tests/tcg/aarch64/sve-ioctls.c

   1 /*
   2  * SVE ioctls tests
   3  *
   4  * Test the SVE width setting ioctls work and provide a base for
   5  * testing the gdbstub.
   6  *
   7  * Copyright (c) 2019 Linaro Ltd
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11 #include <sys/prctl.h>
  12 #include <asm/hwcap.h>
  13 #include <stdio.h>
  14 #include <sys/auxv.h>
  15 #include <stdint.h>
  16 #include <stdlib.h>
  17
  18 #ifndef HWCAP_CPUID
  19 #define HWCAP_CPUID (1 << 11)
  20 #endif
  21
  22 #define SVE_MAX_QUADS  (2048 / 128)
  23 #define BYTES_PER_QUAD (128 / 8)
  24
  25 #define get_cpu_reg(id) ({                                      \
  26             unsigned long __val;                                \
  27             asm("mrs %0, "#id : "=r" (__val));                  \
  28             __val;                                              \
  29         })
  30
  31 static int do_sve_ioctl_test(void)
  32 {
  33     int i, res, init_vq;
  34
  35     res = prctl(PR_SVE_GET_VL, 0, 0, 0, 0);
  36     if (res < 0) {
  37         printf("FAILED to PR_SVE_GET_VL (%d)", res);
  38         return -1;
  39     }
  40     init_vq = res & PR_SVE_VL_LEN_MASK;
  41
  42     for (i = init_vq; i > 15; i /= 2) {
  43         printf("Checking PR_SVE_SET_VL=%d\n", i);
  44         res = prctl(PR_SVE_SET_VL, i, 0, 0, 0, 0);
  45         if (res < 0) {
  46             printf("FAILED to PR_SVE_SET_VL (%d)", res);
  47             return -1;
  48         }
  49         asm("index z0.b, #0, #1\n"
  50             ".global __sve_ld_done\n"
  51             "__sve_ld_done:\n"
  52             "mov z0.b, #0\n"
  53             : /* no outputs kept */
  54             : /* no inputs */
  55             : "memory", "z0");
  56     }
  57     printf("PASS\n");
  58     return 0;
  59 }
  60
  61 int main(int argc, char **argv)
  62 {
  63     /* we also need to probe for the ioctl support */
  64     if (getauxval(AT_HWCAP) & HWCAP_SVE) {
  65         return do_sve_ioctl_test();
  66     } else {
  67         printf("SKIP: no HWCAP_SVE on this system\n");
  68         return 0;
  69     }
  70 }