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This options enables an implementation of SHA-256 that has a smaller
code footprint (~1.6 KB less) but is also ~30% slower. For ARM
platforms, code size is currently considered more important than
execution speed in the mbed TLS crypto module.

Added a small note about this option to the documentation of the
authentication framework.

Change-Id: I4c0b221ea5d3466465261316ba07b627fa01b233
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The commit abd2aba9

 introduced a
regression to the AArch32 sp_min Juno build. This patch fixes that.

Change-Id: I4b141717684d6aee60c761ea17f23170aa6708c3
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Add support for firmware upgrade on AArch32.
This patch has been tested on the FVP models.

NOTE: Firmware upgrade on Juno AArch32 is not currently supported.

Change-Id: I1ca8078214eaf86b46463edd14740120af930aec
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Co-Authored-By: Yatharth Kochar <yatharth.kochar@arm.com>

This patch adds `TRUSTED_BOARD_BOOT` support for AArch32 mode.

To build this patch the "mbedtls/include/mbedtls/bignum.h"
needs to be modified to remove `#define MBEDTLS_HAVE_UDBL`
when `MBEDTLS_HAVE_INT32` is defined. This is a workaround
for "https://github.com/ARMmbed/mbedtls/issues/708

"

NOTE: TBBR support on Juno AArch32 is not currently supported.

Change-Id: I86d80e30b9139adc4d9663f112801ece42deafcf
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Co-Authored-By: Yatharth Kochar <yatharth.kochar@arm.com>

A previous patch superseded the MBEDTLS_KEY_ALG. This patch updates
the ARM platforms to use the new TF_MBEDTLS_KEY_ALG define.

Change-Id: Ie0e1bc272e127e879ac58e7cfcbe268751d7688e
Signed-off-by: David Cunado <david.cunado@arm.com>

We used to have the following circular dependency in the FVP platform
header files:

 +-> arm_def.h ---> platform_def.h ---> fvp_def.h --+
 |__________________________________________________|

This patch breaks it by not including 'arm_def.h' from 'fvp_def.h'.

Change-Id: I280d906559e3343dd38764029e77c0ea768b4fec
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

A new file added as part of arm-trusted-firmware#927 was missing the
SPDX license identifier - this patch adds the missing identifier.

Change-Id: Id1355f2bdca930b7e65bb54eff7e6c764ebb0d96
Signed-off-by: David Cunado <david.cunado@arm.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

The CSS power management layer previously allowed to suspend system
power domain level via both PSCI CPU_SUSPEND and PSCI SYSTEM_SUSPEND
APIs. System suspend via PSCI CPU_SUSPEND was always problematic to
support because of issues with targeting wakeup interrupts to
suspended cores before the per-cpu GIC initialization is done. This
is not the case for PSCI SYSTEM_SUSPEND API because all the other
cores are expected to be offlined prior to issuing system suspend and
PSCI CPU_ON explicit calls will be made to power them on. Hence the Juno
platform used to downgrade the PSCI CPU_SUSPEND request for system
power domain level to cluster level by overriding the default
`plat_psci_pm_ops` exported by CSS layer.

Given the direction the new CSS platforms are evolving, it is best to
limit the system suspend only via PSCI SYSTEM_SUSPEND API for all
CSS platforms. This patch makes changes to allow system suspend
only via PSCI SYSTEM_SUSPEND API. The override of `plat_psci_ops`
for Juno is removed.

Change-Id: Idb30eaad04890dd46074e9e888caeedc50a4b533
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

This patch adds support for SP_MIN on JUNO platform.
The changes include addition of AArch32 assembly files,
JUNO specific SP_MIN make file and miscellaneous changes
in ARM platform files to enable support for SP_MIN.

Change-Id: Id1303f422fc9b98b9362c757b1a4225a16fffc0b
Signed-off-by: Yatharth Kochar <yatharth.kochar@arm.com>
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

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>

If there is a pending interrupt, it is possible for the AP to come out
of the final WFI before SCP has a chance to act on it.  Prevent this
by disabling the GIC CPU interface before issuing a WFI.

Previously, SCP would not wait on WFI before taking an action but
would shut down the core or system regardless.

Change-Id: Ib0bcf69a515d540ed4f73c11e40ec7c863e39c92
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

ARM platforms have migrated to the translation tables library v2.
However, for testing purposes, it can be useful to temporarily switch
back to the old version.

This patch introduces the option `ARM_XLAT_TABLES_LIB_V1`, that switches
to v1 of the library when is set to 1. By default, it is 0, so that ARM
platforms use the new version unless specifically stated.

Updated User Guide.

