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path: root/drivers/clk/clk.c
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-rw-r--r--drivers/clk/clk.c615
1 files changed, 518 insertions, 97 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b221d80cc7ba..98f89ccc46a7 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -24,6 +24,7 @@
#include <linux/pm_runtime.h>
#include <linux/sched.h>
#include <linux/clkdev.h>
+#include <linux/stringify.h>
#include "clk.h"
@@ -62,6 +63,7 @@ struct clk_core {
bool orphan;
unsigned int enable_count;
unsigned int prepare_count;
+ unsigned int protect_count;
unsigned long min_rate;
unsigned long max_rate;
unsigned long accuracy;
@@ -86,6 +88,7 @@ struct clk {
const char *con_id;
unsigned long min_rate;
unsigned long max_rate;
+ unsigned int exclusive_count;
struct hlist_node clks_node;
};
@@ -178,6 +181,11 @@ static void clk_enable_unlock(unsigned long flags)
spin_unlock_irqrestore(&enable_lock, flags);
}
+static bool clk_core_rate_is_protected(struct clk_core *core)
+{
+ return core->protect_count;
+}
+
static bool clk_core_is_prepared(struct clk_core *core)
{
bool ret = false;
@@ -389,6 +397,11 @@ bool clk_hw_is_prepared(const struct clk_hw *hw)
return clk_core_is_prepared(hw->core);
}
+bool clk_hw_rate_is_protected(const struct clk_hw *hw)
+{
+ return clk_core_rate_is_protected(hw->core);
+}
+
bool clk_hw_is_enabled(const struct clk_hw *hw)
{
return clk_core_is_enabled(hw->core);
@@ -527,6 +540,139 @@ EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
/*** clk api ***/
+static void clk_core_rate_unprotect(struct clk_core *core)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (WARN_ON(core->protect_count == 0))
+ return;
+
+ if (--core->protect_count > 0)
+ return;
+
+ clk_core_rate_unprotect(core->parent);
+}
+
+static int clk_core_rate_nuke_protect(struct clk_core *core)
+{
+ int ret;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return -EINVAL;
+
+ if (core->protect_count == 0)
+ return 0;
+
+ ret = core->protect_count;
+ core->protect_count = 1;
+ clk_core_rate_unprotect(core);
+
+ return ret;
+}
+
+/**
+ * clk_rate_exclusive_put - release exclusivity over clock rate control
+ * @clk: the clk over which the exclusivity is released
+ *
+ * clk_rate_exclusive_put() completes a critical section during which a clock
+ * consumer cannot tolerate any other consumer making any operation on the
+ * clock which could result in a rate change or rate glitch. Exclusive clocks
+ * cannot have their rate changed, either directly or indirectly due to changes
+ * further up the parent chain of clocks. As a result, clocks up parent chain
+ * also get under exclusive control of the calling consumer.
+ *
+ * If exlusivity is claimed more than once on clock, even by the same consumer,
+ * the rate effectively gets locked as exclusivity can't be preempted.
+ *
+ * Calls to clk_rate_exclusive_put() must be balanced with calls to
+ * clk_rate_exclusive_get(). Calls to this function may sleep, and do not return
+ * error status.
+ */
+void clk_rate_exclusive_put(struct clk *clk)
+{
+ if (!clk)
+ return;
+
+ clk_prepare_lock();
+
+ /*
+ * if there is something wrong with this consumer protect count, stop
+ * here before messing with the provider
+ */
+ if (WARN_ON(clk->exclusive_count <= 0))
+ goto out;
+
+ clk_core_rate_unprotect(clk->core);
+ clk->exclusive_count--;
+out:
+ clk_prepare_unlock();
+}
+EXPORT_SYMBOL_GPL(clk_rate_exclusive_put);
+
+static void clk_core_rate_protect(struct clk_core *core)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (core->protect_count == 0)
+ clk_core_rate_protect(core->parent);
+
+ core->protect_count++;
+}
+
+static void clk_core_rate_restore_protect(struct clk_core *core, int count)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (count == 0)
+ return;
+
+ clk_core_rate_protect(core);
+ core->protect_count = count;
+}
+
+/**
+ * clk_rate_exclusive_get - get exclusivity over the clk rate control
+ * @clk: the clk over which the exclusity of rate control is requested
+ *
+ * clk_rate_exlusive_get() begins a critical section during which a clock
+ * consumer cannot tolerate any other consumer making any operation on the
+ * clock which could result in a rate change or rate glitch. Exclusive clocks
+ * cannot have their rate changed, either directly or indirectly due to changes
+ * further up the parent chain of clocks. As a result, clocks up parent chain
+ * also get under exclusive control of the calling consumer.
