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Due to incorrect conditional compilation checks, bakery locks were
excluded from the CCN driver and the power controller driver for FVP
when BL32 was built as the EL3 Runtime Software in AArch32 mode.
This patch corrects the same.

Change-Id: Ib1f163d9167a5c38e4d622232c4835cad9c235aa
Signed-off-by: Soby Mathew <soby.mathew@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>

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.

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>

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>

As with other ARM platform GIC APIs, these directly invoke the GICv3
driver APIs for Redistributor power management.

For the sake of uniform GIC API, empty stubs are placed for those GIC
drivers that lack Redistributor component.

Change-Id: Iad0d760d4dbca790998f7768cda621ff3b15a864
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.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 now deprecated ADDR_SPACE_SIZE has been replaced by the two
defines PLAT_PHY_ADDR_SPACE_SIZE and PLAT_VIRT_ADDR_SPACE_SIZE.

Change-Id: I027a2f02f47ab2f679b8979a6dbfb0f08270a1a4
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@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>

This patch introduces an additional layer of abstraction between
CSS power management hooks and the SCPI driver. A new set of APIs
are introduced in order to abstract out power management operations
from underlying communication mechanism with the SCP.

The SCPI and the associated MHU drivers are moved into a `drivers`
folder in CSS. The new SCP communication abstraction layer is added
in the `drivers/scp` folder. The existing CSS power management
uses the new APIs to reflect this abstraction.

Change-Id: I7d775129fc0558e9703c2724523fb8f0a916838c
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

This patch adds ARM SiP service for use by ARM standard platforms.
This service is added to support the SMC interface for the Performance
measurement framework(PMF).

Change-Id: I26f5712f9ab54f5f721dd4781e35a16f40aacc44
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This patch adds support in SP_MIN to receive generic and
platform specific arguments from BL2.

The new signature is as following:
    void sp_min_early_platform_setup(void *from_bl2,
         void *plat_params_from_bl2);

ARM platforms have been modified to use this support.

Note: Platforms may break if using old signature.
      Default value for RESET_TO_SP_MIN is changed to 0.

Change-Id: I008d4b09fd3803c7b6231587ebf02a047bdba8d0

This patch adds common changes to support AArch32 state in
BL1 and BL2. Following are the changes:

* Added functions for disabling MMU from Secure state.
* Added AArch32 specific SMC function.
* Added semihosting support.
* Added reporting of unhandled exceptions.
* Added uniprocessor stack support.
* Added `el3_entrypoint_common` macro that can be
  shared by BL1 and BL32 (SP_MIN) BL stages. The
  `el3_entrypoint_common` is similar to the AArch64
  counterpart with the main difference in the assembly
  instructions and the registers that are relevant to
  AArch32 execution state.
* Enabled `LOAD_IMAGE_V2` flag in Makefile for
  `ARCH=aarch32` and added check to make sure that
  platform has not overridden to disable it.

Change-Id: I33c6d8dfefb2e5d142fdfd06a0f4a7332962e1a3

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 adds changes in BL1 & BL2 to use new version
of image loading to load the BL images.

Following are the changes in BL1:
  -Use new version of load_auth_image() to load BL2
  -Modified `bl1_init_bl2_mem_layout()` to remove using
   `reserve_mem()` and to calculate `bl2_mem_layout`.
   `bl2_mem_layout` calculation now assumes that BL1 RW
   data is at the top of the bl1_mem_layout, which is more
   restrictive than the previous BL1 behaviour.

Following are the changes in BL2:
  -The `bl2_main.c` is refactored and all the functions
   for loading BLxx images are now moved to `bl2_image_load.c`
   `bl2_main.c` now calls a top level `bl2_load_images()` to
   load all the images that are applicable in BL2.
  -Added new file `bl2_image_load_v2.c` that uses new version
   of image loading to load the BL images in BL2.

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

Change-Id: Ic6dcde5a484495bdc05526d9121c59fa50c1bf23

This patch adds capability to load BL images based on image
descriptors instead of hard coded way of loading BL images.
This framework is designed such that it can be readily adapted
by any BL stage that needs to load images.

In order to provide the above capability the following new
platform functions are introduced:

  bl_load_info_t *plat_get_bl_image_load_info(void);
    This function returns pointer to the list of images that the
    platform has populated to load.

  bl_params_t *plat_get_next_bl_params(void);
    This function returns a pointer to the shared memory that the
    platform has kept aside to pass trusted firmware related
    information that next BL image needs.

  void plat_flush_next_bl_params(void);
    This function flushes to main memory all the params that
    are passed to next image.

  int bl2_plat_handle_post_image_load(unsigned int image_id)
    This function can be used by the platforms to update/use
    image information for given `image_id`.

