xref: /linux/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcra_bhrb_disable_test.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2022, Kajol Jain, IBM Corp.
4  */
5 
6 #include <stdio.h>
7 #include <stdlib.h>
8 
9 #include "../event.h"
10 #include "misc.h"
11 #include "utils.h"
12 
13 extern void thirty_two_instruction_loop(int loops);
14 
15 /* Instructions */
16 #define EventCode 0x500fa
17 
18 /*
19  * A perf sampling test for mmcra
20  * field: bhrb_disable.
21  */
mmcra_bhrb_disable_test(void)22 static int mmcra_bhrb_disable_test(void)
23 {
24 	struct event event;
25 	u64 *intr_regs;
26 
27 	/*
28 	 * Check for platform support for the test.
29 	 * This test is only aplicable on power10
30 	 */
31 	SKIP_IF(check_pvr_for_sampling_tests());
32 	SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_3_1));
33 
34 	 /* Init the event for the sampling test */
35 	event_init_sampling(&event, EventCode);
36 	event.attr.sample_regs_intr = platform_extended_mask;
37 	event.attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
38 	event.attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY;
39 	event.attr.exclude_kernel = 1;
40 
41 	FAIL_IF(event_open(&event));
42 	event.mmap_buffer = event_sample_buf_mmap(event.fd, 1);
43 
44 	FAIL_IF(event_enable(&event));
45 
46 	/* workload to make the event overflow */
47 	thirty_two_instruction_loop(10000);
48 
49 	FAIL_IF(event_disable(&event));
50 
51 	intr_regs = get_intr_regs(&event, event.mmap_buffer);
52 
53 	/* Check for intr_regs */
54 	FAIL_IF(!intr_regs);
55 
56 	/* Verify that bhrb_disable bit is set in MMCRA */
57 	FAIL_IF(get_mmcra_bhrb_disable(get_reg_value(intr_regs, "MMCRA"), 5));
58 
59 	event_close(&event);
60 	return 0;
61 }
62 
main(void)63 int main(void)
64 {
65 	return test_harness(mmcra_bhrb_disable_test, "mmcra_bhrb_disable_test");
66 }
67