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[M2351] Refine wait_ns(...) code 

1.  Add missing header file for mbed_mpu_manager_lock_ram_execution()/
    mbed_mpu_manager_unlock_ram_execution() to avoid compile warning.
2.  Locate delay_loop_code() on 16-byte boundary (sync to common version).
3.  Optimize delay_loop macro (sync to common version).
pull/11019/head
Chun-Chieh Li 2019-07-08 17:20:32 +08:00
parent 492d10cb3e
commit a03985ea43
1 changed files with 3 additions and 2 deletions
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5
targets/TARGET_NUVOTON/TARGET_M2351/TARGET_M23_NS/wait_ns.c
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@ -17,6 +17,7 @@
*/
#include "cmsis.h"
#include "platform/mbed_mpu_mgmt.h"
#include "platform/mbed_toolchain.h"
#include "platform/mbed_wait_api.h"
@ -36,7 +37,7 @@
// Cortex-M0+, M3, M4 and M23 take 5 cycles per iteration - SUBS = 1, 2xNOP = 2, BCS = 2
#define LOOP_SCALER 5000
MBED_ALIGN(8)
MBED_ALIGN(16)
static uint16_t delay_loop_code[] = {
0x1E40, // SUBS R0,R0,#1
0xBF00, // NOP
@ -46,7 +47,7 @@ static uint16_t delay_loop_code[] = {
};
/* Take the address of the code, set LSB to indicate Thumb, and cast to void() function pointer */
#define delay_loop ((void(*)()) ((uintptr_t) delay_loop_code | 1))
#define delay_loop ((void(*)()) ((uintptr_t) delay_loop_code + 1))
void wait_ns(unsigned int ns)
{