system: Enable/Disable low power idle in run time

We have enable_sleep()/disable_sleep() to enable/disable
EC deep sleep mode in runtime.

Here we introduce similar interfaces to enable/disable
EC idle (sleep) mode.

BUG=b:78792296
BRANCH=scarlet
TEST=Confirm idle mode is enabled/disabled when
enable_idle() and disable_idle() are called.

Change-Id: I2484f08a066523441064968da99c47de9342ecf0
Signed-off-by: Philip Chen <philipchen@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1072370
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Philip Chen <philipchen@chromium.org>
Commit-Queue: Philip Chen <philipchen@chromium.org>
Tested-by: Philip Chen <philipchen@chromium.org>
(cherry picked from commit c6b6626cdccef04b0ff203aaed0d84dbdcecf8b7)
Reviewed-on: https://chromium-review.googlesource.com/1076708
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/include/system.h b/include/system.h
index acc3f71471..9b58203c5c 100644
--- a/include/system.h
+++ b/include/system.h
@@ -479,6 +479,30 @@ static inline void disable_sleep(uint32_t mask)
 	atomic_or(&sleep_mask, mask);
 }
 
+#ifdef CONFIG_LOW_POWER_IDLE_LIMITED
+/*
+ * If this variable is nonzero, all levels of idle modes are disabled.
+ * Do NOT access it directly. Use idle_is_disabled() to read it and
+ * enable_idle()/disable_idle() to write it.
+ */
+extern uint32_t idle_disabled;
+
+static inline uint32_t idle_is_disabled(void)
+{
+	return idle_disabled;
+}
+
+static inline void disable_idle(void)
+{
+	atomic_or(&idle_disabled, 1);
+}
+
+static inline void enable_idle(void)
+{
+	atomic_clear(&idle_disabled, 1);
+}
+#endif
+
 /* The following three functions are not available on all chips. */
 /**
  * Postpone sleeping for at least this long, regardless of sleep_mask.