diff options
author | Patrick Wildt <patrick@cvs.openbsd.org> | 2017-02-07 21:51:04 +0000 |
---|---|---|
committer | Patrick Wildt <patrick@cvs.openbsd.org> | 2017-02-07 21:51:04 +0000 |
commit | 32186ec30002874db64d52ca745048834a153ae7 (patch) | |
tree | 37365505d0717e259aba9d6f0dd8bd53d2803173 /sys/arch/arm64/dev | |
parent | 5bd2506a1256271eefbc5a5fb94919ea766092cb (diff) |
The default frequency we chose for the generic timer does not always ring
true. Instead, unless overwritten by the device tree, we should ask the
generic timer for its frequency. This fixes time on my AMD Seattle and
should improve time management on QEMU as well.
Diffstat (limited to 'sys/arch/arm64/dev')
-rw-r--r-- | sys/arch/arm64/dev/agtimer.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/sys/arch/arm64/dev/agtimer.c b/sys/arch/arm64/dev/agtimer.c index 451f439715f..bbcb37ee038 100644 --- a/sys/arch/arm64/dev/agtimer.c +++ b/sys/arch/arm64/dev/agtimer.c @@ -1,4 +1,4 @@ -/* $OpenBSD: agtimer.c,v 1.3 2017/01/23 10:15:53 kettenis Exp $ */ +/* $OpenBSD: agtimer.c,v 1.4 2017/02/07 21:51:03 patrick Exp $ */ /* * Copyright (c) 2011 Dale Rahn <drahn@openbsd.org> * Copyright (c) 2013 Patrick Wildt <patrick@blueri.se> @@ -100,6 +100,16 @@ agtimer_readcnt64(void) return (val); } +static inline uint64_t +agtimer_get_freq(void) +{ + uint64_t val; + + __asm volatile("MRS %x0, CNTFRQ_EL0" : "=r" (val)); + + return (val); +} + static inline int agtimer_get_ctrl(void) { @@ -149,6 +159,8 @@ agtimer_attach(struct device *parent, struct device *self, void *aux) sc->sc_node = faa->fa_node; + if (agtimer_get_freq() != 0) + agtimer_frequency = agtimer_get_freq(); agtimer_frequency = OF_getpropint(sc->sc_node, "clock-frequency", agtimer_frequency); sc->sc_ticks_per_second = agtimer_frequency; |