zephyr/drivers/timer/ite_it8xxx2_timer.c

336 lines
9.1 KiB
C

/*
* Copyright (c) 2020 ITE Corporation. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT ite_it8xxx2_timer
#include <drivers/timer/system_timer.h>
#include <dt-bindings/interrupt-controller/ite-intc.h>
#include <soc.h>
#include <spinlock.h>
#include <sys_clock.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(timer, LOG_LEVEL_ERR);
/* Event timer configurations */
#define EVENT_TIMER EXT_TIMER_3
#define EVENT_TIMER_IRQ DT_INST_IRQ_BY_IDX(0, 0, irq)
#define EVENT_TIMER_FLAG DT_INST_IRQ_BY_IDX(0, 0, flags)
/* Event timer max count is 512 sec (base on clock source 32768Hz) */
#define EVENT_TIMER_MAX_CNT 0x00FFFFFFUL
#ifdef CONFIG_SOC_IT8XXX2_PLL_FLASH_48M
/*
* One shot timer configurations
*
* NOTE: Timer1/2 register address isn't regular like timer3/4/5/6/7/8, and
* timer1 is used for printing watchdog warning message. So now we use
* timer2 only one shot to wake up chip and change pll.
*/
#define WDT_BASE DT_REG_ADDR(DT_NODELABEL(twd0))
#define WDT_REG (struct wdt_it8xxx2_regs *)(WDT_BASE)
#define ONE_SHOT_TIMER_IRQ DT_IRQ_BY_IDX(DT_NODELABEL(twd0), 1, irq)
#define ONE_SHOT_TIMER_FLAG DT_IRQ_BY_IDX(DT_NODELABEL(twd0), 1, flags)
#endif
#define MS_TO_COUNT(hz, ms) ((hz) * (ms) / 1000)
/*
* One system (kernel) tick is as how much HW timer counts
*
* NOTE: Event and free run timer individually select the same clock source
* frequency, so they can use the same HW_CNT_PER_SYS_TICK to tranform
* unit between HW count and system tick. If clock source frequency is
* different, then we should define another to tranform.
*/
#define HW_CNT_PER_SYS_TICK (CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC \
/ CONFIG_SYS_CLOCK_TICKS_PER_SEC)
/* Event timer max count is as how much system (kernal) tick */
#define EVEN_TIMER_MAX_CNT_SYS_TICK (EVENT_TIMER_MAX_CNT \
/ HW_CNT_PER_SYS_TICK)
static struct k_spinlock lock;
/* Last HW count that we called sys_clock_announce() */
static volatile uint32_t last_announced_hw_cnt;
#ifdef CONFIG_SOC_IT8XXX2_PLL_FLASH_48M
static void timer_5ms_one_shot_isr(const void *unused)
{
ARG_UNUSED(unused);
/*
* We are here because we have completed changing PLL sequence,
* so disabled one shot timer interrupt.
*/
irq_disable(ONE_SHOT_TIMER_IRQ);
}
/*
* This timer is used to wake up chip from sleep mode to complete
* changing PLL sequence.
