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ARM Trusted Firmware supports 2 different interconnect peripheral
drivers: CCI and CCN. ARM platforms are implemented using either of the
interconnect peripherals.

This patch adds a layer of abstraction to help ARM platform ports to
choose the right interconnect driver and corresponding platform support.
This is as described below:

1. A set of ARM common functions have been implemented to initialise an
interconnect and for entering/exiting a cluster from coherency. These
functions are prefixed as "plat_arm_interconnect_". Weak definitions of
these functions have been provided for each type of driver.

2.`plat_print_interconnect_regs` macro used for printing CCI registers is
moved from a common arm_macros.S to cci_macros.S.

3. The `ARM_CONFIG_HAS_CCI` flag used in `arm_config_flags` structure
is renamed to `ARM_CONFIG_HAS_INTERCONNECT`.

Change-Id: I02f31184fbf79b784175892d5ce1161b65a0066c

Prior to this patch, it was assumed that on all ARM platforms the bare
minimal security setup required is to program TrustZone protection. This
would always be done by programming the TZC-400 which was assumed to be
present in all ARM platforms. The weak definition of
platform_arm_security_setup() in plat/arm/common/arm_security.c
reflected these assumptions.

In reality, each ARM platform either decides at runtime whether
TrustZone protection needs to be programmed (e.g. FVPs) or performs
some security setup in addition to programming TrustZone protection
(e.g. NIC setup on Juno). As a result, the weak definition of
plat_arm_security_setup() is always overridden.

When a platform needs to program TrustZone protection and implements the
TZC-400 peripheral, it uses the arm_tzc_setup() function to do so. It is
also possible to program TrustZone protection through other peripherals
that include a TrustZone controller e.g. DMC-500. The programmer's
interface is slightly different across these various peripherals.

In order to satisfy the above requirements, this patch makes the
following changes to the way security setup is done on ARM platforms.

1. arm_security.c retains the definition of arm_tzc_setup() and has been
   renamed to arm_tzc400.c. This is to reflect the reliance on the
   TZC-400 peripheral to perform TrustZone programming. The new file is
   not automatically included in all platform ports through
   arm_common.mk. Each platform must include it explicitly in a platform
   specific makefile if needed.

   This approach enables introduction of similar library code to program
   TrustZone protection using a different peripheral. This code would be
   used by the subset of ARM platforms that implement this peripheral.

2. Due to #1 above, existing platforms which implements the TZC-400 have been
   updated to include the necessary files for both BL2, BL2U and BL31
   images.

Change-Id: I513c58f7a19fff2e9e9c3b95721592095bcb2735

This patch moves the definition of some macros used only on
ARM platforms from common headers to platform specific headers.
It also forces all ARM standard platforms to have distinct
definitions (even if they are usually the same).
 1. `PLAT_ARM_TZC_BASE` and `PLAT_ARM_NSTIMER_FRAME_ID` have been
     moved from `css_def.h` to `platform_def.h`.
 2. `MHU_BASE` used in CSS platforms is moved from common css_def.h
    to platform specific header `platform_def.h` on Juno and
    renamed as `PLAT_ARM_MHU_BASE`.
 3. To cater for different sizes of BL images, new macros like
    `PLAT_ARM_MAX_BL31_SIZE` have been created for each BL image. All
    ARM platforms need to define them for each image.

Change-Id: I9255448bddfad734b387922aa9e68d2117338c3f

This patch enables the ARM Cortex-A72 support in BL1 and BL31 on FVP.
This allows the same TF binaries to run on a Cortex-A72 based FVP
without recompiling them.

Change-Id: I4eb6bbad9f0e5d8704613f7c685c3bd22b45cf47

This patch adds support for ARM Cortex-A35 processor in the CPU
specific framework, as described in the Cortex-A35 TRM (r0p0).

Change-Id: Ief930a0bdf6cd82f6cb1c3b106f591a71c883464

Change-Id: I6f49bd779f2a4d577c6443dd160290656cdbc59b

fvp_pwr_domain_on() used to program the CPUs mailbox. This changed
with commit 804040d1 but the comment documenting this code still
refers to the mailbox programming. This patch removes this out-dated
information.