`desc_image_load.c` contains utility functions which can be used
by the platforms to generate, load and executable, image list
based on the registered image descriptors.

This patch also adds new version of `load_image/load_auth_image`
functions in-order to achieve the above capability.

Following are the changes for the new version as compared to old:
  - Refactor the signature and only keep image_id and image_info_t
    arguments. Removed image_base argument as it is already passed
    through image_info_t. Given that the BL image base addresses and
    limit/size are already provided by the platforms, the meminfo_t
    and entry_point_info arguments are not needed to provide/reserve
    the extent of free memory for the given BL image.

  - Added check for the image size against the defined max size.
    This is needed because the image size could come from an
    unauthenticated source (e.g. the FIP header).
    To make this check, new member is added to the image_info_t
    struct for identifying the image maximum size.

New flag `LOAD_IMAGE_V2` is added in the Makefile.
Default value is 0.

NOTE: `TRUSTED_BOARD_BOOT` is currently not supported when
      `LOAD_IMAGE_V2` is enabled.

Change-Id: Ia7b643f4817a170d5a2fbf479b9bc12e63112e79

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 couple of missing forward declarations in plat_arm.h
so that all types it references are known within this header file,
without relying on previous header inclusions. This concerns the
meminfo and bl31_params structures, which are defined in bl_common.h.
Other external types referenced from plat_arm.h (e.g. mmap_region_t)
get declared through header files included by arm_plat.h so they
don't need forward declarations.

Change-Id: I471d5aa487919aff3fa979fc65e053f4f5b0ef32

This patch implements the support for SP_MIN in FVP. The SP_MIN platform
APIs are implemented and the required makefile support is added for FVP.

Change-Id: Id50bd6093eccbd5e38894e3fd2b20d5baeac5452

This patch adds AArch32 support for FVP and implements common platform APIs
like `plat_get_my_stack`, `plat_set_my_stack`, `plat_my_core_cos` for AArch32.
Only Multi Processor(MP) implementations of these functions are considered in
this patch. The ARM Standard platform layer helpers are implemented for
AArch32 and the common makefiles are modified to cater for both AArch64 and
AArch32 builds. Compatibility with the deprecated platform API is not
supported for AArch32.

Change-Id: Iad228400613eec91abf731b49e21a15bcf2833ea

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

On ARM CSS platforms, the whole flash used to be mapped as executable.
This is not required, given that the flash is used to store the BL1
and FIP images and:

 - The FIP is not executed in place, its images are copied to RAM
   and executed from there.

 - BL1 is executed in place from flash but only its code needs to be
   mapped as executable and platform code takes care of re-mapping
   BL1's read-only section as executable.

Therefore, this patch now maps the flash as non-executable by default
on these platforms. This increases security by restricting the
executable region to what is strictly needed.

This patch also adds some comments to clarify the memory mapping
attributes on these platforms.

Change-Id: I4db3c145508bea1f43fbe0f6dcd551e1aec1ecd3

The arm_setup_page_tables() function used to expect a single set of
addresses defining the extents of the whole read-only section, code
and read-only data mixed up, which was mapped as executable.

This patch changes this behaviour. arm_setup_page_tables() now
expects 2 separate sets of addresses:

 - the extents of the code section;
 - the extents of the read-only data section.

The code is mapped as executable, whereas the data is mapped as
execute-never. New #defines have been introduced to identify the
extents of the code and the read-only data section. Given that
all BL images except BL1 share the same memory layout and linker
script structure, these #defines are common across these images.
The slight memory layout differences in BL1 have been handled by
providing values specific to BL1.

Note that this patch also affects the Xilinx platform port, which
uses the arm_setup_page_tables() function. It has been updated
accordingly, such that the memory mappings on this platform are
unchanged. This is achieved by passing null values as the extents
of the read-only data section so that it is ignored. As a result,
the whole read-only section is still mapped as executable.

Fixes ARM-software/tf-issues#85

Change-Id: I1f95865c53ce6e253a01286ff56e0aa1161abac5

This patch introduces a new header file: include/lib/utils.h.
Its purpose is to provide generic macros and helper functions that
are independent of any BL image, architecture, platform and even
not specific to Trusted Firmware.

