diff options
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r-- | drivers/clk/clk.c | 349 |
1 files changed, 209 insertions, 140 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index ddb4b5410..0ebcf4497 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -9,6 +9,7 @@ * Standard functionality for the common clock API. See Documentation/clk.txt */ +#include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/clk/clk-conf.h> #include <linux/module.h> @@ -56,8 +57,11 @@ struct clk_core { 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; @@ -111,12 +115,14 @@ static void clk_prepare_unlock(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); @@ -129,12 +135,15 @@ static unsigned long clk_enable_lock(void) } 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); } @@ -269,27 +278,29 @@ const char *__clk_get_name(struct clk *clk) } EXPORT_SYMBOL_GPL(__clk_get_name); +const char *clk_hw_get_name(const struct clk_hw *hw) +{ + return hw->core->name; +} +EXPORT_SYMBOL_GPL(clk_hw_get_name); + struct clk_hw *__clk_get_hw(struct clk *clk) { return !clk ? NULL : clk->core->hw; } EXPORT_SYMBOL_GPL(__clk_get_hw); -u8 __clk_get_num_parents(struct clk *clk) +unsigned int clk_hw_get_num_parents(const struct clk_hw *hw) { - return !clk ? 0 : clk->core->num_parents; + return hw->core->num_parents; } -EXPORT_SYMBOL_GPL(__clk_get_num_parents); +EXPORT_SYMBOL_GPL(clk_hw_get_num_parents); -struct clk *__clk_get_parent(struct clk *clk) +struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw) { - if (!clk) - return NULL; - - /* TODO: Create a per-user clk and change callers to call clk_put */ - return !clk->core->parent ? NULL : clk->core->parent->hw->clk; + return hw->core->parent ? hw->core->parent->hw : NULL; } -EXPORT_SYMBOL_GPL(__clk_get_parent); +EXPORT_SYMBOL_GPL(clk_hw_get_parent); static struct clk_core *__clk_lookup_subtree(const char *name, struct clk_core *core) @@ -348,18 +359,16 @@ static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core, return core->parents[index]; } -struct clk *clk_get_parent_by_index(struct clk *clk, u8 index) +struct clk_hw * +clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index) { struct clk_core *parent; - if (!clk) - return NULL; - - parent = clk_core_get_parent_by_index(clk->core, index); + parent = clk_core_get_parent_by_index(hw->core, index); - return !parent ? NULL : parent->hw->clk; + return !parent ? NULL : parent->hw; } -EXPORT_SYMBOL_GPL(clk_get_parent_by_index); +EXPORT_SYMBOL_GPL(clk_hw_get_parent_by_index); unsigned int __clk_get_enable_count(struct clk *clk) { @@ -387,14 +396,11 @@ out: return ret; } -unsigned long __clk_get_rate(struct clk *clk) +unsigned long clk_hw_get_rate(const struct clk_hw *hw) { - if (!clk) - return 0; - - return clk_core_get_rate_nolock(clk->core); + return clk_core_get_rate_nolock(hw->core); } -EXPORT_SYMBOL_GPL(__clk_get_rate); +EXPORT_SYMBOL_GPL(clk_hw_get_rate); static unsigned long __clk_get_accuracy(struct clk_core *core) { @@ -410,12 +416,15 @@ unsigned long __clk_get_flags(struct clk *clk) } EXPORT_SYMBOL_GPL(__clk_get_flags); -bool __clk_is_prepared(struct clk *clk) +unsigned long clk_hw_get_flags(const struct clk_hw *hw) { - if (!clk) - return false; + return hw->core->flags; +} +EXPORT_SYMBOL_GPL(clk_hw_get_flags); - return clk_core_is_prepared(clk->core); +bool clk_hw_is_prepared(const struct clk_hw *hw) +{ + return clk_core_is_prepared(hw->core); } bool __clk_is_enabled(struct clk *clk) @@ -436,28 +445,31 @@ static bool mux_is_better_rate(unsigned long rate, unsigned long now, return now <= rate && now > best; } -static long -clk_mux_determine_rate_flags(struct clk_hw *hw, unsigned long rate, - unsigned long min_rate, - unsigned long max_rate, - unsigned long *best_parent_rate, - struct clk_hw **best_parent_p, +static 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; - unsigned long parent_rate, best = 0; + 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) - best = __clk_determine_rate(parent ? parent->hw : NULL, - rate, min_rate, max_rate); - else if (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 + } else { best = clk_core_get_rate_nolock(core); + } + goto out; } @@ -467,24 +479,33 @@ clk_mux_determine_rate_flags(struct clk_hw *hw, unsigned long rate, parent = clk_core_get_parent_by_index(core, i); if (!parent) continue; - if (core->flags & CLK_SET_RATE_PARENT) - parent_rate = __clk_determine_rate(parent->hw, rate, - min_rate, - max_rate); - else - parent_rate = clk_core_get_rate_nolock(parent); - if (mux_is_better_rate(rate, parent_rate, best, flags)) { + + 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_rate; + best = parent_req.rate; } } + if (!best_parent) + return -EINVAL; + out: if (best_parent) - *best_parent_p = best_parent->hw; - *best_parent_rate = best; + req->best_parent_hw = best_parent->hw; + req->best_parent_rate = best; + req->rate = best; - return best; + return 0; } struct clk *__clk_lookup(const char *name) @@ -500,8 +521,8 @@ static void clk_core_get_boundaries(struct clk_core *core, { struct clk *clk_user; - *min_rate = 0; - *max_rate = ULONG_MAX; + *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); @@ -510,33 +531,30 @@ static void clk_core_get_boundaries(struct clk_core *core, *max_rate = min(*max_rate, clk_user->max_rate); } +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. */ -long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate, - unsigned long min_rate, - unsigned long max_rate, - unsigned long *best_parent_rate, - struct clk_hw **best_parent_p) +int __clk_mux_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) { - return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate, - best_parent_rate, - best_parent_p, 0); + return clk_mux_determine_rate_flags(hw, req, 0); } EXPORT_SYMBOL_GPL(__clk_mux_determine_rate); -long __clk_mux_determine_rate_closest(struct clk_hw *hw, unsigned long rate, - unsigned long min_rate, - unsigned long max_rate, - unsigned long *best_parent_rate, - struct clk_hw **best_parent_p) +int __clk_mux_determine_rate_closest(struct clk_hw *hw, + struct clk_rate_request *req) { - return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate, - best_parent_rate, - best_parent_p, - CLK_MUX_ROUND_CLOSEST); + return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST); } EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest); @@ -759,14 +777,11 @@ int clk_enable(struct clk *clk) } EXPORT_SYMBOL_GPL(clk_enable); -static unsigned long clk_core_round_rate_nolock(struct clk_core *core, - unsigned long rate, - unsigned long min_rate, - unsigned long max_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; - struct clk_hw *parent_hw; + long rate; lockdep_assert_held(&prepare_lock); @@ -774,21 +789,30 @@ static unsigned long clk_core_round_rate_nolock(struct clk_core *core, return 0; parent = core->parent; - if (parent) - parent_rate = parent->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; + } if (core->ops->determine_rate) { - parent_hw = parent ? parent->hw : NULL; - return core->ops->determine_rate(core->hw, rate, - min_rate, max_rate, - &parent_rate, &parent_hw); - } else if (core->ops->round_rate) - return core->ops->round_rate(core->hw, rate, &parent_rate); - else if (core->flags & CLK_SET_RATE_PARENT) - return clk_core_round_rate_nolock(core->parent, rate, min_rate, - max_rate); - else - return core->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 0; } /** @@ -800,38 +824,32 @@ static unsigned long clk_core_round_rate_nolock(struct clk_core *core, * * Useful for clk_ops such as .set_rate and .determine_rate. */ -unsigned long __clk_determine_rate(struct clk_hw *hw, - unsigned long rate, - unsigned long min_rate, - unsigned long max_rate) +int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { - if (!hw) + if (!hw) { + req->rate = 0; return 0; + } - return clk_core_round_rate_nolock(hw->core, rate, min_rate, max_rate); + return clk_core_round_rate_nolock(hw->core, req); } EXPORT_SYMBOL_GPL(__clk_determine_rate); -/** - * __clk_round_rate - round the given rate for a clk - * @clk: round the rate of this clock - * @rate: the rate which is to be rounded - * - * Useful for clk_ops such as .set_rate - */ -unsigned long __clk_round_rate(struct clk *clk, unsigned long rate) +unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate) { - unsigned long min_rate; - unsigned long max_rate; + int ret; + struct clk_rate_request req; - if (!clk) - return 0; + clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate); + req.rate = rate; - clk_core_get_boundaries(clk->core, &min_rate, &max_rate); + ret = clk_core_round_rate_nolock(hw->core, &req); + if (ret) + return 0; - return clk_core_round_rate_nolock(clk->core, rate, min_rate, max_rate); + return req.rate; } -EXPORT_SYMBOL_GPL(__clk_round_rate); +EXPORT_SYMBOL_GPL(clk_hw_round_rate); /** * clk_round_rate - round the given rate for a clk @@ -844,16 +862,24 @@ EXPORT_SYMBOL_GPL(__clk_round_rate); */ 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); @@ -1064,18 +1090,40 @@ static int clk_fetch_parent_index(struct clk_core *core, 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; @@ -1160,14 +1208,8 @@ static int __clk_set_parent(struct clk_core *core, struct clk_core *parent, flags = clk_enable_lock(); clk_reparent(core, old_parent); clk_enable_unlock(flags); + __clk_set_parent_after(core, old_parent, parent); - if (core->prepare_count) { - flags = clk_enable_lock(); - clk_core_disable(core); - clk_core_disable(parent); - clk_enable_unlock(flags); - clk_core_unprepare(parent); - } return ret; } @@ -1249,7 +1291,6 @@ static struct clk_core *clk_calc_new_rates(struct clk_core *core, { struct clk_core *top = core; struct clk_core *old_parent, *parent; - struct clk_hw *parent_hw; unsigned long best_parent_rate = 0; unsigned long new_rate; unsigned long min_rate; @@ -1270,20 +1311,29 @@ static struct clk_core *clk_calc_new_rates(struct clk_core *core, /* find the closest rate and parent clk/rate */ if (core->ops->determine_rate) { - parent_hw = parent ? parent->hw : NULL; - ret = core->ops->determine_rate(core->hw, rate, - min_rate, - max_rate, - &best_parent_rate, - &parent_hw); + 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); if (ret < 0) return NULL; - new_rate = ret; - parent = parent_hw ? parent_hw->core : 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); + &best_parent_rate); if (ret < 0) return NULL; @@ -1592,8 +1642,12 @@ struct clk *clk_get_parent(struct clk *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; @@ -2324,13 +2378,17 @@ static int __clk_init(struct device *dev, struct clk *clk_user) * clocks and re-parent any that are children of the clock currently * being clk_init'd. */ - if (core->parent) + if (core->parent) { hlist_add_head(&core->child_node, &core->parent->children); - else if (core->flags & CLK_IS_ROOT) + core->orphan = core->parent->orphan; + } else if (core->flags & CLK_IS_ROOT) { hlist_add_head(&core->child_node, &clk_root_list); - else + 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 @@ -2379,7 +2437,8 @@ static int __clk_init(struct device *dev, struct clk *clk_user) hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { if (orphan->num_parents && orphan->ops->get_parent) { i = orphan->ops->get_parent(orphan->hw); - if (!strcmp(core->name, orphan->parent_names[i])) + if (i >= 0 && i < orphan->num_parents && + !strcmp(core->name, orphan->parent_names[i])) clk_core_reparent(orphan, core); continue; } @@ -2479,6 +2538,8 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw) 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 */ @@ -3054,8 +3115,6 @@ struct clock_provider { struct list_head node; }; -static LIST_HEAD(clk_provider_list); - /* * This function looks for a parent clock. If there is one, then it * checks that the provider for this parent clock was initialized, in @@ -3106,14 +3165,24 @@ void __init of_clk_init(const struct of_device_id *matches) struct clock_provider *clk_provider, *next; bool is_init_done; bool force = false; + LIST_HEAD(clk_provider_list); if (!matches) 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 = - kzalloc(sizeof(struct clock_provider), GFP_KERNEL); + 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); + kfree(clk_provider); + } + return; + } parent->clk_init_cb = match->data; parent->np = np; |