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 */
128