diff options
author | Saravana Kannan <saravanak@google.com> | 2019-11-06 12:21:35 -0800 |
---|---|---|
committer | Sumit Semwal <sumit.semwal@linaro.org> | 2021-01-27 23:55:01 +0530 |
commit | 0689cf44ba33258658f19613e5a394a0d19dabbc (patch) | |
tree | 84fb12a85163063a0683e039da3be52ed5e50b8b | |
parent | 92e7e7bdaa21982b273f64cc199f115c65bd4c3b (diff) |
ANDROID: GKI: clk: Add support for clock providers with sync state
Clock providers whose drivers have sync_state() implemented will disable
their clocks once all their consumers have probed. So during
late_initcall_sync(), don't disable unused clocks of these clock
providers.
Also, provide a clk_sync_state() API that clock providers can use to
disable all their unused clocks once they get their sync_state()
callback.
Bug: 144066914
Signed-off-by: Saravana Kannan <saravanak@google.com>
Change-Id: Id01bfc15347812faa19802463c088db162c7d117
-rw-r--r-- | drivers/clk/clk.c | 65 | ||||
-rw-r--r-- | include/linux/clk-provider.h | 2 |
2 files changed, 67 insertions, 0 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 8c1d04db990d..29b2831b9cd0 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -72,6 +72,8 @@ struct clk_core { unsigned long flags; bool orphan; bool rpm_enabled; + bool need_sync; + bool boot_enabled; unsigned int enable_count; unsigned int prepare_count; unsigned int protect_count; @@ -1298,6 +1300,38 @@ static int __init clk_disable_unused(void) } late_initcall_sync(clk_disable_unused); +static void clk_unprepare_disable_dev_subtree(struct clk_core *core, + struct device *dev) +{ + struct clk_core *child; + + lockdep_assert_held(&prepare_lock); + + hlist_for_each_entry(child, &core->children, child_node) + clk_unprepare_disable_dev_subtree(child, dev); + + if (core->dev != dev || !core->need_sync) + return; + + clk_core_disable_unprepare(core); +} + +void clk_sync_state(struct device *dev) +{ + struct clk_core *core; + + clk_prepare_lock(); + + hlist_for_each_entry(core, &clk_root_list, child_node) + clk_unprepare_disable_dev_subtree(core, dev); + + hlist_for_each_entry(core, &clk_orphan_list, child_node) + clk_unprepare_disable_dev_subtree(core, dev); + + clk_prepare_unlock(); +} +EXPORT_SYMBOL_GPL(clk_sync_state); + static int clk_core_determine_round_nolock(struct clk_core *core, struct clk_rate_request *req) { @@ -1704,6 +1738,33 @@ int clk_hw_get_parent_index(struct clk_hw *hw) } EXPORT_SYMBOL_GPL(clk_hw_get_parent_index); +static void clk_core_hold_state(struct clk_core *core) +{ + if (core->need_sync || !core->boot_enabled) + return; + + if (core->orphan || !dev_has_sync_state(core->dev)) + return; + + if (core->flags & CLK_DONT_HOLD_STATE) + return; + + core->need_sync = !clk_core_prepare_enable(core); +} + +static void __clk_core_update_orphan_hold_state(struct clk_core *core) +{ + struct clk_core *child; + + if (core->orphan) + return; + + clk_core_hold_state(core); + + hlist_for_each_entry(child, &core->children, child_node) + __clk_core_update_orphan_hold_state(child); +} + /* * Update the orphan status of @core and all its children. */ @@ -3379,6 +3440,7 @@ static void clk_core_reparent_orphans_nolock(void) __clk_set_parent_after(orphan, parent, NULL); __clk_recalc_accuracies(orphan); __clk_recalc_rates(orphan, 0); + __clk_core_update_orphan_hold_state(orphan); } } } @@ -3537,6 +3599,8 @@ static int __clk_core_init(struct clk_core *core) rate = 0; core->rate = core->req_rate = rate; + core->boot_enabled = clk_core_is_enabled(core); + /* * Enable CLK_IS_CRITICAL clocks so newly added critical clocks * don't get accidentally disabled when walking the orphan tree and @@ -3563,6 +3627,7 @@ static int __clk_core_init(struct clk_core *core) } } + clk_core_hold_state(core); clk_core_reparent_orphans_nolock(); diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index e4316890661a..b6c2ff3d74e6 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -32,6 +32,7 @@ #define CLK_OPS_PARENT_ENABLE BIT(12) /* duty cycle call may be forwarded to the parent clock */ #define CLK_DUTY_CYCLE_PARENT BIT(13) +#define CLK_DONT_HOLD_STATE BIT(14) /* Don't hold state */ struct clk; struct clk_hw; @@ -1110,6 +1111,7 @@ void devm_clk_unregister(struct device *dev, struct clk *clk); void clk_hw_unregister(struct clk_hw *hw); void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw); +void clk_sync_state(struct device *dev); /* helper functions */ const char *__clk_get_name(const struct clk *clk); |