bool timer_set(long cycles, bool start)
{
unsigned int divider = cycles, prescaler_bit = 0, prescaler = 1, old_irq;
if(cycles < 1)
return false;
if(start && pfn_unregister != NULL)
{
pfn_unregister();
pfn_unregister = NULL;
}
/* Increase prescale values starting from 0 to make the cycle count fit */
while(divider > 65535 && prescaler <= 1024)
{
prescaler <<= 2; /* 1, 4, 16, 64, 256, 1024 */
prescaler_bit++;
divider = cycles / prescaler;
}
old_irq = disable_irq_save();
__tcu_stop_counter(1);
if(start)
{
__tcu_disable_pwm_output(1);
__tcu_mask_half_match_irq(1);
__tcu_unmask_full_match_irq(1);
/* EXTAL clock = CFG_EXTAL (12Mhz in most targets) */
__tcu_select_extalclk(1);
}
REG_TCU_TCSR(1) = (REG_TCU_TCSR(1) & ~TCU_TCSR_PRESCALE_MASK) | (prescaler_bit << TCU_TCSR_PRESCALE_BIT);
REG_TCU_TCNT(1) = 0;
REG_TCU_TDHR(1) = 0;
REG_TCU_TDFR(1) = divider;
__tcu_clear_full_match_flag(1);
if(start)
{
system_enable_irq(IRQ_TCU1);
__tcu_start_counter(1);
}
restore_irq(old_irq);
return true;
}
bool _backlight_init(void)
{
__gpio_as_pwm(BACKLIGHT_PWM);
__tcu_start_timer_clock(BACKLIGHT_PWM);
__tcu_stop_counter(BACKLIGHT_PWM);
__tcu_init_pwm_output_low(BACKLIGHT_PWM);
__tcu_set_pwm_output_shutdown_graceful(BACKLIGHT_PWM);
__tcu_disable_pwm_output(BACKLIGHT_PWM);
__tcu_select_extalclk(BACKLIGHT_PWM); /* 12 MHz */
__tcu_select_clk_div64(BACKLIGHT_PWM); /* 187.5 kHz */
__tcu_mask_half_match_irq(BACKLIGHT_PWM);
__tcu_mask_full_match_irq(BACKLIGHT_PWM);
__tcu_set_count(BACKLIGHT_PWM, 0);
__tcu_set_half_data(BACKLIGHT_PWM, 0);
__tcu_set_full_data(BACKLIGHT_PWM, 256);
return true;
}
void mdelay (unsigned int ms) {
int i;
__tcu_disable_pwm_output(3);
__tcu_mask_half_match_irq(3);
__tcu_mask_full_match_irq(3);
__tcu_select_extalclk(3);
__tcu_select_clk_div16(3);
REG_TCU_TDFR(3) = CFG_EXTAL / 16 / 1000;
REG_TCU_TDHR(3) = CFG_EXTAL / 16 / 1000;
__tcu_set_count(3, 0);
__tcu_start_counter(3);
for (i = 0; i < ms; i++) {
__tcu_clear_full_match_flag(3);
while (!__tcu_full_match_flag(3));
}
__tcu_stop_counter(3);
}
