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 ACCESS_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 */
126