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This assert is present in all other linker scripts. This checks the
size of BL32 doesn't exceed its defined limit.

Change-Id: I0005959b5591d3eebd870045adafe437108bc9e1
Signed-off-by: Yann Gautier <yann.gautier@st.com>

The macro SORT_BY_ALIGNMENT is used for .text* and .rodata*. This allows
reducing the space lost to object alignment. This is an alignment with
the following patch:
ebd6efae



Some comments are also aligned with other linker scripts.

Change-Id: I2ea59edb445af0ed8c08fd883ffbf56852570d0c
Signed-off-by: Yann Gautier <yann.gautier@st.com>

Move the data section to the common header.

I slightly tweaked some scripts as follows:

[1] bl1.ld.S has ALIGN(16). I added DATA_ALIGN macro, which is 1
    by default, but overridden by bl1.ld.S. Currently, ALIGN(16)
    of the .data section is redundant because commit 41286590


    ("Fix boot failures on some builds linked with ld.lld.") padded
    out the previous section to work around the issue of LLD version
    <= 10.0. This will be fixed in the future release of LLVM, so
    I am keeping the proper way to align LMA.

[2] bl1.ld.S and bl2_el3.ld.S define __DATA_RAM_{START,END}__ instead
    of __DATA_{START,END}__. I put them out of the .data section.

[3] SORT_BY_ALIGNMENT() is missing tsp.ld.S, sp_min.ld.S, and
    mediatek/mt6795/bl31.ld.S. This commit adds SORT_BY_ALIGNMENT()
    for all images, so the symbol order in those three will change,
    but I do not think it is a big deal.

Change-Id: I215bb23c319f045cd88e6f4e8ee2518c67f03692
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The stacks section is the same for all BL linker scripts.

Move it to the common header file.

Change-Id: Ibd253488667ab4f69702d56ff9e9929376704f6c
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Move the bss section to the common header. This adds BAKERY_LOCK_NORMAL
and PMF_TIMESTAMP, which previously existed only in BL31. This is not
a big deal because unused data should not be compiled in the first
place. I believe this should be controlled by BL*_SOURCES in Makefiles,
not by linker scripts.

I investigated BL1, BL2, BL2U, BL31 for plat=fvp, and BL2-AT-EL3,
BL31, BL31 for plat=uniphier. I did not see any more  unexpected
code addition.

The bss section has bigger alignment. I added BSS_ALIGN for this.

Currently, SORT_BY_ALIGNMENT() is missing in sp_min.ld.S, and with this
change, the BSS symbols in SP_MIN will be sorted by the alignment.
This is not a big deal (or, even better in terms of the image size).

Change-Id: I680ee61f84067a559bac0757f9d03e73119beb33
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The common section data are repeated in many linker scripts (often
twice in each script to support SEPARATE_CODE_AND_RODATA). When you
add a new read-only data section, you end up with touching lots of
places.

After this commit, you will only need to touch bl_common.ld.h when
you add a new section to RODATA_COMMON.

Replace a series of RO section with RODATA_COMMON, which contains
6 sections, some of which did not exist before.

This is not a big deal because unneeded data should not be compiled
in the first place. I believe this should be controlled by BL*_SOURCES
in Makefiles, not by linker scripts.

When I was working on this commit, the BL1 image size increased
due to the fconf_populator. Commit c452ba15

 ("fconf: exclude
fconf_dyn_cfg_getter.c from BL1_SOURCES") fixed this issue.

I investigated BL1, BL2, BL2U, BL31 for plat=fvp, and BL2-AT-EL3,
BL31, BL31 for plat=uniphier. I did not see any more  unexpected
code addition.

Change-Id: I5d14d60dbe3c821765bce3ae538968ef266f1460
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

These are mostly used to collect data from special structure,
and repeated in many linker scripts.

To differentiate the alignment size between aarch32/aarch64, I added
a new macro STRUCT_ALIGN.

While I moved the PMF_SVC_DESCS, I dropped #if ENABLE_PMF conditional.
As you can see in include/lib/pmf/pmf_helpers.h, PMF_REGISTER_SERVICE*
are no-op when ENABLE_PMF=0. So, pmf_svc_descs and pmf_timestamp_array
data are not populated.

Change-Id: I3f4ab7fa18f76339f1789103407ba76bda7e56d0
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

sp_min.ld.S is used for aarch32.

ALIGN(4) is used for alignment of the other structures. I do not think
struct fconf_populator is a special case. Let's use ALIGN(4) here too.

