mmcra_bhrb_disable_test.c

 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
13extern 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 */
22static 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 ISA v3.1
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
63int main(void)
64{
65	return test_harness(mmcra_bhrb_disable_test, "mmcra_bhrb_disable_test");
66}