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1 /*
2  * Copyright 2014, Michael Ellerman, IBM Corp.
3  * Licensed under GPLv2.
4  */
5 
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <stdbool.h>
9 
10 #include "ebb.h"
11 
12 
13 /*
14  * Test of counting cycles while manipulating the user accessible bits in MMCR2.
15  */
16 
17 /* We use two values because the first freezes PMC1 and so we would get no EBBs */
18 #define MMCR2_EXPECTED_1 0x4020100804020000UL /* (FC1P|FC2P|FC3P|FC4P|FC5P|FC6P) */
19 #define MMCR2_EXPECTED_2 0x0020100804020000UL /* (     FC2P|FC3P|FC4P|FC5P|FC6P) */
20 
21 
cycles_with_mmcr2(void)22 int cycles_with_mmcr2(void)
23 {
24 	struct event event;
25 	uint64_t val, expected[2], actual;
26 	int i;
27 	bool bad_mmcr2;
28 
29 	SKIP_IF(!ebb_is_supported());
30 
31 	event_init_named(&event, 0x1001e, "cycles");
32 	event_leader_ebb_init(&event);
33 
34 	event.attr.exclude_kernel = 1;
35 	event.attr.exclude_hv = 1;
36 	event.attr.exclude_idle = 1;
37 
38 	FAIL_IF(event_open(&event));
39 
40 	ebb_enable_pmc_counting(1);
41 	setup_ebb_handler(standard_ebb_callee);
42 	ebb_global_enable();
43 
44 	FAIL_IF(ebb_event_enable(&event));
45 
46 	mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
47 
48 	/* XXX Set of MMCR2 must be after enable */
49 	expected[0] = MMCR2_EXPECTED_1;
50 	expected[1] = MMCR2_EXPECTED_2;
51 	i = 0;
52 	bad_mmcr2 = false;
53 
54 	/* Make sure we loop until we take at least one EBB */
55 	while ((ebb_state.stats.ebb_count < 20 && !bad_mmcr2) ||
56 		ebb_state.stats.ebb_count < 1)
57 	{
58 		mtspr(SPRN_MMCR2, expected[i % 2]);
59 
60 		FAIL_IF(core_busy_loop());
61 
62 		val = mfspr(SPRN_MMCR2);
63 		if (val != expected[i % 2]) {
64 			bad_mmcr2 = true;
65 			actual = val;
66 		}
67 
68 		i++;
69 	}
70 
71 	ebb_global_disable();
72 	ebb_freeze_pmcs();
73 
74 	count_pmc(1, sample_period);
75 
76 	dump_ebb_state();
77 
78 	event_close(&event);
79 
80 	FAIL_IF(ebb_state.stats.ebb_count == 0);
81 
82 	if (bad_mmcr2)
83 		printf("Bad MMCR2 value seen is 0x%lx\n", actual);
84 
85 	FAIL_IF(bad_mmcr2);
86 
87 	return 0;
88 }
89 
main(void)90 int main(void)
91 {
92 	return test_harness(cycles_with_mmcr2, "cycles_with_mmcr2");
93 }
94