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stmhal: Add raise_irq_pri and restore_irq_pri functions.

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These can be used to disable only certain interrupts, ones at or above
the given priority value.
This commit is contained in:
Damien George 2015-12-04 11:38:23 +00:00
parent add6f4556e
commit 95c9cc8114
1 changed files with 19 additions and 0 deletions
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19
stmhal/irq.h
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@ -34,6 +34,25 @@ static inline mp_uint_t query_irq(void) {
// enable_irq and disable_irq are defined inline in mpconfigport.h // enable_irq and disable_irq are defined inline in mpconfigport.h
// irqs with a priority value greater or equal to "pri" will be disabled
// "pri" should be between 1 and 15 inclusive
static inline uint32_t raise_irq_pri(uint32_t pri) {
uint32_t basepri = __get_BASEPRI();
// If non-zero, the processor does not process any exception with a
// priority value greater than or equal to BASEPRI.
// When writing to BASEPRI_MAX the write goes to BASEPRI only if either:
// - Rn is non-zero and the current BASEPRI value is 0
// - Rn is non-zero and less than the current BASEPRI value
pri <<= (8 - __NVIC_PRIO_BITS);
__ASM volatile ("msr basepri_max, %0" : : "r" (pri) : "memory");
return basepri;
}
// "basepri" should be the value returned from raise_irq_pri
static inline void restore_irq_pri(uint32_t basepri) {
__set_BASEPRI(basepri);
}
MP_DECLARE_CONST_FUN_OBJ(pyb_wfi_obj); MP_DECLARE_CONST_FUN_OBJ(pyb_wfi_obj);
MP_DECLARE_CONST_FUN_OBJ(pyb_disable_irq_obj); MP_DECLARE_CONST_FUN_OBJ(pyb_disable_irq_obj);
MP_DECLARE_CONST_FUN_OBJ(pyb_enable_irq_obj); MP_DECLARE_CONST_FUN_OBJ(pyb_enable_irq_obj);