cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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tsc.c (498B)

      1// SPDX-License-Identifier: GPL-2.0
      2
      3#include <linux/types.h>
      4
      5#include "../../../util/tsc.h"
      6
      7u64 rdtsc(void)
      8{
      9	u64 val;
     10
     11	/*
     12	 * According to ARM DDI 0487F.c, from Armv8.0 to Armv8.5 inclusive, the
     13	 * system counter is at least 56 bits wide; from Armv8.6, the counter
     14	 * must be 64 bits wide.  So the system counter could be less than 64
     15	 * bits wide and it is attributed with the flag 'cap_user_time_short'
     16	 * is true.
     17	 */
     18	asm volatile("mrs %0, cntvct_el0" : "=r" (val));
     19
     20	return val;
     21}