+ *
+ * If exlusivity is claimed more than once on clock, even by the same consumer,
+ * the rate effectively gets locked as exclusivity can't be preempted.
+ *
+ * Calls to clk_rate_exclusive_get() should be balanced with calls to
+ * clk_rate_exclusive_put(). Calls to this function may sleep.
+ * Returns 0 on success, -EERROR otherwise
+ */
+int clk_rate_exclusive_get(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ clk_prepare_lock();
+ clk_core_rate_protect(clk->core);
+ clk->exclusive_count++;
+ clk_prepare_unlock();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_rate_exclusive_get);
+
static void clk_core_unprepare(struct clk_core *core)
{
lockdep_assert_held(&prepare_lock);
@@ -913,10 +1059,9 @@ static int clk_disable_unused(void)
}
late_initcall_sync(clk_disable_unused);
-static int clk_core_round_rate_nolock(struct clk_core *core,
- struct clk_rate_request *req)
+static int clk_core_determine_round_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
{
- struct clk_core *parent;
long rate;
lockdep_assert_held(&prepare_lock);
@@ -924,16 +1069,15 @@ static int clk_core_round_rate_nolock(struct clk_core *core,
if (!core)
return 0;
- 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 (core->ops->determine_rate) {
+ /*
+ * At this point, core protection will be disabled if
+ * - if the provider is not protected at all
+ * - if the calling consumer is the only one which has exclusivity
+ * over the provider
+ */
+ if (clk_core_rate_is_protected(core)) {
+ req->rate = core->rate;
+ } else 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,
@@ -942,15 +1086,58 @@ static int clk_core_round_rate_nolock(struct clk_core *core,
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 -EINVAL;
}
return 0;
}
+static void clk_core_init_rate_req(struct clk_core * const core,
+ struct clk_rate_request *req)
+{
+ struct clk_core *parent;
+
+ if (WARN_ON(!core || !req))
+ return;
+
+ 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;
+ }
+}
+
+static bool clk_core_can_round(struct clk_core * const core)
+{
+ if (core->ops->determine_rate || core->ops->round_rate)
+ return true;
+
+ return false;
+}
+
+static int clk_core_round_rate_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ clk_core_init_rate_req(core, req);
+
+ if (clk_core_can_round(core))
+ return clk_core_determine_round_nolock(core, req);
+ else if (core->flags & CLK_SET_RATE_PARENT)
+ return clk_core_round_rate_nolock(core->parent, req);
+
+ req->rate = core->rate;
+ return 0;
+}
+
/**
* __clk_determine_rate - get the closest rate actually supported by a clock
* @hw: determine the rate of this clock
@@ -1004,10 +1191,17 @@ long clk_round_rate(struct clk *clk, unsigned long rate)
clk_prepare_lock();
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
req.rate = rate;
ret = clk_core_round_rate_nolock(clk->core, &req);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
clk_prepare_unlock();
if (ret)
@@ -1440,34 +1634,23 @@ static struct clk_core *clk_calc_new_rates(struct clk_core *core,
clk_core_get_boundaries(core, &min_rate, &max_rate);
/* find the closest rate and parent clk/rate */
- if (core->ops->determine_rate) {
+ if (clk_core_can_round(core)) {
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;
- }
- ret = core->ops->determine_rate(core->hw, &req);
+ clk_core_init_rate_req(core, &req);
+
+ ret = clk_core_determine_round_nolock(core, &req);
if (ret < 0)
return NULL;
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)) {
@@ -1572,6 +1755,9 @@ static void clk_change_rate(struct clk_core *core)
best_parent_rate = core->parent->rate;
}
+ if (clk_pm_runtime_get(core))
+ return;
+
if (core->flags & CLK_SET_RATE_UNGATE) {
unsigned long flags;
@@ -1642,27 +1828,62 @@ static void clk_change_rate(struct clk_core *core)