For now, it contains only 2 macros: ARRAY_SIZE() and
IS_POWER_OF_TWO(). These were previously defined in bl_common.h and
xlat_tables.c respectively.

bl_common.h includes utils.h to retain compatibility for platforms
that relied on bl_common.h for the ARRAY_SIZE() macro. Upstream
platform ports that use this macro have been updated to include
utils.h.

Change-Id: I960450f54134f25d1710bfbdc4184f12c049a9a9

This patch introduces the arm_setup_page_tables() function to
set up page tables on ARM platforms. It replaces the
arm_configure_mmu_elx() functions and does the same thing except
that it doesn't enable the MMU at the end. The idea is to reduce
the amount of per-EL code that is generated by the C preprocessor
by splitting the memory regions definitions and page tables creation
(which is generic) from the MMU enablement (which is the only per-EL
configuration).

As a consequence, the call to the enable_mmu_elx() function has been
moved up into the plat_arch_setup() hook. Any other ARM standard
platforms that use the functions `arm_configure_mmu_elx()` must be
updated.

Change-Id: I6f12a20ce4e5187b3849a8574aac841a136de83d

A production ROM with TBB enabled must have the ability to boot test software
before a real ROTPK is deployed (e.g. manufacturing mode). Previously the
function plat_get_rotpk_info() must return a valid ROTPK for TBB to succeed.
This patch adds an additional bit `ROTPK_NOT_DEPLOYED` in the output `flags`
parameter from plat_get_rotpk_info(). If this bit is set, then the ROTPK
in certificate is used without verifying against the platform value.

Fixes ARM-software/tf-issues#381

Change-Id: Icbbffab6bff8ed76b72431ee21337f550d8fdbbb

Added plat_get_syscnt_freq2, which is a 32 bit variant of the 64 bit
plat_get_syscnt_freq. The old one has been flagged as deprecated.
Common code has been updated to use this new version. Porting guide
has been updated.

Change-Id: I9e913544926c418970972bfe7d81ee88b4da837e

This patch moves the definition for `plat_get_syscnt_freq()`
from arm_bl31_setup.c to arm_common.c. This could be useful
in case a delay timer needs to be installed based on the
generic timer in other BLs.
This patch also modifies the return type for this function
from `uint64_t` to `unsigned long long` within ARM and other
platform files.

Change-Id: Iccdfa811948e660d4fdcaae60ad1d700e4eda80d

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>

Previously, when building TF without SPD support, BL2 tried to load a
BL32 image from the FIP and fails to find one, which resulted on
warning messages on the console. Even if there is a BL32 image in the
FIP it shouldn't be loaded because there is no way to transfer
control to the Secure Payload without SPD support.

The Makefile has been modified to pass a define of the form
SPD_${SPD} to the source code the same way it's done for PLAT. The
define SPD_none is then used to undefine BL32_BASE when BL32 is not
used to prevent BL2 from trying to load a BL32 image and failing,
thus removing the warning messages mentioned above.

Fixes ARM-software/tf-issues#287

Change-Id: Ifeb6f1c26935efb76afd353fea88e87ba09e9658

This patch modifies the return type of the platform API
`plat_get_ns_image_entrypoint()` from `unsigned long` to
`uintptr_t` in accordance with the coding guidelines.

Change-Id: Icb4510ca98b706aa4d535fe27e203394184fb4ca

This patch adds support to program TrustZone protection on ARM platforms that
implement a DMC-500. arm_dmc_500.c has been added which implements the
arm_dmc_tzc_setup() function. This function relies on constants related to TZC
programming that are exported by each platform to program TrustZone protection
using the DMC-500 TrustZone controller driver. This function should be called
from plat_arm_security_setup() which is implemented by each platform.

Change-Id: I5400bdee9e4b29155fd11296a40693d512312f29

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

Change-Id: I2a2f60b645f73e14d8f416740c4551cec87cb1fb

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

This patch adds an option to the ARM common platforms to load BL31 in the
TZC secured DRAM instead of the default secure SRAM.

To enable this feature, set `ARM_BL31_IN_DRAM` to 1 in build options.
If TSP is present, then setting this option also sets the TSP location
to DRAM and ignores the `ARM_TSP_RAM_LOCATION` build flag.

To use this feature, BL2 platform code must map in the DRAM used by
BL31. The macro ARM_MAP_BL31_SEC_DRAM is provided for this purpose.
Currently, only the FVP BL2 platform code maps in this DRAM.

Change-Id: If5f7cc9deb569cfe68353a174d4caa48acd78d67

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