for use with
- * very large numbers of clocks that need to be statically initialized. It is
- * a layering violation to include clk-private.h from any code which implements
- * a clock's .ops; as such any statically initialized clock data MUST be in a
- * separate C file from the logic that implements it's operations. Returns 0
- * on success, otherwise an error code.
- */
-struct clk *__clk_register(struct device *dev, struct clk_hw *hw)
+static struct clk *clk_hw_create_clk(struct clk_hw *hw, const char *dev_id,
+ const char *con_id)
{
- int ret;
struct clk *clk;
- clk = hw->clk;
- clk->name = hw->init->name;
- clk->ops = hw->init->ops;
- clk->hw = hw;
- clk->flags = hw->init->flags;
- clk->parent_names = hw->init->parent_names;
- clk->num_parents = hw->init->num_parents;
+ clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+ if (!clk)
+ return ERR_PTR(-ENOMEM);
+
+ clk->core = hw->core;
+ clk->dev_id = dev_id;
+ clk->con_id = con_id;
+ clk->max_rate = ULONG_MAX;
- ret = __clk_init(dev, clk);
- if (ret)
- return ERR_PTR(ret);
+ clk_prepare_lock();
+ hlist_add_head(&clk->clks_node, &hw->core->clks);
+ clk_prepare_unlock();
return clk;
}
-EXPORT_SYMBOL_GPL(__clk_register);
-static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *clk)
+struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id,
+ const char *con_id, bool with_orphans)
+{
+ /* This is to allow this function to be chained to others */
+ if (!hw || IS_ERR(hw))
+ return (struct clk *) hw;
+
+ if (hw->core->orphan && !with_orphans)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ return clk_hw_create_clk(hw, dev_id, con_id);
+}
+
+void __clk_free_clk(struct clk *clk)
+{
+ clk_prepare_lock();
+ hlist_del(&clk->clks_node);
+ clk_prepare_unlock();
+
+ kfree(clk);
+}
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * clk_register is the primary interface for populating the clock tree with new
+ * clock nodes. It returns a pointer to the newly allocated struct clk which
+ * cannot be dereferenced by driver code but may be used in conjunction with the
+ * rest of the clock API. In the event of an error clk_register will return an
+ * error code; drivers must test for an error code after calling clk_register.
+ */
+struct clk *clk_register(struct device *dev, struct clk_hw *hw)
{
int i, ret;
+ struct clk_core *core;
+
+ core = kzalloc(sizeof(*core), GFP_KERNEL);
+ if (!core) {
+ ret = -ENOMEM;
+ goto fail_out;
+ }
- clk->name = kstrdup(hw->init->name, GFP_KERNEL);
- if (!clk->name) {
- pr_err("%s: could not allocate clk->name\n", __func__);
+ core->name = kstrdup_const(hw->init->name, GFP_KERNEL);
+ if (!core->name) {
ret = -ENOMEM;
goto fail_name;
}
- clk->ops = hw->init->ops;
- clk->hw = hw;
- clk->flags = hw->init->flags;
- clk->num_parents = hw->init->num_parents;
- hw->clk = clk;
+ core->ops = hw->init->ops;
+ if (dev && dev->driver)
+ core->owner = dev->driver->owner;
+ core->hw = hw;
+ core->flags = hw->init->flags;
+ core->num_parents = hw->init->num_parents;
+ core->min_rate = 0;
+ core->max_rate = ULONG_MAX;
+ hw->core = core;
/* allocate local copy in case parent_names is __initdata */
- clk->parent_names = kzalloc((sizeof(char*) * clk->num_parents),
- GFP_KERNEL);
+ core->parent_names = kcalloc(core->num_parents, sizeof(char *),
+ GFP_KERNEL);
- if (!clk->parent_names) {
- pr_err("%s: could not allocate clk->parent_names\n", __func__);
+ if (!core->parent_names) {
ret = -ENOMEM;
goto fail_parent_names;
}
/* copy each string name in case parent_names is __initdata */
- for (i = 0; i < clk->num_parents; i++) {
- clk->parent_names[i] = kstrdup(hw->init->parent_names[i],
+ for (i = 0; i < core->num_parents; i++) {
+ core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
GFP_KERNEL);
- if (!clk->parent_names[i]) {
- pr_err("%s: could not copy parent_names\n", __func__);
+ if (!core->parent_names[i]) {
ret = -ENOMEM;
goto fail_parent_names_copy;
}
}
- ret = __clk_init(dev, clk);
+ INIT_HLIST_HEAD(&core->clks);
+
+ hw->clk = clk_hw_create_clk(hw, NULL, NULL);
+ if (IS_ERR(hw->clk)) {
+ ret = PTR_ERR(hw->clk);
+ goto fail_parent_names_copy;
+ }
+
+ ret = __clk_init(dev, hw->clk);
if (!ret)
- return 0;
+ return hw->clk;
+
+ __clk_free_clk(hw->clk);
+ hw->clk = NULL;
fail_parent_names_copy:
while (--i >= 0)
- kfree(clk->parent_names[i]);
- kfree(clk->parent_names);
+ kfree_const(core->parent_names[i]);
+ kfree(core->parent_names);
fail_parent_names:
- kfree(clk->name);
+ kfree_const(core->name);
fail_name:
- return ret;
+ kfree(core);
+fail_out:
+ return ERR_PTR(ret);
}
+EXPORT_SYMBOL_GPL(clk_register);
-/**
- * clk_register - allocate a new clock, register it and return an opaque cookie
- * @dev: device that is registering this clock
- * @hw: link to hardware-specific clock data
- *
- * clk_register is the primary interface for populating the clock tree with new
- * clock nodes. It returns a pointer to the newly allocated struct clk which
- * cannot be dereferenced by driver code but may be used in conjuction with the
- * rest of the clock API. In the event of an error clk_register will return an
- * error code; drivers must test for an error code after calling clk_register.
