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This patch introduces setjmp() and ongjmp() primitives to enable
standard setjmp/longjmp style execution. Both APIs parameters take a
pointer to struct jmpbuf type, which hosts CPU registers saved/restored
during jump.

As per the standard usage:

  - setjmp() return 0 when a jump is setup; and a non-zero value when
    returning from jump.

  - The caller of setjmp() must not return, or otherwise update stack
    pointer since.

Change-Id: I4af1d32e490cfa547979631b762b4cba188d0551
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Currently TF-A doesn't initialise CNTFRQ register in CNTCTLBase
frame of the system timer. ARM ARM states that "The instance of
the register in the CNTCTLBase frame must be programmed with this
value as part of system initialization."

The psci_arch_setup() updates the CNTFRQ system register but
according to the ARM ARM, this instance of the register is
independent of the memory mapped instance. This is only an issue
for Normal world software which relies on the memory mapped
instance rather than the system register one.

This patch resolves the issue for ARM platforms.

The patch also solves a related issue on Juno, wherein
CNTBaseN.CNTFRQ can be written and does not reflect the value of
the register in CNTCTLBase frame. Hence this patch additionally
updates CNTFRQ register in the Non Secure frame of the CNTBaseN.

Fixes ARM-Software/tf-issues#593

Change-Id: I09cebb6633688b34d5b1bc349fbde4751025b350
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

The ARMv8.4 RAS extensions introduce architectural support for software
to inject faults into the system in order to test fault-handling
software. This patch introduces the build option FAULT_HANDLING_SUPPORT
to allow for lower ELs to use registers in the Standard Error Record to
inject fault. The build option RAS_EXTENSIONS must also be enabled along
with fault injection.

This feature is intended for testing purposes only, and is advisable to
keep disabled for production images.

Change-Id: I6f7a4454b15aec098f9505a10eb188c2f928f7ea
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

The ARMv8 RAS Extensions introduced Standard Error Records which are a
set of standard registers through which:

  - Platform can configure RAS node policy; e.g., notification
    mechanism;

  - RAS nodes can record and expose error information for error handling
    agents.

Standard Error Records can either be accessed via. memory-mapped
or System registers. This patch adds helper functions to access
registers and fields within an error record.

Change-Id: I6594ba799f4a1789d7b1e45b3e17fd40e7e0ba5c
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

RAS extensions are mandatory for ARMv8.2 CPUs, but are also optional
extensions to base ARMv8.0 architecture.

This patch adds build system support to enable RAS features in ARM
Trusted Firmware. A boolean build option RAS_EXTENSION is introduced for
this.

With RAS_EXTENSION, an Exception Synchronization Barrier (ESB) is
inserted at all EL3 vector entry and exit. ESBs will synchronize pending
external aborts before entering EL3, and therefore will contain and
attribute errors to lower EL execution. Any errors thus synchronized are
detected via. DISR_EL1 register.

When RAS_EXTENSION is set to 1, HANDLE_EL3_EA_FIRST must also be set to 1.

Change-Id: I38a19d84014d4d8af688bd81d61ba582c039383a
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

At present, any External Abort routed to EL3 is reported as an unhandled
exception and cause a panic. This patch enables ARM Trusted Firmware to
handle External Aborts routed to EL3.

With this patch, when an External Abort is received at EL3, its handling
is delegated to plat_ea_handler() function. Platforms can provide their
own implementation of this function. This patch adds a weak definition
of the said function that prints out a message and just panics.

In order to support handling External Aborts at EL3, the build option
HANDLE_EA_EL3_FIRST must be set to 1.

Before this patch, HANDLE_EA_EL3_FIRST wasn't passed down to
compilation; this patch fixes that too.

Change-Id: I4d07b7e65eb191ff72d63b909ae9512478cd01a1
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

u_register_t is preferred rather than uint64_t.  This is more
consistent with the aarch32 implementation.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

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

When the source code says 'SMCC' it is talking about the SMC Calling
Convention. The correct acronym is SMCCC. This affects a few definitions
and file names.

Some files have been renamed (smcc.h, smcc_helpers.h and smcc_macros.S)
but the old files have been kept for compatibility, they include the
new ones with an ERROR_DEPRECATED guard.

Change-Id: I78f94052a502436fdd97ca32c0fe86bd58173f2f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Add some AMU helper functions to allow configuring, reading and
writing of the Group 0 and Group 1 counters.  Documentation for these
helpers will come in a separate patch.

Change-Id: I656e070d2dae830c22414f694aa655341d4e2c40
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

If the CSV2 field reads as 1 then branch targets trained in one
context cannot affect speculative execution in a different context.
In that case skip the workaround on Cortex A75.

