AArch32: Add support in TF libraries

This patch adds AArch32 support to cpu ops, context management,
per-cpu data and spinlock libraries. The `entrypoint_info`
structure is modified to add support for AArch32 register
arguments. The CPU operations for AEM generic cpu in AArch32
mode is also added.

Change-Id: I1e52e79f498661d8f31f1e7b3a29e222bc7a4483
diff --git a/include/lib/el3_runtime/aarch32/context.h b/include/lib/el3_runtime/aarch32/context.h
new file mode 100644
index 0000000..5108141
--- /dev/null
+++ b/include/lib/el3_runtime/aarch32/context.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __CONTEXT_H__
+#define __CONTEXT_H__
+
+/*******************************************************************************
+ * Constants that allow assembler code to access members of and the 'regs'
+ * structure at their correct offsets.
+ ******************************************************************************/
+#define CTX_REGS_OFFSET		0x0
+#define CTX_GPREG_R0		0x0
+#define CTX_GPREG_R1		0x4
+#define CTX_GPREG_R2		0x8
+#define CTX_GPREG_R3		0xC
+#define CTX_LR			0x10
+#define CTX_SCR			0x14
+#define CTX_SPSR		0x18
+#define CTX_NS_SCTLR		0x1C
+#define CTX_REGS_END		0x20
+
+#ifndef __ASSEMBLY__
+
+#include <cassert.h>
+#include <stdint.h>
+
+/*
+ * Common constants to help define the 'cpu_context' structure and its
+ * members below.
+ */
+#define WORD_SHIFT		2
+#define DEFINE_REG_STRUCT(name, num_regs)	\
+	typedef struct name {			\
+		uint32_t _regs[num_regs];	\
+	}  __aligned(8) name##_t
+
+/* Constants to determine the size of individual context structures */
+#define CTX_REG_ALL		(CTX_REGS_END >> WORD_SHIFT)
+
+DEFINE_REG_STRUCT(regs, CTX_REG_ALL);
+
+#undef CTX_REG_ALL
+
+#define read_ctx_reg(ctx, offset)	((ctx)->_regs[offset >> WORD_SHIFT])
+#define write_ctx_reg(ctx, offset, val)	(((ctx)->_regs[offset >> WORD_SHIFT]) \
+					 = val)
+typedef struct cpu_context {
+	regs_t regs_ctx;
+} cpu_context_t;
+
+/* Macros to access members of the 'cpu_context_t' structure */
+#define get_regs_ctx(h)		(&((cpu_context_t *) h)->regs_ctx)
+
+/*
+ * Compile time assertions related to the 'cpu_context' structure to
+ * ensure that the assembler and the compiler view of the offsets of
+ * the structure members is the same.
+ */
+CASSERT(CTX_REGS_OFFSET == __builtin_offsetof(cpu_context_t, regs_ctx), \
+	assert_core_context_regs_offset_mismatch);
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __CONTEXT_H__ */