#include "clock.h"
#include "gd32f3x0.h"

extern uint32_t SystemCoreClock;
static u8 delay_ticks_enable = 0;
void delay_us(uint32_t us){
	if (delay_ticks_enable) {
		task_udelay(us);
		return;
	}
	uint32_t insr_num = (SystemCoreClock /1000000) * us * 4;// 1000000;
	while(insr_num-->0); //have 4 instr
}

void task_ticks_enable(void)
{
	CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
	DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;
	delay_ticks_enable = 1;
}

u32 task_ticks_abs(void)
{
	return DWT->CYCCNT;
}

u32 task_ticks_rel(u32 start)
{
	u32 ticks = DWT->CYCCNT;

	if (ticks >= start) {
		return ticks - start;
	}

	return 0xFFFFFFFF - start + ticks + 1;
}

void task_ticks_delay(u32 ticks)
{
	u32 start;

	start = task_ticks_abs();
	while (task_ticks_rel(start) < ticks);
}

void task_udelay(u32 delay)
{
	task_ticks_delay(delay * (SystemCoreClock / 1000000));
}


uint32_t get_sys_clock(void){
	return SystemCoreClock;
}
uint32_t get_ahb_clock(void){
	return rcu_clock_freq_get(CK_AHB);	
}
uint32_t get_apb1_clock(void){
	return rcu_clock_freq_get(CK_APB1);	
}
uint32_t get_apb2_clock(void){
	return rcu_clock_freq_get(CK_APB2); 
}

uint32_t get_adc_clock(void){
	return rcu_clock_freq_get(CK_ADC); 
}

uint32_t get_apb1_timer_clock(void){
    uint32_t apb1psc = 0U;
    apb1psc = RCU_CFG0;
	uint32_t div = GET_BITS(apb1psc, 8, 10);
	if (div == 0){ //DIV1
		return get_apb1_clock();
	}
	return get_apb1_clock() * 2;
}
uint32_t get_apb2_timer_clock(void){
    uint32_t apb2psc = 0U;
    apb2psc = RCU_CFG0;
	uint32_t div = GET_BITS(apb2psc, 11, 13);
	if (div == 0){ //DIV1
		return get_apb2_clock();
	}
	return get_apb2_clock() * 2;
}