+/* Free memory allocated for a clock. */
+static void __clk_release(struct kref *ref)
+{
+ struct clk_core *core = container_of(ref, struct clk_core, ref);
+ int i = core->num_parents;
+
+ lockdep_assert_held(&prepare_lock);
+
+ kfree(core->parents);
+ while (--i >= 0)
+ kfree_const(core->parent_names[i]);
+
+ kfree(core->parent_names);
+ kfree_const(core->name);
+ kfree(core);
+}
+
+/*
+ * Empty clk_ops for unregistered clocks. These are used temporarily
+ * after clk_unregister() was called on a clock and until last clock
+ * consumer calls clk_put() and the struct clk object is freed.
*/
-struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+static int clk_nodrv_prepare_enable(struct clk_hw *hw)
{
- int ret;
- struct clk *clk;
+ return -ENXIO;
+}
- clk = kzalloc(sizeof(*clk), GFP_KERNEL);
- if (!clk) {
- pr_err("%s: could not allocate clk\n", __func__);
- ret = -ENOMEM;
- goto fail_out;
- }
+static void clk_nodrv_disable_unprepare(struct clk_hw *hw)
+{
+ WARN_ON_ONCE(1);
+}
- ret = _clk_register(dev, hw, clk);
- if (!ret)
- return clk;
+static int clk_nodrv_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ return -ENXIO;
+}
- kfree(clk);
-fail_out:
- return ERR_PTR(ret);
+static int clk_nodrv_set_parent(struct clk_hw *hw, u8 index)
+{
+ return -ENXIO;
}
-EXPORT_SYMBOL_GPL(clk_register);
+
+static const struct clk_ops clk_nodrv_ops = {
+ .enable = clk_nodrv_prepare_enable,
+ .disable = clk_nodrv_disable_unprepare,
+ .prepare = clk_nodrv_prepare_enable,
+ .unprepare = clk_nodrv_disable_unprepare,
+ .set_rate = clk_nodrv_set_rate,
+ .set_parent = clk_nodrv_set_parent,
+};
/**
* clk_unregister - unregister a currently registered clock
* @clk: clock to unregister
- *
- * Currently unimplemented.
*/
-void clk_unregister(struct clk *clk) {}
+void clk_unregister(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_debug_unregister(clk->core);
+
+ clk_prepare_lock();
+
+ if (clk->core->ops == &clk_nodrv_ops) {
+ pr_err("%s: unregistered clock: %s\n", __func__,
+ clk->core->name);
+ return;
+ }
+ /*
+ * Assign empty clock ops for consumers that might still hold
+ * a reference to this clock.