Change-Id: I53d3c8dd97706f6af9c6fca0364a88ef341efd31
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

If SCP_BL2 is passed in from the command line, it is recognized by
make_helpers/tbbr/tbbr_tools.mk, and the cert_create tool generates
the corresponding key and content certificates.

On the other hand, the top-level Makefile does not care SCP_BL2, so
the --scp-fw option is not passed to the fiptool.  As far as I see
plat/arm/css/common/css_common.mk, it looks like a platform's job to
add $(eval $(call FIP_ADD_IMG,SCP_BL2,--scp-fw)).

We can make the top-level Makefile kind enough to take care of it.
This is useful when we want to have optional SCP_BL2 firmware.

Adjust css_common.mk so that Juno still requires SCP_BL2 by default.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Some header files using the ULL() macro were not directly including
utils.h where the macro definition resides. As a consequence, a linker
script with values using this macro did not see the macro definition
and kept the "ULL(<value>)" call in the preprocessed file, which lead to
link error.

Files using ULL() macro now include utils.h directly.

Change-Id: I433a7f36bd21a156c20e69bc2a2bb406140ebdf9
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

Change-Id: I7f3e4bfd46613c6311ba4015d56705414fd6feab
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This function fills the buffer (first argument) with the specified
number of bytes (second argument) from the trusted entropy source.

This function will be used to initialize the stack protector canary.

Change-Id: Iff15aaf4778c13fa883ecb5528fcf9b8479d4489
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

Introduce new build option ENABLE_STACK_PROTECTOR. It enables
compilation of all BL images with one of the GCC -fstack-protector-*
options.

A new platform function plat_get_stack_protector_canary() is introduced.
It returns a value that is used to initialize the canary for stack
corruption detection. Returning a random value will prevent an attacker
from predicting the value and greatly increase the effectiveness of the
protection.

A message is printed at the ERROR level when a stack corruption is
detected.

To be effective, the global data must be stored at an address
lower than the base of the stacks. Failure to do so would allow an
attacker to overwrite the canary as part of an attack which would void
the protection.

FVP implementation of plat_get_stack_protector_canary is weak as
there is no real source of entropy on the FVP. It therefore relies on a
timer's value, which could be predictable.

Change-Id: Icaaee96392733b721fa7c86a81d03660d3c1bc06
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

This API makes sure that all the characters sent to the crash console
are output before returning from it.

Porting guide updated.

Change-Id: I1785f970a40f6aacfbe592b6a911b1f249bb2735
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Juno platform Makefile is responsible for enabling all the relevant
errata. As the Juno platform port does not know which revision of Juno
the TF
is compiled for, the revision of the cores are unknown and so all errata
up to this date are needed on at least one revision of Juno.

Change-Id: I38e1d6efc17e703f2bd55e0714f8d8fa4778f696
Signed-off-by: Douglas Raillard <douglas.raillard@arm.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>

These source file definitions should be defined in generic
Makefiles so that all platforms can benefit. Ensure that the
symbols are properly marked as weak so they can be overridden
by platforms.

NOTE: This change is a potential compatibility break for
non-upstream platforms.

Change-Id: I7b892efa9f2d6d216931360dc6c436e1d10cffed
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

ARM erratum 855873 applies to all Cortex-A53 CPUs.
The recommended workaround is to promote "data cache clean"
instructions to "data cache clean and invalidate" instructions.
For core revisions of r0p3 and later this can be done by setting a bit
in the CPUACTLR_EL1 register, so that hardware takes care of the promotion.
As CPUACTLR_EL1 is both IMPLEMENTATION DEFINED and can be trapped to EL3,
we set the bit in firmware.
Also we dump this register upon crashing to provide more debug
information.

Enable the workaround for the Juno boards.

Change-Id: I3840114291958a406574ab6c49b01a9d9847fec8
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

Modify ARM common makefile to use version 2 of the translation tables
library and include the new header in C files.

Simplify header dependencies related to this library to simplify the
change.

The following table contains information about the size increase in
bytes for BL1 after applying this patch. The code has been compiled for
different configurations of FVP in AArch64 mode with compiler GCC 4.9.3
20150413. The sizes have been calculated with the output of `nm` by
adding the size of all regions and comparing the total size before and
after the change. They are sumarized in the table below:

                               text   bss   data  total
        Release                +660   -20    +88   +728
        Debug                  +740   -20   +242   +962
        Debug (LOG_LEVEL=50)  +1120   -20   +317  +1417

Change-Id: I539e307f158ab71e3a8b771640001fc1bf431b29
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@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>

On Juno, the secure privileged invasive debug authentication signal
(SPIDEN) is controlled by board SCC registers, which by default enable
SPIDEN.  Disable secure privileged external debug in release builds by
programming the appropriate Juno SoC registers.

