1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * POWER Data Stream Control Register (DSCR) explicit test
 4 *
 5 * This test modifies the DSCR value using mtspr instruction and
 6 * verifies the change with mfspr instruction. It uses both the
 7 * privilege state SPR and the problem state SPR for this purpose.
 8 *
 9 * When using the privilege state SPR, the instructions such as
10 * mfspr or mtspr are priviledged and the kernel emulates them
11 * for us. Instructions using problem state SPR can be exuecuted
12 * directly without any emulation if the HW supports them. Else
13 * they also get emulated by the kernel.
14 *
15 * Copyright 2012, Anton Blanchard, IBM Corporation.
16 * Copyright 2015, Anshuman Khandual, IBM Corporation.
17 */
18#include "dscr.h"
19
20int dscr_explicit(void)
21{
22	unsigned long i, dscr = 0;
23
 
 
24	srand(getpid());
25	set_dscr(dscr);
26
27	for (i = 0; i < COUNT; i++) {
28		unsigned long cur_dscr, cur_dscr_usr;
29		double ret = uniform_deviate(rand());
30
31		if (ret < 0.001) {
32			dscr++;
33			if (dscr > DSCR_MAX)
34				dscr = 0;
35
36			set_dscr(dscr);
37		}
38
39		cur_dscr = get_dscr();
40		if (cur_dscr != dscr) {
41			fprintf(stderr, "Kernel DSCR should be %ld but "
42					"is %ld\n", dscr, cur_dscr);
43			return 1;
44		}
45
46		ret = uniform_deviate(rand());
47		if (ret < 0.001) {
48			dscr++;
49			if (dscr > DSCR_MAX)
50				dscr = 0;
51
52			set_dscr_usr(dscr);
53		}
54
55		cur_dscr_usr = get_dscr_usr();
56		if (cur_dscr_usr != dscr) {
57			fprintf(stderr, "User DSCR should be %ld but "
58					"is %ld\n", dscr, cur_dscr_usr);
59			return 1;
60		}
61	}
62	return 0;
63}
64
65int main(int argc, char *argv[])
66{
67	return test_harness(dscr_explicit, "dscr_explicit_test");
68}

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * POWER Data Stream Control Register (DSCR) explicit test
 4 *
 5 * This test modifies the DSCR value using mtspr instruction and
 6 * verifies the change with mfspr instruction. It uses both the
 7 * privilege state SPR and the problem state SPR for this purpose.
 8 *
 9 * When using the privilege state SPR, the instructions such as
10 * mfspr or mtspr are priviledged and the kernel emulates them
11 * for us. Instructions using problem state SPR can be exuecuted
12 * directly without any emulation if the HW supports them. Else
13 * they also get emulated by the kernel.
14 *
15 * Copyright 2012, Anton Blanchard, IBM Corporation.
16 * Copyright 2015, Anshuman Khandual, IBM Corporation.
17 */
18#include "dscr.h"
19
20int dscr_explicit(void)
21{
22	unsigned long i, dscr = 0;
23
24	SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
25
26	srand(getpid());
27	set_dscr(dscr);
28
29	for (i = 0; i < COUNT; i++) {
30		unsigned long cur_dscr, cur_dscr_usr;
31		double ret = uniform_deviate(rand());
32
33		if (ret < 0.001) {
34			dscr++;
35			if (dscr > DSCR_MAX)
36				dscr = 0;
37
38			set_dscr(dscr);
39		}
40
41		cur_dscr = get_dscr();
42		if (cur_dscr != dscr) {
43			fprintf(stderr, "Kernel DSCR should be %ld but "
44					"is %ld\n", dscr, cur_dscr);
45			return 1;
46		}
47
48		ret = uniform_deviate(rand());
49		if (ret < 0.001) {
50			dscr++;
51			if (dscr > DSCR_MAX)
52				dscr = 0;
53
54			set_dscr_usr(dscr);
55		}
56
57		cur_dscr_usr = get_dscr_usr();
58		if (cur_dscr_usr != dscr) {
59			fprintf(stderr, "User DSCR should be %ld but "
60					"is %ld\n", dscr, cur_dscr_usr);
61			return 1;
62		}
63	}
64	return 0;
65}
66
67int main(int argc, char *argv[])
68{
69	return test_harness(dscr_explicit, "dscr_explicit_test");
70}