/* handle the new child who might not be in core->children yet */
if (core->new_child)
clk_change_rate(core->new_child);
+
+ clk_pm_runtime_put(core);
+}
+
+static unsigned long clk_core_req_round_rate_nolock(struct clk_core *core,
+ unsigned long req_rate)
+{
+ int ret, cnt;
+ struct clk_rate_request req;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ /* simulate what the rate would be if it could be freely set */
+ cnt = clk_core_rate_nuke_protect(core);
+ if (cnt < 0)
+ return cnt;
+
+ clk_core_get_boundaries(core, &req.min_rate, &req.max_rate);
+ req.rate = req_rate;
+
+ ret = clk_core_round_rate_nolock(core, &req);
+
+ /* restore the protection */
+ clk_core_rate_restore_protect(core, cnt);
+
+ return ret ? 0 : 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;
+ unsigned long rate;
int ret = 0;
if (!core)
return 0;
+ rate = clk_core_req_round_rate_nolock(core, req_rate);
+
/* bail early if nothing to do */
if (rate == clk_core_get_rate_nolock(core))
return 0;
+ /* fail on a direct rate set of a protected provider */
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
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);
+ top = clk_calc_new_rates(core, req_rate);
if (!top)
return -EINVAL;
@@ -1721,8 +1942,14 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
/* prevent racing with updates to the clock topology */
clk_prepare_lock();
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
clk_prepare_unlock();
return ret;
@@ -1730,6 +1957,53 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
EXPORT_SYMBOL_GPL(clk_set_rate);
/**
+ * clk_set_rate_exclusive - specify a new rate get exclusive control
+ * @clk: the clk whose rate is being changed
+ * @rate: the new rate for clk
+ *
+ * This is a combination of clk_set_rate() and clk_rate_exclusive_get()
+ * within a critical section
+ *
+ * This can be used initially to ensure that at least 1 consumer is
+ * statisfied when several consumers are competing for exclusivity over the
+ * same clock provider.
+ *
+ * The exclusivity is not applied if setting the rate failed.
+ *
+ * Calls to clk_rate_exclusive_get() should be balanced with calls to
+ * clk_rate_exclusive_put().
+ *
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int clk_set_rate_exclusive(struct clk *clk, unsigned long rate)
+{
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ /* prevent racing with updates to the clock topology */
+ clk_prepare_lock();
+
+ /*
+ * The temporary protection removal is not here, on purpose
+ * This function is meant to be used instead of clk_rate_protect,
+ * so before the consumer code path protect the clock provider
+ */
+
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (!ret) {
+ clk_core_rate_protect(clk->core);
+ clk->exclusive_count++;
+ }
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate_exclusive);
+
+/**
* clk_set_rate_range - set a rate range for a clock source
* @clk: clock source
* @min: desired minimum clock rate in Hz, inclusive
@@ -1740,6 +2014,7 @@ EXPORT_SYMBOL_GPL(clk_set_rate);
int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
{
int ret = 0;
+ unsigned long old_min, old_max, rate;
if (!clk)
return 0;
@@ -1753,12 +2028,46 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
clk_prepare_lock();
- if (min != clk->min_rate || max != clk->max_rate) {
- clk->min_rate = min;
- clk->max_rate = max;
- ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ /* Save the current values in case we need to rollback the change */
+ old_min = clk->min_rate;
+ old_max = clk->max_rate;
+ clk->min_rate = min;
+ clk->max_rate = max;
+
+ rate = clk_core_get_rate_nolock(clk->core);
+ if (rate < min || rate > max) {
+ /*
+ * FIXME:
+ * We are in bit of trouble here, current rate is outside the
+ * the requested range. We are going try to request appropriate