Perhaps, this is just a copy-paste mistake of commit 26d1e0c3


("fconf: necessary modifications to support fconf in BL31 & SP_MIN").

Change-Id: I29f4c68680842c1b5ef913934b4ccf378e9bfcfb
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Necessary infrastructure added to integrate fconf framework in BL31 & SP_MIN.
Created few populator() functions which parse HW_CONFIG device tree
and registered them with fconf framework. Many of the changes are
only applicable for fvp platform.

This patch:
1. Adds necessary symbols and sections in BL31, SP_MIN linker script
2. Adds necessary memory map entry for translation in BL31, SP_MIN
3. Creates an abstraction layer for hardware configuration based on
   fconf framework
4. Adds necessary changes to build flow (makefiles)
5. Minimal callback to read hw_config dtb for capturing properties
   related to GIC(interrupt-controller node)
6. updates the fconf documentation

Change-Id: Ib6292071f674ef093962b9e8ba0d322b7bf919af
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>

TF-A has so many linker scripts, at least one linker script for each BL
image, and some platforms have their own ones. They duplicate quite
similar code (and comments).

When we add some changes to linker scripts, we end up with touching
so many files. This is not nice in the maintainability perspective.

When you look at Linux kernel, the common code is macrofied in
include/asm-generic/vmlinux.lds.h, which is included from each arch
linker script, arch/*/kernel/vmlinux.lds.S

TF-A can follow this approach. Let's factor out the common code into
include/common/bl_common.ld.h

As a start point, this commit factors out the xlat_table section.

Change-Id: Ifa369e9b48e8e12702535d721cc2a16d12397895
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Ported the pmf asm macros and the asm code in the bl31 entrypoint
necessary for the instrumentation to AArch32.

Since smc dispatch is handled by the bl32 payload on AArch32, we
provide this service only if AARCH32_SP=sp_min is set.
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
Change-Id: Id33b7e9762ae86a4f4b40d7f1b37a90e5130c8ac

Similar to bl31 allow sp_min to also include a platform-specific
linker script. This allows for example to place specific code in
other memories of the system, like resume code in sram, while the
main tf-a lives in ddr.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Change-Id: I67642f7bfca036b5d51eb0fa092b479a647a9cc1

This patch introduces explicit linker variables to mark the start and
end of the per-cpu bakery lock section to help bakery_lock_normal.c
calculate the size of the section. This patch removes the previously
used '__PERCPU_BAKERY_LOCK_SIZE__' linker variable to make the code
uniform across GNU linker and ARM linker.

Change-Id: Ie0c51702cbc0fe8a2076005344a1fcebb48e7cca
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

Corrects typos in core code, documentation files, drivers, Arm
platforms and services.

None of the corrections affect code; changes are limited to comments
and other documentation.

Change-Id: I5c1027b06ef149864f315ccc0ea473e2a16bfd1d
Signed-off-by: Paul Beesley <paul.beesley@arm.com>

Enforce full include path for includes. Deprecate old paths.

The following folders inside include/lib have been left unchanged:

- include/lib/cpus/${ARCH}
- include/lib/el3_runtime/${ARCH}

The reason for this change is that having a global namespace for
includes isn't a good idea. It defeats one of the advantages of having
folders and it introduces problems that are sometimes subtle (because
you may not know the header you are actually including if there are two
of them).

For example, this patch had to be created because two headers were
called the same way: e0ea0928 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca339

 ("Move include and
source files to logical locations"). At that time, there weren't too
many headers so it wasn't a real issue. However, time has shown that
this creates problems.

Platforms that want to preserve the way they include headers may add the
removed paths to PLAT_INCLUDES, but this is discouraged.

Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

These sections are required by clang when the code is compiled for
aarch32. These sections are related to the unwind of the stack in
exceptions, but in the way that clang defines and uses them, the
garbage collector cannot get rid of them.

Change-Id: I085efc0cf77eae961d522472f72c4b5bad2237ab
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Clang linker doesn't support NEXT. As we are not using the MEMORY command
to define discontinuous memory for the output file in any of the linker
scripts, ALIGN and NEXT are equivalent.

Change-Id: I867ffb9c9a76d4e81c9ca7998280b2edf10efea0
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

When the MMU is enabled and the translation tables are mapped, data
read/writes to the translation tables are made using the attributes
specified in the translation tables themselves. However, the MMU
performs table walks with the attributes specified in TCR_ELx. They are
completely independent, so special care has to be taken to make sure
that they are the same.

