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authorThomas Gleixner <tglx@linutronix.de>2020-12-12 15:53:15 +0300
committerThomas Gleixner <tglx@linutronix.de>2020-12-12 15:53:15 +0300
commit464d2ff716c37d83e8bb0c4f1c1acfc02dbc9984 (patch)
tree71dbe534d76f3954e9e7ff2eab618ded7d2850c2 /drivers/clocksource/arm_arch_timer.c
parentaa3b66f401b372598b29421bab4d17b631b92407 (diff)
parent8ae954caf49ac403c177d117fb8e05cbc866aa3c (diff)
downloadlinux-464d2ff716c37d83e8bb0c4f1c1acfc02dbc9984.tar.xz
Merge tag 'timers-v5.11-2' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core
Pull clocksource/events updates from Daniel Lezcano: - Fix error handling if no clock is available on dw_apb_timer_of (Dinh Nguyen) - Fix overhead for erratum handling when the timer has no erratum and fix fault programing for the event stream on the arm arch timer (Keqian Zhu) - Fix potential deadlock when calling runtime PM on sh_cmt (Niklas Söderlund)
Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
-rw-r--r--drivers/clocksource/arm_arch_timer.c27
1 files changed, 18 insertions, 9 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 6c3e84180146..d0177824c518 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -396,10 +396,10 @@ static void erratum_set_next_event_tval_generic(const int access, unsigned long
ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
if (access == ARCH_TIMER_PHYS_ACCESS) {
- cval = evt + arch_counter_get_cntpct();
+ cval = evt + arch_counter_get_cntpct_stable();
write_sysreg(cval, cntp_cval_el0);
} else {
- cval = evt + arch_counter_get_cntvct();
+ cval = evt + arch_counter_get_cntvct_stable();
write_sysreg(cval, cntv_cval_el0);
}
@@ -822,15 +822,24 @@ static void arch_timer_evtstrm_enable(int divider)
static void arch_timer_configure_evtstream(void)
{
- int evt_stream_div, pos;
+ int evt_stream_div, lsb;
+
+ /*
+ * As the event stream can at most be generated at half the frequency
+ * of the counter, use half the frequency when computing the divider.
+ */
+ evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2;
+
+ /*
+ * Find the closest power of two to the divisor. If the adjacent bit
+ * of lsb (last set bit, starts from 0) is set, then we use (lsb + 1).
+ */
+ lsb = fls(evt_stream_div) - 1;
+ if (lsb > 0 && (evt_stream_div & BIT(lsb - 1)))
+ lsb++;
- /* Find the closest power of two to the divisor */
- evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ;
- pos = fls(evt_stream_div);
- if (pos > 1 && !(evt_stream_div & (1 << (pos - 2))))
- pos--;
/* enable event stream */
- arch_timer_evtstrm_enable(min(pos, 15));
+ arch_timer_evtstrm_enable(max(0, min(lsb, 15)));
}
static void arch_counter_set_user_access(void)