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This patch adds support for non-volatile counter authentication to
the Authentication Module. This method consists of matching the
counter values provided in the certificates with the ones stored
in the platform. If the value from the certificate is lower than
the platform, the boot process is aborted. This mechanism protects
the system against rollback.

The TBBR CoT has been updated to include this method as part of the
authentication process. Two counters are used: one for the trusted
world images and another for the non trusted world images.

** NEW PLATFORM APIs (mandatory when TBB is enabled) **

int plat_get_nv_ctr(void *cookie, unsigned int *nv_ctr);

    This API returns the non-volatile counter value stored
    in the platform. The cookie in the first argument may be
    used to select the counter in case the platform provides
    more than one (i.e. TBSA compliant platforms must provide
    trusted and non-trusted counters). This cookie is specified
    in the CoT.

int plat_set_nv_ctr(void *cookie, unsigned int nv_ctr);

    This API sets a new counter value. The cookie may be
    used to select the counter to be updated.

An implementation of these new APIs for ARM platforms is also
provided. The values are obtained from the Trusted Non-Volatile
Counters peripheral. The cookie is used to pass the extension OID.
This OID may be interpreted by the platform to know which counter
must return. On Juno, The trusted and non-trusted counter values
have been tied to 31 and 223, respectively, and cannot be modified.

** IMPORTANT **

THIS PATCH BREAKS THE BUILD WHEN TRUSTED_BOARD_BOOT IS ENABLED. THE
NEW PLATFORM APIs INTRODUCED IN THIS PATCH MUST BE IMPLEMENTED IN
ORDER TO SUCCESSFULLY BUILD TF.

Change-Id: Ic943b76b25f2a37f490eaaab6d87b4a8b3cbc89a

Added a new platform porting function plat_panic_handler, to allow
platforms to handle unexpected error situations. It must be
implemented in assembly as it may be called before the C environment
is initialized. A default implementation is provided, which simply
spins.

Corrected all dead loops in generic code to call this function
instead. This includes the dead loop that occurs at the end of the
call to panic().

All unnecesary wfis from bl32/tsp/aarch64/tsp_exceptions.S have
been removed.

Change-Id: I67cb85f6112fa8e77bd62f5718efcef4173d8134

The previous reset code in BL1 performed the following steps in
order:

1. Warm/Cold boot detection.
   If it's a warm boot, jump to warm boot entrypoint.

2. Primary/Secondary CPU detection.
   If it's a secondary CPU, jump to plat_secondary_cold_boot_setup(),
   which doesn't return.

3. CPU initialisations (cache, TLB...).

4. Memory and C runtime initialization.

For a secondary CPU, steps 3 and 4 are never reached. This shouldn't
be a problem in most cases, since current implementations of
plat_secondary_cold_boot_setup() either panic or power down the
secondary CPUs.

The main concern is the lack of secondary CPU initialization when
bare metal EL3 payloads are used in case they don't take care of this
initialisation themselves.

This patch moves the detection of primary/secondary CPU after step 3
so that the CPU initialisations are performed per-CPU, while the
memory and the C runtime initialisation are only performed on the
primary CPU. The diagrams used in the ARM Trusted Firmware Reset
Design documentation file have been updated to reflect the new boot
flow.

Platforms ports might be affected by this patch depending on the
behaviour of plat_secondary_cold_boot_setup(), as the state of the
platform when entering this function will be different.

Fixes ARM-software/tf-issues#342

Change-Id: Icbf4a0ee2a3e5b856030064472f9fa6696f2eb9e

This patch clarifies a porting API in the Porting Guide that do not
follow the ARM Architecture Program Calling Standards (AAPCS). The
list of registers that are allowed to be clobbered by this API has
been updated in the Porting Guide.

Fixes ARM-software/tf-issues#259

Change-Id: Ibf2adda2e1fb3e9b8f53d8a918d5998356eb8fce

`board_arm_def.h` contains multiple definitions of
`PLAT_ARM_MMAP_ENTRIES` and `MAX_XLAT_TABLES` that are optimised for
memory usage depending upon the chosen build configuration. To ease
maintenance of these constants, this patch replaces their multiple
definitions with a single set of definitions that will work on all ARM
platforms.

Platforms can override the defaults with optimal values by enabling the
`ARM_BOARD_OPTIMISE_MMAP` build option. An example has been provided in
the Juno ADP port.

