Files
dragonpilot/panda/board/drivers/clock_source.h
2020-10-02 01:45:44 +00:00

100 lines
3.4 KiB
C

#define CLOCK_SOURCE_MODE_DISABLED 0U
#define CLOCK_SOURCE_MODE_FREE_RUNNING 1U
#define CLOCK_SOURCE_MODE_EXTERNAL_SYNC 2U
#define CLOCK_SOURCE_PERIOD_MS 50U
#define CLOCK_SOURCE_PULSE_LEN_MS 2U
uint8_t clock_source_mode = CLOCK_SOURCE_MODE_DISABLED;
void EXTI0_IRQ_Handler(void) {
volatile unsigned int pr = EXTI->PR & (1U << 0);
if (pr != 0U) {
if(clock_source_mode == CLOCK_SOURCE_MODE_EXTERNAL_SYNC){
// TODO: Implement!
}
}
EXTI->PR = (1U << 0);
}
void TIM1_UP_TIM10_IRQ_Handler(void) {
if((TIM1->SR & TIM_SR_UIF) != 0) {
if(clock_source_mode != CLOCK_SOURCE_MODE_DISABLED) {
// Start clock pulse
set_gpio_output(GPIOB, 14, true);
set_gpio_output(GPIOB, 15, true);
}
// Reset interrupt
TIM1->SR &= ~(TIM_SR_UIF);
}
}
void TIM1_CC_IRQ_Handler(void) {
if((TIM1->SR & TIM_SR_CC1IF) != 0) {
if(clock_source_mode != CLOCK_SOURCE_MODE_DISABLED) {
// End clock pulse
set_gpio_output(GPIOB, 14, false);
set_gpio_output(GPIOB, 15, false);
}
// Reset interrupt
TIM1->SR &= ~(TIM_SR_CC1IF);
}
}
void clock_source_init(uint8_t mode){
// Setup external clock signal interrupt
REGISTER_INTERRUPT(EXTI0_IRQn, EXTI0_IRQ_Handler, 110U, FAULT_INTERRUPT_RATE_CLOCK_SOURCE)
register_set(&(SYSCFG->EXTICR[0]), SYSCFG_EXTICR1_EXTI0_PB, 0xFU);
register_set_bits(&(EXTI->IMR), (1U << 0));
register_set_bits(&(EXTI->RTSR), (1U << 0));
register_clear_bits(&(EXTI->FTSR), (1U << 0));
// Setup timer
REGISTER_INTERRUPT(TIM1_UP_TIM10_IRQn, TIM1_UP_TIM10_IRQ_Handler, (1200U / CLOCK_SOURCE_PERIOD_MS) , FAULT_INTERRUPT_RATE_TIM1)
REGISTER_INTERRUPT(TIM1_CC_IRQn, TIM1_CC_IRQ_Handler, (1200U / CLOCK_SOURCE_PERIOD_MS) , FAULT_INTERRUPT_RATE_TIM1)
register_set(&(TIM1->PSC), (9600-1), 0xFFFFU); // Tick on 0.1 ms
register_set(&(TIM1->ARR), ((CLOCK_SOURCE_PERIOD_MS*10U) - 1U), 0xFFFFU); // Period
register_set(&(TIM1->CCMR1), 0U, 0xFFFFU); // No output on compare
register_set_bits(&(TIM1->CCER), TIM_CCER_CC1E); // Enable compare 1
register_set(&(TIM1->CCR1), (CLOCK_SOURCE_PULSE_LEN_MS*10U), 0xFFFFU); // Compare 1 value
register_set_bits(&(TIM1->DIER), TIM_DIER_UIE | TIM_DIER_CC1IE); // Enable interrupts
register_set(&(TIM1->CR1), TIM_CR1_CEN, 0x3FU); // Enable timer
// Set mode
switch(mode) {
case CLOCK_SOURCE_MODE_DISABLED:
// No clock signal
NVIC_DisableIRQ(EXTI0_IRQn);
NVIC_DisableIRQ(TIM1_UP_TIM10_IRQn);
NVIC_DisableIRQ(TIM1_CC_IRQn);
// Disable pulse if we were in the middle of it
set_gpio_output(GPIOB, 14, false);
set_gpio_output(GPIOB, 15, false);
clock_source_mode = CLOCK_SOURCE_MODE_DISABLED;
break;
case CLOCK_SOURCE_MODE_FREE_RUNNING:
// Clock signal is based on internal timer
NVIC_DisableIRQ(EXTI0_IRQn);
NVIC_EnableIRQ(TIM1_UP_TIM10_IRQn);
NVIC_EnableIRQ(TIM1_CC_IRQn);
clock_source_mode = CLOCK_SOURCE_MODE_FREE_RUNNING;
break;
case CLOCK_SOURCE_MODE_EXTERNAL_SYNC:
// Clock signal is based on external timer
NVIC_EnableIRQ(EXTI0_IRQn);
NVIC_EnableIRQ(TIM1_UP_TIM10_IRQn);
NVIC_EnableIRQ(TIM1_CC_IRQn);
clock_source_mode = CLOCK_SOURCE_MODE_EXTERNAL_SYNC;
break;
default:
puts("Unknown clock source mode: "); puth(mode); puts("\n");
break;
}
}