+ */
+ flags = clk_enable_lock();
+ clk->core->ops = &clk_nodrv_ops;
+ clk_enable_unlock(flags);
+
+ if (!hlist_empty(&clk->core->children)) {
+ struct clk_core *child;
+ struct hlist_node *t;
+
+ /* Reparent all children to the orphan list. */
+ hlist_for_each_entry_safe(child, t, &clk->core->children,
+ child_node)
+ clk_core_set_parent(child, NULL);
+ }
+
+ hlist_del_init(&clk->core->child_node);
+
+ if (clk->core->prepare_count)
+ pr_warn("%s: unregistering prepared clock: %s\n",
+ __func__, clk->core->name);
+ kref_put(&clk->core->ref, __clk_release);
+
+ clk_prepare_unlock();
+}
EXPORT_SYMBOL_GPL(clk_unregister);
static void devm_clk_release(struct device *dev, void *res)
{
- clk_unregister(res);
+ clk_unregister(*(struct clk **)res);
}
/**
struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw)
{
struct clk *clk;
- int ret;
+ struct clk **clkp;
- clk = devres_alloc(devm_clk_release, sizeof(*clk), GFP_KERNEL);
- if (!clk)
+ clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL);
+ if (!clkp)
return ERR_PTR(-ENOMEM);
- ret = _clk_register(dev, hw, clk);
- if (!ret) {
- devres_add(dev, clk);
+ clk = clk_register(dev, hw);
+ if (!IS_ERR(clk)) {
+ *clkp = clk;
+ devres_add(dev, clkp);
} else {
- devres_free(clk);
- clk = ERR_PTR(ret);
+ devres_free(clkp);
}
return clk;
}
EXPORT_SYMBOL_GPL(devm_clk_unregister);
+/*
+ * clkdev helpers
+ */
+int __clk_get(struct clk *clk)
+{
+ struct clk_core *core = !clk ? NULL : clk->core;
+
+ if (core) {
+ if (!try_module_get(core->owner))
+ return 0;
+
+ kref_get(&core->ref);
+ }
+ return 1;
+}
+
+void __clk_put(struct clk *clk)
+{
+ unsigned long rate;
+ struct module *owner;
+
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_prepare_lock();
+
+ hlist_del(&clk->clks_node);
+
+ rate = clk->core->req_rate;
+ if (!rate)
+ rate = clk->core->rate;
+
+ if (clk->min_rate > rate || clk->max_rate < rate)
+ clk_core_set_rate_nolock(clk->core, rate);
+
+ owner = clk->core->owner;
+ kref_put(&clk->core->ref, __clk_release);
+
+ clk_prepare_unlock();
+
+ module_put(owner);
+
+ kfree(clk);
+}
+
/*** clk rate change notifiers ***/
/**
* re-enter into the clk framework by calling any top-level clk APIs;
* this will cause a nested prepare_lock mutex.
*
- * Pre-change notifier callbacks will be passed the current, pre-change
- * rate of the clk via struct clk_notifier_data.old_rate. The new,
- * post-change rate of the clk is passed via struct
- * clk_notifier_data.new_rate.
- *
- * Post-change notifiers will pass the now-current, post-change rate of
- * the clk in both struct clk_notifier_data.old_rate and struct
+ * In all notification cases cases (pre, post and abort rate change) the
+ * original clock rate is passed to the callback via struct
+ * clk_notifier_data.old_rate and the new frequency is passed via struct
* clk_notifier_data.new_rate.
*
- * Abort-change notifiers are effectively the opposite of pre-change
- * notifiers: the original pre-change clk rate is passed in via struct
- * clk_notifier_data.new_rate and the failed post-change rate is passed
- * in via struct clk_notifier_data.old_rate.
- *
* clk_notifier_register() must be called from non-atomic context.
* Returns -EINVAL if called with null arguments, -ENOMEM upon
* allocation failure; otherwise, passes along the return value of
ret = srcu_notifier_chain_register(&cn->notifier_head, nb);
- clk->notifier_count++;
+ clk->core->notifier_count++;
out:
clk_prepare_unlock();
if (cn->clk == clk) {
ret = srcu_notifier_chain_unregister(&cn->notifier_head, nb);
- clk->notifier_count--;
+ clk->core->notifier_count--;
/* XXX the notifier code should handle this better */
if (!cn->notifier_head.head) {
void *data;
};
-extern struct of_device_id __clk_of_table[];
-
static const struct of_device_id __clk_of_table_sentinel
__used __section(__clk_of_table_end);
static LIST_HEAD(of_clk_providers);
-static DEFINE_MUTEX(of_clk_lock);
+static DEFINE_MUTEX(of_clk_mutex);
struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
void *data)
unsigned int idx = clkspec->args[0];
if (idx >= clk_data->clk_num) {
- pr_err("%s: invalid clock index %d\n", __func__, idx);
+ pr_err("%s: invalid clock index %u\n", __func__, idx);
