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 SPRN_DSCR       0x11    /* Privilege state SPR */
  32 #define SPRN_DSCR_USR   0x03    /* Problem state SPR */
  33 #define THREADS         100     /* Max threads */
  34 #define COUNT           100     /* Max iterations */
  35 #define DSCR_MAX        16      /* Max DSCR value */
  36 #define LEN_MAX         100     /* Max name length */
  37
  38 #define DSCR_DEFAULT    "/sys/devices/system/cpu/dscr_default"
  39 #define CPU_PATH        "/sys/devices/system/cpu/"
  40
  41 #define rmb()  asm volatile("lwsync":::"memory")
  42 #define wmb()  asm volatile("lwsync":::"memory")
  43
  44 #define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
  45
  46 /* Prilvilege state DSCR access */
  47 inline unsigned long get_dscr(void)
  48 {
  49         unsigned long ret;
  50
  51         asm volatile("mfspr %0,%1" : "=r" (ret): "i" (SPRN_DSCR));
  52
  53         return ret;
  54 }
  55
  56 inline void set_dscr(unsigned long val)
  57 {
  58         asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
  59 }
  60
  61 /* Problem state DSCR access */
  62 inline unsigned long get_dscr_usr(void)
  63 {
  64         unsigned long ret;
  65
  66         asm volatile("mfspr %0,%1" : "=r" (ret): "i" (SPRN_DSCR_USR));
  67
  68         return ret;
  69 }
  70
  71 inline void set_dscr_usr(unsigned long val)
  72 {
  73         asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR_USR));
  74 }
  75
  76 /* Default DSCR access */
  77 unsigned long get_default_dscr(void)
  78 {
  79         int fd = -1, ret;
  80         char buf[16];
  81         unsigned long val;
  82
  83         if (fd == -1) {
  84                 fd = open(DSCR_DEFAULT, O_RDONLY);
  85                 if (fd == -1) {
  86                         perror("open() failed");
  87                         exit(1);
  88                 }
  89         }
  90         memset(buf, 0, sizeof(buf));
  91         lseek(fd, 0, SEEK_SET);
  92         ret = read(fd, buf, sizeof(buf));
  93         if (ret == -1) {
  94                 perror("read() failed");
  95                 exit(1);
  96         }
  97         sscanf(buf, "%lx", &val);
  98         close(fd);
  99         return val;
 100 }
 101
 102 void set_default_dscr(unsigned long val)
 103 {
 104         int fd = -1, ret;
 105         char buf[16];
 106
 107         if (fd == -1) {
 108                 fd = open(DSCR_DEFAULT, O_RDWR);
 109                 if (fd == -1) {
 110                         perror("open() failed");
 111                         exit(1);
 112                 }
 113         }
 114         sprintf(buf, "%lx\n", val);
 115         ret = write(fd, buf, strlen(buf));
 116         if (ret == -1) {
 117                 perror("write() failed");
 118                 exit(1);
 119         }
 120         close(fd);
 121 }
 122
 123 double uniform_deviate(int seed)
 124 {
 125         return seed * (1.0 / (RAND_MAX + 1.0));
 126 }
 127 #endif  /* _SELFTESTS_POWERPC_DSCR_DSCR_H */