Refactor the xlat_tables library code

The AArch32 long descriptor format and the AArch64 descriptor format
correspond to each other which allows possible sharing of xlat_tables
library code between AArch64 and AArch32. This patch refactors the
xlat_tables library code to seperate the common functionality from
architecture specific code. Prior to this patch, all of the xlat_tables
library code were in `lib/aarch64/xlat_tables.c` file. The refactored code
is now in `lib/xlat_tables/` directory. The AArch64 specific programming
for xlat_tables is in `lib/xlat_tables/aarch64/xlat_tables.c` and the rest
of the code common to AArch64 and AArch32 is in
`lib/xlat_tables/xlat_tables_common.c`. Also the data types used in
xlat_tables library APIs are reworked to make it compatible between AArch64
and AArch32.

The `lib/aarch64/xlat_tables.c` file now includes the new xlat_tables
library files to retain compatibility for existing platform ports.
The macros related to xlat_tables library are also moved from
`include/lib/aarch64/arch.h` to the header `include/lib/xlat_tables.h`.

NOTE: THE `lib/aarch64/xlat_tables.c` FILE IS DEPRECATED AND PLATFORM PORTS
ARE EXPECTED TO INCLUDE THE NEW XLAT_TABLES LIBRARY FILES IN THEIR MAKEFILES.

