Commit 1403f364 authored by Cédric Le Goater's avatar Cédric Le Goater Committed by Peter Maydell
Browse files

timer/aspeed: fix timer enablement when a reload is not set 



When a timer is enabled before a reload value is set, the controller
waits for a reload value to be set before starting decrementing. This
fix tries to cover that case by changing the timer expiry only when
a reload value is valid.

Signed-off-by: default avatarCédric Le Goater <clg@kaod.org>
Reviewed-by: default avatarAndrew Jeffery <andrew@aj.id.au>
Message-id: 1496739312-32304-1-git-send-email-clg@kaod.org
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parent a87e81b9

hw/timer/aspeed_timer.c

+29 −8
Original line number Diff line number Diff line
@@ -130,15 +130,26 @@ static uint64_t calculate_next(struct AspeedTimer *t) 
            next = seq[1];

        } else if (now < seq[2]) {

            next = seq[2];

        } else {

        } else if (t->reload) {

            reload_ns = muldiv64(t->reload, NANOSECONDS_PER_SECOND, rate);

            t->start = now - ((now - t->start) % reload_ns);

        } else {

            /* no reload value, return 0 */

            break;

        }

    }



    return next;

}



static void aspeed_timer_mod(AspeedTimer *t)

{

    uint64_t next = calculate_next(t);

    if (next) {

        timer_mod(&t->timer, next);

    }

}



static void aspeed_timer_expire(void *opaque)

{

    AspeedTimer *t = opaque;
@@ -164,7 +175,7 @@ static void aspeed_timer_expire(void *opaque) 
        qemu_set_irq(t->irq, t->level);

    }



    timer_mod(&t->timer, calculate_next(t));

    aspeed_timer_mod(t);

}



static uint64_t aspeed_timer_get_value(AspeedTimer *t, int reg)
@@ -227,10 +238,23 @@ static void aspeed_timer_set_value(AspeedTimerCtrlState *s, int timer, int reg, 
                                   uint32_t value)

{

    AspeedTimer *t;

    uint32_t old_reload;



    trace_aspeed_timer_set_value(timer, reg, value);

    t = &s->timers[timer];

    switch (reg) {

    case TIMER_REG_RELOAD:

        old_reload = t->reload;

        t->reload = value;



        /* If the reload value was not previously set, or zero, and

         * the current value is valid, try to start the timer if it is

         * enabled.

         */

        if (old_reload || !t->reload) {

            break;

        }



    case TIMER_REG_STATUS:

        if (timer_enabled(t)) {

            uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
@@ -238,17 +262,14 @@ static void aspeed_timer_set_value(AspeedTimerCtrlState *s, int timer, int reg, 
            uint32_t rate = calculate_rate(t);



            t->start += muldiv64(delta, NANOSECONDS_PER_SECOND, rate);

            timer_mod(&t->timer, calculate_next(t));

            aspeed_timer_mod(t);

        }

        break;

    case TIMER_REG_RELOAD:

        t->reload = value;

        break;

    case TIMER_REG_MATCH_FIRST:

    case TIMER_REG_MATCH_SECOND:

        t->match[reg - 2] = value;

        if (timer_enabled(t)) {

            timer_mod(&t->timer, calculate_next(t));

            aspeed_timer_mod(t);

        }

        break;

    default:
@@ -268,7 +289,7 @@ static void aspeed_timer_ctrl_enable(AspeedTimer *t, bool enable) 
    trace_aspeed_timer_ctrl_enable(t->id, enable);

    if (enable) {

        t->start = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);

        timer_mod(&t->timer, calculate_next(t));

        aspeed_timer_mod(t);

    } else {

        timer_del(&t->timer);

    }