Change-Id: Ibfe2a426bdda6e71f20c83a99cb223ceca9c559c

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 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

This patch adds support for Firmware update in BL2U for ARM
platforms such that TZC initialization is performed on all
ARM platforms and (optionally) transfer of SCP_BL2U image on
ARM CSS platforms.

BL2U specific functions are added to handle early_platform and
plat_arch setup. The MMU is configured to map in the BL2U
code/data area and other required memory.

Change-Id: I57863295a608cc06e6cbf078b7ce34cbd9733e4f

This patch adds Firmware Update support for ARM platforms.

New files arm_bl1_fwu.c and juno_bl1_setup.c were added to provide
platform specific Firmware update code.

BL1 now includes mmap entry for `ARM_MAP_NS_DRAM1` to map DRAM for
authenticating NS_BL2U image(For both FVP and JUNO platform).

Change-Id: Ie116cd83f5dc00aa53d904c2f1beb23d58926555

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

Suport for ARM GIC v2.0 and v3.0 drivers has been reworked to create three
separate drivers instead of providing a single driver that can work on both
versions of the GIC architecture. These drivers correspond to the following
software use cases:

1. A GICv2 only driver that can run only on ARM GIC v2.0 implementations
   e.g. GIC-400

2. A GICv3 only driver that can run only on ARM GIC v3.0 implementations
   e.g. GIC-500 in a mode where all interrupt regimes use GICv3 features

3. A deprecated GICv3 driver that operates in legacy mode. This driver can
   operate only in the GICv2 mode in the secure world. On a GICv3 system, this
   driver allows normal world to run in either GICv3 mode (asymmetric mode)
   or in the GICv2 mode. Both modes of operation are deprecated on GICv3
   systems.

ARM platforms implement both versions of the GIC architecture. This patch adds a
layer of abstraction to help ARM platform ports chose the right GIC driver and
corresponding platform support. This is as described below:

1. A set of ARM common functions have been introduced to initialise the GIC and
   the driver during cold and warm boot. These functions are prefixed as
   "plat_arm_gic_". Weak definitions of these functions have been provided for
   each type of driver.

2. Each platform includes the sources that implement the right functions
   directly into the its makefile. The FVP can be instantiated with different
   versions of the GIC architecture. It uses the FVP_USE_GIC_DRIVER build option
   to specify which of the three drivers should be included in the build.

3. A list of secure interrupts has to be provided to initialise each of the
  three GIC drivers. For GIC v3.0 the interrupt ids have to be further
  categorised as Group 0 and Group 1 Secure interrupts. For GIC v2.0, the two
  types are merged and treated as Group 0 interrupts.

  The two lists of interrupts are exported from the platform_def.h. The lists
  are constructed by adding a list of board specific interrupt ids to a list of
  ids common to all ARM platforms and Compute sub-systems.

This patch also makes some fields of `arm_config` data structure in FVP redundant
and these unused fields are removed.

Change-Id: Ibc8c087be7a8a6b041b78c2c3bd0c648cd2035d8

This patch adds platform helpers for the new GICv2 and GICv3 drivers in
plat_gicv2.c and plat_gicv3.c. The platforms can include the appropriate
file in their build according to the GIC driver to be used. The existing
plat_gic.c is only meant for the legacy GIC driver.

In the case of ARM platforms, the major changes are as follows:

1. The crash reporting helper macro `arm_print_gic_regs` that prints the GIC CPU
   interface register values has been modified to detect the type of CPU
   interface being used (System register or memory mappped interface) before
   using the right interface to print the registers.

2. The power management helper function that is called after a core is powered
   up has been further refactored. This is to highlight that the per-cpu
   distributor interface should be initialised only when the core was originally
   powered down using the CPU_OFF PSCI API and not when the CPU_SUSPEND PSCI API
   was used.

3. In the case of CSS platforms, the system power domain restore helper
   `arm_system_pwr_domain_resume()` is now only invoked in the `suspend_finish`
   handler as the system power domain is always expected to be initialized when
   the `on_finish` handler is invoked.

Change-Id: I7fc27d61fc6c2a60cea2436b676c5737d0257df6

This patch fixes several issues with the SP804 delay timer on FVP:

* By default, the SP804 dual timer on FVP runs at 32 KHz. In order
  to run the timer at 35 MHz (as specified in the FVP user manual)
  the Overwrite bit in the SP810 control register must be set.

