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This patch introduces a build flag which allows the xlat tables
to be mapped in a read-only region within BL31 memory. It makes it
much harder for someone who has acquired the ability to write to
arbitrary secure memory addresses to gain control of the
translation tables.

The memory attributes of the descriptors describing the tables
themselves are changed to read-only secure data. This change
happens at the end of BL31 runtime setup. Until this point, the
tables have read-write permissions. This gives a window of
opportunity for changes to be made to the tables with the MMU on
(e.g. reclaiming init code). No changes can be made to the tables
with the MMU turned on from this point onwards. This change is also
enabled for sp_min and tspd.

To make all this possible, the base table was moved to .rodata. The
penalty we pay is that now .rodata must be aligned to the size of
the base table (512B alignment). Still, this is better than putting
the base table with the higher level tables in the xlat_table
section, as that would cost us a full 4KB page.

Changing the tables from read-write to read-only cannot be done with
the MMU on, as the break-before-make sequence would invalidate the
descriptor which resolves the level 3 page table where that very
descriptor is located. This would make the translation required for
writing the changes impossible, generating an MMU fault.

The caches are also flushed.
Signed-off-by: Petre-Ionut Tudor <petre-ionut.tudor@arm.com>
Change-Id: Ibe5de307e6dc94c67d6186139ac3973516430466

NOTE: AARCH32/AARCH64 macros are now deprecated in favor of __aarch64__.

All common C compilers pre-define the same macros to signal which
architecture the code is being compiled for: __arm__ for AArch32 (or
earlier versions) and __aarch64__ for AArch64. There's no need for TF-A
to define its own custom macros for this. In order to unify code with
the export headers (which use __aarch64__ to avoid another dependency),
let's deprecate the AARCH32 and AARCH64 macros and switch the code base
over to the pre-defined standard macro. (Since it is somewhat
unintuitive that __arm__ only means AArch32, let's standardize on only
using __aarch64__.)

Change-Id: Ic77de4b052297d77f38fc95f95f65a8ee70cf200
Signed-off-by: Julius Werner <jwerner@chromium.org>

Enforce full include path for includes. Deprecate old paths.

The following folders inside include/lib have been left unchanged:

- include/lib/cpus/${ARCH}
- include/lib/el3_runtime/${ARCH}

The reason for this change is that having a global namespace for
includes isn't a good idea. It defeats one of the advantages of having
folders and it introduces problems that are sometimes subtle (because
you may not know the header you are actually including if there are two
of them).

For example, this patch had to be created because two headers were
called the same way: e0ea0928 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca339

 ("Move include and
source files to logical locations"). At that time, there weren't too
many headers so it wasn't a real issue. However, time has shown that
this creates problems.

Platforms that want to preserve the way they include headers may add the
removed paths to PLAT_INCLUDES, but this is discouraged.

Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Provide new APIs to add new regions without specifying the base VA.

- `mmap_add_region_alloc_va` adds a static region to mmap choosing as
  base VA the first possible address after all the currently mapped
  regions. It is aligned to an appropriate boundary in relation to the
  size and base PA of the requested region. No attempt is made to fill
  any unused VA holes.

- `mmap_add_dynamic_region_alloc_va` it adds a region the same way as
  `mmap_add_region_alloc_va` does, but it's dynamic instead of static.

- `mmap_add_alloc_va` takes an array of non const `mmap_region_t`,
  maps them in the same way as `mmap_add_region_alloc_va` and fills
  their `base_va` field. A helper macro has been created to help create
  the array, called `MAP_REGION_ALLOC_VA`.

Change-Id: I5ef3f82ca0dfd0013d2e8034aa22f13ca528ba37
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Mark the xlat tables code only used in BL31 initialization as
__init to be reclaimed once no longer needed

Change-Id: I3106bfd994706a57c578624573bcfa525fbbd3c4
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>

Change-Id: I83de2ae3e0795e6fec3c1e5b37c441b64b0c9cb6
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The translation library is useful elsewhere. Even though this repository
doesn't exercise the EL2 support of the library, it is better to have it
here as well to make it easier to maintain.

enable_mmu_secure() and enable_mmu_direct() have been deprecated. The
functions are still present, but they are behind ERROR_DEPRECATED and
they call the new functions enable_mmu_svc_mon() and
enable_mmu_direct_svc_mon().

Change-Id: I13ad10cd048d9cc2d55e0fff9a5133671b67dcba
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Changed the names for consistency with the rest of the library. Introduced
new helpers that manipulate the active translation tables context.

Change-Id: Icaca56b67fcf6a96e88aa3c7e47411162e8e6856
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Fix defects of MISRA C-2012 rules 8.13, 10.1, 10.3, 10.4, 10.8, 11.6,
14.4, 15.7, 17.8, 20.10, 20.12, 21.1 and Directive 4.9.

Change-Id: I7ff61e71733908596dbafe2e99d99b4fce9765bd
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

This allows other parts of the code to reuse it. No functional changes.

Change-Id: Ib052ae235c422d9179958bd3016c3e678779ae9b
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The Exception Level is now detected at runtime. This means that it is not
needed to hardcode the EL used by each image.

This doesn't result in a substantial increase of the image size because
the initialization functions that aren't used are garbage-collected by
the linker.

In AArch32 the current EL has been changed from EL3 to EL1 because the
the AArch32 PL1&0 translation regime behaves more like the AArch64 EL1&0
translation regime than the EL3 one.

Change-Id: I941404299ebe7666ca17619207c923b49a55cb73
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Instead of having one big file with all the code, it's better to have
a few smaller files that are more manageable:

- xlat_tables_core.c: Code related to the core functionality of the
  library (map and unmap regions, initialize xlat context).
- xlat_tables_context.c: Instantiation of the active image context
  as well as APIs to manipulate it.
- xlat_tables_utils.c: Helper code that isn't part of the core
  functionality (change attributes, debug print messages).

Change-Id: I3ea956fc1afd7473c0bb5e7c6aab3b2e5d88c711
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>