1. 05 Oct, 2017 4 commits
    • Antonio Nino Diaz's avatar
      xlat: Add support for EL0 and EL1 mappings · 609c9191
      Antonio Nino Diaz authored
      
      
      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: default avatarDouglas Raillard <douglas.raillard@arm.com>
      Co-authored-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      Co-authored-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      609c9191
    • Douglas Raillard's avatar
      xlat: Introduce function xlat_arch_tlbi_va_regime() · b4ae615b
      Douglas Raillard authored
      
      
      Introduce a variant of the TLB invalidation helper function that
      allows the targeted translation regime to be specified, rather than
      defaulting to the current one.
      
      This new function is useful in the context of EL3 software managing
      translation tables for the S-EL1&0 translation regime, as then it
      might need to invalidate S-EL1&0 TLB entries rather than EL3 ones.
      
      Define a new enumeration to be able to represent translation regimes in
      the xlat tables library.
      
      Change-Id: Ibe4438dbea2d7a6e7470bfb68ff805d8bf6b07e5
      Co-authored-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      Co-authored-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      Co-authored-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      b4ae615b
    • Sandrine Bailleux's avatar
      xlat: Always compile TLB invalidation functions · f301da44
      Sandrine Bailleux authored
      
      
      TLB invalidation functions used to be conditionally compiled in.
      They were enabled only when using the dynamic mapping feature.
      because only then would we need to modify page tables on the fly.
      
      Actually there are other use cases where invalidating TLBs is required.
      When changing memory attributes in existing translation descriptors for
      example. These other use cases do not necessarily depend on the dynamic
      mapping feature.
      
      This patch removes this dependency and always compile TLB invalidation
      functions in. If they're not used, they will be removed from the binary
      at link-time anyway so there's no consequence on the memory footprint
      if these functions are not called.
      
      Change-Id: I1c33764ae900eb00073ee23b7d0d53d4efa4dd21
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      f301da44
    • Sandrine Bailleux's avatar
      xlat: Introduce MAP_REGION2() macro · fdb1964c
      Sandrine Bailleux authored
      
      
      The current implementation of the memory mapping API favours mapping
      memory regions using the biggest possible block size in order to
      reduce the number of translation tables needed.
      
      In some cases, this behaviour might not be desirable. When translation
      tables are edited at run-time, coarse-grain mappings like that might
      need splitting into finer-grain tables. This operation has a
      performance cost.
      
      The MAP_REGION2() macro allows to specify the granularity of
      translation tables used for the initial mapping of a memory region.
      This might increase performance for memory regions that are likely to
      be edited in the future, at the expense of a potentially increased
      memory footprint.
      
      The Translation Tables Library Design Guide has been updated to
      explain the use case for this macro. Also added a few intermediate
      titles to make the guide easier to digest.
      
      Change-Id: I04de9302e0ee3d326b8877043a9f638766b81b7b
      Co-authored-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      Co-authored-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      fdb1964c
  2. 21 Sep, 2017 2 commits
    • Antonio Nino Diaz's avatar
      Set TCR_EL1.EPD1 bit to 1 · 3388b38d
      Antonio Nino Diaz authored
      
      
      In the S-EL1&0 translation regime we aren't using the higher VA range,
      whose translation table base address is held in TTBR1_EL1. The bit
      TCR_EL1.EPD1 can be used to disable translations using TTBR1_EL1, but
      the code wasn't setting it to 1. Additionally, other fields in TCR1_EL1
      associated with the higher VA range (TBI1, TG1, SH1, ORGN1, IRGN1 and
      A1) weren't set correctly as they were left as 0. In particular, 0 is a
      reserved value for TG1. Also, TBBR1_EL1 was not explicitly set and its
      reset value is UNKNOWN.
      
      Therefore memory accesses to the higher VA range would result in
      unpredictable behaviour as a translation table walk would be attempted
      using an UNKNOWN value in TTBR1_EL1.
      