* The CLKMULT and CLKDIV definitions are mixed up:

      delta(us) = delta(ticks) * T(us) = delta(ticks) / f(MHz)

  From the delay function:

      delta_us = (delta * ops->clk_mult) / ops->clk_div;

  Matching both expressions:

      1 / f(MHz) = ops->clk_mult / ops->clk_div

  And consequently:

      f(MHz) = ops->clk_div / ops->clk_mult

  Which, for a 35 MHz timer, translates to:

      ops->clk_div = 35
      ops->clk_mult = 1

* The comment in the delay timer header file has been corrected:
  The ratio of the multiplier and the divider is the clock period
  in microseconds, not the frequency.

Change-Id: Iffd5ce0a5a28fa47c0720c0336d81b678ff8fdf1

This patch adds watchdog support on ARM platforms (FVP and Juno).
A secure instance of SP805 is used as Trusted Watchdog. It is
entirely managed in BL1, being enabled in the early platform setup
hook and disabled in the exit hook. By default, the watchdog is
enabled in every build (even when TBB is disabled).

A new ARM platform specific build option `ARM_DISABLE_TRUSTED_WDOG`
has been introduced to allow the user to disable the watchdog at
build time. This feature may be used for testing or debugging
purposes.

Specific error handlers for Juno and FVP are also provided in this
patch. These handlers will be called after an image load or
authentication error. On FVP, the Table of Contents (ToC) in the FIP
is erased. On Juno, the corresponding error code is stored in the
V2M Non-Volatile flags register. In both cases, the CPU spins until
a watchdog reset is generated after 256 seconds (as specified in
the TBBR document).

Change-Id: I9ca11dcb0fe15af5dbc5407ab3cf05add962f4b4

Normally, in the FVP port, secondary CPUs are immediately powered
down if they are powered on at reset. However, when booting an EL3
payload, we need to keep them powered on as the requirement is for
all CPUs to enter the EL3 payload image. This patch puts them in a
holding pen instead of powering them off.

Change-Id: I6526a88b907a0ddb820bead72f1d350a99b1692c

Patch 7e26fe1f deprecates IO specific return definitions in favour
of standard errno codes. This patch removes those definitions
and its usage from the IO framework, IO drivers and IO platform
layer. Following this patch, standard errno codes must be used
when checking the return value of an IO function.

Change-Id: Id6e0e9d0a7daf15a81ec598cf74de83d5768650f

This patch implements the necessary topology changes for supporting
system power domain on CSS platforms. The definition of PLAT_MAX_PWR_LVL and
PLAT_NUM_PWR_DOMAINS macros are removed from arm_def.h and are made platform
specific. In addition, the `arm_power_domain_tree_desc[]` and
`arm_pm_idle_states[]` are modified to support the system power domain
at level 2. With this patch, even though the power management operations
involving the system power domain will not return any error, the platform
layer will silently ignore any operations to the power domain. The actual
power management support for the system power domain will be added later.

Change-Id: I791867eded5156754fe898f9cdc6bba361e5a379

This patch does the following reorganization to psci power management (PM)
handler setup for ARM standard platform ports :

1. The mailbox programming required during `plat_setup_psci_ops()` is identical
   for all ARM platforms. Hence the implementation of this API is now moved
   to the common `arm_pm.c` file. Each ARM platform now must define the
   PLAT_ARM_TRUSTED_MAILBOX_BASE macro, which in current platforms is the same
   as ARM_SHARED_RAM_BASE.

2. The PSCI PM handler callback structure, `plat_psci_ops`, must now be
   exported via `plat_arm_psci_pm_ops`. This allows the common implementation
   of `plat_setup_psci_ops()` to return a platform specific `plat_psci_ops`.
   In the case of CSS platforms, a default weak implementation of the same is
   provided in `css_pm.c` which can be overridden by each CSS platform.

3. For CSS platforms, the PSCI PM handlers defined in `css_pm.c` are now
   made library functions and a new header file `css_pm.h` is added to export
   these generic PM handlers. This allows the platform to reuse the
   adequate CSS PM handlers and redefine others which need to be customized
   when overriding the default `plat_arm_psci_pm_ops` in `css_pm.c`.