+ * range boundary but there is a catch. It may fail for the
+ * usual reason (clock broken, clock protected, etc) but also
+ * because:
+ * - round_rate() was not favorable and fell on the wrong
+ * side of the boundary
+ * - the determine_rate() callback does not really check for
+ * this corner case when determining the rate
+ */
+
+ if (rate < min)
+ rate = min;
+ else
+ rate = max;
+
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (ret) {
+ /* rollback the changes */
+ clk->min_rate = old_min;
+ clk->max_rate = old_max;
+ }
}
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
clk_prepare_unlock();
return ret;
@@ -1879,32 +2188,31 @@ bool clk_has_parent(struct clk *clk, struct clk *parent)
}
EXPORT_SYMBOL_GPL(clk_has_parent);
-static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
+static int clk_core_set_parent_nolock(struct clk_core *core,
+ struct clk_core *parent)
{
int ret = 0;
int p_index = 0;
unsigned long p_rate = 0;
+ lockdep_assert_held(&prepare_lock);
+
if (!core)
return 0;
- /* prevent racing with updates to the clock topology */
- clk_prepare_lock();
-
if (core->parent == parent)
- goto out;
+ return 0;
/* verify ops for for multi-parent clks */
- if ((core->num_parents > 1) && (!core->ops->set_parent)) {
- ret = -ENOSYS;
- goto out;
- }
+ if (core->num_parents > 1 && !core->ops->set_parent)
+ return -EPERM;
/* 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 ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count)
+ return -EBUSY;
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
/* try finding the new parent index */
if (parent) {
@@ -1912,15 +2220,14 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
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;
+ return p_index;
}
p_rate = parent->rate;
}
ret = clk_pm_runtime_get(core);
if (ret)
- goto out;
+ return ret;
/* propagate PRE_RATE_CHANGE notifications */
ret = __clk_speculate_rates(core, p_rate);
@@ -1942,8 +2249,6 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
runtime_put:
clk_pm_runtime_put(core);
-out:
- clk_prepare_unlock();
return ret;
}
@@ -1967,13 +2272,50 @@ out:
*/
int clk_set_parent(struct clk *clk, struct clk *parent)
{
+ int ret;
+
if (!clk)
return 0;
- return clk_core_set_parent(clk->core, parent ? parent->core : NULL);
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_parent_nolock(clk->core,
+ parent ? parent->core : NULL);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
}
EXPORT_SYMBOL_GPL(clk_set_parent);
+static int clk_core_set_phase_nolock(struct clk_core *core, int degrees)
+{
+ int ret = -EINVAL;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ trace_clk_set_phase(core, degrees);
+
+ if (core->ops->set_phase)
+ ret = core->ops->set_phase(core->hw, degrees);
+
+ trace_clk_set_phase_complete(core, degrees);
+
+ return ret;
+}
+
/**
* clk_set_phase - adjust the phase shift of a clock signal
* @clk: clock signal source
@@ -1996,7 +2338,7 @@ EXPORT_SYMBOL_GPL(clk_set_parent);
*/
int clk_set_phase(struct clk *clk, int degrees)
{
- int ret = -EINVAL;
+ int ret;
if (!clk)
return 0;
@@ -2008,15 +2350,13 @@ int clk_set_phase(struct clk *clk, int degrees)
clk_prepare_lock();
- trace_clk_set_phase(clk->core, degrees);
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
- if (clk->core->ops->set_phase)
- ret = clk->core->ops->set_phase(clk->core->hw, degrees);
+ ret = clk_core_set_phase_nolock(clk->core, degrees);
- trace_clk_set_phase_complete(clk->core, degrees);
-
- if (!ret)
- clk->core->phase = degrees;
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
clk_prepare_unlock();
@@ -2104,11 +2444,12 @@ static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
if (!c)
return;
- seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n",
+ seq_printf(s, "%*s%-*s %7d %8d %8d %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));
