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During cold boot, the initial translation tables are created with data
caches disabled, so all modifications go to memory directly. After the
MMU is enabled and data cache is enabled, any modification to the tables
goes to data cache, and eventually may get flushed to memory.

If CPU0 modifies the tables while CPU1 is off, CPU0 will have the
modified tables in its data cache. When CPU1 is powered on, the MMU is
enabled, then it enables coherency, and then it enables the data cache.
Until this is done, CPU1 isn't in coherency, and the translation tables
it sees can be outdated if CPU0 still has some modified entries in its
data cache.

This can be a problem in some cases. For example, the warm boot code
uses only the tables mapped during cold boot, which don't normally
change. However, if they are modified (and a RO page is made RW, or a XN
page is made executable) the CPU will see the old attributes and crash
when it tries to access it.

This doesn't happen in systems with HW_ASSISTED_COHERENCY or
WARMBOOT_ENABLE_DCACHE_EARLY. In these systems, the data cache is
enabled at the same time as the MMU. As soon as this happens, the CPU is
in coherency.

There was an attempt of a fix in psci_helpers.S, but it didn't solve the
problem. That code has been deleted. The code was introduced in commit
<26441030

> ("Invalidate TLB entries during warm boot").

Now, during a map or unmap operation, the memory associated to each
modified table is flushed. Traversing a table will also flush it's
memory, as there is no way to tell in the current implementation if the
table that has been traversed has also been modified.

Change-Id: I4b520bca27502f1018878061bc5fb82af740bb92
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>

Change-Id: I35d5b6a7c219f6f38983b30f157c1ed3808af17f
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 library can be used in other projects. All comments that talk about
the Trusted Firmware should be talking about the library itself.

Change-Id: I3b98d42f7132be72c1f8a4900acfaa78dbd2daa2
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>

xlat_arch_tlbi_va_regime() isn't used, so it has been renamed to
xlat_arch_tlbi_va() and the previous implementation has been removed.

Change-Id: Ic118bed3fb68234748d86b2e9e95b25650289276
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

They only contained one function that is easily integrated in the private
library header and the existing architectural C files.

This also helps making the library more portable, as the Makefile of the
library now doesn't use the variable INCLUDES, which is specific to this
codebase and doesn't respect the namespace of the library.

Change-Id: I22228e6a97e9b4f346f5cd8947609263e8df71d8
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

It is useful to have LOG_LEVEL_VERBOSE because it prints the memory map
of each image, but that also means that the change_mem_attributes and
get_mem_attributes functions have verbose prints, and generate a too
long text output that hides other useful information.

As they were mostly there for debug purposes, this patch removes them.

Change-Id: I2986537377d1f78be2b79cc8a6cf230c380bdb55
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The previous debug output for EL1&0 translation regimes was too verbose,
which makes it hard to read and hides the intent behind the parameters
assigned to each region. This patch simplifies this output and makes the
outputs for EL3 and EL1&0 mostly the same. The difference is that in
EL1&0 it is specified whether the region is exclusively accessible from
EL1 (PRIV) or both EL0 and EL1 (USER).

For example:

    MEM-RW(PRIV)-NOACCESS(USER)-XN(PRIV)-XN(USER)-S
    MEM-RO(PRIV)-NOACCESS(USER)-EXEC(PRIV)-EXEC(USER)-S

After the change, it becomes this:

    MEM-RW-XN-PRIV-S
    MEM-RO-EXEC-PRIV-S

Change-Id: I15f4b99058429d42107fbf89e15f4838a9b559a5
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>

The values defined in this type are used in logical operations, which
goes against MISRA Rule 10.1: "Operands shall not be of an inappropriate
essential type".

Now, `unsigned int` is used instead. This also allows us to move the
dynamic mapping bit from 30 to 31. It was an undefined behaviour in the
past because an enum is signed by default, and bit 31 corresponds to the
sign bit. It is undefined behaviour to modify the sign bit. Now, bit 31
is free to use as it was originally meant to be.

mmap_attr_t is now defined as an `unsigned int` for backwards
compatibility.

Change-Id: I6b31218c14b9c7fdabebe432de7fae6e90a97f34
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The XN, PXN and UXN bits are part of the upper attributes, not the
lower attributes.

Change-Id: Ia5e83f06f2a8de88b551f55f1d36d694918ccbc0
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The issue can occur if end_va is equal to the max architecture address,
and when mm_cursor point to the last entry of mmap_region_t table: {0}.
The first line of the while will then be true, e.g. on AARCH32, we have:
mm_cursor->base_va (=0) + mm_cursor->size (=0) - 1 == end_va (=0xFFFFFFFF)
And the mm_cursor->size = 0 will be lesser than mm->size

A check on mm_cursor->size != 0 should be done as in the previous while,
to avoid such kind of infinite loop.

fixes arm-software/tf-issues#594
Signed-off-by: Yann Gautier <yann.gautier@st.com>

The function xlat_arch_is_granule_size_supported() can be used to check
if a specific granule size is supported. In Armv8, AArch32 only supports
4 KiB pages. AArch64 supports 4 KiB, 16 KiB or 64 KiB depending on the
implementation, which is detected at runtime.

The function xlat_arch_get_max_supported_granule_size() returns the max
granule size supported by the implementation.

Even though right now they are only used by SPM, they may be useful in
other places in the future. This patch moves the code currently in SPM
to the xlat tables lib so that it can be reused.

Change-Id: If54624a5ecf20b9b9b7f38861b56383a03bbc8a4
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

    Rule 21.15: The pointer arguments to the Standard Library functions
    memcpy, memmove and memcmp shall be pointers to qualified or unqualified
    versions of compatible types.

