armv8/secmon: Disable and Enable GIC in PSCI path

Disable and enable GIC before switching off a CPU and after bringing
it up back respectively.

BUG=None
BRANCH=None
TEST=Compiles successfully and psci commands work for ryu.

Change-Id: Ib43af60e994e3d072e897a59595775d0b2dcef83
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: d5271d731f0a569583c2b32ef6726dadbfa846d3
Original-Change-Id: I672945fcb0ff416008a1aad5ed625cfa91bb9cbd
Original-Signed-off-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/265623
Original-Trybot-Ready: Furquan Shaikh <furquan@chromium.org>
Original-Tested-by: Furquan Shaikh <furquan@chromium.org>
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9926
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)

src/arch/arm64/armv8/secmon/psci.c

@@ -17,6 +17,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
  */
 
+#include <gic.h>
 #include <string.h>
 #include <stdlib.h>
 #include <smp/spinlock.h>
@@ -231,6 +232,7 @@ void psci_turn_on_self(const struct cpu_action *action)
 
 void psci_cpu_entry(void)
 {
+	gic_enable();
 	/*
 	 * Just wait for an action to be performed. Only CPU_ON is supported
 	 * initially. i.e. no power down then wake.
@@ -327,6 +329,8 @@ static int psci_turn_off_node(struct psci_node *e, int level,
 	if (ret != PSCI_RET_SUCCESS)
 		return ret;
 
+	gic_disable();
+
 	/* Should never return. */
 	ret = soc_psci_ops.cmd_commit(&cmd);