Additionally, `PLAT_ARM_MMAP_ENTRIES` is increased by one to accomodate
future ARM platforms.

Change-Id: I5ba6490fdd1e118cc9cc2d988ad7e9c38492b6f0

The common topology description helper funtions and macros for
ARM Standard platforms assumed a dual cluster system. This is not
flexible enough to scale to multi cluster platforms. This patch does
the following changes for more flexibility in defining topology:

1. The `plat_get_power_domain_tree_desc()` definition is moved from
   `arm_topology.c` to platform specific files, that is `fvp_topology.c`
   and `juno_topology.c`. Similarly the common definition of the porting
   macro `PLATFORM_CORE_COUNT` in `arm_def.h` is moved to platform
   specific `platform_def.h` header.

2. The ARM common layer porting macros which were dual cluster specific
   are now removed and a new macro PLAT_ARM_CLUSTER_COUNT is introduced
   which must be defined by each ARM standard platform.

3. A new mandatory ARM common layer porting API
   `plat_arm_get_cluster_core_count()` is introduced to enable the common
   implementation of `arm_check_mpidr()` to validate MPIDR.

4. For the FVP platforms, a new build option `FVP_NUM_CLUSTERS` has been
   introduced which allows the user to specify the cluster count to be
   used to build the topology tree within Trusted Firmare. This enables
   Trusted Firmware to be built for multi cluster FVP models.

Change-Id: Ie7a2e38e5661fe2fdb2c8fdf5641d2b2614c2b6b

This patch adds a link to the Cortex-A57 Software Optimization Guide
in the ARM CPU Specific Build Macros document to justify the default
value of the A57_DISABLE_NON_TEMPORAL_HINT build flag.

Change-Id: I9779e42a4bb118442b2b64717ce143314ec9dd16

The folowing build options were missing from the User Guide and have been
documented:

 - CTX_INCLUDE_FPREGS
 - DISABLE_PEDANTIC
 - BUILD_STRING
 - VERSION_STRING
 - BUILD_MESSAGE_TIMESTAMP

Change-Id: I6a9c39ff52cad8ff04deff3ac197af84d437b8b7

Current code mandates loading of SCP_BL2/SCP_BL2U images for all
CSS platforms. On future ARM CSS platforms, the Application
Processor (AP) might not need to load these images. So, these
items can be removed from the FIP on those platforms.

BL2 tries to load  SCP_BL2/SCP_BL2U images if their base
addresses are defined causing boot error if the images are not
found in FIP.

This change adds a make flag `CSS_LOAD_SCP_IMAGES` which if set
to `1` does:
1. Adds SCP_BL2, SCP_BL2U images to FIP.
2. Defines the base addresses of these images so that AP loads
   them.

And vice-versa if it is set to `0`. The default value is set to
`1`.

Change-Id: I5abfe22d5dc1e9d80d7809acefc87b42a462204a

ARM PL061 GPIO driver requires the "PLAT_PL061_MAX_GPIOS" definition.
By default, it's defined to 32 in PL061 GPIO driver. If user wants
more PL061 controllers in platform, user should define the build
flag in platform.mk instead.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>

The LDNP/STNP instructions as implemented on Cortex-A53 and
Cortex-A57 do not behave in a way most programmers expect, and will
most probably result in a significant speed degradation to any code
that employs them. The ARMv8-A architecture (see Document ARM DDI
0487A.h, section D3.4.3) allows cores to ignore the non-temporal hint
and treat LDNP/STNP as LDP/STP instead.

This patch introduces 2 new build flags:
A53_DISABLE_NON_TEMPORAL_HINT and A57_DISABLE_NON_TEMPORAL_HINT
to enforce this behaviour on Cortex-A53 and Cortex-A57. They are
enabled by default.

The string printed in debug builds when a specific CPU errata
workaround is compiled in but skipped at runtime has been
generalised, so that it can be reused for the non-temporal hint use
case as well.

Change-Id: I3e354f4797fd5d3959872a678e160322b13867a1

Move up to Base FVP version 7.2 (build 0.8/7202) and Foundation FVP version
9.5 (build 9.5.41) in the user guide.

Change-Id: Ie9900596216808cadf45f042eec639d906e497b2

This patch adds a brief explanation of the top/bottom load approach
to the Firmware Design guide and how Trusted Firmware keeps track of
the free memory at boot time. This will help platform developers to
avoid unexpected results in the memory layout.

