tests/tcg/aarch64/system/vtimer.c

   1 /*
   2  * Simple Virtual Timer Test
   3  *
   4  * Copyright (c) 2020 Linaro Ltd
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 #include <stdint.h>
  10 #include <minilib.h>
  11
  12 /* grabbed from Linux */
  13 #define __stringify_1(x...) #x
  14 #define __stringify(x...)   __stringify_1(x)
  15
  16 #define read_sysreg(r) ({                                           \
  17             uint64_t __val;                                         \
  18             asm volatile("mrs %0, " __stringify(r) : "=r" (__val)); \
  19             __val;                                                  \
  20 })
  21
  22 #define write_sysreg(r, v) do {                     \
  23         uint64_t __val = (uint64_t)(v);             \
  24         asm volatile("msr " __stringify(r) ", %x0"  \
  25                  : : "rZ" (__val));                 \
  26 } while (0)
  27
  28 int main(void)
  29 {
  30     int i;
  31
  32     ml_printf("VTimer Test\n");
  33
  34     write_sysreg(cntvoff_el2, 1);
  35     write_sysreg(cntv_cval_el0, -1);
  36     write_sysreg(cntv_ctl_el0, 1);
  37
  38     ml_printf("cntvoff_el2=%lx\n", read_sysreg(cntvoff_el2));
  39     ml_printf("cntv_cval_el0=%lx\n", read_sysreg(cntv_cval_el0));
  40     ml_printf("cntv_ctl_el0=%lx\n", read_sysreg(cntv_ctl_el0));
  41
  42     /* Now read cval a few times */
  43     for (i = 0; i < 10; i++) {
  44         ml_printf("%d: cntv_cval_el0=%lx\n", i, read_sysreg(cntv_cval_el0));
  45     }
  46
  47     return 0;
  48 }