Initialise CPU contexts from entry_point_info

Consolidate all BL3-1 CPU context initialization for cold boot, PSCI
and SPDs into two functions:
*  The first uses entry_point_info to initialize the relevant
   cpu_context for first entry into a lower exception level on a CPU
*  The second populates the EL1 and EL2 system registers as needed
   from the cpu_context to ensure correct entry into the lower EL

This patch alters the way that BL3-1 determines which exception level
is used when first entering EL1 or EL2 during cold boot - this is now
fully determined by the SPSR value in the entry_point_info for BL3-3,
as set up by the platform code in BL2 (or otherwise provided to BL3-1).

In the situation that EL1 (or svc mode) is selected for a processor
that supports EL2, the context management code will now configure all
essential EL2 register state to ensure correct execution of EL1. This
allows the platform code to run non-secure EL1 payloads directly
without requiring a small EL2 stub or OS loader.

Change-Id: If9fbb2417e82d2226e47568203d5a369f39d3b0f
diff --git a/include/common/bl_common.h b/include/common/bl_common.h
index 2f3bade..f5e2a9a 100644
--- a/include/common/bl_common.h
+++ b/include/common/bl_common.h
@@ -33,7 +33,6 @@
 
 #define SECURE		0x0
 #define NON_SECURE	0x1
-#define PARAM_EP_SECURITY_MASK    0x1
 
 #define UP	1
 #define DOWN	0
@@ -64,10 +63,23 @@
 #define ENTRY_POINT_INFO_PC_OFFSET	0x08
 #define ENTRY_POINT_INFO_ARGS_OFFSET	0x18
 
+#define PARAM_EP_SECURITY_MASK    0x1
 #define GET_SECURITY_STATE(x) (x & PARAM_EP_SECURITY_MASK)
 #define SET_SECURITY_STATE(x, security) \
 			((x) = ((x) & ~PARAM_EP_SECURITY_MASK) | (security))
 
+#define EP_EE_MASK	0x2
+#define EP_EE_LITTLE	0x0
+#define EP_EE_BIG	0x2
+#define EP_GET_EE(x) (x & EP_EE_MASK)
+#define EP_SET_EE(x, ee) ((x) = ((x) & ~EP_EE_MASK) | (ee))
+
+#define EP_ST_MASK	0x4
+#define EP_ST_DISABLE	0x0
+#define EP_ST_ENABLE	0x4
+#define EP_GET_ST(x) (x & EP_ST_MASK)
+#define EP_SET_ST(x, ee) ((x) = ((x) & ~EP_ST_MASK) | (ee))
+
 #define PARAM_EP     0x01
 #define PARAM_IMAGE_BINARY  0x02
 #define PARAM_BL31       0x03