This has to be done manually because it is not practical to have a test
in the code. Such a test would need to know the virtual memory region
that contains the translation tables and check that for all of the
tables the attributes match the ones in TCR_ELx. As the tables may not
even be mapped at all, this isn't a test that can be made generic.

The flags used by enable_mmu_xxx() have been moved to the same header
where the functions are.

Also, some comments in the linker scripts related to the translation
tables have been fixed.

Change-Id: I1754768bffdae75f53561b1c4a5baf043b45a304
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

This patch fixes a couple of issues for AArch32 builds on ARM reference
platforms :

1. The arm_def.h previously defined the same BL32_BASE value for AArch64 and
   AArch32 build. Since BL31 is not present in AArch32 mode, this meant that
   the BL31 memory is empty when built for AArch32. Hence this patch allocates
   BL32 to the memory region occupied by BL31 for AArch32 builds.

   As a side-effect of this change, the ARM_TSP_RAM_LOCATION macro cannot
   be used to control the load address of BL32 in AArch32 mode which was
   never the intention of the macro anyway.

2. A static assert is added to sp_min linker script to check that the progbits
   are within the bounds expected when overlaid with other images.

3. Fix specifying `SPD` when building Juno for AArch32 mode. Due to the quirks
   involved when building Juno for AArch32 mode, the build option SPD needed to
   specifed. This patch corrects this and also updates the documentation in the
   user-guide.

4. Exclude BL31 from the build and FIP when building Juno for AArch32 mode. As
   a result the previous assumption that BL31 must be always present is removed
   and the certificates for BL31 is only generated if `NEED_BL31` is defined.

Change-Id: I1c39bbc0abd2be8fbe9f2dea2e9cb4e3e3e436a8
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

When defining different sections in linker scripts it is needed to align
them to multiples of the page size. In most linker scripts this is done
by aligning to the hardcoded value 4096 instead of PAGE_SIZE.

This may be confusing when taking a look at all the codebase, as 4096
is used in some parts that aren't meant to be a multiple of the page
size.

Change-Id: I36c6f461c7782437a58d13d37ec8b822a1663ec1
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

This light-weight framework enables some EL3 components to publish
events which other EL3 components can subscribe to. Publisher can
optionally pass opaque data for subscribers. The order in which
subscribers are called is not defined.

Firmware design updated.

Change-Id: I24a3a70b2b1dedcb1f73cf48313818aebf75ebb6
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.

NOTE: Files that have been imported by FreeBSD have not been modified.

[0]: https://spdx.org/



Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

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

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

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

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

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

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

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

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

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

Fixes ARM-software/tf-issues#408

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

This patch uses the `el3_entrypoint_common` macro to initialize
CPU registers, in SP_MIN entrypoint.s file, in both cold and warm
boot path. It also adds conditional compilation, in cold and warm
boot entry path, based on RESET_TO_SP_MIN.

Change-Id: Id493ca840dc7b9e26948dc78ee928e9fdb76b9e4

This patch adds a minimal AArch32 secure payload SP_MIN. It relies on PSCI
library to initialize the normal world context. It runs in Monitor mode
and uses the runtime service framework to handle SMCs. It is added as
a BL32 component in the Trusted Firmware source tree.

Change-Id: Icc04fa6b242025a769c1f6c7022fde19459c43e9

At the moment, all BL images share a similar memory layout: they start
with their code section, followed by their read-only data section.
The two sections are contiguous in memory. Therefore, the end of the
code section and the beginning of the read-only data one might share
a memory page. This forces both to be mapped with the same memory
attributes. As the code needs to be executable, this means that the
read-only data stored on the same memory page as the code are
executable as well. This could potentially be exploited as part of
a security attack.

This patch introduces a new build flag called
SEPARATE_CODE_AND_RODATA, which isolates the code and read-only data
on separate memory pages. This in turn allows independent control of
the access permissions for the code and read-only data.

This has an impact on memory footprint, as padding bytes need to be
introduced between the code and read-only data to ensure the
segragation of the two. To limit the memory cost, the memory layout
of the read-only section has been changed in this case.

 - When SEPARATE_CODE_AND_RODATA=0, the layout is unchanged, i.e.
   the read-only section still looks like this (padding omitted):

   |        ...        |
   +-------------------+
   | Exception vectors |
   +-------------------+
   |  Read-only data   |
   +-------------------+
   |       Code        |
   +-------------------+ BLx_BASE

   In this case, the linker script provides the limits of the whole
   read-only section.