      On the FVP and Juno platforms accessing the higher VA range resulted in
      a translation fault, but this may not always be the case on all
      platforms.
      
      This patch sets the bit TCR_EL1.EPD1 to 1 so that any kind of
      unpredictable behaviour is prevented.
      
      This bug only affects the AArch64 version of the code, the AArch32
      version sets this bit to 1 as expected.
      
      Change-Id: I481c000deda5bc33a475631301767b9e0474a303
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      3388b38d
    • Douglas Raillard's avatar
      xlat: simplify mmap_add_region_check parameters (#1101) · df312c5a
      Douglas Raillard authored
      
      
      Use a mmap_region_t as parameter instead of getting a parameter for each
      structure member. This reduces the scope of changes when adding members
      to mmap_region_t.
      
      Also align on the convention of using mm_cursor as a variable name for
      the currently inspected region when iterating on the region array.
      
      Change-Id: If40bc4351b56c64b214e60dda27276d11ce9dbb3
      Signed-off-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      df312c5a
  3. 14 Sep, 2017 1 commit
  4. 11 Sep, 2017 1 commit
    • Douglas Raillard's avatar
      xlat: Use MAP_REGION macro as compatibility layer · 769d65da
      Douglas Raillard authored
      
      
      Use the MAP_REGION to build the mmap_region_t argument in wrappers like
      mmap_add_region(). Evolution of the mmap_region_t might require adding
      new members with a non-zero default value. Users of MAP_REGION are
      protected against such evolution. This commit also protects users of
      mmap_add_region() and mmap_add_dynamic_region() functions against these
      evolutions.
      
      Also make the MAP_REGION macro implementation more explicit and make it
      a mmap_region_t compound literal to make it useable as a function
      parameter on its own and to prevent using it in initialization of
      variables of different type.
      
      Change-Id: I7bfc4689f6dd4dd23c895b65f628d8ee991fc161
      Signed-off-by: default avatarDouglas Raillard <douglas.raillard@arm.com>
      769d65da
  5. 24 Aug, 2017 1 commit
    • Isla Mitchell's avatar
      Enable CnP bit for ARMv8.2 CPUs · 9fce2725
      Isla Mitchell authored
      
      
      This patch enables the CnP (Common not Private) bit for secure page
      tables so that multiple PEs in the same Inner Shareable domain can use
      the same translation table entries for a given stage of translation in
      a particular translation regime. This only takes effect when ARM
      Trusted Firmware is built with ARM_ARCH_MINOR >= 2.
      
      ARM Trusted Firmware Design has been updated to include a description
      of this feature usage.
      
      Change-Id: I698305f047400119aa1900d34c65368022e410b8
      Signed-off-by: default avatarIsla Mitchell <isla.mitchell@arm.com>
      9fce2725
  6. 01 Aug, 2017 1 commit
  7. 26 Jul, 2017 5 commits
    • Sandrine Bailleux's avatar
      xlat lib: Fix some types · 0044231d
      Sandrine Bailleux authored
      Fix the type length and signedness of some of the constants and
      variables used in the translation table library.
      
      This patch supersedes Pull Request #1018:
      https://github.com/ARM-software/arm-trusted-firmware/pull/1018
      
      
      
      Change-Id: Ibd45faf7a4fb428a0bf71c752551d35800212fb2
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      0044231d
    • Sandrine Bailleux's avatar
      xlat lib v2: Remove hard-coded virtual address space size · 347621bb
      Sandrine Bailleux authored
      
      
      Previous patches have made it possible to specify the physical and
      virtual address spaces sizes for each translation context. However,
      there are still some places in the code where the physical (resp.
      virtual) address space size is assumed to be PLAT_PHY_ADDR_SPACE_SIZE
      (resp. PLAT_VIRT_ADDR_SPACE_SIZE).
      
