diff options
| -rw-r--r-- | hw/watchdog/wdt_i6300esb.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/hw/watchdog/wdt_i6300esb.c b/hw/watchdog/wdt_i6300esb.c index e694fa9969..4ebdbb8586 100644 --- a/hw/watchdog/wdt_i6300esb.c +++ b/hw/watchdog/wdt_i6300esb.c @@ -125,8 +125,14 @@ static void i6300esb_restart_timer(I6300State *d, int stage) else timeout <<= 5; - /* Get the timeout in units of ticks_per_sec. */ - timeout = get_ticks_per_sec() * timeout / 33000000; + /* Get the timeout in units of ticks_per_sec. + * + * ticks_per_sec is typically 10^9 == 0x3B9ACA00 (30 bits), with + * 20 bits of user supplied preload, and 15 bits of scale, the + * multiply here can exceed 64-bits, before we divide by 33MHz, so + * we use a higher-precision intermediate result. + */ + timeout = muldiv64(get_ticks_per_sec(), timeout, 33000000); i6300esb_debug("stage %d, timeout %" PRIi64 "\n", d->stage, timeout); |