tools/testing/selftests/powerpc/dscr/dscr.h

   1 /*
   2  * POWER Data Stream Control Register (DSCR)
   3  *
   4  * This header file contains helper functions and macros
   5  * required for all the DSCR related test cases.
   6  *
   7  * Copyright 2012, Anton Blanchard, IBM Corporation.
   8  * Copyright 2015, Anshuman Khandual, IBM Corporation.
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License version 2 as published
  12  * by the Free Software Foundation.
  13  */
  14 #ifndef _SELFTESTS_POWERPC_DSCR_DSCR_H
  15 #define _SELFTESTS_POWERPC_DSCR_DSCR_H
  16
  17 #include <unistd.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <fcntl.h>
  22 #include <dirent.h>
  23 #include <pthread.h>
  24 #include <sched.h>
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <sys/wait.h>
  28
  29 #include "utils.h"
  30
  31 #define THREADS         100     /* Max threads */
  32 #define COUNT           100     /* Max iterations */
  33 #define DSCR_MAX        16      /* Max DSCR value */
  34 #define LEN_MAX         100     /* Max name length */
  35
  36 #define DSCR_DEFAULT    "/sys/devices/system/cpu/dscr_default"
  37 #define CPU_PATH        "/sys/devices/system/cpu/"
  38
  39 #define rmb()  asm volatile("lwsync":::"memory")
  40 #define wmb()  asm volatile("lwsync":::"memory")
  41
  42 #define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
  43
  44 /* Prilvilege state DSCR access */
  45 inline unsigned long get_dscr(void)
  46 {
  47         unsigned long ret;
  48
  49         asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR_PRIV));
  50
  51         return ret;
  52 }
  53
  54 inline void set_dscr(unsigned long val)
  55 {
  56         asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR_PRIV));
  57 }
  58
  59 /* Problem state DSCR access */
  60 inline unsigned long get_dscr_usr(void)
  61 {
  62         unsigned long ret;
  63
  64         asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR));
  65
  66         return ret;
  67 }
  68
  69 inline void set_dscr_usr(unsigned long val)
  70 {
  71         asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
  72 }
  73
  74 /* Default DSCR access */
  75 unsigned long get_default_dscr(void)
  76 {
  77         int fd = -1, ret;
  78         char buf[16];
  79         unsigned long val;
  80
  81         if (fd == -1) {
  82                 fd = open(DSCR_DEFAULT, O_RDONLY);
  83                 if (fd == -1) {
  84                         perror("open() failed");
  85                         exit(1);
  86                 }
  87         }
  88         memset(buf, 0, sizeof(buf));
  89         lseek(fd, 0, SEEK_SET);
  90         ret = read(fd, buf, sizeof(buf));
  91         if (ret == -1) {
  92                 perror("read() failed");
  93                 exit(1);
  94         }
  95         sscanf(buf, "%lx", &val);
  96         close(fd);
  97         return val;
  98 }
  99
 100 void set_default_dscr(unsigned long val)
 101 {
 102         int fd = -1, ret;
 103         char buf[16];
 104
 105         if (fd == -1) {
 106                 fd = open(DSCR_DEFAULT, O_RDWR);
 107                 if (fd == -1) {
 108                         perror("open() failed");
 109                         exit(1);
 110                 }
 111         }
 112         sprintf(buf, "%lx\n", val);
 113         ret = write(fd, buf, strlen(buf));
 114         if (ret == -1) {
 115                 perror("write() failed");
 116                 exit(1);
 117         }
 118         close(fd);
 119 }
 120
 121 double uniform_deviate(int seed)
 122 {
 123         return seed * (1.0 / (RAND_MAX + 1.0));
 124 }
 125 #endif  /* _SELFTESTS_POWERPC_DSCR_DSCR_H */