      This patch removes them and reads the relevant address space size
      from the translation context itself instead. This information is now
      passed in argument to the enable_mmu_arch() function, which needs it
      to configure the TCR_ELx.T0SZ field (in AArch64) or the TTBCR.T0SZ
      field (in AArch32) appropriately.
      
      Change-Id: I20b0e68b03a143e998695d42911d9954328a06aa
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      347621bb
    • Sandrine Bailleux's avatar
      xlat lib v2: Refactor the functions enabling the MMU · d83f3579
      Sandrine Bailleux authored
      
      
      This patch refactors both the AArch32 and AArch64 versions of the
      function enable_mmu_arch().
      
      In both versions, the code now computes the VMSA-related system
      registers upfront then program them in one go (rather than interleaving
      the 2).
      
      In the AArch64 version, this allows to reduce the amount of code
      generated by the C preprocessor and limits it to the actual differences
      between EL1 and EL3.
      
      In the AArch32 version, this patch also removes the function
      enable_mmu_internal_secure() and moves its code directly inside
      enable_mmu_arch(), as it was its only caller.
      
      Change-Id: I35c09b6db4404916cbb2e2fd3fda2ad59f935954
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      d83f3579
    • Sandrine Bailleux's avatar
      xlat lib v2: Remove init_xlat_tables_arch() function · 99f60798
      Sandrine Bailleux authored
      
      
      In both the AArch32 and AArch64 versions, this function used to check
      the sanity of the PLAT_PHY_ADDR_SPACE_SIZE in regard to the
      architectural maximum value. Instead, export the
      xlat_arch_get_max_supported_pa() function and move the debug
      assertion in AArch-agnostic code.
      
      The AArch64 used to also precalculate the TCR.PS field value, based
      on the size of the physical address space. This is now done directly
      by enable_mmu_arch(), which now receives the physical address space size
      in argument.
      
      Change-Id: Ie77ea92eb06db586f28784fdb479c6e27dd1acc1
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      99f60798
    • Sandrine Bailleux's avatar
      xlat lib v2: Expose *_ctx() APIs · a9ad848c
      Sandrine Bailleux authored
      
      
      In a previous patch, the xlat_ctx_t type has been made public.
      This patch now makes the *_ctx() APIs public.
      
      Each API now has a *_ctx() variant. Most of them were already implemented
      and this patch just makes them public. However, some of them were missing
      so this patch introduces them.
      
      Now that all these APIs are public, there's no good reason for splitting
      them accross 2 files (xlat_tables_internal.c and xlat_tables_common.c).
      Therefore, this patch moves all code into xlat_tables_internal.c and
      removes xlat_tables_common.c. It removes it from the library's makefile
      as well.
      
      This last change introduces a compatibility break for platform ports
      that specifically include the xlat_tables_common.c file instead of
      including the library's Makefile. The UniPhier platform makefile has
      been updated to now omit this file from the list of source files.
      
      The prototype of mmap_add_region_ctx() has been slightly changed. The
      mmap_region_t passed in argument needs to be constant because it gets
      called from map_add(), which receives a constant region. The former
      implementation of mmap_add() used to cast the const qualifier away,
      which is not a good practice.
      
      Also remove init_xlation_table(), which was a sub-function of
      init_xlat_tables(). Now there's just init_xlat_tables() (and
      init_xlat_tables_ctx()). Both names were too similar, which was
      confusing. Besides, now that all the code is in a single file,
      it's no longer needed to have 2 functions for that.
      
      Change-Id: I4ed88c68e44561c3902fbebb89cb197279c5293b
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      a9ad848c
  8. 25 Jul, 2017 3 commits
    • Sandrine Bailleux's avatar
      xlat lib v2: Export translation context as an opaque type · 55c84964
      Sandrine Bailleux authored
      
      
      At the moment, the translation context type (xlat_ctx_t) is a private
      type reserved for the internal usage of the translation table library.
      All exported APIs (implemented in xlat_tables_common.c) are wrappers
      over the internal implementations that use such a translation context.
      
