diff options
| author | Linus Walleij <linus.walleij@linaro.org> | 2018-11-15 16:32:03 +0300 |
|---|---|---|
| committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2018-12-19 00:22:23 +0300 |
| commit | 85b6fcadcf6626ad520376eacfb2b77090e782ab (patch) | |
| tree | 5b0ef9aa8494e566f112d0201d546ac6325f7d22 /drivers/clocksource/nomadik-mtu.c | |
| parent | bc0750e464d41e1234f56471b8f626b8d945b1a8 (diff) | |
| download | linux-85b6fcadcf6626ad520376eacfb2b77090e782ab.tar.xz | |
clocksource/drivers/ux500: Drop Ux500 custom SCHED_CLOCK
The two drivers used for Ux500 sched_clock use two Kconfig
symbols to select which of the two gets used as sched_clock.
This isn't right: the workaround is trying to make sure that
the NONSTOP timer is used for sched_clock in order to keep
that clock ticking consistently over a suspend/resume
cycle. (Otherwise sched_clock simply stops during suspend
and continues after resume).
This will notably affect any timetstamped debug prints,
so that they show the absolute number of seconds since the
system was booted and does not loose wall-clock time during
suspend and resume as if time stood still.
The real way to fix this problem is to make sched_clock
take advantage of any NONSTOP clock source on the system
and adjust accordingly, not to try to work around this by
using a different sched_clock depending on what system
we are compiling for. This can solve the problem for
everyone instead of providing a local solution.
Cc: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Diffstat (limited to 'drivers/clocksource/nomadik-mtu.c')
| -rw-r--r-- | drivers/clocksource/nomadik-mtu.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/drivers/clocksource/nomadik-mtu.c b/drivers/clocksource/nomadik-mtu.c index 8e4ddb9420c6..19b336c9b417 100644 --- a/drivers/clocksource/nomadik-mtu.c +++ b/drivers/clocksource/nomadik-mtu.c @@ -69,7 +69,6 @@ static u32 clk_prescale; static u32 nmdk_cycle; /* write-once */ static struct delay_timer mtu_delay_timer; -#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK /* * Override the global weak sched_clock symbol with this * local implementation which uses the clocksource to get some @@ -82,7 +81,6 @@ static u64 notrace nomadik_read_sched_clock(void) return -readl(mtu_base + MTU_VAL(0)); } -#endif static unsigned long nmdk_timer_read_current_timer(void) { @@ -234,9 +232,7 @@ static int __init nmdk_timer_init(void __iomem *base, int irq, return ret; } -#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK sched_clock_register(nomadik_read_sched_clock, 32, rate); -#endif /* Timer 1 is used for events, register irq and clockevents */ setup_irq(irq, &nmdk_timer_irq); |