Change-Id: I4d5504cba516a67311fb5f0657b08f72909cbd38
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Invalidate the Branch Target Buffer (BTB) on entry to EL3 by
temporarily dropping into AArch32 Secure-EL1 and executing the
`BPIALL` instruction.

This is achieved by using 3 vector tables.  There is the runtime
vector table which is used to handle exceptions and 2 additional
tables which are required to implement this workaround.  The
additional tables are `vbar0` and `vbar1`.

The sequence of events for handling a single exception is
as follows:

1) Install vector table `vbar0` which saves the CPU context on entry
   to EL3 and sets up the Secure-EL1 context to execute in AArch32 mode
   with the MMU disabled and I$ enabled.  This is the default vector table.

2) Before doing an ERET into Secure-EL1, switch vbar to point to
   another vector table `vbar1`.  This is required to restore EL3 state
   when returning from the workaround, before proceeding with normal EL3
   exception handling.

3) While in Secure-EL1, the `BPIALL` instruction is executed and an
   SMC call back to EL3 is performed.

4) On entry to EL3 from Secure-EL1, the saved context from step 1) is
   restored.  The vbar is switched to point to `vbar0` in preparation to
   handle further exceptions.  Finally a branch to the runtime vector
   table entry is taken to complete the handling of the original
   exception.

This workaround is enabled by default on the affected CPUs.

NOTE
====

There are 4 different stubs in Secure-EL1.  Each stub corresponds to
an exception type such as Sync/IRQ/FIQ/SError.  Each stub will move a
different value in `R0` before doing an SMC call back into EL3.
Without this piece of information it would not be possible to know
what the original exception type was as we cannot use `ESR_EL3` to
distinguish between IRQs and FIQs.

Change-Id: I90b32d14a3735290b48685d43c70c99daaa4b434
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

This patch adds a new build option, ENABLE_SVE_FOR_NS, which when set
to one EL3 will check to see if the Scalable Vector Extension (SVE) is
implemented when entering and exiting the Non-secure world.

If SVE is implemented, EL3 will do the following:

- Entry to Non-secure world: SIMD, FP and SVE functionality is enabled.

- Exit from Non-secure world: SIMD, FP and SVE functionality is
  disabled. As SIMD and FP registers are part of the SVE Z-registers
  then any use of SIMD / FP functionality would corrupt the SVE
  registers.

The build option default is 1. The SVE functionality is only supported
on AArch64 and so the build option is set to zero when the target
archiecture is AArch32.

This build option is not compatible with the CTX_INCLUDE_FPREGS - an
assert will be raised on platforms where SVE is implemented and both
ENABLE_SVE_FOR_NS and CTX_INCLUDE_FPREGS are set to 1.

Also note this change prevents secure world use of FP&SIMD registers on
SVE-enabled platforms. Existing Secure-EL1 Payloads will not work on
such platforms unless ENABLE_SVE_FOR_NS is set to 0.

Additionally, on the first entry into the Non-secure world the SVE
functionality is enabled and the SVE Z-register length is set to the
maximum size allowed by the architecture. This includes the use case
where EL2 is implemented but not used.

Change-Id: Ie2d733ddaba0b9bef1d7c9765503155188fe7dae
Signed-off-by: David Cunado <david.cunado@arm.com>

The `ENABLE_AMU` build option can be used to enable the
architecturally defined AMU counters.  At present, there is no support
for the auxiliary counter group.

Change-Id: I7ea0c0a00327f463199d1b0a481f01dadb09d312
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Factor out SPE operations in a separate file.  Use the publish
subscribe framework to drain the SPE buffers before entering secure
world.  Additionally, enable SPE before entering normal world.

A side effect of this change is that the profiling buffers are now
only drained when a transition from normal world to secure world
happens.  Previously they were drained also on return from secure
world, which is unnecessary as SPE is not supported in S-EL1.

Change-Id: I17582c689b4b525770dbb6db098b3a0b5777b70a
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@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>

Provide a strong definition for plat_sdei_validate_sdei_entrypoint()
which translates client address to Physical Address, and then validating
the address to be present in DRAM.

Change-Id: Ib93eb66b413d638aa5524d1b3de36aa16d38ea11
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

A Secure Partition is a software execution environment instantiated in
S-EL0 that can be used to implement simple management and security
services. Since S-EL0 is an unprivileged exception level, a Secure
Partition relies on privileged firmware e.g. ARM Trusted Firmware to be
granted access to system and processor resources. Essentially, it is a
software sandbox that runs under the control of privileged software in
the Secure World and accesses the following system resources:

- Memory and device regions in the system address map.
- PE system registers.
- A range of asynchronous exceptions e.g. interrupts.
- A range of synchronous exceptions e.g. SMC function identifiers.

