Remove the clocksource related clock notifier which tries to update the clocksource frequency in case the timer's input frequency changes. The notifier's approach - unregistering and re-registering the clocksource with the new frequency - is destined to fail, if the TTC is the only available HR clocksource.
Signed-off-by: Soren Brinkmann <[email protected]> --- drivers/clocksource/cadence_ttc_timer.c | 44 --------------------------------- 1 file changed, 44 deletions(-) diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c index b2bb3a4b..99ec898 100644 --- a/drivers/clocksource/cadence_ttc_timer.c +++ b/drivers/clocksource/cadence_ttc_timer.c @@ -219,43 +219,6 @@ static void ttc_set_mode(enum clock_event_mode mode, } } -static int ttc_rate_change_clocksource_cb(struct notifier_block *nb, - unsigned long event, void *data) -{ - struct clk_notifier_data *ndata = data; - struct ttc_timer *ttc = to_ttc_timer(nb); - struct ttc_timer_clocksource *ttccs = container_of(ttc, - struct ttc_timer_clocksource, ttc); - - switch (event) { - case POST_RATE_CHANGE: - /* - * Do whatever is necessary to maintain a proper time base - * - * I cannot find a way to adjust the currently used clocksource - * to the new frequency. __clocksource_updatefreq_hz() sounds - * good, but does not work. Not sure what's that missing. - * - * This approach works, but triggers two clocksource switches. - * The first after unregister to clocksource jiffies. And - * another one after the register to the newly registered timer. - * - * Alternatively we could 'waste' another HW timer to ping pong - * between clock sources. That would also use one register and - * one unregister call, but only trigger one clocksource switch - * for the cost of another HW timer used by the OS. - */ - clocksource_unregister(&ttccs->cs); - clocksource_register_hz(&ttccs->cs, - ndata->new_rate / PRESCALE); - /* fall through */ - case PRE_RATE_CHANGE: - case ABORT_RATE_CHANGE: - default: - return NOTIFY_DONE; - } -} - static void __init ttc_setup_clocksource(struct clk *clk, void __iomem *base) { struct ttc_timer_clocksource *ttccs; @@ -273,13 +236,6 @@ static void __init ttc_setup_clocksource(struct clk *clk, void __iomem *base) return; } - ttccs->ttc.clk_rate_change_nb.notifier_call = - ttc_rate_change_clocksource_cb; - ttccs->ttc.clk_rate_change_nb.next = NULL; - if (clk_notifier_register(ttccs->ttc.clk, - &ttccs->ttc.clk_rate_change_nb)) - pr_warn("Unable to register clock notifier.\n"); - ttccs->ttc.base_addr = base; ttccs->cs.name = "ttc_clocksource"; ttccs->cs.rating = 200; -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
