xlat: Add support for EL0 and EL1 mappings

This patch introduces the ability of the xlat tables library to manage
EL0 and EL1 mappings from a higher exception level.

Attributes MT_USER and MT_PRIVILEGED have been added to allow the user
specify the target EL in the translation regime EL1&0.

REGISTER_XLAT_CONTEXT2 macro is introduced to allow creating a
xlat_ctx_t that targets a given translation regime (EL1&0 or EL3).

A new member is added to xlat_ctx_t to represent the translation regime
the xlat_ctx_t manages. The execute_never mask member is removed as it
is computed from existing information.

Change-Id: I95e14abc3371d7a6d6a358cc54c688aa9975c110
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/include/lib/xlat_tables/xlat_tables_defs.h b/include/lib/xlat_tables/xlat_tables_defs.h
index b0f5a04..7cb9d37 100644
--- a/include/lib/xlat_tables/xlat_tables_defs.h
+++ b/include/lib/xlat_tables/xlat_tables_defs.h
@@ -89,9 +89,22 @@
  * AP[1] bit is ignored by hardware and is
  * treated as if it is One in EL2/EL3
  */
-#define AP_RO				(U(0x1) << 5)
-#define AP_RW				(U(0x0) << 5)
+#define AP2_SHIFT			U(0x7)
+#define AP2_RO				U(0x1)
+#define AP2_RW				U(0x0)
 
+#define AP1_SHIFT			U(0x6)
+#define AP1_ACCESS_UNPRIVILEGED		U(0x1)
+#define AP1_NO_ACCESS_UNPRIVILEGED	U(0x0)
+
+/*
+ * The following definitions must all be passed to the LOWER_ATTRS() macro to
+ * get the right bitmask.
+ */
+#define AP_RO				(AP2_RO << 5)
+#define AP_RW				(AP2_RW << 5)
+#define AP_ACCESS_UNPRIVILEGED		(AP1_ACCESS_UNPRIVILEGED    << 4)
+#define AP_NO_ACCESS_UNPRIVILEGED	(AP1_NO_ACCESS_UNPRIVILEGED << 4)
 #define NS				(U(0x1) << 3)
 #define ATTR_NON_CACHEABLE_INDEX	U(0x2)
 #define ATTR_DEVICE_INDEX		U(0x1)