return now <= rate && now > best;
}
+ static void clk_core_init_rate_req(struct clk_core * const core,
+ struct clk_rate_request *req,
+ unsigned long rate);
+
+ static int clk_core_round_rate_nolock(struct clk_core *core,
+ struct clk_rate_request *req);
+
+ static bool clk_core_has_parent(struct clk_core *core, const struct clk_core *parent)
+ {
+ struct clk_core *tmp;
+ unsigned int i;
+
+ /* Optimize for the case where the parent is already the parent. */
+ if (core->parent == parent)
+ return true;
+
+ for (i = 0; i < core->num_parents; i++) {
+ tmp = clk_core_get_parent_by_index(core, i);
+ if (!tmp)
+ continue;
+
+ if (tmp == parent)
+ return true;
+ }
+
+ return false;
+ }
+
+ static void
+ clk_core_forward_rate_req(struct clk_core *core,
+ const struct clk_rate_request *old_req,
+ struct clk_core *parent,
+ struct clk_rate_request *req,
+ unsigned long parent_rate)
+ {
+ if (WARN_ON(!clk_core_has_parent(core, parent)))
+ return;
+
+ clk_core_init_rate_req(parent, req, parent_rate);
+
+ if (req->min_rate < old_req->min_rate)
+ req->min_rate = old_req->min_rate;
+
+ if (req->max_rate > old_req->max_rate)
+ req->max_rate = old_req->max_rate;
+ }
+
int clk_mux_determine_rate_flags(struct clk_hw *hw,
struct clk_rate_request *req,
unsigned long flags)
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);
+ struct clk_rate_request parent_req;
+
+ if (!parent) {
+ req->rate = 0;
+ return 0;
+ }
+
+ clk_core_forward_rate_req(core, req, parent, &parent_req, req->rate);
+ ret = clk_core_round_rate_nolock(parent, &parent_req);
if (ret)
return ret;
/* find the parent that can provide the fastest rate <= rate */
num_parents = core->num_parents;
for (i = 0; i < num_parents; i++) {
+ unsigned long parent_rate;
+
parent = clk_core_get_parent_by_index(core, i);
if (!parent)
continue;
if (core->flags & CLK_SET_RATE_PARENT) {
- parent_req = *req;
- ret = __clk_determine_rate(parent->hw, &parent_req);
+ struct clk_rate_request parent_req;
+
+ clk_core_forward_rate_req(core, req, parent, &parent_req, req->rate);
+ ret = clk_core_round_rate_nolock(parent, &parent_req);
if (ret)
continue;
+
+ parent_rate = parent_req.rate;
} else {
- parent_req.rate = clk_core_get_rate_nolock(parent);
+ parent_rate = clk_core_get_rate_nolock(parent);
}
- if (mux_is_better_rate(req->rate, parent_req.rate,
+ if (mux_is_better_rate(req->rate, parent_rate,
best, flags)) {
best_parent = parent;
- best = parent_req.rate;
+ best = parent_rate;
}
}
*max_rate = min(*max_rate, clk_user->max_rate);
}
+ /*
+ * clk_hw_get_rate_range() - returns the clock rate range for a hw clk
+ * @hw: the hw clk we want to get the range from
+ * @min_rate: pointer to the variable that will hold the minimum
+ * @max_rate: pointer to the variable that will hold the maximum
+ *
+ * Fills the @min_rate and @max_rate variables with the minimum and
+ * maximum that clock can reach.
+ */
+ void clk_hw_get_rate_range(struct clk_hw *hw, unsigned long *min_rate,
+ unsigned long *max_rate)
+ {
+ clk_core_get_boundaries(hw->core, min_rate, max_rate);
+ }
+ EXPORT_SYMBOL_GPL(clk_hw_get_rate_range);
+
static bool clk_core_check_boundaries(struct clk_core *core,
unsigned long min_rate,
unsigned long max_rate)
if (core->ops->unprepare)
core->ops->unprepare(core->hw);
- clk_pm_runtime_put(core);
-
trace_clk_unprepare_complete(core);
clk_core_unprepare(core->parent);
+ clk_pm_runtime_put(core);
}
static void clk_core_unprepare_lock(struct clk_core *core)
if (!core)
return 0;
- req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+ /*
+ * Some clock providers hand-craft their clk_rate_requests and
+ * might not fill min_rate and max_rate.
+ *
+ * If it's the case, clamping the rate is equivalent to setting
+ * the rate to 0 which is bad. Skip the clamping but complain so
+ * that it gets fixed, hopefully.