A Secure Partition enables privileged firmware to implement only the
absolutely essential secure services in EL3 and instantiate the rest in
a partition. Since the partition executes in S-EL0, its implementation
cannot be overly complex.

The component in ARM Trusted Firmware responsible for managing a Secure
Partition is called the Secure Partition Manager (SPM). The SPM is
responsible for the following:

- Validating and allocating resources requested by a Secure Partition.
- Implementing a well defined interface that is used for initialising a
  Secure Partition.
- Implementing a well defined interface that is used by the normal world
  and other secure services for accessing the services exported by a
  Secure Partition.
- Implementing a well defined interface that is used by a Secure
  Partition to fulfil service requests.
- Instantiating the software execution environment required by a Secure
  Partition to fulfil a service request.

Change-Id: I6f7862d6bba8732db5b73f54e789d717a35e802f
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Achin Gupta <achin.gupta@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The implementation is the same as those used to disable it in EL3.

Change-Id: Ibfe7e69034a691fbf57477c5a76a8cdca28f6b26
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

API documentation updated.

Change-Id: I40feec1fe67a960d035061b54dd55610bc34ce1d
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

API documentation updated.

Change-Id: I129725059299af6cc612bafa8d74817f779d7c4f
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Document the API in separate platform interrupt controller API document.

Change-Id: If18f208e10a8a243f5c59d226fcf48e985941949
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

The macro DEFINE_SYSREG_WRITE_CONST_FUNC defines an inline function
to an assembly statement that uses the MSR (immediate) instruction
to access the PSTATE.  The "i" (immediate) assembly constraint on
the operand was only satisfied when compiling with optimizations
enabled which resulted in the function being optimized out - the
"const uint64_t v" parameter was optimized out and replaced by a
literal value.

When compiling without optimizations, the function call remained and
therefore the parameter is not optimized out - compilation fails as
the constraint is impossible to satisfy by the compiler.

This patch replaces the function encapsulating the use of
the MSR (immediate) with a macro that allows the literal value to be
directly fed to the inline assembly statement

Change-Id: Ib379a7acc48ef3cb83090a680cd8a6ce1a94a9d9
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Currently TF does not initialise the PMCR_EL0 register in
the secure context or save/restore the register.

In particular, the DP field may not be set to one to prohibit
cycle counting in the secure state, even though event counting
generally is prohibited via the default setting of MDCR_EL3.SMPE
to 0.

This patch initialises PMCR_EL0.DP to one in the secure state
to prohibit cycle counting and also initialises other fields
that have an architectually UNKNOWN reset value.

Additionally, PMCR_EL0 is added to the list of registers that are
saved and restored during a world switch.

Similar changes are made for PMCR for the AArch32 execution state.

NOTE: secure world code at lower ELs that assume other values in PMCR_EL0
will be impacted.

Change-Id: Iae40e8c0a196d74053accf97063ebc257b4d2f3a
Signed-off-by: David Cunado <david.cunado@arm.com>

The type `unsigned long` is 32 bit wide in AArch32, but 64 bit wide in
AArch64. This is inconsistent and that's why we avoid using it as per
the Coding Guidelines. This patch changes all `UL` occurrences to `U`
or `ULL` depending on the context so that the size of the constant is
clear.

This problem affected the macro `BIT(nr)`. As long as this macro is used
to fill fields of registers, that's not a problem, since all registers
are 32 bit wide in AArch32 and 64 bit wide in AArch64. However, if the
macro is used to fill the fields of a 64-bit integer, it won't be able
to set the upper 32 bits in AArch32.

By changing the type of this macro to `unsigned long long` the behaviour
is always the same regardless of the architecture, as this type is
64-bit wide in both cases.

Some Tegra platform files have been modified by this patch.

Change-Id: I918264c03e7d691a931f0d1018df25a2796cc221
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>

This patch provides helper macros for both Device and Normal memory MAIR
encodings as defined by the ARM Architecture Reference Manual for ARMv8-A
(ARM DDI0487B.A).

Change-Id: I5faae7f2cf366390ad4ba1d9253c6f3b60fd5e20
Signed-off-by: David Cunado <david.cunado@arm.com>

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: Isla Mitchell <isla.mitchell@arm.com>

SPE is only supported in non-secure state.  Accesses to SPE specific
registers from SEL1 will trap to EL3.  During a world switch, before
`TTBR` is modified the SPE profiling buffers are drained.  This is to
avoid a potential invalid memory access in SEL1.

SPE is architecturally specified only for AArch64.

Change-Id: I04a96427d9f9d586c331913d815fdc726855f6b0
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This patch updates the el3_arch_init_common macro so that it fully
initialises essential control registers rather then relying on hardware
to set the reset values.

