[PATCH 15/20] selftest/powerpc/pmu/: Add interface test for mmcr1_comb field

[Kajol Jain <kjain@linux.ibm.com>]

From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>

The testcase uses event code "0x26880" to verify
the settings for different fields in Monitor Mode Control
Register 1 (MMCR1). The field include PMCxCOMB.
Checks if this field are translated correctly via perf
interface to MMCR1

Add selftest for mmcr1 comb field.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
---
 .../powerpc/pmu/sampling_tests/Makefile       |  6 +-
 .../pmu/sampling_tests/mmcr1_comb_test.c      | 66 +++++++++++++++++++
 2 files changed, 70 insertions(+), 2 deletions(-)
 create mode 100644 tools/testing/selftests/powerpc/pmu/sampling_tests/mmcr1_comb_test.c

diff --git a/tools/testing/selftests/powerpc/pmu/sampling_tests/Makefile b/tools/testing/selftests/powerpc/pmu/sampling_tests/Makefile
index d27d5084a3ce..bb5ffd2e322d 100644
--- a/tools/testing/selftests/powerpc/pmu/sampling_tests/Makefile
+++ b/tools/testing/selftests/powerpc/pmu/sampling_tests/Makefile
@@ -2,7 +2,8 @@
 include ../../../../../../scripts/Kbuild.include
 
 all: $(TEST_GEN_PROGS) mmcr0_exceptionbits_test.c mmcr0_cc56run_test.c mmcr0_pmccext_test.c \
-			mmcr0_pmcjce_test.c mmcr0_fc56_pmc1ce_test.c mmcr0_fc56_pmc56_test.c
+			mmcr0_pmcjce_test.c mmcr0_fc56_pmc1ce_test.c mmcr0_fc56_pmc56_test.c \
+			mmcr1_comb_test.c
 
 noarg:
 	$(MAKE) -C ../../
@@ -14,7 +15,8 @@ no-pie-option := $(call try-run, echo 'int main() { return 0; }' | \
 	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -no-pie -x c - -o "$$TMP", -no-pie)
 
 TEST_GEN_PROGS := mmcr0_exceptionbits_test mmcr0_cc56run_test mmcr0_pmccext_test \
-		   mmcr0_pmcjce_test mmcr0_fc56_pmc1ce_test mmcr0_fc56_pmc56_test
+		   mmcr0_pmcjce_test mmcr0_fc56_pmc1ce_test mmcr0_fc56_pmc56_test \
+		   mmcr1_comb_test
 
 LDFLAGS += $(no-pie-option)
 
diff --git a/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcr1_comb_test.c b/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcr1_comb_test.c
new file mode 100644
index 000000000000..0f183c2f074d
--- /dev/null
+++ b/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcr1_comb_test.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2022, Athira Rajeev, IBM Corp.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "../event.h"
+#include "misc.h"
+#include "utils.h"
+
+/* All successful D-side store dispatches for this thread that were L2 Miss */
+#define EventCode 0x46880
+
+extern void thirty_two_instruction_loop_with_ll_sc(u64 loops, u64 *ll_sc_target);
+
+/*
+ * A perf sampling test for mmcr1
+ * fields : comb.
+ */
+static int mmcr1_comb(void)
+{
+	struct event event;
+	u64 *intr_regs;
+	u64 dummy;
+
+	/* Check for platform support for the test */
+	SKIP_IF(check_pvr_for_sampling_tests());
+
+	/* Init the event for the sampling test */
+	event_init_sampling(&event, EventCode);
+	event.attr.sample_regs_intr = platform_extended_mask;
+	FAIL_IF(event_open(&event));
+	event.mmap_buffer = event_sample_buf_mmap(event.fd, 1);
+
+	event_enable(&event);
+
+	/* workload to make the event overflow */
+	thirty_two_instruction_loop_with_ll_sc(10000000, &dummy);
+
+	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 comb field match with
+	 * corresponding event code fields
+	 */
+	FAIL_IF(EV_CODE_EXTRACT(event.attr.config, comb) != GET_MMCR_FIELD(1,
+				get_reg_value(intr_regs, "MMCR1"), 4, comb));
+
+	event_close(&event);
+	return 0;
+}
+
+int main(void)
+{
+	FAIL_IF(test_harness(mmcr1_comb, "mmcr1_comb"));
+}
-- 
2.27.0