cpu cycles: on arm64 use clock_gettime and PMCCNTR_EL0 for freestanding #238
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previously, cntvct_el0 was used which is capped to 24 MHz, leading to entropy test failures on macOS and linux-aarch64. The PMCCNTR_EL0 is not available in user-space normally (for Linux, there is a kernel module). So, what we do is similar to the ARM32 code path now. Fixes mirage#216
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doesn't work. |
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previously, cntvct_el0 was used which is capped to 24 MHz, leading to entropy test failures on macOS and linux-aarch64. The PMCCNTR_EL0 is not available in user-space normally (for Linux, there is a kernel module).
So, what we do is similar to the ARM32 code path now.
Fixes #216