Fixes ARM-software/tf-issues#319

Change-Id: I04be7e24c1f3b54d28cac29701c24bf51a5c00ad

The memory translation library in Trusted Firmware supports
non-identity mappings for Physical to Virtual addresses since commit
f984ce84. However, the porting guide hasn't been updated
accordingly and still mandates the platform ports to use
identity-mapped page tables for all addresses.

This patch removes this out-dated information from the Porting Guide
and clarifies in which circumstances non-identity mapping may safely
be used.

Fixes ARM-software/tf-issues#258

Change-Id: I84dab9f3cabfc43794951b1828bfecb13049f706

This patch reworks the section about booting an EL3 payload in the
User Guide:

 - Centralize all EL3 payload related information in the same
   section.

 - Mention the possibility to program the EL3 payload in flash memory
   and execute it in place.

 - Provide model parameters for both the Base and Foundation FVPs.

 - Provide some guidance to boot an EL3 payload on Juno.

Change-Id: I975c8de6b9b54ff4de01a1154cba63271d709912

The PL011 TRM (ARM DDI 0183G) specifies that the UART must be
disabled before any of the control registers are programmed. The
PL011 driver included in TF does not disable the UART, so the
initialization in BL2 and BL31 is violating this requirement
(and potentially in BL1 if the UART is enabled after reset).

This patch modifies the initialization function in the PL011
console driver to disable the UART before programming the
control registers.

Register clobber list and documentation updated.

Fixes ARM-software/tf-issues#300

Change-Id: I839b2d681d48b03f821ac53663a6a78e8b30a1a1

Currently, Trusted Firmware on ARM platforms unlocks access to the
timer frame registers that will be used by the Non-Secure world. This
unlock operation should be done by the Non-Secure software itself,
instead of relying on secure firmware settings.

This patch adds a new ARM specific build option 'ARM_CONFIG_CNTACR'
to unlock access to the timer frame by setting the corresponding
bits in the CNTACR<N> register. The frame id <N> is defined by
'PLAT_ARM_NSTIMER_FRAME_ID'. Default value is true (unlock timer
access).

Documentation updated accordingly.

Fixes ARM-software/tf-issues#170

Change-Id: Id9d606efd781e43bc581868cd2e5f9c8905bdbf6

GIC v2 and v3 specification references in the porting guide
should refer to publically visible links, not ARM internal links.

Change-Id: Ib47c8adda6a03581f23bcaed72d71c08c7dd9fb1
Signed-off-by: Yuping Luo <yuping.luo@arm.com>

Since commit 804040d1, the Juno port has moved from per-CPU mailboxes
to a single shared one. This patch updates an out-dated reference to
the former per-CPU mailboxes mechanism in the Firmware Design.

Change-Id: I355b54156b1ace1b3df4c4416e1e8625211677fc

Migrate all direct usage of __attribute__ to usage of their
corresponding macros from cdefs.h.
e.g.:
 - __attribute__((unused)) -> __unused
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>

This patch adds a brief description of 'MAX_MMAP_REGIONS' and
'ADDR_SPACE_SIZE' to the Porting Guide. These fields must be defined
by the platform in order to use the translation table library.

Change-Id: Ida366458fe2bc01979091a014dc38da0fae5991e

Change-Id: I4fcdb8e813e0392c2cd3d0623698e8319b3b0593

This patch fixes a couple of issues in the "CPU specific operations
framework" section in the Firmware Design document.

 * Fix broken link to the CPU Specific Build Macros document.

 * Fix the path to the cortex_a53.S file.

 * Fix power levels terminology.

Change-Id: Ib610791eaba13dab2823b7699bb63534bcd1c8fb

The fip_create tool specifies images in the command line using the
ARM TF naming convention (--bl2, --bl31, etc), while the cert_create
tool uses the TBBR convention (--tb-fw, --soc-fw, etc). This double
convention is confusing and should be aligned.

This patch updates the fip_create command line options to follow the
TBBR naming convention. Usage examples in the User Guide have been
also updated.

NOTE: users that build the FIP by calling the fip_create tool directly
from the command line must update the command line options in their
scripts. Users that build the FIP by invoking the main ARM TF Makefile
should not notice any difference.

