zephyr: shim: reimplement hooks using iterables

Reimplement the hooks shim code using Zephyr iterable sections. Keep the
existing hook_registry based structure, gets rid of the per-hook init
functions and instead initializes all the list nodes from a single init
call.

BRANCH=none
BUG=b:195521227
TEST=build and run on volteer

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
Change-Id: Ic166d214ee1dcd1431ec484e5014cb297f7fb8c2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3069399
Reviewed-by: Keith Short <keithshort@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Keith Short <keithshort@chromium.org>

4 files changed, 26 insertions, 36 deletions

diff --git a/zephyr/linker/CMakeLists.txt b/zephyr/linker/CMakeLists.txt
index 316dcc71be..71955c6d9d 100644
--- a/zephyr/linker/CMakeLists.txt
+++ b/zephyr/linker/CMakeLists.txt
@@ -15,4 +15,5 @@ zephyr_linker_sources(RAM_SECTIONS image_size.ld)
 zephyr_linker_sources_ifdef(CONFIG_SOC_FAMILY_NPCX ROM_START SORT_KEY 1
   npcx-lfw.ld)
 
+zephyr_linker_sources(DATA_SECTIONS iterables-ram.ld)
 zephyr_linker_sources(SECTIONS iterables-rom.ld)
diff --git a/zephyr/linker/iterables-ram.ld b/zephyr/linker/iterables-ram.ld
new file mode 100644
index 0000000000..58318a0e78
--- /dev/null
+++ b/zephyr/linker/iterables-ram.ld
@@ -0,0 +1,3 @@
+#ifdef CONFIG_PLATFORM_EC_HOOKS
+ITERABLE_SECTION_RAM(zephyr_shim_hook_list, 4)
+#endif
diff --git a/zephyr/shim/include/zephyr_hooks_shim.h b/zephyr/shim/include/zephyr_hooks_shim.h
index 6edfdfe0a9..7175b5a6af 100644
--- a/zephyr/shim/include/zephyr_hooks_shim.h
+++ b/zephyr/shim/include/zephyr_hooks_shim.h
@@ -53,33 +53,17 @@ int hook_call_deferred(const struct deferred_data *data, int us);
 struct zephyr_shim_hook_list {
 	void (*routine)(void);
 	int priority;
+	enum hook_type type;
 	struct zephyr_shim_hook_list *next;
 };
 
 /**
- * Runtime helper for DECLARE_HOOK setup data.
- *
- * @param type		The type of hook.
- * @param routine	The handler for the hook.
- * @param priority	The priority (smaller values are executed first).
- * @param entry		A statically allocated list entry.
- */
-void zephyr_shim_setup_hook(enum hook_type type, void (*routine)(void),
-			    int priority, struct zephyr_shim_hook_list *entry);
-
-/**
  * See include/hooks.h for documentation.
  */
-#define DECLARE_HOOK(hooktype, routine, priority) \
-	_DECLARE_HOOK_1(hooktype, routine, priority, __LINE__)
-#define _DECLARE_HOOK_1(hooktype, routine, priority, line) \
-	_DECLARE_HOOK_2(hooktype, routine, priority, line)
-#define _DECLARE_HOOK_2(hooktype, routine, priority, line)                 \
-	static int _setup_hook_##line(const struct device *unused)         \
-	{                                                                  \
-		ARG_UNUSED(unused);                                        \
-		static struct zephyr_shim_hook_list lst;                   \
-		zephyr_shim_setup_hook(hooktype, routine, priority, &lst); \
-		return 0;                                                  \
-	}                                                                  \
-	SYS_INIT(_setup_hook_##line, APPLICATION, 1)
+#define DECLARE_HOOK(_hooktype, _routine, _priority)             \
+	STRUCT_SECTION_ITERABLE(zephyr_shim_hook_list,           \
+			_cros_hook_##_hooktype##_##_routine) = { \
+		.type = _hooktype,                               \
+		.routine = _routine,                             \
+		.priority = _priority,                           \
+	}
diff --git a/zephyr/shim/src/hooks.c b/zephyr/shim/src/hooks.c
index 9d196d40ef..2ec19304d3 100644
--- a/zephyr/shim/src/hooks.c
+++ b/zephyr/shim/src/hooks.c
@@ -52,24 +52,26 @@ int hook_call_deferred(const struct deferred_data *data, int us)
 
 static struct zephyr_shim_hook_list *hook_registry[HOOK_TYPE_COUNT];
 
-void zephyr_shim_setup_hook(enum hook_type type, void (*routine)(void),
-			    int priority, struct zephyr_shim_hook_list *entry)
+static int zephyr_shim_setup_hooks(const struct device *unused)
 {
-	struct zephyr_shim_hook_list **loc = &hook_registry[type];
+	STRUCT_SECTION_FOREACH(zephyr_shim_hook_list, entry) {
+		struct zephyr_shim_hook_list **loc = &hook_registry[entry->type];
 
-	/* Find the correct place to put the entry in the registry. */
-	while (*loc && (*loc)->priority < priority)
-		loc = &((*loc)->next);
+		/* Find the correct place to put the entry in the registry. */
+		while (*loc && (*loc)->priority < entry->priority)
+			loc = &((*loc)->next);
 
-	/* Setup the entry. */
-	entry->routine = routine;
-	entry->priority = priority;
-	entry->next = *loc;
+		entry->next = *loc;
 
-	/* Insert the entry. */
-	*loc = entry;
+		/* Insert the entry. */
+		*loc = entry;
+	}
+
+	return 0;
 }
 
+SYS_INIT(zephyr_shim_setup_hooks, APPLICATION, 1);
+
 void hook_notify(enum hook_type type)
 {
 	struct zephyr_shim_hook_list *p;