Change-Id: I61045f09a47dc647bbe95e1b7a60e768f5499f49
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This patch introduces the following three platform interfaces:

* void plat_psci_stat_accounting_start(const psci_power_state_t *state_info)

  This is an optional hook that platforms can implement in order
  to perform accounting before entering a low power state.  This
  typically involves capturing a timestamp.

* void plat_psci_stat_accounting_stop(const psci_power_state_t *state_info)

  This is an optional hook that platforms can implement in order
  to perform accounting after exiting from a low power state.  This
  typically involves capturing a timestamp.

* u_register_t plat_psci_stat_get_residency(unsigned int lvl,
	const psci_power_state_t *state_info,
	unsigned int last_cpu_index)

  This is an optional hook that platforms can implement in order
  to calculate the PSCI stat residency.

If any of these interfaces are overridden by the platform, it is
recommended that all of them are.

By default `ENABLE_PSCI_STAT` is disabled.  If `ENABLE_PSCI_STAT`
is set but `ENABLE_PMF` is not set then an alternative PSCI stat
collection backend must be provided.  If both are set, then default
weak definitions of these functions are provided, using PMF to
calculate the residency.

NOTE: Previously, platforms did not have to explicitly set
`ENABLE_PMF` since this was automatically done by the top-level
Makefile.

Change-Id: I17b47804dea68c77bc284df15ee1ccd66bc4b79b
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

Replace all use of memset by zeromem when zeroing moderately-sized
structure by applying the following transformation:
memset(x, 0, sizeof(x)) => zeromem(x, sizeof(x))

As the Trusted Firmware is compiled with -ffreestanding, it forbids the
compiler from using __builtin_memset and forces it to generate calls to
the slow memset implementation. Zeromem is a near drop in replacement
for this use case, with a more efficient implementation on both AArch32
and AArch64.

Change-Id: Ia7f3a90e888b96d056881be09f0b4d65b41aa79e
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

Introduce zeromem_dczva function on AArch64 that can handle unaligned
addresses and make use of DC ZVA instruction to zero a whole block at a
time. This zeroing takes place directly in the cache to speed it up
without doing external memory access.

Remove the zeromem16 function on AArch64 and replace it with an alias to
zeromem. This zeromem16 function is now deprecated.

Remove the 16-bytes alignment constraint on __BSS_START__ in
firmware-design.md as it is now not mandatory anymore (it used to comply
with zeromem16 requirements).

Change the 16-bytes alignment constraints in SP min's linker script to a
8-bytes alignment constraint as the AArch32 zeromem implementation is now
more efficient on 8-bytes aligned addresses.

Introduce zero_normalmem and zeromem helpers in platform agnostic header
that are implemented this way:
* AArch32:
	* zero_normalmem: zero using usual data access
	* zeromem: alias for zero_normalmem
* AArch64:
	* zero_normalmem: zero normal memory  using DC ZVA instruction
	                  (needs MMU enabled)
	* zeromem: zero using usual data access

Usage guidelines: in most cases, zero_normalmem should be preferred.

There are 2 scenarios where zeromem (or memset) must be used instead:
* Code that must run with MMU disabled (which means all memory is
  considered device memory for data accesses).
* Code that fills device memory with null bytes.

Optionally, the following rule can be applied if performance is
important:
* Code zeroing small areas (few bytes) that are not secrets should use
  memset to take advantage of compiler optimizations.

  Note: Code zeroing security-related critical information should use
  zero_normalmem/zeromem instead of memset to avoid removal by
  compilers' optimizations in some cases or misbehaving versions of GCC.

Fixes ARM-software/tf-issues#408

Change-Id: Iafd9663fc1070413c3e1904e54091cf60effaa82
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

With GCC 6.2 compiler, more C undefined behaviour is being flagged as
warnings, which result in build errors in ARM TF build.

The specific issue that this patch resolves is the use of (1 << 31),
which is predominantly used in case statements, where 1 is represented
as a signed int. When shifted to msb the behaviour is undefined.

The resolution is to specify 1 as an unsigned int using a convenience
macro ULL(). A duplicate macro MAKE_ULL() is replaced.

Fixes ARM-software/tf-issues#438

Change-Id: I08e3053bbcf4c022ee2be33a75bd0056da4073e1
Signed-off-by: David Cunado <david.cunado@arm.com>

One nasty part of ATF is some of boolean macros are always defined
as 1 or 0, and the rest of them are only defined under certain
conditions.

For the former group, "#if FOO" or "#if !FOO" must be used because
"#ifdef FOO" is always true.  (Options passed by $(call add_define,)
are the cases.)

