1 /*
2  * POWER Data Stream Control Register (DSCR) sysfs interface test
3  *
4  * This test updates to system wide DSCR default through the sysfs interface
5  * and then verifies that all the CPU specific DSCR defaults are updated as
6  * well verified from their sysfs interfaces.
7  *
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 #include "dscr.h"
15 
16 static int check_cpu_dscr_default(char *file, unsigned long val)
17 {
18 	char buf[10];
19 	int fd, rc;
20 
21 	fd = open(file, O_RDWR);
22 	if (fd == -1) {
23 		perror("open() failed");
24 		return 1;
25 	}
26 
27 	rc = read(fd, buf, sizeof(buf));
28 	if (rc == -1) {
29 		perror("read() failed");
30 		return 1;
31 	}
32 	close(fd);
33 
34 	buf[rc] = '\0';
35 	if (strtol(buf, NULL, 16) != val) {
36 		printf("DSCR match failed: %ld (system) %ld (cpu)\n",
37 					val, strtol(buf, NULL, 16));
38 		return 1;
39 	}
40 	return 0;
41 }
42 
43 static int check_all_cpu_dscr_defaults(unsigned long val)
44 {
45 	DIR *sysfs;
46 	struct dirent *dp;
47 	char file[LEN_MAX];
48 
49 	sysfs = opendir(CPU_PATH);
50 	if (!sysfs) {
51 		perror("opendir() failed");
52 		return 1;
53 	}
54 
55 	while ((dp = readdir(sysfs))) {
56 		int len;
57 
58 		if (!(dp->d_type & DT_DIR))
59 			continue;
60 		if (!strcmp(dp->d_name, "cpuidle"))
61 			continue;
62 		if (!strstr(dp->d_name, "cpu"))
63 			continue;
64 
65 		len = snprintf(file, LEN_MAX, "%s%s/dscr", CPU_PATH, dp->d_name);
66 		if (len >= LEN_MAX)
67 			continue;
68 		if (access(file, F_OK))
69 			continue;
70 
71 		if (check_cpu_dscr_default(file, val))
72 			return 1;
73 	}
74 	closedir(sysfs);
75 	return 0;
76 }
77 
78 int dscr_sysfs(void)
79 {
80 	unsigned long orig_dscr_default;
81 	int i, j;
82 
83 	orig_dscr_default = get_default_dscr();
84 	for (i = 0; i < COUNT; i++) {
85 		for (j = 0; j < DSCR_MAX; j++) {
86 			set_default_dscr(j);
87 			if (check_all_cpu_dscr_defaults(j))
88 				goto fail;
89 		}
90 	}
91 	set_default_dscr(orig_dscr_default);
92 	return 0;
93 fail:
94 	set_default_dscr(orig_dscr_default);
95 	return 1;
96 }
97 
98 int main(int argc, char *argv[])
99 {
100 	return test_harness(dscr_sysfs, "dscr_sysfs_test");
101 }
102