*/
void timer_5ms_one_shot(void)
{
struct wdt_it8xxx2_regs *const timer2_reg = WDT_REG;
uint32_t hw_cnt;
/* Initialize interrupt handler of one shot timer */
IRQ_CONNECT(ONE_SHOT_TIMER_IRQ, 0, timer_5ms_one_shot_isr, NULL,
ONE_SHOT_TIMER_FLAG);
/* Set rising edge triggered of one shot timer */
ite_intc_irq_priority_set(ONE_SHOT_TIMER_IRQ, 0, ONE_SHOT_TIMER_FLAG);
/* Clear interrupt status of one shot timer */
ite_intc_isr_clear(ONE_SHOT_TIMER_IRQ);
/* Set clock source of one shot timer */
timer2_reg->ET2PSR = EXT_PSR_32P768K;
/*
* Set count of one shot timer,
* and after write ET2CNTLLR timer will start
*/
hw_cnt = MS_TO_COUNT(32768, 5/*ms*/);
timer2_reg->ET2CNTLH2R = (uint8_t)((hw_cnt >> 16) & 0xff);
timer2_reg->ET2CNTLHR = (uint8_t)((hw_cnt >> 8) & 0xff);
timer2_reg->ET2CNTLLR = (uint8_t)(hw_cnt & 0xff);
irq_enable(ONE_SHOT_TIMER_IRQ);
}
#endif /* CONFIG_SOC_IT8XXX2_PLL_FLASH_48M */
static void evt_timer_isr(const void *unused)
{
ARG_UNUSED(unused);
/* Disable event timer */
IT8XXX2_EXT_CTRLX(EVENT_TIMER) &= ~IT8XXX2_EXT_ETXEN;
/* W/C event timer interrupt status */
ite_intc_isr_clear(EVENT_TIMER_IRQ);
if (IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
/*
* Get free run observer count from last time announced and
* trnaform unit to system tick
*/
uint32_t dticks = (~(IT8XXX2_EXT_CNTOX(FREE_RUN_TIMER)) -
last_announced_hw_cnt) / HW_CNT_PER_SYS_TICK;
last_announced_hw_cnt += (dticks * HW_CNT_PER_SYS_TICK);
sys_clock_announce(dticks);
} else {
/* Enable and re-start event timer */
IT8XXX2_EXT_CTRLX(EVENT_TIMER) |= (IT8XXX2_EXT_ETXEN |
IT8XXX2_EXT_ETXRST);
/* Informs kernel that one system tick has elapsed */
sys_clock_announce(1);
}
}
void sys_clock_set_timeout(int32_t ticks, bool idle)
{
uint32_t hw_cnt;
ARG_UNUSED(idle);
if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
/* Always return for non-tickless kernel system */
return;
}
/* Critical section */
k_spinlock_key_t key = k_spin_lock(&lock);
/* Disable event timer */
IT8XXX2_EXT_CTRLX(EVENT_TIMER) &= ~IT8XXX2_EXT_ETXEN;
if (ticks == K_TICKS_FOREVER) {
/* Return since no future timer interrupts are required */
k_spin_unlock(&lock, key);
return;
} else if (ticks <= 1) {
/*
* Ticks <= 1 means the kernel wants the tick announced
* as soon as possible, ideally no more than one system tick
* in the future. So set event timer count to 1 system tick or
* at least 1 hw count.
*/
hw_cnt = MAX((1 * HW_CNT_PER_SYS_TICK), 1);
} else {
if (ticks > EVEN_TIMER_MAX_CNT_SYS_TICK)
/*
* Set event timer count to EVENT_TIMER_MAX_CNT, after
* interrupt fired the remaining time will be set again
* by sys_clock_announce().
*/
hw_cnt = EVENT_TIMER_MAX_CNT;
else
/*
* Set event timer count to system tick or at least
* 1 hw count
*/
hw_cnt = MAX((ticks * HW_CNT_PER_SYS_TICK), 1);
}
/* Set event timer 24-bit count */
IT8XXX2_EXT_CNTX(EVENT_TIMER) = hw_cnt;
/* W/C event timer interrupt status */
ite_intc_isr_clear(EVENT_TIMER_IRQ);
/*
* When timer enable bit is from 0->1, timer will reload counts and
* start countdown.
*/
IT8XXX2_EXT_CTRLX(EVENT_TIMER) |= IT8XXX2_EXT_ETXEN;
k_spin_unlock(&lock, key);
LOG_DBG("timeout is 0x%x, set hw count 0x%x", ticks, hw_cnt);
}
uint32_t sys_clock_elapsed(void)
{
if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
/* Always return 0 for non-tickless kernel system */
return 0;
}
/* Critical section */
k_spinlock_key_t key = k_spin_lock(&lock);
/*
* Get free run observer count from last time announced and trnaform
* unit to system tick
*/
uint32_t dticks = (~(IT8XXX2_EXT_CNTOX(FREE_RUN_TIMER)) -
last_announced_hw_cnt) / HW_CNT_PER_SYS_TICK;
k_spin_unlock(&lock, key);
return dticks;
}
uint32_t sys_clock_cycle_get_32(void)
{
/*
* Get free run observer count and trnaform unit to system tick
*
* NOTE: Timer is counting down from 0xffffffff. In not combined
* mode, the observer count value is the same as count, so after
* NOT count operation we can get counting up value; In
* combined mode, the observer count value is the same as NOT
* count operation.
