clear wakeup enable bit upon resuming from suspend
The FVP specific code that gets called after a cpu has been physically
powered on after having been turned off or suspended earlier does not
clear the PWRC.PWKUPR.WEN bit. Not doing so causes problems if: a cpu
is suspended, woken from suspend, powered down through a cpu_off call
& receives a spurious interrupt. Since the WEN bit is not cleared
after the cpu woke up from suspend, the spurious wakeup will power the
cpu on. Since the cpu_off call clears the jump address in the mailbox
this spurious wakeup will cause the cpu to crash.
This patch fixes this issue by clearing the WEN bit whenever a cpu is
powered up.
Change-Id: Ic91f5dffe1ed01d76bc7fc807acf0ecd3e38ce5b
diff --git a/docs/change-log.md b/docs/change-log.md
index 841def9..3ae5fab 100644
--- a/docs/change-log.md
+++ b/docs/change-log.md
@@ -45,6 +45,9 @@
instructions for how to contribute and update copyright text in all files to
acknowledge contributors.
+* The wake up enable bit in the FVP power controller is cleared when a cpu is
+ physically powered up to prevent a spurious wake up from a subsequent cpu
+ off state.
ARM Trusted Firmware - version 0.2
==================================