Change-Id: I84d602630a2585e558d927b50dfde4dd2112496f

Change-Id: I23a852fc7d91f91923bb84bc3167a830d1bb7463

Change-Id: I6f49bd779f2a4d577c6443dd160290656cdbc59b

Remove the following redundant sentence from the user guide, which
implies the user should use the TF version from the Linaro release,
which was not the intention:

"However, the rest of this document assumes that you got the
Trusted Firmware as part of the Linaro release."

Also, tidied up the grammar in this section.

Change-Id: I5dae0b68d3683e2a85a7b3c6a31222182a66f6c8

This patch adds design documentation for the Firmware Update (FWU)
feature in `firmware-update.md`. It provides an overview of FWU,
describes the BL1 SMC interface, and includes diagrams showing
an example FWU boot flow and the FWU state machine.

This patch also updates the existing TF documents where needed:

*   `porting-guide.md`
*   `user-guide.md`
*   `firmware-design.md`
*   `rt-svc-writers-guide.md`
*   `trusted_board_boot.md`

Change-Id: Ie6de31544429b18f01327bd763175e218299a4ce
Co-Authored-By: Dan Handley <dan.handley@arm.com>

`FVP_TSP_RAM_LOCATION` has been renamed into `ARM_TSP_RAM_LOCATION`.

This patch introduces a new document presenting the ARM Trusted
Firmware Reset Design. It shows the reset code flow, lists the
different build options that affect it, in which case to use them
and what their exact effect is.

The section about using BL31 entrypoint as the reset address has
been moved from the general firmware design document to this one.
It's also been improved to explain why the FVP port supports the
RESET_TO_BL31 configuration, even though the reset vector address
can't be programmed dynamically.

This document includes some images, which have been generated using
Dia version 0.97.2. This tool can be obtained from:
https://wiki.gnome.org/Apps/Dia/Download
This patch provides:
 - the image files describing the different reset flow diagrams;
 - the source '.dia' file;
 - a script automating the generation of the images from the '.dia'
   file.
Note that the 2 latter files are not actually needed for the document
and are provided for convenience only, in case the reset images need
to be modified.

Change-Id: Ib6302e8209d418a5b31c4e85e55fd9e83caf2ca2

This patch updates the relevant documentation in ARM Trusted Firmware
for the new GIC drivers. The user-guide.md and porting-guide.md have been
updated as follows:

*  The build option to compile Trusted Firmware with different GIC drivers
   for FVP has been explained in the user-guide.md.

*  The implementation details of interrupt management framework porting
   APIs for GICv3 have been added in porting-guide.md.

*  The Linaro tracking kernel release does not work OOB in GICv3 mode.
   The instructions for changing UEFI configuration in order to run with
   the new GICv3 driver in ARM TF have been added to user-guide.md.

The interrupt-framework-design.md has been updated as follows:

*  Describes support for registering and handling interrupts targeted to EL3
   e.g. Group 0 interrupts in GICv3.

*  Describes the build option `TSP_NS_INTR_ASYNC_PREEMPT` in detail.

*  Describes preemption of TSP in S-EL1 by non secure interrupts and
   also possibly by higher priority EL3 interrupts.

*  Describes the normal world sequence for issuing `standard` SMC calls.

*  Modifies the document to correspond to the current state of interrupt
   handling in TSPD and TSP.

*  Modifies the various functions names in the document to reflect
   the current names used in code.

Change-Id: I78c9514b5be834f193405aad3c1752a4a9e27a6c

This patch removes the dash character from the image name, to
follow the image terminology in the Trusted Firmware Wiki page:

    https://github.com/ARM-software/arm-trusted-firmware/wiki

Changes apply to output messages, comments and documentation.

non-ARM platform files have been left unmodified.

Change-Id: Ic2a99be4ed929d52afbeb27ac765ceffce46ed76

This patch replaces all references to the SCP Firmware (BL0, BL30,
BL3-0, bl30) with the image terminology detailed in the TF wiki
(https://github.com/ARM-software/arm-trusted-firmware/wiki):

    BL0          -->  SCP_BL1
    BL30, BL3-0  -->  SCP_BL2
    bl30         -->  scp_bl2

This change affects code, documentation, build system, tools and
platform ports that load SCP firmware. ARM plaforms have been
updated to the new porting API.

