90 lines
2.2 KiB
C++

#include <sta/devices/stm32/delay.hpp>
#ifdef STA_PLATFORM_STM32
#include <sta/devices/stm32/hal.hpp>
#include <sta/devices/stm32/clocks.hpp>
#include <sta/debug/assert.hpp>
#include <sta/lang.hpp>
namespace sta
{
void delayMs(uint32_t ms)
{
HAL_Delay(ms);
}
} // namespace sta
#ifdef STA_STM32_DELAY_US_TIM
#ifndef HAL_TIM_MODULE_ENABLED
# error "STM32 HAL TIM module not enabled!"
#endif // HAL_TIM_MODULE_ENABLED
#include <tim.h>
namespace sta
{
uint32_t gDelayUsMul = 1;
bool isValidDelayUsTIM()
{
// Get PCLK multiplier for TIM clock
uint32_t pclkMul = 1;
switch (STA_STM32_DELAY_US_TIM.Init.ClockDivision)
{
case TIM_CLOCKDIVISION_DIV1:
pclkMul = 1;
break;
case TIM_CLOCKDIVISION_DIV2:
pclkMul = 2;
break;
case TIM_CLOCKDIVISION_DIV4:
pclkMul = 4;
break;
default:
STA_ASSERT(false);
STA_UNREACHABLE();
}
// Calculate TIM clock frequency
uint32_t clkFreq = pclkMul * STA_STM32_GET_HANDLE_PCLK_FREQ_FN(STA_STM32_DELAY_US_TIM)() * STA_STM32_GET_HANDLE_PCLK_TIM_PRESCALER(STA_STM32_DELAY_US_TIM);
// Calculate update frequency based on prescaler value
uint32_t prescaler = (STA_STM32_DELAY_US_TIM.Init.Prescaler) ? STA_STM32_DELAY_US_TIM.Init.Prescaler : 1;
uint32_t updateFreq = clkFreq / prescaler;
gDelayUsMul = updateFreq / 1000000;
// TIM must have at least microsecond precision (>= 1 MHz frequency)
return (updateFreq >= 1000000);
}
void delayUs(uint32_t us)
{
// Check if the specified timer is usable for microsecond delays.
STA_ASSERT(isValidDelayUsTIM());
// Save the current value of the counter.
uint32_t current = __HAL_TIM_GET_COUNTER(&STA_STM32_DELAY_US_TIM);
// Set the timer counter to zero to avoid overflows during delay-
__HAL_TIM_SET_COUNTER(&STA_STM32_DELAY_US_TIM, 0);
// Wait for the desired microseconds.
while (__HAL_TIM_GET_COUNTER(&STA_STM32_DELAY_US_TIM) < us * gDelayUsMul);
// Set the timer counter to the previous value and add the waited duration to it.
// This avoids collisions with code relying on timeUs measurements.
__HAL_TIM_SET_COUNTER(&STA_STM32_DELAY_US_TIM, current + us * gDelayUsMul);
}
} // namespace sta
#endif // STA_STM32_DELAY_US_TIM
#endif // STA_PLATFORM_STM32