return ERR_PTR(-EINVAL);
}
void *data)
{
struct of_clk_provider *cp;
+ int ret;
cp = kzalloc(sizeof(struct of_clk_provider), GFP_KERNEL);
if (!cp)
cp->data = data;
cp->get = clk_src_get;
- mutex_lock(&of_clk_lock);
+ mutex_lock(&of_clk_mutex);
list_add(&cp->link, &of_clk_providers);
- mutex_unlock(&of_clk_lock);
+ mutex_unlock(&of_clk_mutex);
pr_debug("Added clock from %s\n", np->full_name);
- return 0;
+ ret = of_clk_set_defaults(np, true);
+ if (ret < 0)
+ of_clk_del_provider(np);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(of_clk_add_provider);
{
struct of_clk_provider *cp;
- mutex_lock(&of_clk_lock);
+ mutex_lock(&of_clk_mutex);
list_for_each_entry(cp, &of_clk_providers, link) {
if (cp->node == np) {
list_del(&cp->link);
break;
}
}
- mutex_unlock(&of_clk_lock);
+ mutex_unlock(&of_clk_mutex);
}
EXPORT_SYMBOL_GPL(of_clk_del_provider);
-struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
+struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
+ const char *dev_id, const char *con_id,
+ bool with_orphans)
{
struct of_clk_provider *provider;
- struct clk *clk = ERR_PTR(-ENOENT);
+ struct clk *clk = ERR_PTR(-EPROBE_DEFER);
+
+ if (!clkspec)
+ return ERR_PTR(-EINVAL);
/* Check if we have such a provider in our array */
- mutex_lock(&of_clk_lock);
+ mutex_lock(&of_clk_mutex);
list_for_each_entry(provider, &of_clk_providers, link) {
if (provider->node == clkspec->np)
clk = provider->get(clkspec, provider->data);
- if (!IS_ERR(clk))
+ if (!IS_ERR(clk)) {
+ clk = __clk_create_clk(__clk_get_hw(clk), dev_id,
+ con_id, with_orphans);
+
+ if (!IS_ERR(clk) && !__clk_get(clk)) {
+ __clk_free_clk(clk);
+ clk = ERR_PTR(-ENOENT);
+ }
+
break;
+ }
}
- mutex_unlock(&of_clk_lock);
+ mutex_unlock(&of_clk_mutex);
return clk;
}
+/**
+ * of_clk_get_from_provider() - Lookup a clock from a clock provider
+ * @clkspec: pointer to a clock specifier data structure
+ *
+ * This function looks up a struct clk from the registered list of clock
+ * providers, an input is a clock specifier data structure as returned
+ * from the of_parse_phandle_with_args() function call.
+ */
+struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
+{
+ return __of_clk_get_from_provider(clkspec, NULL, __func__, false);
+}
+
+/**
+ * of_clk_get_from_provider_with_orphans() - Lookup clock from a clock provider
+ * @clkspec: pointer to a clock specifier data structure
+ *
+ * This function looks up a struct clk from the registered list of clock
+ * providers, an input is a clock specifier data structure as returned
+ * from the of_parse_phandle_with_args() function call.
+ *
+ * The difference to of_clk_get_from_provider() is that this function will
+ * also successfully lookup orphan-clocks, as it in some cases may be
+ * necessary to access such orphan-clocks as well.
+ */
+struct clk *
+of_clk_get_from_provider_with_orphans(struct of_phandle_args *clkspec)
+{
+ return __of_clk_get_from_provider(clkspec, NULL, __func__, true);
+}
+
+int of_clk_get_parent_count(struct device_node *np)
+{
+ return of_count_phandle_with_args(np, "clocks", "#clock-cells");
+}
+EXPORT_SYMBOL_GPL(of_clk_get_parent_count);
+
const char *of_clk_get_parent_name(struct device_node *np, int index)
{
struct of_phandle_args clkspec;
+ struct property *prop;
const char *clk_name;
+ const __be32 *vp;
+ u32 pv;
int rc;
+ int count;
+ struct clk *clk;
if (index < 0)
return NULL;
if (rc)
return NULL;
+ index = clkspec.args_count ? clkspec.args[0] : 0;
+ count = 0;
+
+ /* if there is an indices property, use it to transfer the index
+ * specified into an array offset for the clock-output-names property.
+ */
+ of_property_for_each_u32(clkspec.np, "clock-indices", prop, vp, pv) {
+ if (index == pv) {
+ index = count;
+ break;
+ }
+ count++;
+ }
+
if (of_property_read_string_index(clkspec.np, "clock-output-names",
- clkspec.args_count ? clkspec.args[0] : 0,
- &clk_name) < 0)
- clk_name = clkspec.np->name;
+ index,
+ &clk_name) < 0) {
+ /*
+ * Best effort to get the name if the clock has been
+ * registered with the framework. If the clock isn't
+ * registered, we return the node name as the name of
+ * the clock as long as #clock-cells = 0.