The context management functions are also updated to fully initialise
the appropriate control registers when initialising the non-secure and
secure context structures and when preparing to leave EL3 for a lower
EL.

This gives better alignement with the ARM ARM which states that software
must initialise RES0 and RES1 fields with 0 / 1.

This patch also corrects the following typos:

"NASCR definitions" -> "NSACR definitions"

Change-Id: Ia8940b8351dc27bc09e2138b011e249655041cfc
Signed-off-by: David Cunado <david.cunado@arm.com>

This patch uses the U() and ULL() macros for constants, to fix some
of the signed-ness defects flagged by the MISRA scanner.
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

In AArch64, privileged exception levels control the execution state
(a.k.a. register width) of the immediate lower Exception Level; i.e.
whether the lower exception level executes in AArch64 or AArch32 state.
For an exception level to have its execution state changed at run time,
it must request the change by raising a synchronous exception to the
higher exception level.

This patch implements and adds such a provision to the ARM SiP service,
by which an immediate lower exception level can request to switch its
execution state. The execution state is switched if the request is:

  - raised from non-secure world;

  - raised on the primary CPU, before any secondaries are brought online
    with CPU_ON PSCI call;

  - raised from an exception level immediately below EL3: EL2, if
    implemented; otherwise NS EL1.

If successful, the SMC doesn't return to the caller, but to the entry
point supplied with the call. Otherwise, the caller will observe the SMC
returning with STATE_SW_E_DENIED code. If ARM Trusted Firmware is built
for AArch32, the feature is not supported, and the call will always
fail.

For the ARM SiP service:

  - Add SMC function IDs for both AArch32 and AArch64;
  - Increment the SiP service minor version to 2;
  - Adjust the number of supported SiP service calls.

Add documentation for ARM SiP service.

Fixes ARM-software/tf-issues#436

Change-Id: I4347f2d6232e69fbfbe333b340fcd0caed0a4cea
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.

NOTE: Files that have been imported by FreeBSD have not been modified.

[0]: https://spdx.org/



Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

Replace all instances of checks with the new macro.

Change-Id: I0eec39b9376475a1a9707a3115de9d36f88f8a2a
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

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: Scott 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

Following steps are required to boot JUNO in AArch32 state:
1> BL1, in AArch64 state, loads BL2.
2> BL2, in AArch64 state, initializes DDR.
  Loads SP_MIN & BL33 (AArch32 executable)images.
  Calls RUN_IMAGE SMC to go back to BL1.
3> BL1 writes AArch32 executable opcodes, to load and branch
  at the entrypoint address of SP_MIN, at HI-VECTOR address and
  then request for warm reset in AArch32 state using RMR_EL3.

This patch makes following changes to facilitate above steps:
* Added assembly function to carry out step 3 above.
* Added region in TZC that enables Secure access to the
  HI-VECTOR(0xFFFF0000) address space.
* AArch32 image descriptor is used, in BL2, to load
  SP_MIN and BL33 AArch32 executable images.

A new flag `JUNO_AARCH32_EL3_RUNTIME` is introduced that
controls above changes. By default this flag is disabled.

NOTE: BL1 and BL2 are not supported in AArch32 state for JUNO.

Change-Id: I091d56a0e6d36663e6d9d2bb53c92c672195d1ec
Signed-off-by: Yatharth Kochar <yatharth.kochar@arm.com>
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This patch adds support for fake system suspend (SC7).
This is a debug mode, to ensure that a different code path is
executed for cases like pre-silicon development, where a
full-fledged SC7 is not possible in early stages.

This particular patch ensures that, if fake system suspend is
enabled (denoted by tegra_fake_system_suspend variable
having a non-zero value), instead of calling WFI, a request
for a warm reset is made for starting the SC7 exit procedure.

This ensures that the code path of kernel->ATF and back to
kernel is executed without depending on other components
involved in SC7 code path.

Additionally, this patch also adds support for SMC call
from kernel, enabling fake system suspend mode.
Signed-off-by: Vignesh Radhakrishnan <vigneshr@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

This patch modifies some of the functions in ARM platform layer to cater
for the case when multi-threading `MT` is set in MPIDR. A new build flag
`ARM_PLAT_MT` is added, and when enabled, the functions accessing MPIDR
now assume that the `MT` bit is set for the platform and access the bit
fields accordingly.

Also, a new API plat_arm_get_cpu_pe_count is added when `ARM_PLAT_MT` is
enabled, returning the PE count within the physical cpu corresponding to
`mpidr`.

Change-Id: I04ccf212ac3054a60882761f4087bae299af13cb
Signed-off-by: Summer Qin <summer.qin@arm.com>

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

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