From 096f2a0c6469c8a8e70cfbb83345b7ada2929f13 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Mon, 10 Oct 2022 16:47:38 +0200 Subject: clk: Update req_rate on __clk_recalc_rates() Commit cb1b1dd96241 ("clk: Set req_rate on reparenting") introduced a new function, clk_core_update_orphan_child_rates(), that updates the req_rate field on reparenting. It turns out that that function will interfere with the clock notifying done by __clk_recalc_rates(). This ends up reporting the new rate in both the old_rate and new_rate fields of struct clk_notifier_data. Since clk_core_update_orphan_child_rates() is basically __clk_recalc_rates() without the notifiers, and with the req_rate field update, we can drop clk_core_update_orphan_child_rates() entirely, and make __clk_recalc_rates() update req_rate. However, __clk_recalc_rates() is being called in several code paths: when retrieving a rate (most likely through clk_get_rate()), when changing parents (through clk_set_rate() or clk_hw_reparent()), or when updating the orphan status (through clk_core_reparent_orphans_nolock(), called at registration). Updating req_rate on reparenting or initialisation makes sense, but we shouldn't do it on clk_get_rate(). Thus an extra flag has been added to update or not req_rate depending on the context. Fixes: cb1b1dd96241 ("clk: Set req_rate on reparenting") Link: https://lore.kernel.org/linux-clk/0acc7217-762c-7c0d-45a0-55c384824ce4@samsung.com/ Link: https://lore.kernel.org/linux-clk/Y0QNSx+ZgqKSvPOC@sirena.org.uk/ Reported-by: Marek Szyprowski Reported-by: Mark Brown Suggested-by: Stephen Boyd Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20221010-rpi-clk-fixes-again-v1-1-d87ba82ac404@cerno.tech Tested-by: Marek Szyprowski Signed-off-by: Stephen Boyd --- drivers/clk/clk.c | 39 +++++++++++---------------------------- 1 file changed, 11 insertions(+), 28 deletions(-) (limited to 'drivers/clk/clk.c') diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index ec518dc5d462..47b33c5b28e1 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1760,6 +1760,7 @@ static unsigned long clk_recalc(struct clk_core *core, /** * __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 @@ -1769,7 +1770,8 @@ static unsigned long clk_recalc(struct clk_core *core, * 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; @@ -1783,6 +1785,8 @@ static void __clk_recalc_rates(struct clk_core *core, unsigned long msg) 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 @@ -1792,13 +1796,13 @@ static void __clk_recalc_rates(struct clk_core *core, unsigned long msg) __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); } @@ -1901,23 +1905,6 @@ static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan) clk_core_update_orphan_status(child, is_orphan); } -/* - * Update the orphan rate and req_rate of @core and all its children. - */ -static void clk_core_update_orphan_child_rates(struct clk_core *core) -{ - struct clk_core *child; - unsigned long parent_rate = 0; - - if (core->parent) - parent_rate = core->parent->rate; - - core->rate = core->req_rate = clk_recalc(core, parent_rate); - - hlist_for_each_entry(child, &core->children, child_node) - clk_core_update_orphan_child_rates(child); -} - static void clk_reparent(struct clk_core *core, struct clk_core *new_parent) { bool was_orphan = core->orphan; @@ -1987,8 +1974,6 @@ static struct clk_core *__clk_set_parent_before(struct clk_core *core, clk_reparent(core, parent); clk_enable_unlock(flags); - clk_core_update_orphan_child_rates(core); - return old_parent; } @@ -2034,7 +2019,6 @@ static int __clk_set_parent(struct clk_core *core, struct clk_core *parent, clk_reparent(core, old_parent); clk_enable_unlock(flags); - clk_core_update_orphan_child_rates(core); __clk_set_parent_after(core, old_parent, parent); return ret; @@ -2658,9 +2642,8 @@ static void clk_core_reparent(struct clk_core *core, struct clk_core *new_parent) { clk_reparent(core, new_parent); - clk_core_update_orphan_child_rates(core); __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) @@ -2744,9 +2727,9 @@ static int clk_core_set_parent_nolock(struct clk_core *core, /* 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); } @@ -3643,7 +3626,7 @@ static void clk_core_reparent_orphans_nolock(void) __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 -- cgit