Change-Id: I3d17217d24aaf3a05a4685d642a31d4d56255a0f
diff --git a/lib/xlat_tables/aarch64/xlat_tables.c b/lib/xlat_tables/aarch64/xlat_tables.c
new file mode 100644
index 0000000..051e46a
--- /dev/null
+++ b/lib/xlat_tables/aarch64/xlat_tables.c
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 2014-2016, 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.
+ */
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include <assert.h>
+#include <cassert.h>
+#include <platform_def.h>
+#include <xlat_tables.h>
+#include "../xlat_tables_private.h"
+
+#define IS_POWER_OF_TWO(x)	(((x) & ((x) - 1)) == 0)
+
+/*
+ * The virtual address space size must be a power of two (as set in TCR.T0SZ).
+ * As we start the initial lookup at level 1, it must also be between 2 GB and
+ * 512 GB (with the virtual address size therefore 31 to 39 bits). See section
+ * D4.2.5 in the ARMv8-A Architecture Reference Manual (DDI 0487A.i) for more
+ * information.
+ */
+CASSERT(ADDR_SPACE_SIZE >= (1ull << 31) && ADDR_SPACE_SIZE <= (1ull << 39) &&
+	IS_POWER_OF_TWO(ADDR_SPACE_SIZE), assert_valid_addr_space_size);
+
+#define UNSET_DESC	~0ul
+#define NUM_L1_ENTRIES (ADDR_SPACE_SIZE >> L1_XLAT_ADDRESS_SHIFT)
+
+static uint64_t l1_xlation_table[NUM_L1_ENTRIES]
+		__aligned(NUM_L1_ENTRIES * sizeof(uint64_t));
+
+static unsigned long long tcr_ps_bits;
+
+static unsigned long long calc_physical_addr_size_bits(
+					unsigned long long max_addr)
+{
+	/* Physical address can't exceed 48 bits */
+	assert((max_addr & ADDR_MASK_48_TO_63) == 0);
+
+	/* 48 bits address */
+	if (max_addr & ADDR_MASK_44_TO_47)
+		return TCR_PS_BITS_256TB;
+
+	/* 44 bits address */
+	if (max_addr & ADDR_MASK_42_TO_43)
+		return TCR_PS_BITS_16TB;
+
+	/* 42 bits address */
+	if (max_addr & ADDR_MASK_40_TO_41)
+		return TCR_PS_BITS_4TB;
+
+	/* 40 bits address */
+	if (max_addr & ADDR_MASK_36_TO_39)
+		return TCR_PS_BITS_1TB;
+
+	/* 36 bits address */
+	if (max_addr & ADDR_MASK_32_TO_35)
+		return TCR_PS_BITS_64GB;
+
+	return TCR_PS_BITS_4GB;
+}
+
+void init_xlat_tables(void)
+{
+	unsigned long long max_pa;
+	uintptr_t max_va;
+	print_mmap();
+	init_xlation_table(0, l1_xlation_table, 1, &max_va, &max_pa);
+	tcr_ps_bits = calc_physical_addr_size_bits(max_pa);
+	assert(max_va < ADDR_SPACE_SIZE);
+}
+
+/*******************************************************************************
+ * Macro generating the code for the function enabling the MMU in the given
+ * exception level, assuming that the pagetables have already been created.
+ *
+ *   _el:		Exception level at which the function will run
+ *   _tcr_extra:	Extra bits to set in the TCR register. This mask will
+ *			be OR'ed with the default TCR value.
+ *   _tlbi_fct:		Function to invalidate the TLBs at the current
+ *			exception level
+ ******************************************************************************/
+#define DEFINE_ENABLE_MMU_EL(_el, _tcr_extra, _tlbi_fct)		\
+	void enable_mmu_el##_el(unsigned int flags)				\
+	{								\
+		uint64_t mair, tcr, ttbr;				\
+		uint32_t sctlr;						\
+									\
+		assert(IS_IN_EL(_el));					\
+		assert((read_sctlr_el##_el() & SCTLR_M_BIT) == 0);	\
+									\
+		/* Set attributes in the right indices of the MAIR */	\
+		mair = MAIR_ATTR_SET(ATTR_DEVICE, ATTR_DEVICE_INDEX);	\
+		mair |= MAIR_ATTR_SET(ATTR_IWBWA_OWBWA_NTR,		\
+				ATTR_IWBWA_OWBWA_NTR_INDEX);		\
+		mair |= MAIR_ATTR_SET(ATTR_NON_CACHEABLE,		\
+				ATTR_NON_CACHEABLE_INDEX);		\
+		write_mair_el##_el(mair);				\
+									\
+		/* Invalidate TLBs at the current exception level */	\
+		_tlbi_fct();						\
+									\
+		/* Set TCR bits as well. */				\
+		/* Inner & outer WBWA & shareable + T0SZ = 32 */	\
+		tcr = TCR_SH_INNER_SHAREABLE | TCR_RGN_OUTER_WBA |	\
+			TCR_RGN_INNER_WBA |				\
+			(64 - __builtin_ctzl(ADDR_SPACE_SIZE));		\
+		tcr |= _tcr_extra;					\
+		write_tcr_el##_el(tcr);					\
+									\
+		/* Set TTBR bits as well */				\
+		ttbr = (uint64_t) l1_xlation_table;			\
+		write_ttbr0_el##_el(ttbr);				\
+									\
+		/* Ensure all translation table writes have drained */	\
+		/* into memory, the TLB invalidation is complete, */	\
+		/* and translation register writes are committed */	\
+		/* before enabling the MMU */				\
+		dsb();							\
+		isb();							\
+									\
+		sctlr = read_sctlr_el##_el();				\
+		sctlr |= SCTLR_WXN_BIT | SCTLR_M_BIT;			\
+									\
+		if (flags & DISABLE_DCACHE)				\
+			sctlr &= ~SCTLR_C_BIT;				\
+		else							\
+			sctlr |= SCTLR_C_BIT;				\
+									\
+		write_sctlr_el##_el(sctlr);				\
+									\
+		/* Ensure the MMU enable takes effect immediately */	\
+		isb();							\
+	}
+
+/* Define EL1 and EL3 variants of the function enabling the MMU */
+DEFINE_ENABLE_MMU_EL(1,
+		(tcr_ps_bits << TCR_EL1_IPS_SHIFT),
+		tlbivmalle1)
+DEFINE_ENABLE_MMU_EL(3,
+		TCR_EL3_RES1 | (tcr_ps_bits << TCR_EL3_PS_SHIFT),
+		tlbialle3)