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: __ASSEMBLY__ macro is now deprecated in favor of __ASSEMBLER__.
All common C compilers predefine a macro called __ASSEMBLER__ when
preprocessing a .S file. There is no reason for TF-A to define it's own
__ASSEMBLY__ macro for this purpose instead. To unify code with the
export headers (which use __ASSEMBLER__ to avoid one extra dependency),
let's deprecate __ASSEMBLY__ and switch the code base over to the
predefined standard.
Change-Id: Id7d0ec8cf330195da80499c68562b65cb5ab7417
Signed-off-by: Julius Werner <jwerner@chromium.org>
ARMv8.4-TTST (Small Translation tables) relaxes the lower limit on the
size of translation tables by increasing the maximum permitted value
of the T1SZ and T0SZ fields in TCR_EL1, TCR_EL2, TCR_EL3, VTCR_EL2 and
VSTCR_EL2.
This feature is supported in AArch64 state only.
This patch adds support for this feature to both versions of the
translation tables library. It also removes the static build time
checks for virtual address space size checks to runtime assertions.
Change-Id: I4e8cebc197ec1c2092dc7d307486616786e6c093
Signed-off-by: Sathees Balya <sathees.balya@arm.com>
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: e0ea0928d5 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a2 ("drivers: add tzc380 support").
This problem was introduced in commit 4ecca33988 ("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>
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>
Most registers are 64-bit wide, even in AArch32 mode:
- MAIR_ELx is equivalent to MAIR0 and MAIR1.
- TTBR is 64 bit in both AArch64 and AArch32.
The only difference is the TCR register, which is 32 bit in AArch32 and
in EL3 in AArch64. For consistency with the rest of ELs in AArch64, it
makes sense to also have it as a 64-bit value.
Change-Id: I2274d66a28876702e7085df5f8aad0e7ec139da9
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>
At present, the function provided by the translation library to enable
MMU constructs appropriate values for translation library, and programs
them to the right registers. The construction of initial values,
however, is only required once as both the primary and secondaries
program the same values.
Additionally, the MMU-enabling function is written in C, which means
there's an active stack at the time of enabling MMU. On some systems,
like Arm DynamIQ, having active stack while enabling MMU during warm
boot might lead to coherency problems.
This patch addresses both the above problems by:
- Splitting the MMU-enabling function into two: one that sets up
values to be programmed into the registers, and another one that
takes the pre-computed values and writes to the appropriate
registers. With this, the primary effectively calls both functions
to have the MMU enabled, but secondaries only need to call the
latter.
- Rewriting the function that enables MMU in assembly so that it
doesn't use stack.
This patch fixes a bunch of MISRA issues on the way.
Change-Id: I0faca97263a970ffe765f0e731a1417e43fbfc45
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
This patch enables BL2 to execute at the highest exception level
without any dependancy on TF BL1. This enables platforms which already
have a non-TF Boot ROM to directly load and execute BL2 and subsequent BL
stages without need for BL1. This is not currently possible because
BL2 executes at S-EL1 and cannot jump straight to EL3.
Change-Id: Ief1efca4598560b1b8c8e61fbe26d1f44e929d69
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
A new platform define, `PLAT_SP_IMAGE_XLAT_SECTION_NAME`, has been
introduced to select the section where the translation tables used by
the S-EL1/S-EL0 are placed.
This define has been used to move the translation tables to DRAM secured
by TrustZone.
Most of the extra needed space in BL31 when SPM is enabled is due to the
large size of the translation tables. By moving them to this memory
region we can save 44 KiB.
A new argument has been added to REGISTER_XLAT_CONTEXT2() to specify the
region where the translation tables have to be placed by the linker.
Change-Id: Ia81709b4227cb8c92601f0caf258f624c0467719
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
These macros are only defined for corresponding image,
and they are undefined for other images. It means that we have
to use ifdef or defined() instead of relying on being 0 by default.
Change-Id: Iad11efab9830ddf471599b46286e1c56581ef5a7
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
Previously, in AArch32, `IMAGE_XLAT_DEFAULT_REGIME` wasn't defined. The
translation regime is only used in the AArch64 port of the translation
tables library v2, so this is not a problem for now, but future patches
will use it.
`IMAGE_EL` isn't used in AArch32, so it isn't needed to define it.
Change-Id: I4acdb01a58658956ab94bd82ed5b7fee1aa6ba90
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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: Sandrine Bailleux <sandrine.bailleux@arm.com>
Petre-Ionut Tudor
Julius Werner
Sathees Balya
Antonio Nino Diaz
Jeenu Viswambharan
Roberto Vargas
Sandrine Bailleux