IMPORTANT: build option to specify the SCP FW image has changed:

    BL30 --> SCP_BL2

IMPORTANT: This patch breaks compatibility for platforms that use BL2
to load SCP firmware. Affected platforms must be updated as follows:

    BL30_IMAGE_ID --> SCP_BL2_IMAGE_ID
    BL30_BASE --> SCP_BL2_BASE
    bl2_plat_get_bl30_meminfo() --> bl2_plat_get_scp_bl2_meminfo()
    bl2_plat_handle_bl30() --> bl2_plat_handle_scp_bl2()

Change-Id: I24c4c1a4f0e4b9f17c9e4929da815c4069549e58

This patch applies the TBBR naming convention to the certificates
and the corresponding extensions defined by the CoT:

    * Certificate UUID names
    * Certificate identifier names
    * OID names

Changes apply to:

    * Generic code (variables and defines)
    * The default certificate identifiers provided in the generic
      code
    * Build system
    * ARM platforms port
    * cert_create tool internal definitions
    * fip_create and cert_create tools command line options
    * Documentation

IMPORTANT: this change breaks the compatibility with platforms
that use TBBR. The platform will need to adapt the identifiers
and OIDs to the TBBR naming convention introduced by this patch:

Certificate UUIDs:

    UUID_TRUSTED_BOOT_FIRMWARE_BL2_CERT --> UUID_TRUSTED_BOOT_FW_CERT
    UUID_SCP_FIRMWARE_BL30_KEY_CERT --> UUID_SCP_FW_KEY_CERT
    UUID_SCP_FIRMWARE_BL30_CERT --> UUID_SCP_FW_CONTENT_CERT
    UUID_EL3_RUNTIME_FIRMWARE_BL31_KEY_CERT --> UUID_SOC_FW_KEY_CERT
    UUID_EL3_RUNTIME_FIRMWARE_BL31_CERT --> UUID_SOC_FW_CONTENT_CERT
    UUID_SECURE_PAYLOAD_BL32_KEY_CERT --> UUID_TRUSTED_OS_FW_KEY_CERT
    UUID_SECURE_PAYLOAD_BL32_CERT --> UUID_TRUSTED_OS_FW_CONTENT_CERT
    UUID_NON_TRUSTED_FIRMWARE_BL33_KEY_CERT --> UUID_NON_TRUSTED_FW_KEY_CERT
    UUID_NON_TRUSTED_FIRMWARE_BL33_CERT --> UUID_NON_TRUSTED_FW_CONTENT_CERT

Certificate identifiers:

    BL2_CERT_ID --> TRUSTED_BOOT_FW_CERT_ID
    BL30_KEY_CERT_ID --> SCP_FW_KEY_CERT_ID
    BL30_CERT_ID --> SCP_FW_CONTENT_CERT_ID
    BL31_KEY_CERT_ID --> SOC_FW_KEY_CERT_ID
    BL31_CERT_ID --> SOC_FW_CONTENT_CERT_ID
    BL32_KEY_CERT_ID --> TRUSTED_OS_FW_KEY_CERT_ID
    BL32_CERT_ID --> TRUSTED_OS_FW_CONTENT_CERT_ID
    BL33_KEY_CERT_ID --> NON_TRUSTED_FW_KEY_CERT_ID
    BL33_CERT_ID --> NON_TRUSTED_FW_CONTENT_CERT_ID

OIDs:

    TZ_FW_NVCOUNTER_OID --> TRUSTED_FW_NVCOUNTER_OID
    NTZ_FW_NVCOUNTER_OID --> NON_TRUSTED_FW_NVCOUNTER_OID
    BL2_HASH_OID --> TRUSTED_BOOT_FW_HASH_OID
    TZ_WORLD_PK_OID --> TRUSTED_WORLD_PK_OID
    NTZ_WORLD_PK_OID --> NON_TRUSTED_WORLD_PK_OID
    BL30_CONTENT_CERT_PK_OID --> SCP_FW_CONTENT_CERT_PK_OID
    BL30_HASH_OID --> SCP_FW_HASH_OID
    BL31_CONTENT_CERT_PK_OID --> SOC_FW_CONTENT_CERT_PK_OID
    BL31_HASH_OID --> SOC_AP_FW_HASH_OID
    BL32_CONTENT_CERT_PK_OID --> TRUSTED_OS_FW_CONTENT_CERT_PK_OID
    BL32_HASH_OID --> TRUSTED_OS_FW_HASH_OID
    BL33_CONTENT_CERT_PK_OID --> NON_TRUSTED_FW_CONTENT_CERT_PK_OID
    BL33_HASH_OID --> NON_TRUSTED_WORLD_BOOTLOADER_HASH_OID
    BL2U_HASH_OID --> AP_FWU_CFG_HASH_OID
    SCP_BL2U_HASH_OID --> SCP_FWU_CFG_HASH_OID
    NS_BL2U_HASH_OID --> FWU_HASH_OID