    Basically that means that both pointer arguments must be of the same
    type. However, even if the pointers passed as arguments to the above
    functions are of the same type, Coverity still thinks it's a violation
    if we do pointer arithmetics directly at the function call. Thus the
    pointer arithmetic operations were moved outside of the function
    argument.

    First detected on the following configuration
            make PLAT=fvp LOG_LEVEL=50

    Change-Id: I8b912ec1bfa6f2d60857cb1bd453981fd7001b94
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

Using variables as format strings can generate security problems when
the user can control those strings. Some compilers generate warnings
in that cases, even when the variables are constants and are not
controlled by the user.

Change-Id: I65dee1d1b66feab38cbf298290a86fa56e6cca40
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

In AArch64, the field ID_AA64MMFR0_EL1.PARange has a different set of
allowed values depending on the architecture version.

Previously, we only compiled the Trusted Firmware with the values that
were allowed by the architecture. However, given that this field is
read-only, it is easier to compile the code with all values regardless
of the target architecture.

Change-Id: I57597ed103dd0189b1fb738a9ec5497391c10dd1
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

According to the ARMv8 ARM issue C.a:

    AP[1] is valid only for stage 1 of a translation regime that can
    support two VA ranges. It is RES 1 when stage 1 translations can
    support only one VA range.

This means that, even though this bit is ignored, it should be set to 1
in the EL3 and EL2 translation regimes.

For translation regimes consisting on EL0 and a higher regime this bit
selects between control at EL0 or at the higher Exception level. The
regimes that support two VA ranges are EL1&0 and EL2&0 (the later one
is only available since ARMv8.1).

This fix has to be applied to both versions of the translation tables
library.

Change-Id: If19aaf588551bac7aeb6e9a686cf0c2068e7c181
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Change-Id: I989c1f4aef8e3cb20d5d19e6347575e6449bb60b
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The last entry in the mapping table is not necessarily the same as the
end of the table. This patch loops through the table to find the last
entry marker, on every new mmap addition. The memove operation then
has to only move the memory between current entry and the last entry.
For platforms that arrange their MMIO map properly, this opearation
turns out to be a NOP.

The previous implementation added significant overhead per mmap
addition as the memmove operation always moved the difference between
the current mmap entry and the end of the table.

Tested on Tegra platforms and this new approach improves the memory
mapping time by ~75%, thus significantly reducing boot time on some
platforms.

Change-Id: Ie3478fa5942379282ef58bee2085da799137e2ca
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

Rule 8.4: A compatible declaration shall be visible when
          an object or function with external linkage is defined

Fixed for:
	make DEBUG=1 PLAT=fvp LOG_LEVEL=50 all

Change-Id: I7c2ad3f5c015411c202605851240d5347e4cc8c7
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Rule 8.3: All declarations of an object or function shall
          use the same names and type qualifiers.

Change-Id: Iff384187c74a598a4e73f350a1893b60e9d16cec
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

MISRA C-2012 Rule 7.3 violation: lowercase l shall not be used as literal suffixes.

This patch resolves this for the ULL() macro by using ULL suffix instead
of the ull suffix.

Change-Id: Ia8183c399e74677e676956e8653e82375d0e0a01
Signed-off-by: David Cunado <david.cunado@arm.com>

`mm_cursor` doesn't have the needed data because the `memmove()` that
is called right before it overwrites that information. In order to get
the information of the region that was being mapped, `mm` has to be used
instead (like it is done to fill the fields of `unmap_mm`).

If the incorrect information is read, this check isn't reliable and
`xlat_tables_unmap_region` may be requested to unmap memory that isn't
mapped at all, triggering assertions.

Change-Id: I602d4ac83095d4e5dac9deb34aa5d00d00e6c289
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

If an implementation of ARMv8.2 includes ARMv8.2-LPA, the value 0b0110
is permitted in ID_AA64MMFR0_EL1.PARange, which means that the Physical
Address range supported is 52 bits (4 PiB). It is a reserved value
otherwise.

Change-Id: Ie0147218e9650aa09f0034a9ee03c1cca8db908a
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

This function can be useful to setup TCR_ELx by callers that don't use
the translation tables library to setup the system registers related
to them. By making it common, it can be reused whenever it is needed
without duplicating code.

Change-Id: Ibfada9e846d2a6cd113b1925ac911bb27327d375
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

ARCH_SUPPORTS_LARGE_PAGE_ADDRESSING allows build environment to
handle specific case when target ARMv7 core only supports 32bit MMU
descriptor mode.

If ARMv7 based platform does not set ARM_CORTEX_Ax=yes, platform
shall define ARMV7_SUPPORTS_LARGE_PAGE_ADDRESSING to enable
large page addressing support.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

This patch introduces a new API in the translation tables library
(v2), that allows to change the memory attributes of a memory
region. It may be used to change its execution permissions and
data access permissions.

As a prerequisite, the memory must be already mapped. Moreover, it
must be mapped at the finest granularity (currently 4 KB).

Change-Id: I242a8c6f0f3ef2b0a81a61e28706540462faca3c
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>

This patch introduces a new API in the translation tables library
(v2), that allows to query the memory attributes of a memory block
or a memory page.

Change-Id: I45a8b39a53da39e7617cbac4bff5658dc1b20a11
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>

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>

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: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

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: Sandrine Bailleux <sandrine.bailleux@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>

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: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

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: Douglas Raillard <douglas.raillard@arm.com>

mmap_add_region_ctx and mmap_add_dynamic_region_ctx are clearing members
that they are not aware of by copying each member one by one. Replace
this by structure assignment.

Change-Id: I7c70cb408c8a8eb551402a5d8d956c1fb7f32b55
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>