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This patch makes all the defines in the CPU libraries unique,
by prefixing them with the CPU name.

NOTE: PLATFORMS USING THESE MACROS WILL HAVE TO UPDATE THEIR CODE
TO START USING THE UPDATED NAMES
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

This patch adds the memory map region for the SCMI payload memory
and maps the Juno core indices to SCMI power domains via the
`plat_css_core_pos_to_scmi_dmn_id_map` array.

Change-Id: I0d2bb2a719ff5b6a9d8e22e91e1625ab14453665
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

The header tbbr_oid.h contains OIDs obtained by ARM Ltd.
so there is no good reason to use platform_oid.h
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Platforms aligned with TBBR are supposed to use their own OIDs, but
defining the same macros with different OIDs does not provide any
value (at least technically).

For easier use of TBBR, this commit allows platforms to reuse the OIDs
obtained by ARM Ltd.  This will be useful for non-ARM vendors that
do not need their own extension fields in their certificate files.

The OIDs of ARM Ltd. have been moved to include/tools_share/tbbr_oid.h

Platforms can include <tbbr_oid.h> instead of <platform_oid.h> by
defining USE_TBBR_DEFS as 1.  USE_TBBR_DEFS is 0 by default to keep the
backward compatibility.

For clarification, I inserted a blank line between headers from the
include/ directory (#include <...>) and ones from a local directory
(#include "..." ).
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.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>

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>

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>

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>

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>

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>

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>

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>

This patch enables TRUSTED_BOARD_BOOT (Authentication and FWU)
support, for AArch64, when LOAD_IMAGE_V2 is enabled.

This patch also enables LOAD_IMAGE_V2 for ARM platforms.

Change-Id: I294a2eebce7a30b6784c80c9d4ac7752808ee3ad
Signed-off-by: Yatharth Kochar <yatharth.kochar@arm.com>

The capabilities exposed by the PSCI generic layer depends on the hooks
populated by the platform in `plat_arm_psci_pm_ops`. Currently ARM
Standard platforms statically define this structure. However, some
platforms may want to modify the hooks at runtime before registering
them with the generic layer.

This patch introduces a new ARM platform layer API
`plat_arm_psci_override_pm_ops` which allows the platform to probe
the power controller and modify `plat_arm_psci_pm_ops` if required.
Consequently, 'plat_arm_psci_pm_ops' is no longer qualified as
`const` on ARM Standard platforms.

Change-Id: I7dbb44b7bd36c20ec14ded5ee45a96816ca2ab9d
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

There are many instances in ARM Trusted Firmware where control is
transferred to functions from which return isn't expected. Such jumps
are made using 'bl' instruction to provide the callee with the location
from which it was jumped to. Additionally, debuggers infer the caller by
examining where 'lr' register points to. If a 'bl' of the nature
described above falls at the end of an assembly function, 'lr' will be
left pointing to a location outside of the function range. This misleads
the debugger back trace.

This patch defines a 'no_ret' macro to be used when jumping to functions
from which return isn't expected. The macro ensures to use 'bl'
instruction for the jump, and also, for debug builds, places a 'nop'
instruction immediately thereafter (unless instructed otherwise) so as
to leave 'lr' pointing within the function range.

Change-Id: Ib34c69fc09197cfd57bc06e147cc8252910e01b0
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

This patch adds changes in ARM platform code to use new
version of image loading.

Following are the major changes:
  -Refactor the signatures for bl31_early_platform_setup()
   and arm_bl31_early_platform_setup() function to use
   `void *` instead of `bl31_params_t *`.
  -Introduce `plat_arm_bl2_handle_scp_bl2()` to handle
   loading of SCP_BL2 image from BL2.
  -Remove usage of reserve_mem() function from
   `arm_bl1_early_platform_setup()`
  -Extract BL32 & BL33 entrypoint info, from the link list
   passed by BL2, in `arm_bl31_early_platform_setup()`
  -Provides weak definitions for following platform functions:
     plat_get_bl_image_load_info
     plat_get_next_bl_params
     plat_flush_next_bl_params
     bl2_plat_handle_post_image_load
  -Instantiates a descriptor array for ARM platforms
   describing image and entrypoint information for
   `SCP_BL2`, `BL31`, `BL32` and `BL33` images.

All the above changes are conditionally compiled using the
`LOAD_IMAGE_V2` flag.

Change-Id: I5e88b9785a3df1a2b2bbbb37d85b8e353ca61049

This patch implements CSS platform hook to support NODE_HW_STATE PSCI
API. The platform hook queries SCP to obtain CSS power state. Power
states returned by SCP are then converted to expected PSCI return codes.

Juno's PSCI operation structure is modified to use the CSS
implementation.

Change-Id: I4a5edac0e5895dd77b51398cbd78f934831dafc0

This patch adds a WFI instruction in the default implementations of
plat_error_handler() and plat_panic_handler(). This potentially reduces
power consumption by allowing the hardware to enter a low-power state.
The same change has been made to the FVP and Juno platform ports.

