linux/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcra_thresh_cmp_test.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2022, Kajol Jain, IBM Corp.
 */

#include <stdio.h>
#include <stdlib.h>

#include "../event.h"
#include "misc.h"
#include "utils.h"

/*
 * Primary PMU event used here is PM_MRK_INST_CMPL (0x401e0)
 * Threshold event selection used is issue to complete for cycles
 * Sampling criteria is Load only sampling
 */
#define p9_EventCode 0x13E35340401e0
#define p10_EventCode 0x35340401e0

extern void thirty_two_instruction_loop_with_ll_sc(u64 loops, u64 *ll_sc_target);

/* A perf sampling test to test mmcra fields */
static int mmcra_thresh_cmp(void)
{
	struct event event;
	u64 *intr_regs;
	u64 dummy;

	/* Check for platform support for the test */
	SKIP_IF(check_pvr_for_sampling_tests());

	/* Skip for comapt mode */
	SKIP_IF(check_for_compat_mode());

	/* Init the event for the sampling test */
	if (!have_hwcap2(PPC_FEATURE2_ARCH_3_1)) {
		event_init_sampling(&event, p9_EventCode);
	} else {
		event_init_sampling(&event, p10_EventCode);
		event.attr.config1 = 1000;
	}

	event.attr.sample_regs_intr = platform_extended_mask;
	FAIL_IF(event_open(&event));
	event.mmap_buffer = event_sample_buf_mmap(event.fd, 1);

	FAIL_IF(event_enable(&event));

	/* workload to make the event overflow */
	thirty_two_instruction_loop_with_ll_sc(1000000, &dummy);

	FAIL_IF(event_disable(&event));

	/* Check for sample count */
	FAIL_IF(!collect_samples(event.mmap_buffer));

	intr_regs = get_intr_regs(&event, event.mmap_buffer);

	/* Check for intr_regs */
	FAIL_IF(!intr_regs);

	/* Verify that thresh cmp match with the corresponding event code fields */
	FAIL_IF(get_thresh_cmp_val(event) !=
			get_mmcra_thd_cmp(get_reg_value(intr_regs, "MMCRA"), 4));

	event_close(&event);
	return 0;
}

int main(void)
{
	FAIL_IF(test_harness(mmcra_thresh_cmp, "mmcra_thresh_cmp"));
}