      These wrappers unconditionally pass the current translation context
      representing the memory mappings of the executing BL image. This means
      that the caller has no control over which translation context the
      library functions act on.
      
      As a first step to make this code more flexible, this patch exports
      the 'xlat_ctx_t' type. Note that, although the declaration of this type
      is now public, its definition stays private. A macro is introduced to
      statically allocate and initialize such a translation context.
      
      The library now internally uses this macro to allocate the default
      translation context for the running BL image.
      
      Change-Id: Icece1cde4813fac19452c782b682c758142b1489
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      55c84964
    • Sandrine Bailleux's avatar
      xlat lib: Reorganize architectural defs · 8933c34b
      Sandrine Bailleux authored
      
      
      Move the header files that provide translation tables architectural
      definitions from the library v2 source files to the library include
      directory. This allows to share these definitions between both
      versions (v1 and v2) of the library.
      
      Create a new header file that includes the AArch32 or AArch64
      definitions based on the AARCH32 build flag, so that the library user
      doesn't have to worry about handling it on their side.
      
      Also repurpose some of the definitions the header files provide to
      concentrate on the things that differ between AArch32 and AArch64.
      As a result they now contain the following information:
       - the first table level that allows block descriptors;
       - the architectural limits of the virtual address space;
       - the initial lookup level to cover the entire address space.
      
      Additionally, move the XLAT_TABLE_LEVEL_MIN macro from
      xlat_tables_defs.h to the AArch32/AArch64 architectural definitions.
      
      This new organisation eliminates duplicated information in the AArch32
      and AArch64 versions. It also decouples these architectural files from
      any platform-specific information. Previously, they were dependent on
      the address space size, which is platform-specific.
      
      Finally, for the v2 of the library, move the compatibility code for
      ADDR_SPACE_SIZE into a C file as it is not needed outside of this
      file. For v1, this code hasn't been changed and stays in a header
      file because it's needed by several files.
      
      Change-Id: If746c684acd80eebf918abd3ab6e8481d004ac68
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      8933c34b
    • Sandrine Bailleux's avatar
      xlat lib v2: Print some debug statistics · 0350bc6d
      Sandrine Bailleux authored
      
      
      This patch adds some debug prints to display some statistics about page
      tables usage. They are printed only if the LOG_LEVEL is at least 50
      (i.e. VERBOSE).
      
      Sample output for BL1:
      
      VERBOSE:    Translation tables state:
      VERBOSE:      Max allowed PA:  0xffffffff
      VERBOSE:      Max allowed VA:  0xffffffff
      VERBOSE:      Max mapped PA:   0x7fffffff
      VERBOSE:      Max mapped VA:   0x7fffffff
      VERBOSE:      Initial lookup level: 1
      VERBOSE:      Entries @initial lookup level: 4
      VERBOSE:      Used 4 sub-tables out of 5 (spare: 1)
      
      Change-Id: If38956902e9616cdcd6065ecd140fe21482597ea
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      0350bc6d
  9. 22 Jun, 2017 1 commit
    • Dimitris Papastamos's avatar
      aarch32: Apply workaround for errata 813419 of Cortex-A57 · 6f512a3d
      Dimitris Papastamos authored
      
      
      TLBI instructions for monitor mode won't have the desired effect under
      specific circumstances in Cortex-A57 r0p0. The workaround is to
      execute DSB and TLBI twice each time.
      
      Even though this errata is only needed in r0p0, the current errata
      framework is not prepared to apply run-time workarounds. The current one
      is always applied if compiled in, regardless of the CPU or its revision.
      
      The `DSB` instruction used when initializing the translation tables has
      been changed to `DSB ISH` as an optimization and to be consistent with
      the barriers used for the workaround.
      
      NOTE: This workaround is present in AArch64 TF and already enabled by
      default on Juno.
      
