The Sun4m architecture has one 'system' timer and one timer per CPU.
The CPU timers can be configured in two modes :
* 22bits Counter/Timer. Periodic interrupts.
* 54bits User timer. For profiling. In this mode, the Run/Stop bit
controls the timer.
The run/stop bit controls the timer only when it is in "User" mode, but
its state shall be persistent.
Signed-off-by: Olivier Danet <address@hidden>
---
hw/timer/slavio_timer.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
diff --git a/hw/timer/slavio_timer.c b/hw/timer/slavio_timer.c
index f75b914..e4dccea 100644
--- a/hw/timer/slavio_timer.c
+++ b/hw/timer/slavio_timer.c
@@ -51,7 +51,7 @@ typedef struct CPUTimerState {
ptimer_state *timer;
uint32_t count, counthigh, reached;
/* processor only */
- uint32_t running;
+ uint32_t run;
uint64_t limit;
} CPUTimerState;
@@ -177,7 +177,7 @@ static uint64_t slavio_timer_mem_readl(void *opaque,
hwaddr addr,
// only available in processor counter/timer
// read start/stop status
if (timer_index > 0) {
- ret = t->running;
+ ret = t->run;
} else {
ret = 0;
}
@@ -260,16 +260,15 @@ static void slavio_timer_mem_writel(void *opaque,
hwaddr addr,
case TIMER_STATUS:
if (slavio_timer_is_user(tc)) {
// start/stop user counter
- if ((val & 1) && !t->running) {
+ if (val & 1) {
trace_slavio_timer_mem_writel_status_start(timer_index);
ptimer_run(t->timer, 0);
- t->running = 1;
- } else if (!(val & 1) && t->running) {
+ } else {
trace_slavio_timer_mem_writel_status_stop(timer_index);
ptimer_stop(t->timer);
- t->running = 0;
}
}
+ t->run = val & 1;
break;
case TIMER_MODE:
if (timer_index == 0) {
@@ -284,8 +283,9 @@ static void slavio_timer_mem_writel(void *opaque,
hwaddr addr,
if (val & processor) { // counter -> user timer
qemu_irq_lower(curr_timer->irq);
// counters are always running
- ptimer_stop(curr_timer->timer);
- curr_timer->running = 0;
+ if (!curr_timer->run) {
+ ptimer_stop(curr_timer->timer);
+ }
// user timer limit is always the same
curr_timer->limit = TIMER_MAX_COUNT64;
ptimer_set_limit(curr_timer->timer,
@@ -296,13 +296,8 @@ static void slavio_timer_mem_writel(void *opaque,
hwaddr addr,
s->cputimer_mode |= processor;
trace_slavio_timer_mem_writel_mode_user(timer_index);
} else { // user timer -> counter
- // stop the user timer if it is running
- if (curr_timer->running) {
- ptimer_stop(curr_timer->timer);
- }
// start the counter
ptimer_run(curr_timer->timer, 0);
- curr_timer->running = 1;
// clear this processors user timer bit in config
// register
s->cputimer_mode &= ~processor;
@@ -340,7 +335,7 @@ static const VMStateDescription vmstate_timer = {
VMSTATE_UINT32(count, CPUTimerState),
VMSTATE_UINT32(counthigh, CPUTimerState),
VMSTATE_UINT32(reached, CPUTimerState),
- VMSTATE_UINT32(running, CPUTimerState),
+ VMSTATE_UINT32(run , CPUTimerState),
VMSTATE_PTIMER(timer, CPUTimerState),
VMSTATE_END_OF_LIST()
}
@@ -373,7 +368,7 @@ static void slavio_timer_reset(DeviceState *d)
ptimer_set_limit(curr_timer->timer,
LIMIT_TO_PERIODS(TIMER_MAX_COUNT32), 1);
ptimer_run(curr_timer->timer, 0);
- curr_timer->running = 1;
+ curr_timer->run = 1;
}
}
s->cputimer_mode = 0;