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stmhal/systick: Make mp_hal_delay_ms release the GIL when sleeping.

This commit is contained in:
Damien George 2017-03-22 12:54:43 +11:00
parent 2e3fc77809
commit 3509e2d307
1 changed files with 5 additions and 12 deletions
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17
stmhal/systick.c
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@ -51,24 +51,17 @@ void HAL_Delay(uint32_t Delay) {
} }
// Core delay function that does an efficient sleep and may switch thread context. // Core delay function that does an efficient sleep and may switch thread context.
// Note: Upon entering this function we may or may not have the GIL. // If IRQs are enabled then we must have the GIL.
void mp_hal_delay_ms(mp_uint_t Delay) { void mp_hal_delay_ms(mp_uint_t Delay) {
if (query_irq() == IRQ_STATE_ENABLED) { if (query_irq() == IRQ_STATE_ENABLED) {
// IRQs enabled, so can use systick counter to do the delay // IRQs enabled, so can use systick counter to do the delay
uint32_t start = uwTick; uint32_t start = uwTick;
// Wraparound of tick is taken care of by 2's complement arithmetic. // Wraparound of tick is taken care of by 2's complement arithmetic.
while (uwTick - start < Delay) { while (uwTick - start < Delay) {
// Enter sleep mode, waiting for (at least) the SysTick interrupt. // This macro will execute the necessary idle behaviour. It may
mp_handle_pending(); // raise an exception, switch threads or enter sleep mode (waiting for
#if MICROPY_PY_THREAD // (at least) the SysTick interrupt).
if (pyb_thread_enabled) { MICROPY_EVENT_POLL_HOOK
pyb_thread_yield();
} else {
__WFI();
}
#else
__WFI();
#endif
} }
} else { } else {
// IRQs disabled, so need to use a busy loop for the delay. // IRQs disabled, so need to use a busy loop for the delay.