diff options
| -rw-r--r-- | stmhal/modpyb.c | 18 | ||||
| -rw-r--r-- | stmhal/systick.c | 40 | ||||
| -rw-r--r-- | teensy/teensy_hal.h | 13 |
3 files changed, 32 insertions, 39 deletions
diff --git a/stmhal/modpyb.c b/stmhal/modpyb.c index e1d6d98bba..09a8caf278 100644 --- a/stmhal/modpyb.c +++ b/stmhal/modpyb.c @@ -198,11 +198,10 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_sync_obj, pyb_sync); /// always get the right answer and not have to worry about whether pyb.millis() /// wraps around. STATIC mp_obj_t pyb_millis(void) { - // We want to "cast" the 32 bit unsigned into a small-int. So we shift it - // left by 1 to throw away the top bit, and then shift it right by one - // to sign extend. - mp_int_t val = HAL_GetTick() << 1; - return mp_obj_new_int(val >> 1); + // We want to "cast" the 32 bit unsigned into a small-int. This means + // copying the MSB down 1 bit (extending the sign down), which is + // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro. + return MP_OBJ_NEW_SMALL_INT(HAL_GetTick()); } STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_millis_obj, pyb_millis); @@ -219,11 +218,10 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_millis_obj, pyb_millis); /// always get the right answer and not have to worry about whether pyb.micros() /// wraps around. STATIC mp_obj_t pyb_micros(void) { - // We want to "cast" the 32 bit unsigned into a small-int. So we shift it - // left by 1 to throw away the top bit, and then shift it right by one - // to sign extend. - mp_int_t val = sys_tick_get_microseconds() << 1; - return mp_obj_new_int(val >> 1); + // We want to "cast" the 32 bit unsigned into a small-int. This means + // copying the MSB down 1 bit (extending the sign down), which is + // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro. + return MP_OBJ_NEW_SMALL_INT(sys_tick_get_microseconds()); } STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_micros_obj, pyb_micros); diff --git a/stmhal/systick.c b/stmhal/systick.c index 660b777fc0..b2381d08eb 100644 --- a/stmhal/systick.c +++ b/stmhal/systick.c @@ -51,29 +51,29 @@ void sys_tick_wait_at_least(uint32_t start_tick, uint32_t delay_ms) { // // We assume that HAL_GetTickis returns milliseconds. uint32_t sys_tick_get_microseconds(void) { - mp_int_t enabled = disable_irq(); + mp_uint_t irq_state = disable_irq(); uint32_t counter = SysTick->VAL; uint32_t milliseconds = HAL_GetTick(); uint32_t status = SysTick->CTRL; - enable_irq(enabled); + enable_irq(irq_state); - // It's still possible for the countflag bit to get set if the counter was - // reloaded between reading VAL and reading CTRL. With interrupts disabled - // it definitely takes less than 50 HCLK cycles between reading VAL and - // reading CTRL, so the test (counter > 50) is to cover the case where VAL - // is +ve and very close to zero, and the COUNTFLAG bit is also set. - if ((status & SysTick_CTRL_COUNTFLAG_Msk) && counter > 50) { - // This means that the HW reloaded VAL between the time we read VAL and the - // time we read CTRL, which implies that there is an interrupt pending - // to increment the tick counter. - milliseconds++; - } - uint32_t load = SysTick->LOAD; - counter = load - counter; // Convert from decrementing to incrementing + // It's still possible for the countflag bit to get set if the counter was + // reloaded between reading VAL and reading CTRL. With interrupts disabled + // it definitely takes less than 50 HCLK cycles between reading VAL and + // reading CTRL, so the test (counter > 50) is to cover the case where VAL + // is +ve and very close to zero, and the COUNTFLAG bit is also set. + if ((status & SysTick_CTRL_COUNTFLAG_Msk) && counter > 50) { + // This means that the HW reloaded VAL between the time we read VAL and the + // time we read CTRL, which implies that there is an interrupt pending + // to increment the tick counter. + milliseconds++; + } + uint32_t load = SysTick->LOAD; + counter = load - counter; // Convert from decrementing to incrementing - // ((load + 1) / 1000) is the number of counts per microsecond. - // - // counter / ((load + 1) / 1000) scales from the systick clock to microseconds - // and is the same thing as (counter * 1000) / (load + 1) - return milliseconds * 1000 + (counter * 1000) / (load + 1); + // ((load + 1) / 1000) is the number of counts per microsecond. + // + // counter / ((load + 1) / 1000) scales from the systick clock to microseconds + // and is the same thing as (counter * 1000) / (load + 1) + return milliseconds * 1000 + (counter * 1000) / (load + 1); } diff --git a/teensy/teensy_hal.h b/teensy/teensy_hal.h index ffbb70bcc3..53228951c2 100644 --- a/teensy/teensy_hal.h +++ b/teensy/teensy_hal.h @@ -5,7 +5,7 @@ void assert_failed(uint8_t* file, uint32_t line); #else #define assert_param(expr) ((void)0) -#endif /* USE_FULL_ASSERT */ +#endif /* USE_FULL_ASSERT */ #define FTM0 ((FTM_TypeDef *)&FTM0_SC) #define FTM1 ((FTM_TypeDef *)&FTM1_SC) @@ -113,25 +113,20 @@ typedef struct { #define GPIO_AF6_I2C1 6 #define GPIO_AF7_FTM1 7 - -__attribute__(( always_inline )) static inline void __WFI(void) -{ +__attribute__(( always_inline )) static inline void __WFI(void) { __asm volatile ("wfi"); } -__attribute__(( always_inline )) static inline uint32_t __get_PRIMASK(void) -{ +__attribute__(( always_inline )) static inline uint32_t __get_PRIMASK(void) { uint32_t result; __asm volatile ("MRS %0, primask" : "=r" (result)); return(result); } -__attribute__(( always_inline )) static inline void __set_PRIMASK(uint32_t priMask) -{ +__attribute__(( always_inline )) static inline void __set_PRIMASK(uint32_t priMask) { __asm volatile ("MSR primask, %0" : : "r" (priMask) : "memory"); } - uint32_t HAL_GetTick(void); void HAL_Delay(uint32_t Delay); |