+ */
+ if (!req->min_rate && !req->max_rate)
+ pr_warn("%s: %s: clk_rate_request has initialized min or max rate.\n",
+ __func__, core->name);
+ else
+ req->rate = clamp(req->rate, req->min_rate, req->max_rate);
/*
* At this point, core protection will be disabled
}
static void clk_core_init_rate_req(struct clk_core * const core,
- struct clk_rate_request *req)
+ struct clk_rate_request *req,
+ unsigned long rate)
{
struct clk_core *parent;
if (WARN_ON(!core || !req))
return;
+ memset(req, 0, sizeof(*req));
+
+ req->rate = rate;
+ clk_core_get_boundaries(core, &req->min_rate, &req->max_rate);
+
parent = core->parent;
if (parent) {
req->best_parent_hw = parent->hw;
}
}
+ /**
+ * clk_hw_init_rate_request - Initializes a clk_rate_request
+ * @hw: the clk for which we want to submit a rate request
+ * @req: the clk_rate_request structure we want to initialise
+ * @rate: the rate which is to be requested
+ *
+ * Initializes a clk_rate_request structure to submit to
+ * __clk_determine_rate() or similar functions.
+ */
+ void clk_hw_init_rate_request(const struct clk_hw *hw,
+ struct clk_rate_request *req,
+ unsigned long rate)
+ {
+ if (WARN_ON(!hw || !req))
+ return;
+
+ clk_core_init_rate_req(hw->core, req, rate);
+ }
+ EXPORT_SYMBOL_GPL(clk_hw_init_rate_request);
+
+ /**
+ * clk_hw_forward_rate_request - Forwards a clk_rate_request to a clock's parent
+ * @hw: the original clock that got the rate request
+ * @old_req: the original clk_rate_request structure we want to forward
+ * @parent: the clk we want to forward @old_req to
+ * @req: the clk_rate_request structure we want to initialise
+ * @parent_rate: The rate which is to be requested to @parent
+ *
+ * Initializes a clk_rate_request structure to submit to a clock parent
+ * in __clk_determine_rate() or similar functions.
+ */
+ void clk_hw_forward_rate_request(const struct clk_hw *hw,
+ const struct clk_rate_request *old_req,
+ const struct clk_hw *parent,
+ struct clk_rate_request *req,
+ unsigned long parent_rate)
+ {
+ if (WARN_ON(!hw || !old_req || !parent || !req))
+ return;
+
+ clk_core_forward_rate_req(hw->core, old_req,
+ parent->core, req,
+ parent_rate);
+ }
+
static bool clk_core_can_round(struct clk_core * const core)
{
return core->ops->determine_rate || core->ops->round_rate;
static int clk_core_round_rate_nolock(struct clk_core *core,
struct clk_rate_request *req)
{
+ int ret;
+
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);
+
+ if (core->flags & CLK_SET_RATE_PARENT) {
+ struct clk_rate_request parent_req;
+
+ clk_core_forward_rate_req(core, req, core->parent, &parent_req, req->rate);
+ ret = clk_core_round_rate_nolock(core->parent, &parent_req);
+ if (ret)
+ return ret;
+
+ req->best_parent_rate = parent_req.rate;
+ req->rate = parent_req.rate;
+
+ return 0;
+ }
req->rate = core->rate;
return 0;
int ret;
struct clk_rate_request req;
- clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate);
- req.rate = rate;
+ clk_core_init_rate_req(hw->core, &req, rate);
ret = clk_core_round_rate_nolock(hw->core, &req);
if (ret)
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;
+ clk_core_init_rate_req(clk->core, &req, rate);
ret = clk_core_round_rate_nolock(clk->core, &req);
/**
* __clk_recalc_rates
* @core: first clk in the subtree
+ * @update_req: Whether req_rate should be updated with the new rate
* @msg: notification type (see include/linux/clk.h)
*
* Walks the subtree of clks starting with clk and recalculates rates as it
* clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
* if necessary.
*/
- static void __clk_recalc_rates(struct clk_core *core, unsigned long msg)
+ static void __clk_recalc_rates(struct clk_core *core, bool update_req,
+ unsigned long msg)
{
unsigned long old_rate;
unsigned long parent_rate = 0;
parent_rate = core->parent->rate;
core->rate = clk_recalc(core, parent_rate);
+ if (update_req)
+ core->req_rate = core->rate;
/*
* ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
__clk_notify(core, msg, old_rate, core->rate);
hlist_for_each_entry(child, &core->children, child_node)
- __clk_recalc_rates(child, msg);
+ __clk_recalc_rates(child, update_req, msg);
}
static unsigned long clk_core_get_rate_recalc(struct clk_core *core)
{
if (core && (core->flags & CLK_GET_RATE_NOCACHE))
- __clk_recalc_rates(core, 0);
+ __clk_recalc_rates(core, false, 0);
return clk_core_get_rate_nolock(core);
}
* @clk: the clk whose rate is being returned
*
* Simply returns the cached rate of the clk, unless CLK_GET_RATE_NOCACHE flag
- * is set, which means a recalc_rate will be issued.
