text: /*
   * POWER Data Stream Control Register (DSCR)
   *
   * This header file contains helper functions and macros
   * required for all the DSCR related test cases.
   *
   * Copyright 2012, Anton Blanchard, IBM Corporation.
   * Copyright 2015, Anshuman Khandual, IBM Corporation.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   */
  #ifndef _SELFTESTS_POWERPC_DSCR_DSCR_H
  #define _SELFTESTS_POWERPC_DSCR_DSCR_H
  
  #include <unistd.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <fcntl.h>
  #include <dirent.h>
  #include <pthread.h>
  #include <sched.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <sys/wait.h>
  
  #include "utils.h"
  
  #define THREADS		100	/* Max threads */
  #define COUNT		100	/* Max iterations */
  #define DSCR_MAX	16	/* Max DSCR value */
  #define LEN_MAX		100	/* Max name length */
  
  #define DSCR_DEFAULT	"/sys/devices/system/cpu/dscr_default"
  #define CPU_PATH	"/sys/devices/system/cpu/"
  
  #define rmb()  asm volatile("lwsync":::"memory")
  #define wmb()  asm volatile("lwsync":::"memory")
  
  #define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
  
  /* Prilvilege state DSCR access */
  inline unsigned long get_dscr(void)
  {
  	unsigned long ret;
  
  	asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR_PRIV));
  
  	return ret;
  }
  
  inline void set_dscr(unsigned long val)
  {
  	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR_PRIV));
  }
  
  /* Problem state DSCR access */
  inline unsigned long get_dscr_usr(void)
  {
  	unsigned long ret;
  
  	asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR));
  
  	return ret;
  }
  
  inline void set_dscr_usr(unsigned long val)
  {
  	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
  }
  
  /* Default DSCR access */
  unsigned long get_default_dscr(void)
  {
  	int fd = -1, ret;
  	char buf[16];
  	unsigned long val;
  
  	if (fd == -1) {
  		fd = open(DSCR_DEFAULT, O_RDONLY);
  		if (fd == -1) {
  			perror("open() failed");
  			exit(1);
  		}
  	}
  	memset(buf, 0, sizeof(buf));
  	lseek(fd, 0, SEEK_SET);
  	ret = read(fd, buf, sizeof(buf));
  	if (ret == -1) {
  		perror("read() failed");
  		exit(1);
  	}
  	sscanf(buf, "%lx", &val);
  	close(fd);
  	return val;
  }
  
  void set_default_dscr(unsigned long val)
  {
  	int fd = -1, ret;
  	char buf[16];
  
  	if (fd == -1) {
  		fd = open(DSCR_DEFAULT, O_RDWR);
  		if (fd == -1) {
  			perror("open() failed");
  			exit(1);
  		}
  	}
  	sprintf(buf, "%lx\n", val);
  	ret = write(fd, buf, strlen(buf));
  	if (ret == -1) {
  		perror("write() failed");
  		exit(1);
  	}
  	close(fd);
  }
  
  double uniform_deviate(int seed)
  {
  	return seed * (1.0 / (RAND_MAX + 1.0));
  }
  #endif	/* _SELFTESTS_POWERPC_DSCR_DSCR_H */
  