1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * POWER Data Stream Control Register (DSCR) sysfs interface test
4 *
5 * This test updates to system wide DSCR default through the sysfs interface
6 * and then verifies that all the CPU specific DSCR defaults are updated as
7 * well verified from their sysfs interfaces.
8 *
9 * Copyright 2015, Anshuman Khandual, IBM Corporation.
10 */
11 #include "dscr.h"
12
check_cpu_dscr_default(char * file,unsigned long val)13 static int check_cpu_dscr_default(char *file, unsigned long val)
14 {
15 unsigned long cpu_dscr;
16 int err;
17
18 err = read_ulong(file, &cpu_dscr, 16);
19 if (err)
20 return err;
21
22 if (cpu_dscr != val) {
23 printf("DSCR match failed: %ld (system) %ld (cpu)\n",
24 val, cpu_dscr);
25 return 1;
26 }
27 return 0;
28 }
29
check_all_cpu_dscr_defaults(unsigned long val)30 static int check_all_cpu_dscr_defaults(unsigned long val)
31 {
32 DIR *sysfs;
33 struct dirent *dp;
34 char file[LEN_MAX];
35
36 sysfs = opendir(CPU_PATH);
37 if (!sysfs) {
38 perror("opendir() failed");
39 return 1;
40 }
41
42 while ((dp = readdir(sysfs))) {
43 int len;
44
45 if (!(dp->d_type & DT_DIR))
46 continue;
47 if (!strcmp(dp->d_name, "cpuidle"))
48 continue;
49 if (!strstr(dp->d_name, "cpu"))
50 continue;
51
52 len = snprintf(file, LEN_MAX, "%s%s/dscr", CPU_PATH, dp->d_name);
53 if (len >= LEN_MAX)
54 continue;
55 if (access(file, F_OK))
56 continue;
57
58 if (check_cpu_dscr_default(file, val)) {
59 closedir(sysfs);
60 return 1;
61 }
62 }
63 closedir(sysfs);
64 return 0;
65 }
66
dscr_sysfs(void)67 int dscr_sysfs(void)
68 {
69 unsigned long orig_dscr_default;
70 int i, j;
71
72 SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
73
74 orig_dscr_default = get_default_dscr();
75 for (i = 0; i < COUNT; i++) {
76 for (j = 0; j < DSCR_MAX; j++) {
77 set_default_dscr(j);
78 if (check_all_cpu_dscr_defaults(j))
79 goto fail;
80 }
81 }
82 set_default_dscr(orig_dscr_default);
83 return 0;
84 fail:
85 set_default_dscr(orig_dscr_default);
86 return 1;
87 }
88
main(int argc,char * argv[])89 int main(int argc, char *argv[])
90 {
91 return test_harness(dscr_sysfs, "dscr_sysfs_test");
92 }
93