      Change-Id: I10b0baa304ed64b13b7b26ea766e61461e759dfa
      Signed-off-by: default avatarDimitris Papastamos <dimitris.papastamos@arm.com>
      6f512a3d
  10. 20 Jun, 2017 1 commit
  11. 14 Jun, 2017 1 commit
  12. 18 May, 2017 1 commit
  13. 09 May, 2017 1 commit
  14. 03 May, 2017 1 commit
  15. 02 May, 2017 1 commit
    • Antonio Nino Diaz's avatar
      Fix execute-never permissions in xlat tables libs · a5640252
      Antonio Nino Diaz authored
      
      
      Translation regimes that only support one virtual address space (such as
      the ones for EL2 and EL3) can flag memory regions as execute-never by
      setting to 1 the XN bit in the Upper Attributes field in the translation
      tables descriptors. Translation regimes that support two different
      virtual address spaces (such as the one shared by EL1 and EL0) use bits
      PXN and UXN instead.
      
      The Trusted Firmware runs at EL3 and EL1, it has to handle translation
      tables of both translation regimes, but the previous code handled both
      regimes the same way, as if both had only 1 VA range.
      
      When trying to set a descriptor as execute-never it would set the XN
      bit correctly in EL3, but it would set the XN bit in EL1 as well. XN is
      at the same bit position as UXN, which means that EL0 was being
      prevented from executing code at this region, not EL1 as the code
      intended. Therefore, the PXN bit was unset to 0 all the time. The result
      is that, in AArch64 mode, read-only data sections of BL2 weren't
      protected from being executed.
      
      This patch adds support of translation regimes with two virtual address
      spaces to both versions of the translation tables library, fixing the
      execute-never permissions for translation tables in EL1.
      
      The library currently does not support initializing translation tables
      for EL0 software, therefore it does not set/unset the UXN bit. If EL1
      software needs to initialize translation tables for EL0 software, it
      should use a different library instead.
      
      Change-Id: If27588f9820ff42988851d90dc92801c8ecbe0c9
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      a5640252
  16. 29 Apr, 2017 1 commit
    • Scott Branden's avatar
      Move defines in utils.h to utils_def.h to fix shared header compile issues · 53d9c9c8
      Scott Branden authored
      
      
      utils.h is included in various header files for the defines in it.
      Some of the other header files only contain defines.  This allows the
      header files to be shared between host and target builds for shared defines.
      
      Recently types.h has been included in utils.h as well as some function
      prototypes.
      
      Because of the inclusion of types.h conflicts exist building host tools
      abd these header files now.  To solve this problem,
      move the defines to utils_def.h and have this included by utils.h and
      change header files to only include utils_def.h and not pick up the new
      types.h being introduced.
      
      Fixes ARM-software/tf-issues#461
      Signed-off-by: default avatarScott Branden <scott.branden@broadcom.com>
      
      Remove utils_def.h from utils.h
      
      This patch removes utils_def.h from utils.h as it is not required.
      And also makes a minor change to ensure Juno platform compiles.
      
      Change-Id: I10cf1fb51e44a8fa6dcec02980354eb9ecc9fa29
      53d9c9c8
  17. 20 Apr, 2017 2 commits
    • Sandrine Bailleux's avatar
      xlat lib: Use mmap_attr_t type consistently · 28fa2e9e
      Sandrine Bailleux authored
      
      
      This patch modifies both versions of the translation table library
      to use the mmap_attr_t type consistently wherever it is manipulating
      MT_* attributes variables. It used to use mmap_attr_t or plain integer
      types interchangeably, which compiles fine because an enumeration type
      can be silently converted to an integer, but which is semantically
      incorrect.
      
      This patch removes this assumption by using the abstract type
      'mmap_attr_t' all the time.
      
      Change-Id: Id1f099025d2cb962b275bb7e39ad2c4dbb4e366c
      Signed-off-by: default avatarSandrine Bailleux <sandrine.bailleux@arm.com>
      28fa2e9e
    • Antonio Nino Diaz's avatar
      Control inclusion of helper code used for asserts · aa61368e
      Antonio Nino Diaz authored
      
      
      Many asserts depend on code that is conditionally compiled based on the
      DEBUG define. This patch modifies the conditional inclusion of such code
      so that it is based on the ENABLE_ASSERTIONS build option.
      
