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

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * POWER Data Stream Control Register (DSCR)
   4 *
   5 * This header file contains helper functions and macros
   6 * required for all the DSCR related test cases.
   7 *
   8 * Copyright 2012, Anton Blanchard, IBM Corporation.
   9 * Copyright 2015, Anshuman Khandual, IBM Corporation.
  10 */
  11#ifndef _SELFTESTS_POWERPC_DSCR_DSCR_H
  12#define _SELFTESTS_POWERPC_DSCR_DSCR_H
  13
  14#include <unistd.h>
  15#include <stdio.h>
  16#include <stdlib.h>
  17#include <string.h>
  18#include <fcntl.h>
  19#include <dirent.h>
  20#include <pthread.h>
  21#include <sched.h>
  22#include <sys/types.h>
  23#include <sys/stat.h>
  24#include <sys/wait.h>
  25
  26#include "utils.h"
  27
  28#define THREADS         100     /* Max threads */
  29#define COUNT           100     /* Max iterations */
  30#define DSCR_MAX        16      /* Max DSCR value */
  31#define LEN_MAX         100     /* Max name length */
  32
  33#define DSCR_DEFAULT    "/sys/devices/system/cpu/dscr_default"
  34#define CPU_PATH        "/sys/devices/system/cpu/"
  35
  36#define rmb()  asm volatile("lwsync":::"memory")
  37#define wmb()  asm volatile("lwsync":::"memory")
  38
  39#define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
  40
  41/* Prilvilege state DSCR access */
  42inline unsigned long get_dscr(void)
  43{
  44        unsigned long ret;
  45
  46        asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR_PRIV));
  47
  48        return ret;
  49}
  50
  51inline void set_dscr(unsigned long val)
  52{
  53        asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR_PRIV));
  54}
  55
  56/* Problem state DSCR access */
  57inline unsigned long get_dscr_usr(void)
  58{
  59        unsigned long ret;
  60
  61        asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR));
  62
  63        return ret;
  64}
  65
  66inline void set_dscr_usr(unsigned long val)
  67{
  68        asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
  69}
  70
  71/* Default DSCR access */
  72unsigned long get_default_dscr(void)
  73{
  74        int fd = -1, ret;
  75        char buf[16];
  76        unsigned long val;
  77
  78        if (fd == -1) {
  79                fd = open(DSCR_DEFAULT, O_RDONLY);
  80                if (fd == -1) {
  81                        perror("open() failed");
  82                        exit(1);
  83                }
  84        }
  85        memset(buf, 0, sizeof(buf));
  86        lseek(fd, 0, SEEK_SET);
  87        ret = read(fd, buf, sizeof(buf));
  88        if (ret == -1) {
  89                perror("read() failed");
  90                exit(1);
  91        }
  92        sscanf(buf, "%lx", &val);
  93        close(fd);
  94        return val;
  95}
  96
  97void set_default_dscr(unsigned long val)
  98{
  99        int fd = -1, ret;
 100        char buf[16];
 101
 102        if (fd == -1) {
 103                fd = open(DSCR_DEFAULT, O_RDWR);
 104                if (fd == -1) {
 105                        perror("open() failed");
 106                        exit(1);
 107                }
 108        }
 109        sprintf(buf, "%lx\n", val);
 110        ret = write(fd, buf, strlen(buf));
 111        if (ret == -1) {
 112                perror("write() failed");
 113                exit(1);
 114        }
 115        close(fd);
 116}
 117
 118double uniform_deviate(int seed)
 119{
 120        return seed * (1.0 / (RAND_MAX + 1.0));
 121}
 122#endif  /* _SELFTESTS_POWERPC_DSCR_DSCR_H */
 123