+ c->enable_count, c->prepare_count, c->protect_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,
@@ -2130,7 +2471,8 @@ 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, " enable prepare protect \n");
+ seq_puts(s, " clock count count count rate accuracy phase\n");
seq_puts(s, "----------------------------------------------------------------------------------------\n");
clk_prepare_lock();
@@ -2166,6 +2508,7 @@ static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
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, "\"protect_count\": %d,", c->protect_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));
@@ -2225,6 +2568,58 @@ static const struct file_operations clk_dump_fops = {
.release = single_release,
};
+static const struct {
+ unsigned long flag;
+ const char *name;
+} clk_flags[] = {
+#define ENTRY(f) { f, __stringify(f) }
+ ENTRY(CLK_SET_RATE_GATE),
+ ENTRY(CLK_SET_PARENT_GATE),
+ ENTRY(CLK_SET_RATE_PARENT),
+ ENTRY(CLK_IGNORE_UNUSED),
+ ENTRY(CLK_IS_BASIC),
+ ENTRY(CLK_GET_RATE_NOCACHE),
+ ENTRY(CLK_SET_RATE_NO_REPARENT),
+ ENTRY(CLK_GET_ACCURACY_NOCACHE),
+ ENTRY(CLK_RECALC_NEW_RATES),
+ ENTRY(CLK_SET_RATE_UNGATE),
+ ENTRY(CLK_IS_CRITICAL),
+ ENTRY(CLK_OPS_PARENT_ENABLE),
+#undef ENTRY
+};
+
+static int clk_flags_dump(struct seq_file *s, void *data)
+{
+ struct clk_core *core = s->private;
+ unsigned long flags = core->flags;
+ unsigned int i;
+
+ for (i = 0; flags && i < ARRAY_SIZE(clk_flags); i++) {
+ if (flags & clk_flags[i].flag) {
+ seq_printf(s, "%s\n", clk_flags[i].name);
+ flags &= ~clk_flags[i].flag;
+ }
+ }
+ if (flags) {
+ /* Unknown flags */
+ seq_printf(s, "0x%lx\n", flags);
+ }
+
+ return 0;
+}
+
+static int clk_flags_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_flags_dump, inode->i_private);
+}
+
+static const struct file_operations clk_flags_fops = {
+ .open = clk_flags_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static int possible_parents_dump(struct seq_file *s, void *data)
{
struct clk_core *core = s->private;
@@ -2266,43 +2661,46 @@ static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
core->dentry = d;
- d = debugfs_create_u32("clk_rate", S_IRUGO, core->dentry,
- (u32 *)&core->rate);
+ d = debugfs_create_ulong("clk_rate", 0444, core->dentry, &core->rate);
if (!d)
goto err_out;
- d = debugfs_create_u32("clk_accuracy", S_IRUGO, core->dentry,
- (u32 *)&core->accuracy);
+ d = debugfs_create_ulong("clk_accuracy", 0444, core->dentry,
+ &core->accuracy);
if (!d)
goto err_out;
- d = debugfs_create_u32("clk_phase", S_IRUGO, core->dentry,
- (u32 *)&core->phase);
+ d = debugfs_create_u32("clk_phase", 0444, core->dentry, &core->phase);
if (!d)
goto err_out;
- d = debugfs_create_x32("clk_flags", S_IRUGO, core->dentry,
- (u32 *)&core->flags);
+ d = debugfs_create_file("clk_flags", 0444, core->dentry, core,
+ &clk_flags_fops);
if (!d)
goto err_out;
- d = debugfs_create_u32("clk_prepare_count", S_IRUGO, core->dentry,
- (u32 *)&core->prepare_count);
+ d = debugfs_create_u32("clk_prepare_count", 0444, core->dentry,
+ &core->prepare_count);
if (!d)
goto err_out;
- d = debugfs_create_u32("clk_enable_count", S_IRUGO, core->dentry,
- (u32 *)&core->enable_count);
+ d = debugfs_create_u32("clk_enable_count", 0444, core->dentry,
+ &core->enable_count);
if (!d)
goto err_out;
- d = debugfs_create_u32("clk_notifier_count", S_IRUGO, core->dentry,
- (u32 *)&core->notifier_count);
+ d = debugfs_create_u32("clk_protect_count", 0444, core->dentry,
+ &core->protect_count);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_notifier_count", 0444, core->dentry,
+ &core->notifier_count);
if (!d)
goto err_out;
if (core->num_parents > 1) {
- d = debugfs_create_file("clk_possible_parents", S_IRUGO,
+ d = debugfs_create_file("clk_possible_parents", 0444,