For the latter, "#ifdef FOO" or "#ifndef FOO" should be used because
checking the value of an undefined macro is strange.

For AARCH32/AARCH64, these macros are defined in the top-level
Makefile as follows:

ifeq (${ARCH},aarch32)
        $(eval $(call add_define,AARCH32))
else
        $(eval $(call add_define,AARCH64))
endif

This means only one of the two is defined.  So, AARCH32/AARCH64
belongs to the latter group where we should use #ifdef or #ifndef.
The conditionals are mostly coded correctly, but I see some mistakes.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

One nasty part of ATF is some of boolean macros are always defined
as 1 or 0, and the rest of them are only defined under certain
conditions.

For the former group, "#if FOO" or "#if !FOO" must be used because
"#ifdef FOO" is always true.  (Options passed by $(call add_define,)
are the cases.)

For the latter, "#ifdef FOO" or "#ifndef FOO" should be used because
checking the value of an undefined macro is strange.

Here, IMAGE_BL* is handled by make_helpers/build_macro.mk like
follows:

  $(eval IMAGE := IMAGE_BL$(call uppercase,$(3)))

  $(OBJ): $(2)
          @echo "  CC      $$<"
          $$(Q)$$(CC) $$(TF_CFLAGS) $$(CFLAGS) -D$(IMAGE) -c $$< -o $$@

This means, IMAGE_BL* is defined when building the corresponding
image, but *undefined* for the other images.

So, IMAGE_BL* belongs to the latter group where we should use #ifdef
or #ifndef.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

We have lots of duplicated defines (and comment blocks too).
Move them to include/plat/common/common_def.h.

While we are here, suffix the end address with _END instead of
_LIMIT.  The _END is a better fit to indicate the linker-derived
real end address.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The usage of _LIMIT seems odd here, so rename as follows:
  BL_CODE_LIMIT     --> BL_CODE_END
  BL_RO_DATA_LIMIT  --> BL_RO_DATA_END
  BL1_CODE_LIMIT    --> BL1_CODE_END
  BL1_RO_DATA_LIMIT --> BL1_RO_DATA_END

Basically, we want to use _LIMIT and _END properly as follows:
  *_SIZE + *_MAX_SIZE = *_LIMIT
  *_SIZE + *_SIZE     = *_END

The _LIMIT is generally defined by platform_def.h to indicate the
platform-dependent memory constraint.  So, its typical usage is
  ASSERT(. <= BL31_LIMIT, "BL31 image has exceeded its limit.")
in a linker script.

On the other hand, _END is used to indicate the end address of the
compiled image, i.e. we do not know it until the image is linked.

Here, all of these macros belong to the latter, so should be
suffixed with _END.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Before adding a base address and a size to compute the end
address of an image to copy or authenticate, check this
won't result in an integer overflow. If it does then consider
the input arguments are invalid.

As a result, bl1_plat_mem_check() can now safely assume the
end address (computed as the sum of the base address and size
of the memory region) doesn't overflow, as the validation is
done upfront in bl1_fwu_image_copy/auth(). A debug assertion
has been added nonetheless in the ARM implementation in order
to help catching such problems, should bl1_plat_mem_check()
be called in a different context in the future.

Fixes TFV-1: Malformed Firmware Update SMC can result in copy
of unexpectedly large data into secure memory

Change-Id: I8b8f8dd4c8777705722c7bd0e8b57addcba07e25
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Signed-off-by: Dan Handley <dan.handley@arm.com>

ASM_ASSERT failure and panic messages are suppressed at present. This
patch enables printing the PC location for panic messages, and file name
and line number upon assembly assert failure.

Change-Id: I80cb715988e7ce766f64da1e1d7065a74a096a0c
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

The previous code required that a certificate be signed with the ROT
key before the platform's NV counter could be updated with the value
in the certificate.  This implies that the Non-Trusted NV counter was
not being updated for Non-Trusted content certificates, as they cannot
be signed with the ROT key in the TBBR CoT scheme.

The code is reworked to only allow updating the platform's Trusted NV
counter when a certificate protected by the Trusted NV counter is
signed with the ROT key.

Content certificates protected by the Non-Trusted NV counter are
allowed to update the platform's Non-Trusted NV counter, assuming
that the certificate value is higher than the platform's value.

A new optional platform API has been introduced, named
plat_set_nv_ctr2().  Platforms may choose to implement it and perform
additional checks based on the authentication image descriptor before
modifying the NV counters.  A default weak implementation is available
that just calls into plat_set_nv_ctr().

Fixes ARM-software/tf-issues#426

Change-Id: I4fc978fd28a3007bc0cef972ff1f69ad0413b79c
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>