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)
diff --git a/lib/xlat_tables/xlat_tables_common.c b/lib/xlat_tables/xlat_tables_common.c
new file mode 100644
index 0000000..d686c8d
--- /dev/null
+++ b/lib/xlat_tables/xlat_tables_common.c
@@ -0,0 +1,281 @@
+/*
+ * 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.
+ */
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include <assert.h>
+#include <bl_common.h>
+#include <cassert.h>
+#include <debug.h>
+#include <platform_def.h>
+#include <string.h>
+#include <xlat_tables.h>
+
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+#define LVL0_SPACER ""
+#define LVL1_SPACER "  "
+#define LVL2_SPACER "    "
+#define LVL3_SPACER "      "
+#define get_level_spacer(level)		\
+			(((level) == 0) ? LVL0_SPACER : \
+			(((level) == 1) ? LVL1_SPACER : \
+			(((level) == 2) ? LVL2_SPACER : LVL3_SPACER)))
+#define debug_print(...) tf_printf(__VA_ARGS__)
+#else
+#define debug_print(...) ((void)0)
+#endif
+
+#define UNSET_DESC	~0ul
+
+static uint64_t xlat_tables[MAX_XLAT_TABLES][XLAT_TABLE_ENTRIES]
+			__aligned(XLAT_TABLE_SIZE) __section("xlat_table");
+
+static unsigned next_xlat;
+static unsigned long long xlat_max_pa;
+static uintptr_t xlat_max_va;
+
+/*
+ * Array of all memory regions stored in order of ascending base address.
+ * The list is terminated by the first entry with size == 0.
+ */
+static mmap_region_t mmap[MAX_MMAP_REGIONS + 1];
+
+
+void print_mmap(void)
+{
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+	debug_print("mmap:\n");
+	mmap_region_t *mm = mmap;
+	while (mm->size) {
+		debug_print(" VA:%p  PA:0x%llx  size:0x%zx  attr:0x%x\n",
+				(void *)mm->base_va, mm->base_pa,
+				mm->size, mm->attr);
+		++mm;
+	};
+	debug_print("\n");
+#endif
+}
+
+void mmap_add_region(unsigned long long base_pa, uintptr_t base_va,
+			size_t size, unsigned int attr)
+{
+	mmap_region_t *mm = mmap;
+	mmap_region_t *mm_last = mm + ARRAY_SIZE(mmap) - 1;
+	unsigned long long pa_end = base_pa + size - 1;
+	uintptr_t va_end = base_va + size - 1;
+
+	assert(IS_PAGE_ALIGNED(base_pa));
+	assert(IS_PAGE_ALIGNED(base_va));
+	assert(IS_PAGE_ALIGNED(size));
+
+	if (!size)
+		return;
+
+	/* Find correct place in mmap to insert new region */
+	while (mm->base_va < base_va && mm->size)
+		++mm;
+
+	/* Make room for new region by moving other regions up by one place */
+	memmove(mm + 1, mm, (uintptr_t)mm_last - (uintptr_t)mm);
+
+	/* Check we haven't lost the empty sentinal from the end of the array */
+	assert(mm_last->size == 0);
+
+	mm->base_pa = base_pa;
+	mm->base_va = base_va;
+	mm->size = size;
+	mm->attr = attr;
+
+	if (pa_end > xlat_max_pa)
+		xlat_max_pa = pa_end;
+	if (va_end > xlat_max_va)
+		xlat_max_va = va_end;
+}
+
+void mmap_add(const mmap_region_t *mm)
+{
+	while (mm->size) {
+		mmap_add_region(mm->base_pa, mm->base_va, mm->size, mm->attr);
+		++mm;
+	}
+}
+
+static uint64_t mmap_desc(unsigned attr, unsigned long long addr_pa,
+							int level)
+{
+	uint64_t desc = addr_pa;
+	int mem_type;
+
+	desc |= level == 3 ? TABLE_DESC : BLOCK_DESC;
+
+	desc |= attr & MT_NS ? LOWER_ATTRS(NS) : 0;
+
+	desc |= attr & MT_RW ? LOWER_ATTRS(AP_RW) : LOWER_ATTRS(AP_RO);
+
+	desc |= LOWER_ATTRS(ACCESS_FLAG);
+
+	mem_type = MT_TYPE(attr);
+	if (mem_type == MT_MEMORY) {
+		desc |= LOWER_ATTRS(ATTR_IWBWA_OWBWA_NTR_INDEX | ISH);
+		if (attr & MT_RW)
+			desc |= UPPER_ATTRS(XN);
+	} else if (mem_type == MT_NON_CACHEABLE) {
+		desc |= LOWER_ATTRS(ATTR_NON_CACHEABLE_INDEX | OSH);
+		if (attr & MT_RW)
+			desc |= UPPER_ATTRS(XN);
+	} else {
+		assert(mem_type == MT_DEVICE);
+		desc |= LOWER_ATTRS(ATTR_DEVICE_INDEX | OSH);
+		desc |= UPPER_ATTRS(XN);
+	}
+
+	debug_print((mem_type == MT_MEMORY) ? "MEM" :
+		((mem_type == MT_NON_CACHEABLE) ? "NC" : "DEV"));
+	debug_print(attr & MT_RW ? "-RW" : "-RO");
+	debug_print(attr & MT_NS ? "-NS" : "-S");
+
+	return desc;
+}
+
+static int mmap_region_attr(mmap_region_t *mm, uintptr_t base_va,
+					size_t size)
+{
+	int attr = mm->attr;
+	int old_mem_type, new_mem_type;
+
+	for (;;) {
+		++mm;
+
+		if (!mm->size)
+			return attr; /* Reached end of list */
+
+		if (mm->base_va >= base_va + size)
+			return attr; /* Next region is after area so end */
+
+		if (mm->base_va + mm->size <= base_va)
+			continue; /* Next region has already been overtaken */
+
+		if ((mm->attr & attr) == attr)
+			continue; /* Region doesn't override attribs so skip */
+
+		/*
+		 * Update memory mapping attributes in 2 steps:
+		 * 1) Update access permissions and security state flags
+		 * 2) Update memory type.