Change-Id: I1e047ae046299ca913911c39ac3a6e123bd41079

The mbed TLS library has introduced some changes in the API from
the 1.3.x to the 2.x releases. Using the 2.x releases requires
some changes to the crypto and transport modules.

This patch updates both modules to the mbed TLS 2.x API.

All references to the mbed TLS library in the code or documentation
have been updated to 'mbed TLS'. Old references to PolarSSL have
been updated to 'mbed TLS'.

User guide updated to use mbed TLS 2.2.0.

NOTE: moving up to mbed TLS 2.x from 1.3.x is not backward compatible.
Applying this patch will require an mbed TLS 2.x release to be used.
Also note that the mbed TLS license changed to Apache version 2.0.

Change-Id: Iba4584408653cf153091f2ca2ee23bc9add7fda4

Move up the version numbers in the user guide of:

 * DS-5 (to v5.22)
 * Base FVP (to 7.0)
 * Foundation FVP (to 9.4)
 * Linaro release (to 15.10)

Note that, starting from Linaro release 15.10, the related release
instructions have migrated from http://releases.linaro.org to the
ARM Connected Community website. The URLs in the User Guide have
been updated accordingly.

The 'libssl-dev' package has been removed from the list of
prerequisite tools, as it is already referenced on the ARM Connected
Community page. Also, the 'device-tree-compiler' package has been
marked as an optional dependency, since the Trusted Firmware
repository provides the prebuilt DTB files. Hence, this tool is
needed only when the user wants to rebuild the DTS files.

Change-Id: I4a172ece60bf90437131c6b96e73a9f1e9b40117

The Server Base System Architecture document (ARM-DEN-0029)
specifies a generic UART device. The programmer's view of this
generic UART is a subset of the ARM PL011 UART. However, the
current PL011 driver in Trusted Firmware uses some features
that are outside the generic UART specification.

This patch modifies the PL011 driver to exclude features outside
the SBSA generic UART specification by setting the boolean build
option 'PL011_GENERIC_UART=1'. Default value is 0 (use full
PL011 features).

User guide updated.

Fixes ARM-software/tf-issues#216

Change-Id: I6e0eb86f9d69569bc3980fb57e70d6da5d91a737

This patch overrides the default weak definition of
`bl31_plat_runtime_setup()` for ARM Standard platforms to
specify a BL31 runtime console. ARM Standard platforms are
now expected to define `PLAT_ARM_BL31_RUN_UART_BASE` and
`PLAT_ARM_BL31_RUN_UART_CLK_IN_HZ` macros which is required
by `arm_bl31_plat_runtime_setup()` to initialize the runtime
console.

The system suspend resume helper `arm_system_pwr_domain_resume()`
is fixed to initialize the runtime console rather than the boot
console on resumption from system suspend.

Fixes ARM-software/tf-issues#220

Change-Id: I80eafe5b6adcfc7f1fdf8b99659aca1c64d96975

It is not ideal for BL31 to continue to use boot console at
runtime which could be potentially uninitialized. This patch
introduces a new optional platform porting API
`bl31_plat_runtime_setup()` which allows the platform to perform
any BL31 runtime setup just prior to BL31 exit during cold boot.
The default weak implementation of this function will invoke
`console_uninit()` which will suppress any BL31 runtime logs.

On the ARM Standard platforms, there is an anomaly that
the boot console will be reinitialized on resumption from
system suspend in `arm_system_pwr_domain_resume()`. This
will be resolved in the following patch.

NOTE: The default weak definition of `bl31_plat_runtime_setup()`
disables the BL31 console. To print the BL31 runtime
messages, platforms must override this API and initialize a
runtime console.

Fixes ARM-software/tf-issues#328

Change-Id: Ibaf8346fcceb447fe1a5674094c9f8eb4c09ac4a