Change-Id: I277910f609e023ee5d5ff0129a80ecfce4356ede

On Juno and FVP platforms, the Non-Secure System timer corresponds
to frame 1. However, this is a platform-specific decision and it
shouldn't be hard-coded. Hence, this patch introduces
PLAT_ARM_NSTIMER_FRAME_ID which should be used by all ARM platforms
to specify the correct non-secure timer frame.

Change-Id: I6c3a905d7d89200a2f58c20ce5d1e1d166832bba

This patch replaces the `ARM_TZC_BASE` constant with `PLAT_ARM_TZC_BASE` to
support different TrustZone Controller base addresses across ARM platforms.

Change-Id: Ie4e1c7600fd7a5875323c7cc35e067de0c6ef6dd

ARM TF configures all interrupts as non-secure except those which
are present in irq_sec_array. This patch updates the irq_sec_array
with the missing secure interrupts for ARM platforms.

It also updates the documentation to be inline with the latest
implementation.

Fixes ARM-software/tf-issues#312

Change-Id: I39956c56a319086e3929d1fa89030b4ec4b01fcc

This patch adds the necessary documentation updates to porting_guide.md
for the changes in the platform interface mandated as a result of the new
PSCI Topology and power state management frameworks. It also adds a
new document `platform-migration-guide.md` to aid the migration of existing
platform ports to the new API.

The patch fixes the implementation and callers of
plat_is_my_cpu_primary() to use w0 as the return parameter as implied by
the function signature rather than x0 which was used previously.

Change-Id: Ic11e73019188c8ba2bd64c47e1729ff5acdcdd5b

This patch implements the platform power managment handler to verify
non secure entrypoint for ARM platforms. The handler ensures that the
entry point specified by the normal world during CPU_SUSPEND, CPU_ON
or SYSTEM_SUSPEND PSCI API is a valid address within the non secure
DRAM.

Change-Id: I4795452df99f67a24682b22f0e0967175c1de429

Now that the FVP mailbox is no longer zeroed, the function
platform_mem_init() does nothing both on FVP and on Juno. Therefore,
this patch pools it as the default implementation on ARM platforms.

Change-Id: I007220f4531f15e8b602c3368a1129a5e3a38d91

Since there is a unique warm reset entry point, the FVP and Juno
port can use a single mailbox instead of maintaining one per core.
The mailbox gets programmed only once when plat_setup_psci_ops()
is invoked during PSCI initialization. This means mailbox is not
zeroed out during wakeup.

Change-Id: Ieba032a90b43650f970f197340ebb0ce5548d432

This patch adds support to the Juno and FVP ports for composite power states
with both the original and extended state-id power-state formats. Both the
platform ports use the recommended state-id encoding as specified in
Section 6.5 of the PSCI specification (ARM DEN 0022C). The platform build flag
ARM_RECOM_STATE_ID_ENC is used to include this support.

By default, to maintain backwards compatibility, the original power state
parameter format is used and the state-id field is expected to be zero.

Change-Id: Ie721b961957eaecaca5bf417a30952fe0627ef10

This patch migrates ARM reference platforms, Juno and FVP, to the new platform
API mandated by the new PSCI power domain topology and composite power state
frameworks. The platform specific makefiles now exports the build flag
ENABLE_PLAT_COMPAT=0 to disable the platform compatibility layer.

Change-Id: I3040ed7cce446fc66facaee9c67cb54a8cd7ca29

This patch extends the platform port by adding an API that returns
either the Root of Trust public key (ROTPK) or its hash. This is
usually stored in ROM or eFUSE memory. The ROTPK returned must be
encoded in DER format according to the following ASN.1 structure:

    SubjectPublicKeyInfo  ::=  SEQUENCE  {
        algorithm           AlgorithmIdentifier,
        subjectPublicKey    BIT STRING
    }

In case the platform returns a hash of the key:

    DigestInfo  ::= SEQUENCE {
        digestAlgorithm     AlgorithmIdentifier,
        keyDigest           OCTET STRING
    }

An implementation for ARM development platforms is provided in this
patch. When TBB is enabled, the ROTPK hash location must be specified
using the build option 'ARM_ROTPK_LOCATION'. Available options are:

    - 'regs' : return the ROTPK hash stored in the Trusted
      root-key storage registers.