Change-Id: Ia4e6e1e5bf1ed42efbba7d0ebbad7be8d5f9f173

Compile option `ARM_BOARD_OPTIMISE_MMAP` has been renamed to
`ARM_BOARD_OPTIMISE_MEM` because it now applies not only to defines
related to the translation tables but to the image size as well.

The defines `PLAT_ARM_MAX_BL1_RW_SIZE`, `PLAT_ARM_MAX_BL2_SIZE` and
`PLAT_ARM_MAX_BL31_SIZE` have been moved to the file board_arm_def.h.
This way, ARM platforms no longer have to set their own values if
`ARM_BOARD_OPTIMISE_MEM=0` and they can specify optimized values
otherwise. The common sizes have been set to the highest values used
for any of the current build configurations.

This is needed because in some build configurations some images are
running out of space. This way there is a common set of values known
to work for all of them and it can be optimized for each particular
platform if needed.

The space reserved for BL2 when `TRUSTED_BOARD_BOOT=0` has been
increased. This is needed because when memory optimisations are
disabled the values for Juno of `PLAT_ARM_MMAP_ENTRIES` and
`MAX_XLAT_TABLES` are higher. If in this situation the code is
compiled in debug mode and with "-O0", the code won't fit.

Change-Id: I70a3d8d3a0b0cad1d6b602c01a7ea334776e718e

This patch reworks type usage in generic code, drivers and ARM platform files
to make it more portable. The major changes done with respect to
type usage are as listed below:

* Use uintptr_t for storing address instead of uint64_t or unsigned long.
* Review usage of unsigned long as it can no longer be assumed to be 64 bit.
* Use u_register_t for register values whose width varies depending on
  whether AArch64 or AArch32.
* Use generic C types where-ever possible.

In addition to the above changes, this patch also modifies format specifiers
in print invocations so that they are AArch64/AArch32 agnostic. Only files
related to upcoming feature development have been reworked.

Change-Id: I9f8c78347c5a52ba7027ff389791f1dad63ee5f8

This patch enables optional PSCI functions `PSCI_STAT_COUNT` and
`PSCI_STAT_RESIDENCY` for ARM standard platforms. The optional platform
API 'translate_power_state_by_mpidr()' is implemented for the Juno
platform. 'validate_power_state()' on Juno downgrades PSCI CPU_SUSPEND
requests for the system power level to the cluster power level.
Hence, it is not suitable for validating the 'power_state' parameter
passed in a PSCI_STAT_COUNT/RESIDENCY call.

Change-Id: I9548322676fa468d22912392f2325c2a9f96e4d2

It is up to the platform to implement the new plat_crash_print_regs macro to
report all relevant platform registers helpful for troubleshooting.

plat_crash_print_regs merges or calls previously defined plat_print_gic_regs
and plat_print_interconnect_regs macros for each existing platforms.

NOTE: THIS COMMIT REQUIRES ALL PLATFORMS THAT ENABLE THE `CRASH_REPORTING`
BUILD FLAG TO MIGRATE TO USE THE NEW `plat_crash_print_regs()` MACRO. BY
DEFAULT, `CRASH_REPORTING` IS ENABLED IN DEBUG BUILDS FOR ALL PLATFORMS.

Fixes: arm-software/tf-issues#373
Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

This patch migrates ARM Standard platforms to the refactored TZC driver.

Change-Id: I2a2f60b645f73e14d8f416740c4551cec87cb1fb

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

`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

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

Current code assumes `SCP_COM_SHARED_MEM_BASE` as the base address
for BOM/SCPI protocol between AP<->SCP on all CSS platforms. To
cater for future ARM platforms this is made platform specific.
Similarly, the bit shifts of `SCP_BOOT_CONFIG_ADDR` are also made
platform specific.

Change-Id: Ie8866c167abf0229a37b3c72576917f085c142e8

Each ARM Compute Subsystem based platform implements a System Security
Control (SSC) Registers Unit. The SSC_VERSION register inside it carries
information to identify the platform. This enables ARM Trusted Firmware
to compile in support for multiple ARM platforms and choose one at
runtime. This patch adds macros to enable access to this register.
Each platform is expected to export its PART_NUMBER separately.

Additionally, it also adds juno part number.

Change-Id: I2b1d5f5b65a9c7b76c6f64480cc7cf0aef019422

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

The current FWU_SMC_UPDATE_DONE implementation incorrectly passes
an unused framework cookie through to the 1st argument in the
platform function `bl1_plat_fwu_done`. The intent is to allow
the SMC caller to pass a cookie through to this function.

This patch fixes FWU_SMC_UPDATE_DONE to pass x1 from the caller
through to `bl1_plat_fwu_done`. The argument names are updated
for clarity.

Upstream platforms currently do not use this argument so no
impact is expected.

Change-Id: I107f4b51eb03e7394f66d9a534ffab1cbc09a9b2

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

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