zephyr: test: Make get_panic_data_write mockable

The version of get_panic_data_write() that currently gets compiled in is
controlled by an `#ifdef CONFIG_BOARD_NATIVE_POSIX` block, which means
that the actual implementation used in device builds (over 30 SLOCs) is
unreachable in testing, in favor of a stub that directly returns the
pdata_ptr pointer.

This CL removes the stub native posix version of the function and makes the
real version test_mockable. Then, all test binaries that were relying on
the removed stub definition are supplied with a mocked version of
get_panic_data_write() that behaves the same way the stub did by
returning pdata_ptr directly. This frees a new test binary to test the
actual implementation.

BRANCH=None
BUG=None
TEST=./twister

Signed-off-by: Tristan Honscheid <honscheid@google.com>

Change-Id: I8228acb0147b3b3843d302c272d8715d925fddd5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4052121
Commit-Queue: Aaron Massey <aaronmassey@google.com>
Reviewed-by: Aaron Massey <aaronmassey@google.com>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>
Tested-by: Tristan Honscheid <honscheid@google.com>
Auto-Submit: Tristan Honscheid <honscheid@google.com>

6 files changed, 47 insertions, 6 deletions

diff --git a/common/panic_output.c b/common/panic_output.c
index 55d551f548..fd163b21f5 100644
--- a/common/panic_output.c
+++ b/common/panic_output.c
@@ -196,13 +196,13 @@ static uint32_t get_panic_data_size(void)
  * should be used when we are sure that we don't need it.
  */
 #ifdef CONFIG_BOARD_NATIVE_POSIX
-struct panic_data *get_panic_data_write(void)
+struct panic_data *test_get_panic_data_pointer(void)
 {
 	return pdata_ptr;
 }
-#else
-/* LCOV_EXCL_START - Can't cover non posix lines (yet) */
-struct panic_data *get_panic_data_write(void)
+#endif
+
+test_mockable struct panic_data *get_panic_data_write(void)
 {
 	/*
 	 * Pointer to panic_data structure. It may not point to
@@ -295,8 +295,6 @@ struct panic_data *get_panic_data_write(void)
 
 	return pdata_ptr;
 }
-/* LCOV_EXCL_STOP */
-#endif /* CONFIG_BOARD_NATIVE_POSIX */
 
 static void panic_init(void)
 {
diff --git a/include/panic.h b/include/panic.h
index 25829017ea..efd3e4d86b 100644
--- a/include/panic.h
+++ b/include/panic.h
@@ -292,6 +292,15 @@ struct panic_data *panic_get_data(void);
  */
 uintptr_t get_panic_data_start(void);
 
+#ifdef CONFIG_BOARD_NATIVE_POSIX
+/**
+ * @brief Test-only function for accessing the pdata_ptr object.
+ *
+ * @return struct panic_data* pdata_ptr
+ */
+struct panic_data *test_get_panic_data_pointer(void);
+#endif
+
 /*
  * Return a pointer to panic_data structure that can be safely written.
  * Please note that this function can move jump data and jump tags.
diff --git a/zephyr/test/drivers/default/CMakeLists.txt b/zephyr/test/drivers/default/CMakeLists.txt
index 07688db4f2..08d5caa04b 100644
--- a/zephyr/test/drivers/default/CMakeLists.txt
+++ b/zephyr/test/drivers/default/CMakeLists.txt
@@ -97,6 +97,11 @@ target_sources(app PRIVATE
     src/watchdog.c
 )
 
+add_subdirectory(
+    ${PLATFORM_EC}/zephyr/test/drivers/mock_panic_output
+    mock_panic_output
+)
+
 # This test does not work when power functions are mocked, so only run it for
 # the plain `drivers.default` test case.
 zephyr_library_sources_ifndef(CONFIG_POWER_SEQUENCE_MOCK src/chipset.c)
diff --git a/zephyr/test/drivers/host_cmd/CMakeLists.txt b/zephyr/test/drivers/host_cmd/CMakeLists.txt
index 14733253c3..6e6cf0f48a 100644
--- a/zephyr/test/drivers/host_cmd/CMakeLists.txt
+++ b/zephyr/test/drivers/host_cmd/CMakeLists.txt
@@ -25,3 +25,8 @@ target_sources(app PRIVATE
     src/usb_pd_control.c
     src/usb_pd_host_cmd.c
 )
+
+add_subdirectory(
+    ${PLATFORM_EC}/zephyr/test/drivers/mock_panic_output
+    mock_panic_output
+)
diff --git a/zephyr/test/drivers/mock_panic_output/CMakeLists.txt b/zephyr/test/drivers/mock_panic_output/CMakeLists.txt
new file mode 100644
index 0000000000..2e3b959805
--- /dev/null
+++ b/zephyr/test/drivers/mock_panic_output/CMakeLists.txt
@@ -0,0 +1,6 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Add source files
+target_sources(app PRIVATE src/test_get_panic_data_write.c)
diff --git a/zephyr/test/drivers/mock_panic_output/src/test_get_panic_data_write.c b/zephyr/test/drivers/mock_panic_output/src/test_get_panic_data_write.c
new file mode 100644
index 0000000000..5d7bcf9010
--- /dev/null
+++ b/zephyr/test/drivers/mock_panic_output/src/test_get_panic_data_write.c
@@ -0,0 +1,18 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "panic.h"
+
+/**
+ * @brief Override for testing. This method simply returns `pdata_ptr` and
+ *        bypasses the usual logic in `common/panic_output.c`
+ *
+ * @return struct panic_data* Pointer to the pdata_ptr object
+ */
+struct panic_data *get_panic_data_write(void)
+{
+	/* Test-only helper method to access `pdata_ptr` in `panic_output.c` */
+	return test_get_panic_data_pointer();
+}