*/
uint32_t dticks = (~(IT8XXX2_EXT_CNTOX(FREE_RUN_TIMER)))
/ HW_CNT_PER_SYS_TICK;
return dticks;
}
static int timer_init(enum ext_timer_idx ext_timer,
enum ext_clk_src_sel clock_source_sel,
uint32_t raw,
uint32_t ms,
uint8_t first_time_enable,
uint32_t irq_num,
uint32_t irq_flag,
uint8_t with_int,
uint8_t start)
{
uint32_t hw_cnt;
if (raw) {
hw_cnt = ms;
} else {
if (clock_source_sel == EXT_PSR_32P768K)
hw_cnt = MS_TO_COUNT(32768, ms);
else if (clock_source_sel == EXT_PSR_1P024K)
hw_cnt = MS_TO_COUNT(1024, ms);
else if (clock_source_sel == EXT_PSR_32)
hw_cnt = MS_TO_COUNT(32, ms);
else if (clock_source_sel == EXT_PSR_8M)
hw_cnt = 8000 * ms;
else {
LOG_ERR("Timer %d clock source error !", ext_timer);
return -1;
}
}
if (hw_cnt == 0) {
LOG_ERR("Timer %d count shouldn't be 0 !", ext_timer);
return -1;
}
if (first_time_enable) {
/* Enable and re-start external timer x */
IT8XXX2_EXT_CTRLX(ext_timer) |= (IT8XXX2_EXT_ETXEN |
IT8XXX2_EXT_ETXRST);
/* Disable external timer x */
IT8XXX2_EXT_CTRLX(ext_timer) &= ~IT8XXX2_EXT_ETXEN;
}
/* Set rising edge triggered of external timer x */
ite_intc_irq_priority_set(irq_num, 0, irq_flag);
/* Clear interrupt status of external timer x */
ite_intc_isr_clear(irq_num);
/* Set clock source of external timer x */
IT8XXX2_EXT_PSRX(ext_timer) = clock_source_sel;
/* Set count of external timer x */
IT8XXX2_EXT_CNTX(ext_timer) = hw_cnt;
/* Disable external timer x */
IT8XXX2_EXT_CTRLX(ext_timer) &= ~IT8XXX2_EXT_ETXEN;
if (start)
/* Enable and re-start external timer x */
IT8XXX2_EXT_CTRLX(ext_timer) |= (IT8XXX2_EXT_ETXEN |
IT8XXX2_EXT_ETXRST);
if (with_int)
irq_enable(irq_num);
else
irq_disable(irq_num);
return 0;
}
int sys_clock_driver_init(const struct device *dev)
{
int ret;
ARG_UNUSED(dev);
/* Set 32-bit timer4 for free run*/
ret = timer_init(FREE_RUN_TIMER, EXT_PSR_32P768K, TRUE,
FREE_RUN_TIMER_MAX_CNT, TRUE, FREE_RUN_TIMER_IRQ,
FREE_RUN_TIMER_FLAG, FALSE, TRUE);
if (ret < 0) {
LOG_ERR("Init free run timer failed");
return ret;
}
/* Set 24-bit timer3 for timeout event */
IRQ_CONNECT(EVENT_TIMER_IRQ, 0, evt_timer_isr, NULL, EVENT_TIMER_FLAG);
if (IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
ret = timer_init(EVENT_TIMER, EXT_PSR_32P768K, TRUE,
EVENT_TIMER_MAX_CNT, TRUE, EVENT_TIMER_IRQ,
EVENT_TIMER_FLAG, TRUE, FALSE);
} else {
/* Start a event timer in one system tick */
ret = timer_init(EVENT_TIMER, EXT_PSR_32P768K, TRUE,
MAX((1 * HW_CNT_PER_SYS_TICK), 1), TRUE,
EVENT_TIMER_IRQ, EVENT_TIMER_FLAG,
TRUE, TRUE);
}
if (ret < 0) {
LOG_ERR("Init event timer failed");
return ret;
}
return 0;
}