- * If clk is NULL then returns 0.
+ * is set, which means a recalc_rate will be issued. Can be called regardless of
+ * the clock enabledness. If clk is NULL, or if an error occurred, then returns
+ * 0.
*/
unsigned long clk_get_rate(struct clk *clk)
{
flags = clk_enable_lock();
clk_reparent(core, old_parent);
clk_enable_unlock(flags);
+
__clk_set_parent_after(core, old_parent, parent);
return ret;
if (clk_core_can_round(core)) {
struct clk_rate_request req;
- req.rate = rate;
- req.min_rate = min_rate;
- req.max_rate = max_rate;
-
- clk_core_init_rate_req(core, &req);
+ clk_core_init_rate_req(core, &req, rate);
ret = clk_core_determine_round_nolock(core, &req);
if (ret < 0)
if (cnt < 0)
return cnt;
- clk_core_get_boundaries(core, &req.min_rate, &req.max_rate);
- req.rate = req_rate;
+ clk_core_init_rate_req(core, &req, req_rate);
ret = clk_core_round_rate_nolock(core, &req);
}
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
- * @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)
+ static int clk_set_rate_range_nolock(struct clk *clk,
+ unsigned long min,
+ unsigned long max)
{
int ret = 0;
unsigned long old_min, old_max, rate;
+ lockdep_assert_held(&prepare_lock);
+
if (!clk)
return 0;
return -EINVAL;
}
- clk_prepare_lock();
-
if (clk->exclusive_count)
clk_core_rate_unprotect(clk->core);
goto out;
}
+ rate = clk->core->req_rate;
+ if (clk->core->flags & CLK_GET_RATE_NOCACHE)
+ rate = clk_core_get_rate_recalc(clk->core);
+
/*
* Since the boundaries have been changed, let's give the
* opportunity to the provider to adjust the clock rate based on
* - the determine_rate() callback does not really check for
* this corner case when determining the rate
*/
- rate = clamp(clk->core->req_rate, min, max);
+ rate = clamp(rate, min, max);
ret = clk_core_set_rate_nolock(clk->core, rate);
if (ret) {
/* rollback the changes */
if (clk->exclusive_count)
clk_core_rate_protect(clk->core);
+ return ret;
+ }
+
+ /**
+ * 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
+ *
+ * Return: 0 for success or negative errno on failure.
+ */
+ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
+ {
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ clk_prepare_lock();
+
+ ret = clk_set_rate_range_nolock(clk, min, max);
+
clk_prepare_unlock();
return ret;
{
clk_reparent(core, new_parent);
__clk_recalc_accuracies(core);
- __clk_recalc_rates(core, POST_RATE_CHANGE);
+ __clk_recalc_rates(core, true, POST_RATE_CHANGE);
}
void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
*
* Returns true if @parent is a possible parent for @clk, false otherwise.
*/
- bool clk_has_parent(struct clk *clk, struct clk *parent)
+ bool clk_has_parent(const struct clk *clk, const struct clk *parent)
{
- struct clk_core *core, *parent_core;
- int i;
-
/* NULL clocks should be nops, so return success if either is NULL. */
if (!clk || !parent)
return true;
- core = clk->core;
- parent_core = parent->core;
-
- /* 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->parents[i].name, parent_core->name))
- return true;
-
- return false;
+ return clk_core_has_parent(clk->core, parent->core);
}
EXPORT_SYMBOL_GPL(clk_has_parent);
/* propagate rate an accuracy recalculation accordingly */
if (ret) {
- __clk_recalc_rates(core, ABORT_RATE_CHANGE);
+ __clk_recalc_rates(core, true, ABORT_RATE_CHANGE);
} else {
- __clk_recalc_rates(core, POST_RATE_CHANGE);
+ __clk_recalc_rates(core, true, POST_RATE_CHANGE);
__clk_recalc_accuracies(core);
}
__clk_set_parent_before(orphan, parent);
__clk_set_parent_after(orphan, parent, NULL);
__clk_recalc_accuracies(orphan);
- __clk_recalc_rates(orphan, 0);
+ __clk_recalc_rates(orphan, true, 0);
/*
* __clk_init_parent() will set the initial req_rate to
}
hlist_del(&clk->clks_node);
- if (clk->min_rate > clk->core->req_rate ||
- clk->max_rate < clk->core->req_rate)
- clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+
+ /* If we had any boundaries on that clock, let's drop them. */
+ if (clk->min_rate > 0 || clk->max_rate < ULONG_MAX)
+ clk_set_rate_range_nolock(clk, 0, ULONG_MAX);
owner = clk->core->owner;
kref_put(&clk->core->ref, __clk_release);
projects / J-linux.git / commitdiff