+		 *
+		 * See xlat_tables.h for details about the attributes priority
+		 * system and the rules dictating whether attributes should be
+		 * updated.
+		 */
+		old_mem_type = MT_TYPE(attr);
+		new_mem_type = MT_TYPE(mm->attr);
+		attr &= mm->attr;
+		if (new_mem_type < old_mem_type)
+			attr = (attr & ~MT_TYPE_MASK) | new_mem_type;
+
+		if (mm->base_va > base_va ||
+			mm->base_va + mm->size < base_va + size)
+			return -1; /* Region doesn't fully cover our area */
+	}
+}
+
+static mmap_region_t *init_xlation_table_inner(mmap_region_t *mm,
+					uintptr_t base_va,
+					uint64_t *table,
+					int level)
+{
+	unsigned level_size_shift = L1_XLAT_ADDRESS_SHIFT - (level - 1) *
+						XLAT_TABLE_ENTRIES_SHIFT;
+	unsigned level_size = 1 << level_size_shift;
+	unsigned long long level_index_mask = XLAT_TABLE_ENTRIES_MASK <<
+							level_size_shift;
+
+	assert(level > 0 && level <= 3);
+
+	debug_print("New xlat table:\n");
+
+	do  {
+		uint64_t desc = UNSET_DESC;
+
+		if (!mm->size) {
+			/* Done mapping regions; finish zeroing the table */
+			desc = INVALID_DESC;
+		} else if (mm->base_va + mm->size <= base_va) {
+			/* Area now after the region so skip it */
+			++mm;
+			continue;
+		}
+
+		debug_print("%s VA:%p size:0x%x ", get_level_spacer(level),
+				(void *)base_va, level_size);
+
+		if (mm->base_va >= base_va + level_size) {
+			/* Next region is after area so nothing to map yet */
+			desc = INVALID_DESC;
+		} else if (mm->base_va <= base_va && mm->base_va + mm->size >=
+				base_va + level_size) {
+			/* Next region covers all of area */
+			int attr = mmap_region_attr(mm, base_va, level_size);
+			if (attr >= 0)
+				desc = mmap_desc(attr,
+					base_va - mm->base_va + mm->base_pa,
+					level);
+		}
+		/* else Next region only partially covers area, so need */
+
+		if (desc == UNSET_DESC) {
+			/* Area not covered by a region so need finer table */
+			uint64_t *new_table = xlat_tables[next_xlat++];
+			assert(next_xlat <= MAX_XLAT_TABLES);
+			desc = TABLE_DESC | (unsigned long)new_table;
+
+			/* Recurse to fill in new table */
+			mm = init_xlation_table_inner(mm, base_va,
+						new_table, level+1);
+		}
+
+		debug_print("\n");
+
+		*table++ = desc;
+		base_va += level_size;
+	} while ((base_va & level_index_mask) && (base_va < ADDR_SPACE_SIZE));
+
+	return mm;
+}
+
+void init_xlation_table(uintptr_t base_va, uint64_t *table,
+			int level, uintptr_t *max_va,
+			unsigned long long *max_pa)
+{
+
+	init_xlation_table_inner(mmap, base_va, table, level);
+	*max_va = xlat_max_va;
+	*max_pa = xlat_max_pa;
+}
diff --git a/lib/xlat_tables/xlat_tables_private.h b/lib/xlat_tables/xlat_tables_private.h
new file mode 100644
index 0000000..389bb0b
--- /dev/null
+++ b/lib/xlat_tables/xlat_tables_private.h
@@ -0,0 +1,39 @@
+/*
+ * 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 __XLAT_TABLES_PRIVATE_H__
+#define __XLAT_TABLES_PRIVATE_H__
+
+void print_mmap(void);
+void init_xlation_table(uintptr_t base_va, uint64_t *table,
+			int level, uintptr_t *max_va,
+			unsigned long long *max_pa);
+
+#endif /* __XLAT_TABLES_PRIVATE_H__ */