    - 'devel_rsa' : return a ROTPK hash embedded in the BL1 and
      BL2 binaries. This hash has been obtained from the development
      RSA public key located in 'plat/arm/board/common/rotpk'.

On FVP, the number of MMU tables has been increased to map and
access the ROTPK registers.

A new file 'board_common.mk' has been added to improve code sharing
in the ARM develelopment platforms.

Change-Id: Ib25862e5507d1438da10773e62bd338da8f360bf

The Trusted firmware code identifies BL images by name. The platform
port defines a name for each image e.g. the IO framework uses this
mechanism in the platform function plat_get_image_source(). For
a given image name, it returns the handle to the image file which
involves comparing images names. In addition, if the image is
packaged in a FIP, a name comparison is required to find the UUID
for the image. This method is not optimal.

This patch changes the interface between the generic and platform
code with regard to identifying images. The platform port must now
allocate a unique number (ID) for every image. The generic code will
use the image ID instead of the name to access its attributes.

As a result, the plat_get_image_source() function now takes an image
ID as an input parameter. The organisation of data structures within
the IO framework has been rationalised to use an image ID as an index
into an array which contains attributes of the image such as UUID and
name. This prevents the name comparisons.

A new type 'io_uuid_spec_t' has been introduced in the IO framework
to specify images identified by UUID (i.e. when the image is contained
in a FIP file). There is no longer need to maintain a look-up table
[iname_name --> uuid] in the io_fip driver code.

Because image names are no longer mandatory in the platform port, the
debug messages in the generic code will show the image identifier
instead of the file name. The platforms that support semihosting to
load images (i.e. FVP) must provide the file names as definitions
private to the platform.

The ARM platform ports and documentation have been updated accordingly.
All ARM platforms reuse the image IDs defined in the platform common
code. These IDs will be used to access other attributes of an image in
subsequent patches.

IMPORTANT: applying this patch breaks compatibility for platforms that
use TF BL1 or BL2 images or the image loading code. The platform port
must be updated to match the new interface.

Change-Id: I9c1b04cb1a0684c6ee65dee66146dd6731751ea5

Add SP804 delay timer support to the FVP BSP.

This commit simply provides the 3 constants needed by the SP804
delay timer driver and calls sp804_timer_init() in
bl2_platform_setup(). The BSP does not currently use the delay
timer functions.

Note that the FVP SP804 is a normal world accessible peripheral
and should not be used by the secure world after transition
to the normal world.

Change-Id: I5f91d2ac9eb336fd81943b3bb388860dfb5f2b39
Co-authored-by: Dan Handley <dan.handley@arm.com>

This patch fixes the incorrect bit width used to extract the wakeup
reason from PSYSR in platform_get_entrypoint() function. This defect
did not have any observed regression.

Change-Id: I42652dbffc99f5bf50cc86a5878f28d730720d9a

On ARM standard platforms, snoop and DVM requests used to be enabled
for the primary CPU's cluster only in the first EL3 bootloader.
In other words, if the platform reset into BL1 then CCI coherency
would be enabled by BL1 only, and not by BL3-1 again.

However, this doesn't cater for platforms that use BL3-1 along with
a non-TF ROM bootloader that doesn't enable snoop and DVM requests.
In this case, CCI coherency is never enabled.

This patch modifies the function bl31_early_platform_setup() on
ARM standard platforms so that it always enables snoop and DVM
requests regardless of whether earlier bootloader stages have
already done it. There is no harm in executing this code twice.

ARM Trusted Firmware Design document updated accordingly.

Change-Id: Idf1bdeb24d2e1947adfbb76a509f10beef224e1c

Fix the return type of the FVP `plat_arm_topology_setup` function
to be `void` instead of `int` to match the declaration in
`plat_arm.h`.

This does not result in any change in behavior.

Change-Id: I62edfa7652b83bd26cffb7d167153959b38e37e7

Move the FVP port from plat/fvp to plat/arm/board/fvp. Also rename
some of the files so they are consistently prefixed with fvp_.
Update the platform makefiles accordingly.

Change-Id: I7569affc3127d66405f1548fc81b878a858e61b7