test: shim system.c system_hibernate()

Add test that verifies the system_hibernate() function calls the
chip-specific cros system routine for hibernation and can respond to an
error from the aforementioned test without going into an infinite loop.

BRANCH=none
BUG=b:236074898
TEST=twister --clobber -i -s zephyr/test/system_shim/system_shim.default

Signed-off-by: Aaron Massey <aaronmassey@google.com>
Change-Id: Ice3aed18d7f9f858263aac4aecc980ca6720bfe1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3936482
Reviewed-by: Keith Short <keithshort@chromium.org>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>

2 files changed, 72 insertions, 1 deletions

diff --git a/zephyr/shim/src/system.c b/zephyr/shim/src/system.c
index c2182e92c5..b3dd2c121b 100644
--- a/zephyr/shim/src/system.c
+++ b/zephyr/shim/src/system.c
@@ -159,9 +159,15 @@ test_mockable void system_hibernate(uint32_t seconds, uint32_t microseconds)
 		return;
 	}
 
+	/*
+	 * Ignore infinite loop for coverage as the test would fail via timeout
+	 * and not report regardless of executing code.
+	 */
+	/* LCOV_EXCL_START */
 	/* should never reach this point */
 	while (1)
 		continue;
+	/* LCOV_EXCL_STOP */
 }
 
 #ifdef CONFIG_PM
diff --git a/zephyr/test/system_shim/test_system.c b/zephyr/test/system_shim/test_system.c
index ddf992169a..e4b4ddebc6 100644
--- a/zephyr/test/system_shim/test_system.c
+++ b/zephyr/test/system_shim/test_system.c
@@ -3,6 +3,7 @@
  * found in the LICENSE file.
  */
 
+#include <setjmp.h>
 #include <zephyr/device.h>
 #include <zephyr/drivers/bbram.h>
 #include <zephyr/fff.h>
@@ -24,11 +25,14 @@ static char mock_data[64] =
 	"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@";
 
 FAKE_VALUE_FUNC(uint64_t, cros_system_native_posix_deep_sleep_ticks,
-		const struct device *)
+		const struct device *);
+FAKE_VALUE_FUNC(int, cros_system_native_posix_hibernate, const struct device *,
+		uint32_t, uint32_t);
 
 static void system_before_after(void *test_data)
 {
 	RESET_FAKE(cros_system_native_posix_deep_sleep_ticks);
+	RESET_FAKE(cros_system_native_posix_hibernate);
 }
 
 ZTEST_SUITE(system, NULL, NULL, system_before_after, system_before_after, NULL);
@@ -85,6 +89,67 @@ ZTEST(system, test_system_set_get_scratchpad)
 	zassert_equal(scratch_read, scratch_set);
 }
 
+static jmp_buf jmp_hibernate;
+
+static int _test_cros_system_native_posix_hibernate(const struct device *dev,
+						    uint32_t seconds,
+						    uint32_t microseconds)
+{
+	longjmp(jmp_hibernate, 1);
+
+	return 0;
+}
+
+ZTEST(system, test_system_hibernate)
+{
+	/*
+	 * Due to setjmp usage, this test provides no coverage, but does
+	 * actually cover the code. This is due to a bug in LCOV.
+	 */
+	const struct device *sys_dev = device_get_binding("CROS_SYSTEM");
+	int ret = setjmp(jmp_hibernate);
+	/* Validate 0th and last bit preserved*/
+	uint32_t secs = BIT(31) + 1;
+	uint32_t msecs = BIT(31) + 3;
+
+	zassert_not_null(sys_dev);
+
+	cros_system_native_posix_hibernate_fake.custom_fake =
+		_test_cros_system_native_posix_hibernate;
+
+	if (ret == 0) {
+		system_hibernate(secs, msecs);
+	}
+
+	zassert_not_equal(ret, 0);
+
+	zassert_equal(cros_system_native_posix_hibernate_fake.call_count, 1);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg0_val,
+		      sys_dev);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg1_val, secs);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg2_val, msecs);
+}
+
+ZTEST(system, test_system_hibernate__failure)
+{
+	const struct device *sys_dev = device_get_binding("CROS_SYSTEM");
+	/* Validate 0th and last bit preserved*/
+	uint32_t secs = BIT(31) + 1;
+	uint32_t msecs = BIT(31) + 3;
+
+	zassert_not_null(sys_dev);
+
+	cros_system_native_posix_hibernate_fake.return_val = -1;
+
+	system_hibernate(secs, msecs);
+
+	zassert_equal(cros_system_native_posix_hibernate_fake.call_count, 1);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg0_val,
+		      sys_dev);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg1_val, secs);
+	zassert_equal(cros_system_native_posix_hibernate_fake.arg2_val, msecs);
+}
+
 ZTEST_USER(system, test_system_console_cmd__idlestats)
 {
 	const struct device *sys_dev = device_get_binding("CROS_SYSTEM");