Add tick task

Adds a new HOOK_TICK event which is called every 250ms (LM4) or 500ms
(STM32).  This will be used to consolidate a number of tasks which do
small amounts of work infrequently, and previously needed their own
task functions.

This CL adds the tick task; subsequent CLs will consolidate watchdog
and other tasks into tick hooks.

BUG=chrome-os-partner:15714
BRANCH=none
TEST=taskinfo shows TICK task as lowest priority

Change-Id: I9068ee99d56a5bf5c12afd86ad51998c013f4954
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/36908
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/common/hooks.c b/common/hooks.c
index 81d84b3d00..385f0e0478 100644
--- a/common/hooks.c
+++ b/common/hooks.c
@@ -7,6 +7,7 @@
 
 #include "hooks.h"
 #include "link_defs.h"
+#include "timer.h"
 #include "util.h"
 
 struct hook_ptrs {
@@ -29,6 +30,7 @@ static const struct hook_ptrs hook_list[] = {
 	{__hooks_chipset_shutdown, __hooks_chipset_shutdown_end},
 	{__hooks_ac_change, __hooks_ac_change_end},
 	{__hooks_lid_change, __hooks_lid_change_end},
+	{__hooks_tick, __hooks_tick_end},
 };
 
 void hook_notify(enum hook_type type)
@@ -59,3 +61,17 @@ void hook_notify(enum hook_type type)
 		}
 	}
 }
+
+void hook_task(void)
+{
+	while (1) {
+		uint64_t t = get_time().val;
+
+		hook_notify(HOOK_TICK);
+
+		/* Use up the rest of our hook tick interval */
+		t = get_time().val - t;
+		if (t < HOOK_TICK_INTERVAL)
+			usleep(HOOK_TICK_INTERVAL - t);
+	}
+}