booke_ppc: limit booke timer to max when timeout overflow

Limit watchdog and fit timer to maximum timeout value which
qemu timer can support (INT64_MAX). This maximum timeout will be
hundreds of years, so limiting to max timeout is pretty safe.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Bharat Bhushan 2013-06-12 18:00:50 +05:30 committed by Alexander Graf
parent f1ff0e89c8
commit ab8131afee
1 changed files with 20 additions and 4 deletions

View File

@ -131,17 +131,33 @@ static void booke_update_fixed_timer(CPUPPCState *env,
struct QEMUTimer *timer)
{
ppc_tb_t *tb_env = env->tb_env;
uint64_t lapse;
uint64_t delta_tick, ticks = 0;
uint64_t tb;
uint64_t period = 1 << (target_bit + 1);
uint64_t period;
uint64_t now;
now = qemu_get_clock_ns(vm_clock);
tb = cpu_ppc_get_tb(tb_env, now, tb_env->tb_offset);
period = 1ULL << target_bit;
delta_tick = period - (tb & (period - 1));
lapse = period - ((tb - (1 << target_bit)) & (period - 1));
/* the timer triggers only when the selected bit toggles from 0 to 1 */
if (tb & period) {
ticks = period;
}
*next = now + muldiv64(lapse, get_ticks_per_sec(), tb_env->tb_freq);
if (ticks + delta_tick < ticks) {
/* Overflow, so assume the biggest number we can express. */
ticks = UINT64_MAX;
} else {
ticks += delta_tick;
}
*next = now + muldiv64(ticks, get_ticks_per_sec(), tb_env->tb_freq);
if ((*next < now) || (*next > INT64_MAX)) {
/* Overflow, so assume the biggest number the qemu timer supports. */
*next = INT64_MAX;
}
/* XXX: If expire time is now. We can't run the callback because we don't
* have access to it. So we just set the timer one nanosecond later.