LXR linux/tools/testing/selftests/arm64/fp/sve-probe-vls.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2015-2020 ARM Limited.
   4 * Original author: Dave Martin <Dave.Martin@arm.com>
   5 */
   6#include <assert.h>
   7#include <errno.h>
   8#include <stdio.h>
   9#include <stdlib.h>
  10#include <string.h>
  11#include <sys/auxv.h>
  12#include <sys/prctl.h>
  13#include <asm/sigcontext.h>
  14
  15#include "../../kselftest.h"
  16#include "rdvl.h"
  17
  18int main(int argc, char **argv)
  19{
  20        unsigned int vq;
  21        int vl;
  22        static unsigned int vqs[SVE_VQ_MAX];
  23        unsigned int nvqs = 0;
  24
  25        ksft_print_header();
  26        ksft_set_plan(2);
  27
  28        if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
  29                ksft_exit_skip("SVE not available\n");
  30
  31        /*
  32         * Enumerate up to SVE_VQ_MAX vector lengths
  33         */
  34        for (vq = SVE_VQ_MAX; vq > 0; --vq) {
  35                vl = prctl(PR_SVE_SET_VL, vq * 16);
  36                if (vl == -1)
  37                        ksft_exit_fail_msg("PR_SVE_SET_VL failed: %s (%d)\n",
  38                                           strerror(errno), errno);
  39
  40                vl &= PR_SVE_VL_LEN_MASK;
  41
  42                if (rdvl_sve() != vl)
  43                        ksft_exit_fail_msg("PR_SVE_SET_VL reports %d, RDVL %d\n",
  44                                           vl, rdvl_sve());
  45
  46                if (!sve_vl_valid(vl))
  47                        ksft_exit_fail_msg("VL %d invalid\n", vl);
  48                vq = sve_vq_from_vl(vl);
  49
  50                if (!(nvqs < SVE_VQ_MAX))
  51                        ksft_exit_fail_msg("Too many VLs %u >= SVE_VQ_MAX\n",
  52                                           nvqs);
  53                vqs[nvqs++] = vq;
  54        }
  55        ksft_test_result_pass("Enumerated %d vector lengths\n", nvqs);
  56        ksft_test_result_pass("All vector lengths valid\n");
  57
  58        /* Print out the vector lengths in ascending order: */
  59        while (nvqs--)
  60                ksft_print_msg("%u\n", 16 * vqs[nvqs]);
  61
  62        ksft_exit_pass();
  63}
  64