      Change-Id: I6406674788aa7e1ad7c23d86ce94482ad3c382bd
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      aa61368e
  18. 28 Mar, 2017 1 commit
  19. 08 Mar, 2017 4 commits
    • Antonio Nino Diaz's avatar
      Apply workaround for errata 813419 of Cortex-A57 · ccbec91c
      Antonio Nino Diaz authored
      
      
      TLBI instructions for EL3 won't have the desired effect under specific
      circumstances in Cortex-A57 r0p0. The workaround is to execute DSB and
      TLBI twice each time.
      
      Even though this errata is only needed in r0p0, the current errata
      framework is not prepared to apply run-time workarounds. The current one
      is always applied if compiled in, regardless of the CPU or its revision.
      
      This errata has been enabled for Juno.
      
      The `DSB` instruction used when initializing the translation tables has
      been changed to `DSB ISH` as an optimization and to be consistent with
      the barriers used for the workaround.
      
      Change-Id: Ifc1d70b79cb5e0d87e90d88d376a59385667d338
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      ccbec91c
    • Antonio Nino Diaz's avatar
      Add dynamic region support to xlat tables lib v2 · 0b64f4ef
      Antonio Nino Diaz authored
      
      
      Added APIs to add and remove regions to the translation tables
      dynamically while the MMU is enabled. Only static regions are allowed
      to overlap other static ones (for backwards compatibility).
      
      A new private attribute (MT_DYNAMIC / MT_STATIC) has been added to
      flag each region as such.
      
      The dynamic mapping functionality can be enabled or disabled when
      compiling by setting the build option PLAT_XLAT_TABLES_DYNAMIC to 1
      or 0. This can be done per-image.
      
      TLB maintenance code during dynamic table mapping and unmapping has
      also been added.
      
      Fixes ARM-software/tf-issues#310
      
      Change-Id: I19e8992005c4292297a382824394490c5387aa3b
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      0b64f4ef
    • Antonio Nino Diaz's avatar
      Improve debug output of the translation tables · f10644c5
      Antonio Nino Diaz authored
      
      
      The printed output has been improved in two ways:
      
      - Whenever multiple invalid descriptors are found, only the first one
        is printed, and a line is added to inform about how many descriptors
        have been omitted.
      
      - At the beginning of each line there is an indication of the table
        level the entry belongs to. Example of the new output:
        `[LV3] VA:0x1000 PA:0x1000 size:0x1000 MEM-RO-S-EXEC`
      
      Change-Id: Ib6f1cd8dbd449452f09258f4108241eb11f8d445
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      f10644c5
    • Antonio Nino Diaz's avatar
      Add version 2 of xlat tables library · 7bb01fb2
      Antonio Nino Diaz authored
      
      
      The folder lib/xlat_tables_v2 has been created to store a new version
      of the translation tables library for further modifications in patches
      to follow. At the moment it only contains a basic implementation that
      supports static regions.
      
      This library allows different translation tables to be modified by
      using different 'contexts'. For now, the implementation defaults to
      the translation tables used by the current image, but it is possible
      to modify other tables than the ones in use.
      
      Added a new API to print debug information for the current state of
      the translation tables, rather than printing the information while
      the tables are being created. This allows subsequent debug printing
      of the xlat tables after they have been changed, which will be useful
      when dynamic regions are implemented in a patch to follow.
      
      The common definitions stored in `xlat_tables.h` header have been moved
      to a new file common to both versions, `xlat_tables_defs.h`.
      
      All headers related to the translation tables library have been moved to
      a the subfolder `xlat_tables`.
      
      Change-Id: Ia55962c33e0b781831d43a548e505206dffc5ea9
      Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
      7bb01fb2