linux/tools/testing/selftests/powerpc/dscr/dscr_user_test.c
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   1/*
   2 * POWER Data Stream Control Register (DSCR) SPR test
   3 *
   4 * This test modifies the DSCR value through both the SPR number
   5 * based mtspr instruction and then makes sure that the same is
   6 * reflected through mfspr instruction using either of the SPR
   7 * numbers.
   8 *
   9 * When using the privilege state SPR, the instructions such as
  10 * mfspr or mtspr are priviledged and the kernel emulates them
  11 * for us. Instructions using problem state SPR can be exuecuted
  12 * directly without any emulation if the HW supports them. Else
  13 * they also get emulated by the kernel.
  14 *
  15 * Copyright 2013, Anton Blanchard, IBM Corporation.
  16 * Copyright 2015, Anshuman Khandual, IBM Corporation.
  17 *
  18 * This program is free software; you can redistribute it and/or modify it
  19 * under the terms of the GNU General Public License version 2 as published
  20 * by the Free Software Foundation.
  21 */
  22#include "dscr.h"
  23
  24static int check_dscr(char *str)
  25{
  26        unsigned long cur_dscr, cur_dscr_usr;
  27
  28        cur_dscr = get_dscr();
  29        cur_dscr_usr = get_dscr_usr();
  30        if (cur_dscr != cur_dscr_usr) {
  31                printf("%s set, kernel get %lx != user get %lx\n",
  32                                        str, cur_dscr, cur_dscr_usr);
  33                return 1;
  34        }
  35        return 0;
  36}
  37
  38int dscr_user(void)
  39{
  40        int i;
  41
  42        check_dscr("");
  43
  44        for (i = 0; i < COUNT; i++) {
  45                set_dscr(i);
  46                if (check_dscr("kernel"))
  47                        return 1;
  48        }
  49
  50        for (i = 0; i < COUNT; i++) {
  51                set_dscr_usr(i);
  52                if (check_dscr("user"))
  53                        return 1;
  54        }
  55        return 0;
  56}
  57
  58int main(int argc, char *argv[])
  59{
  60        return test_harness(dscr_user, "dscr_user_test");
  61}
  62