cpus: denver: reset power state to 'C1' on boot

Denver CPUs expect the power state field to be reset to 'C1'
during boot. This patch updates the reset handler to reset the
ACTLR_.PMSTATE field to 'C1' state during CPU boot.

Change-Id: I7cb629627a4dd1a30ec5cbb3a5e90055244fe30c
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

include/lib/cpus/aarch64/denver.h

 /*
- * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -20,6 +20,12 @@
 /* CPU state ids - implementation defined */
 #define DENVER_CPU_STATE_POWER_DOWN	U(0x3)
 
+/* Core power management states */
+#define DENVER_CPU_PMSTATE_C1		U(0x1)
+#define DENVER_CPU_PMSTATE_C6		U(0x6)
+#define DENVER_CPU_PMSTATE_C7		U(0x7)
+#define DENVER_CPU_PMSTATE_MASK		U(0xF)
+
 #ifndef __ASSEMBLY__
 
 /* Disable Dynamic Code Optimisation */

lib/cpus/aarch64/denver.S

@@ -236,6 +236,15 @@ func denver_reset_func
 	msr	vbar_el3, x0
 #endif
 
+	/* ----------------------------------------------------
+	 * Reset ACTLR.PMSTATE to C1 state
+	 * ----------------------------------------------------
+	 */
+	mrs	x0, actlr_el1
+	bic	x0, x0, #DENVER_CPU_PMSTATE_MASK
+	orr	x0, x0, #DENVER_CPU_PMSTATE_C1
+	msr	actlr_el1, x0
+
 	/* ----------------------------------------------------
 	 * Enable dynamic code optimizer (DCO)
 	 * ----------------------------------------------------