+ */
+ clk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(clk)) {
+ if (clkspec.args_count == 0)
+ clk_name = clkspec.np->name;
+ else
+ clk_name = NULL;
+ } else {
+ clk_name = __clk_get_name(clk);
+ clk_put(clk);
+ }
+ }
+
of_node_put(clkspec.np);
return clk_name;
}
EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
+/**
+ * of_clk_parent_fill() - Fill @parents with names of @np's parents and return
+ * number of parents
+ * @np: Device node pointer associated with clock provider
+ * @parents: pointer to char array that hold the parents' names
+ * @size: size of the @parents array
+ *
+ * Return: number of parents for the clock node.
+ */
+int of_clk_parent_fill(struct device_node *np, const char **parents,
+ unsigned int size)
+{
+ unsigned int i = 0;
+
+ while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
+ i++;
+
+ return i;
+}
+EXPORT_SYMBOL_GPL(of_clk_parent_fill);
+
+struct clock_provider {
+ of_clk_init_cb_t clk_init_cb;
+ struct device_node *np;
+ struct list_head node;
+};
+
+/*
+ * This function looks for a parent clock. If there is one, then it
+ * checks that the provider for this parent clock was initialized, in
+ * this case the parent clock will be ready.
+ */
+static int parent_ready(struct device_node *np)
+{
+ int i = 0;
+
+ while (true) {
+ struct clk *clk = of_clk_get(np, i);
+
+ /* this parent is ready we can check the next one */
+ if (!IS_ERR(clk)) {
+ clk_put(clk);
+ i++;
+ continue;
+ }
+
+ /* at least one parent is not ready, we exit now */
+ if (PTR_ERR(clk) == -EPROBE_DEFER)
+ return 0;
+
+ /*
+ * Here we make assumption that the device tree is
+ * written correctly. So an error means that there is
+ * no more parent. As we didn't exit yet, then the
+ * previous parent are ready. If there is no clock
+ * parent, no need to wait for them, then we can
+ * consider their absence as being ready
+ */
+ return 1;
+ }
+}
+
/**
* of_clk_init() - Scan and init clock providers from the DT
* @matches: array of compatible values and init functions for providers.
*
- * This function scans the device tree for matching clock providers and
- * calls their initialization functions
+ * This function scans the device tree for matching clock providers
+ * and calls their initialization functions. It also does it by trying
+ * to follow the dependencies.
*/
void __init of_clk_init(const struct of_device_id *matches)
{
+ const struct of_device_id *match;
struct device_node *np;
+ struct clock_provider *clk_provider, *next;
+ bool is_init_done;
+ bool force = false;
+ LIST_HEAD(clk_provider_list);
if (!matches)
- matches = __clk_of_table;
+ matches = &__clk_of_table;
+
+ /* First prepare the list of the clocks providers */
+ for_each_matching_node_and_match(np, matches, &match) {
+ struct clock_provider *parent;
+
+ parent = kzalloc(sizeof(*parent), GFP_KERNEL);
+ if (!parent) {
+ list_for_each_entry_safe(clk_provider, next,
+ &clk_provider_list, node) {
+ list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
+ kfree(clk_provider);
+ }
+ of_node_put(np);
+ return;
+ }
+
+ parent->clk_init_cb = match->data;
+ parent->np = of_node_get(np);
+ list_add_tail(&parent->node, &clk_provider_list);
+ }
+
+ while (!list_empty(&clk_provider_list)) {
+ is_init_done = false;
+ list_for_each_entry_safe(clk_provider, next,
+ &clk_provider_list, node) {
+ if (force || parent_ready(clk_provider->np)) {
+
+ clk_provider->clk_init_cb(clk_provider->np);
+ of_clk_set_defaults(clk_provider->np, true);
+
+ list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
+ kfree(clk_provider);
+ is_init_done = true;
+ }
+ }
- for_each_matching_node(np, matches) {
- const struct of_device_id *match = of_match_node(matches, np);
- of_clk_init_cb_t clk_init_cb = match->data;
- clk_init_cb(np);
+ /*
+ * We didn't manage to initialize any of the
+ * remaining providers during the last loop, so now we
+ * initialize all the remaining ones unconditionally
+ * in case the clock parent was not mandatory
+ */
+ if (!is_init_done)
+ force = true;
}
}
#endif
projects / firefly-linux-kernel-4.4.55.git / blobdiff