efi-boot-shim/include/asm.h
2024-05-03 16:02:10 +01:00

57 lines
1.4 KiB
C

// SPDX-License-Identifier: BSD-2-Clause-Patent
#ifndef SHIM_ASM_H_
#define SHIM_ASM_H_
#define __stringify_1(x...) #x
#define __stringify(x...) __stringify_1(x)
static inline uint64_t read_counter(void)
{
uint64_t val;
#if defined (__x86_64__)
unsigned long low, high;
__asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high));
val = (low) | (high) << 32;
#elif defined(__i386__) || defined(__i686__)
__asm__ __volatile__("rdtsc" : "=A" (val));
#elif defined(__aarch64__)
__asm__ __volatile__ ("mrs %0, pmccntr_el0" : "=r" (val));
#elif defined(__arm__)
__asm__ __volatile__ ("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
#else
#error unsupported arch
#endif
return val;
}
#if defined(__x86_64__) || defined(__i386__) || defined(__i686__)
static inline void wait_for_debug(void)
{
__asm__ __volatile__("pause");
}
#elif defined(__aarch64__)
static inline void wait_for_debug(void)
{
__asm__ __volatile__("wfi");
}
#else
static inline void wait_for_debug(void)
{
uint64_t a, b;
int x;
extern void usleep(unsigned long usecs);
a = read_counter();
for (x = 0; x < 1000; x++) {
usleep(1000);
b = read_counter();
if (a != b)
break;
}
}
#endif
#endif /* !SHIM_ASM_H_ */
// vim:fenc=utf-8:tw=75:et