core->dentry, core, &possible_parents_fops);
if (!d)
goto err_out;
@@ -2338,12 +2736,8 @@ static int clk_debug_register(struct clk_core *core)
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:
+ if (inited)
+ ret = clk_debug_create_one(core, rootdir);
mutex_unlock(&clk_debug_lock);
return ret;
@@ -2398,22 +2792,22 @@ static int __init clk_debug_init(void)
if (!rootdir)
return -ENOMEM;
- d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
+ d = debugfs_create_file("clk_summary", 0444, rootdir, &all_lists,
&clk_summary_fops);
if (!d)
return -ENOMEM;
- d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
+ d = debugfs_create_file("clk_dump", 0444, rootdir, &all_lists,
&clk_dump_fops);
if (!d)
return -ENOMEM;
- d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
+ d = debugfs_create_file("clk_orphan_summary", 0444, rootdir,
&orphan_list, &clk_summary_fops);
if (!d)
return -ENOMEM;
- d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
+ d = debugfs_create_file("clk_orphan_dump", 0444, rootdir,
&orphan_list, &clk_dump_fops);
if (!d)
return -ENOMEM;
@@ -2578,14 +2972,17 @@ static int __clk_core_init(struct clk_core *core)
*/
hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
struct clk_core *parent = __clk_init_parent(orphan);
+ unsigned long flags;
/*
* we could call __clk_set_parent, but that would result in a
* redundant call to the .set_rate op, if it exists
*/
if (parent) {
- __clk_set_parent_before(orphan, parent);
- __clk_set_parent_after(orphan, parent, NULL);
+ /* update the clk tree topology */
+ flags = clk_enable_lock();
+ clk_reparent(orphan, parent);
+ clk_enable_unlock(flags);
__clk_recalc_accuracies(orphan);
__clk_recalc_rates(orphan, 0);
}
@@ -2686,7 +3083,13 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
ret = -ENOMEM;
goto fail_name;
}
+
+ if (WARN_ON(!hw->init->ops)) {
+ ret = -EINVAL;
+ goto fail_ops;
+ }
core->ops = hw->init->ops;
+
if (dev && pm_runtime_enabled(dev))
core->dev = dev;
if (dev && dev->driver)
@@ -2748,6 +3151,7 @@ fail_parent_names_copy:
kfree_const(core->parent_names[i]);
kfree(core->parent_names);
fail_parent_names:
+fail_ops:
kfree_const(core->name);
fail_name:
kfree(core);
@@ -2859,7 +3263,7 @@ void clk_unregister(struct clk *clk)
/* 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);
+ clk_core_set_parent_nolock(child, NULL);
}
hlist_del_init(&clk->core->child_node);
@@ -2867,6 +3271,11 @@ void clk_unregister(struct clk *clk)
if (clk->core->prepare_count)
pr_warn("%s: unregistering prepared clock: %s\n",
__func__, clk->core->name);
+
+ if (clk->core->protect_count)
+ pr_warn("%s: unregistering protected clock: %s\n",
+ __func__, clk->core->name);
+
kref_put(&clk->core->ref, __clk_release);
unlock:
clk_prepare_unlock();
@@ -3025,6 +3434,18 @@ void __clk_put(struct clk *clk)
clk_prepare_lock();
+ /*
+ * Before calling clk_put, all calls to clk_rate_exclusive_get() from a
+ * given user should be balanced with calls to clk_rate_exclusive_put()
+ * and by that same consumer
+ */
+ if (WARN_ON(clk->exclusive_count)) {
+ /* We voiced our concern, let's sanitize the situation */
+ clk->core->protect_count -= (clk->exclusive_count - 1);
+ clk_core_rate_unprotect(clk->core);
+ clk->exclusive_count = 0;
+ }
+
hlist_del(&clk->clks_node);
if (clk->min_rate > clk->core->req_rate ||
clk->max_rate < clk->core->req_rate)
@@ -3561,7 +3982,7 @@ static int parent_ready(struct device_node *np)
* of_clk_detect_critical() - set CLK_IS_CRITICAL flag from Device Tree
* @np: Device node pointer associated with clock provider
* @index: clock index
- * @flags: pointer to clk_core->flags
+ * @flags: pointer to top-level framework flags
*
* Detects if the clock-critical property exists and, if so, sets the
* corresponding CLK_IS_CRITICAL flag.

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