diff options
| -rw-r--r-- | hw/timer/imx_epit.c | 73 | ||||
| -rw-r--r-- | include/hw/timer/imx_epit.h | 2 |
2 files changed, 28 insertions, 47 deletions
diff --git a/hw/timer/imx_epit.c b/hw/timer/imx_epit.c index e04427542f..cf13496165 100644 --- a/hw/timer/imx_epit.c +++ b/hw/timer/imx_epit.c @@ -73,27 +73,14 @@ static void imx_epit_update_int(IMXEPITState *s) } } -/* - * Must be called from within a ptimer_transaction_begin/commit block - * for both s->timer_cmp and s->timer_reload. - */ -static void imx_epit_set_freq(IMXEPITState *s) +static uint32_t imx_epit_get_freq(IMXEPITState *s) { - uint32_t clksrc; - uint32_t prescaler; - - clksrc = extract32(s->cr, CR_CLKSRC_SHIFT, CR_CLKSRC_BITS); - prescaler = 1 + extract32(s->cr, CR_PRESCALE_SHIFT, CR_PRESCALE_BITS); - - s->freq = imx_ccm_get_clock_frequency(s->ccm, - imx_epit_clocks[clksrc]) / prescaler; - - DPRINTF("Setting ptimer frequency to %u\n", s->freq); - - if (s->freq) { - ptimer_set_freq(s->timer_reload, s->freq); - ptimer_set_freq(s->timer_cmp, s->freq); - } + uint32_t clksrc = extract32(s->cr, CR_CLKSRC_SHIFT, CR_CLKSRC_BITS); + uint32_t prescaler = 1 + extract32(s->cr, CR_PRESCALE_SHIFT, CR_PRESCALE_BITS); + uint32_t f_in = imx_ccm_get_clock_frequency(s->ccm, imx_epit_clocks[clksrc]); + uint32_t freq = f_in / prescaler; + DPRINTF("ptimer frequency is %u\n", freq); + return freq; } /* @@ -110,32 +97,23 @@ static void imx_epit_reset(IMXEPITState *s, bool is_hard_reset) s->sr = 0; s->lr = EPIT_TIMER_MAX; s->cmp = 0; - s->cnt = 0; ptimer_transaction_begin(s->timer_cmp); ptimer_transaction_begin(s->timer_reload); - /* stop both timers */ + + /* + * The reset switches off the input clock, so even if the CR.EN is still + * set, the timers are no longer running. + */ + assert(imx_epit_get_freq(s) == 0); ptimer_stop(s->timer_cmp); ptimer_stop(s->timer_reload); - /* compute new frequency */ - imx_epit_set_freq(s); /* init both timers to EPIT_TIMER_MAX */ ptimer_set_limit(s->timer_cmp, EPIT_TIMER_MAX, 1); ptimer_set_limit(s->timer_reload, EPIT_TIMER_MAX, 1); - if (s->freq && (s->cr & CR_EN)) { - /* if the timer is still enabled, restart it */ - ptimer_run(s->timer_reload, 0); - } ptimer_transaction_commit(s->timer_cmp); ptimer_transaction_commit(s->timer_reload); } -static uint32_t imx_epit_update_count(IMXEPITState *s) -{ - s->cnt = ptimer_get_count(s->timer_reload); - - return s->cnt; -} - static uint64_t imx_epit_read(void *opaque, hwaddr offset, unsigned size) { IMXEPITState *s = IMX_EPIT(opaque); @@ -159,8 +137,7 @@ static uint64_t imx_epit_read(void *opaque, hwaddr offset, unsigned size) break; case 4: /* CNT */ - imx_epit_update_count(s); - reg_value = s->cnt; + reg_value = ptimer_get_count(s->timer_reload); break; default: @@ -179,7 +156,7 @@ static void imx_epit_reload_compare_timer(IMXEPITState *s) { if ((s->cr & (CR_EN | CR_OCIEN)) == (CR_EN | CR_OCIEN)) { /* if the compare feature is on and timers are running */ - uint32_t tmp = imx_epit_update_count(s); + uint32_t tmp = ptimer_get_count(s->timer_reload); uint64_t next; if (tmp > s->cmp) { /* It'll fire in this round of the timer */ @@ -193,6 +170,7 @@ static void imx_epit_reload_compare_timer(IMXEPITState *s) static void imx_epit_write_cr(IMXEPITState *s, uint32_t value) { + uint32_t freq = 0; uint32_t oldcr = s->cr; s->cr = value & 0x03ffffff; @@ -217,12 +195,19 @@ static void imx_epit_write_cr(IMXEPITState *s, uint32_t value) ptimer_transaction_begin(s->timer_cmp); ptimer_transaction_begin(s->timer_reload); - /* Update the frequency. Has been done already in case of a reset. */ + /* + * Update the frequency. In case of a reset the input clock was + * switched off, so this can be skipped. + */ if (!(s->cr & CR_SWR)) { - imx_epit_set_freq(s); + freq = imx_epit_get_freq(s); + if (freq) { + ptimer_set_freq(s->timer_reload, freq); + ptimer_set_freq(s->timer_cmp, freq); + } } - if (s->freq && (s->cr & CR_EN) && !(oldcr & CR_EN)) { + if (freq && (s->cr & CR_EN) && !(oldcr & CR_EN)) { if (s->cr & CR_ENMOD) { if (s->cr & CR_RLD) { ptimer_set_limit(s->timer_reload, s->lr, 1); @@ -356,15 +341,13 @@ static const MemoryRegionOps imx_epit_ops = { static const VMStateDescription vmstate_imx_timer_epit = { .name = TYPE_IMX_EPIT, - .version_id = 2, - .minimum_version_id = 2, + .version_id = 3, + .minimum_version_id = 3, .fields = (VMStateField[]) { VMSTATE_UINT32(cr, IMXEPITState), VMSTATE_UINT32(sr, IMXEPITState), VMSTATE_UINT32(lr, IMXEPITState), VMSTATE_UINT32(cmp, IMXEPITState), - VMSTATE_UINT32(cnt, IMXEPITState), - VMSTATE_UINT32(freq, IMXEPITState), VMSTATE_PTIMER(timer_reload, IMXEPITState), VMSTATE_PTIMER(timer_cmp, IMXEPITState), VMSTATE_END_OF_LIST() diff --git a/include/hw/timer/imx_epit.h b/include/hw/timer/imx_epit.h index 783eaf0c3a..79aff0cec2 100644 --- a/include/hw/timer/imx_epit.h +++ b/include/hw/timer/imx_epit.h @@ -74,9 +74,7 @@ struct IMXEPITState { uint32_t sr; uint32_t lr; uint32_t cmp; - uint32_t cnt; - uint32_t freq; qemu_irq irq; }; |