-----------------------------
This document focuses on version 2 of the library, whose sources are available
-in the `lib/xlat_tables_v2`_ directory. Version 1 of the library can still be
-found in `lib/xlat_tables`_ directory but it is less flexible and doesn't
+in the ``lib/xlat_tables_v2`` directory. Version 1 of the library can still be
+found in ``lib/xlat_tables`` directory but it is less flexible and doesn't
support dynamic mapping. Although potential bug fixes will be applied to both
versions, future features enhancements will focus on version 2 and might not be
back-ported to version 1. Therefore, it is recommended to use version 2,
- its attributes;
- its mapping granularity (optional).
-See the ``struct mmap_region`` type in `xlat_tables_v2.h`_.
+See the ``struct mmap_region`` type in ``xlat_tables_v2.h``.
The user usually provides a list of such mmap regions to map and lets the
library transpose that in a set of translation tables. As a result, the library
read-write, executable or not, secure or non-secure, and so on). In the case of
the EL1&0 translation regime, the attributes also specify whether the region is
a User region (EL0) or Privileged region (EL1). See the ``MT_xxx`` definitions
-in `xlat_tables_v2.h`_. Note that for the EL1&0 translation regime the Execute
+in ``xlat_tables_v2.h``. Note that for the EL1&0 translation regime the Execute
Never attribute is set simultaneously for both EL1 and EL0.
The granularity controls the translation table level to go down to when mapping
- size of the virtual address space: ``PLAT_VIRT_ADDR_SPACE_SIZE``;
- size of the physical address space: ``PLAT_PHY_ADDR_SPACE_SIZE``.
-Please refer to the `Porting Guide`_ for more details about these macros.
+Please refer to the :ref:`Porting Guide` for more details about these macros.
Static and dynamic memory regions
------------
The external APIs exposed by this library are declared and documented in the
-`xlat_tables_v2.h`_ header file. This should be the reference point for
+``xlat_tables_v2.h`` header file. This should be the reference point for
getting information about the usage of the different APIs this library
provides. This section just provides some extra details and clarifications.
provides functions such as ``mmap_add_region_ctx`` that let the caller specify
the translation tables context affected by them.
- See `xlat_tables_core.c`_.
+ See ``xlat_tables_core.c``.
- **Active context module**
This module provides functions such as ``mmap_add_region``, that directly
affect the BL image using them.
- See `xlat_tables_context.c`_.
+ See ``xlat_tables_context.c``.
- **Utilities module**
Provides additional functionality like debug print of the current state of the
translation tables and helpers to query memory attributes and to modify them.
- See `xlat_tables_utils.c`_.
+ See ``xlat_tables_utils.c``.
- **Architectural module**
MMU, or calculate the Physical Address Space size. They do not need a
translation context to work on.
- See `aarch32/xlat_tables_arch.c`_ and `aarch64/xlat_tables_arch.c`_.
+ See ``aarch32/xlat_tables_arch.c`` and ``aarch64/xlat_tables_arch.c``.
From mmap regions to translation tables
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bound by the level of depth of the translation tables (the Armv8-A architecture
allows up to 4 lookup levels).
-By default [#granularity-ref]_, the algorithm will attempt to minimize the
+By default [#granularity]_, the algorithm will attempt to minimize the
number of translation tables created to satisfy the user's request. It will
favour mapping a region using the biggest possible blocks, only creating a
sub-table if it is strictly necessary. This is to reduce the memory footprint of
refer to the comments in the source code of the core module for more details
about the sorting algorithm in use.
-.. [#granularity-ref] That is, when mmap regions do not enforce their mapping
- granularity.
-
TLB maintenance operations
~~~~~~~~~~~~~~~~~~~~~~~~~~
invalid translation table entry [#tlb-no-invalid-entry]_, this means that this
mapping cannot be cached in the TLBs.
-.. [#tlb-reset-ref] See section D4.9 `Translation Lookaside Buffers (TLBs)`, subsection `TLB behavior at reset` in Armv8-A, rev C.a.
-.. [#tlb-no-invalid-entry] See section D4.10.1 `General TLB maintenance requirements` in Armv8-A, rev C.a.
+.. rubric:: Footnotes
+
+.. [#granularity] That is, when mmap regions do not enforce their mapping
+ granularity.
+
+.. [#tlb-reset-ref] See section D4.9 ``Translation Lookaside Buffers (TLBs)``,
+ subsection ``TLB behavior at reset`` in Armv8-A, rev C.a.
+
+.. [#tlb-no-invalid-entry] See section D4.10.1 ``General TLB maintenance
+ requirements`` in Armv8-A, rev C.a.
--------------
-*Copyright (c) 2017-2018, Arm Limited and Contributors. All rights reserved.*
-
-.. _lib/xlat_tables_v2: ../../lib/xlat_tables_v2
-.. _lib/xlat_tables: ../../lib/xlat_tables
-.. _xlat_tables_v2.h: ../../include/lib/xlat_tables/xlat_tables_v2.h
-.. _xlat_tables_context.c: ../../lib/xlat_tables_v2/xlat_tables_context.c
-.. _xlat_tables_core.c: ../../lib/xlat_tables_v2/xlat_tables_core.c
-.. _xlat_tables_utils.c: ../../lib/xlat_tables_v2/xlat_tables_utils.c
-.. _aarch32/xlat_tables_arch.c: ../../lib/xlat_tables_v2/aarch32/xlat_tables_arch.c
-.. _aarch64/xlat_tables_arch.c: ../../lib/xlat_tables_v2/aarch64/xlat_tables_arch.c
-.. _Porting Guide: ../getting_started/porting-guide.rst
+*Copyright (c) 2017-2019, Arm Limited and Contributors. All rights reserved.*
+
.. |Alignment Example| image:: ../resources/diagrams/xlat_align.png
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