 - When SEPARATE_CODE_AND_RODATA=1, the exception vectors and
   read-only data are swapped, such that the code and exception
   vectors are contiguous, followed by the read-only data. This
   gives the following new layout (padding omitted):

   |        ...        |
   +-------------------+
   |  Read-only data   |
   +-------------------+
   | Exception vectors |
   +-------------------+
   |       Code        |
   +-------------------+ BLx_BASE

   In this case, the linker script now exports 2 sets of addresses
   instead: the limits of the code and the limits of the read-only
   data. Refer to the Firmware Design guide for more details. This
   provides platform code with a finer-grained view of the image
   layout and allows it to map these 2 regions with the appropriate
   access permissions.

Note that SEPARATE_CODE_AND_RODATA applies to all BL images.

Change-Id: I936cf80164f6b66b6ad52b8edacadc532c935a49

This patch adds Performance Measurement Framework(PMF) in the
ARM Trusted Firmware. PMF is implemented as a library and the
SMC interface is provided through ARM SiP service.

The PMF provides capturing, storing, dumping and retrieving the
time-stamps, by enabling the development of services by different
providers, that can be easily integrated into ARM Trusted Firmware.
The PMF capture and retrieval APIs can also do appropriate cache
maintenance operations to the timestamp memory when the caller
indicates so.

`pmf_main.c` consists of core functions that implement service
registration, initialization, storing, dumping and retrieving
the time-stamp.
`pmf_smc.c` consists SMC handling for registered PMF services.
`pmf.h` consists of the macros that can be used by the PMF service
providers to register service and declare time-stamp functions.
`pmf_helpers.h` consists of internal macros that are used by `pmf.h`

By default this feature is disabled in the ARM trusted firmware.
To enable it set the boolean flag `ENABLE_PMF` to 1.

NOTE: The caller is responsible for specifying the appropriate cache
maintenance flags and for acquiring/releasing appropriate locks
before/after capturing/retrieving the time-stamps.

Change-Id: Ib45219ac07c2a81b9726ef6bd9c190cc55e81854

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

When a platform port does not define PLAT_PERCPU_BAKERY_LOCK_SIZE, the total
memory that should be allocated per-cpu to accommodate all bakery locks is
calculated by the linker in bl31.ld.S. The linker stores this value in the
__PERCPU_BAKERY_LOCK_SIZE__ linker symbol. The runtime value of this symbol is
different from the link time value as the symbol is relocated into the current
section (.bss). This patch fixes this issue by marking the symbol as ABSOLUTE
which allows it to retain its correct value even at runtime.

The description of PLAT_PERCPU_BAKERY_LOCK_SIZE in the porting-guide.md has been
made clearer as well.

Change-Id: Ia0cfd42f51deaf739d792297e60cad5c6e6e610b

On the ARMv8 architecture, cache maintenance operations by set/way on the last
level of integrated cache do not affect the system cache. This means that such a
flush or clean operation could result in the data being pushed out to the system
cache rather than main memory. Another CPU could access this data before it
enables its data cache or MMU. Such accesses could be serviced from the main
memory instead of the system cache. If the data in the sysem cache has not yet
been flushed or evicted to main memory then there could be a loss of
coherency. The only mechanism to guarantee that the main memory will be updated
is to use cache maintenance operations to the PoC by MVA(See section D3.4.11
(System level caches) of ARMv8-A Reference Manual (Issue A.g/ARM DDI0487A.G).

This patch removes the reliance of Trusted Firmware on the flush by set/way
operation to ensure visibility of data in the main memory. Cache maintenance
operations by MVA are now used instead. The following are the broad category of
changes:

1. The RW areas of BL2/BL31/BL32 are invalidated by MVA before the C runtime is
   initialised. This ensures that any stale cache lines at any level of cache
   are removed.

2. Updates to global data in runtime firmware (BL31) by the primary CPU are made
   visible to secondary CPUs using a cache clean operation by MVA.

3. Cache maintenance by set/way operations are only used prior to power down.

NOTE: NON-UPSTREAM TRUSTED FIRMWARE CODE SHOULD MAKE EQUIVALENT CHANGES IN
ORDER TO FUNCTION CORRECTLY ON PLATFORMS WITH SUPPORT FOR SYSTEM CACHES.

Fixes ARM-software/tf-issues#205

Change-Id: I64f1b398de0432813a0e0881d70f8337681f6e9a

This patch unifies the bakery lock api's across coherent and normal
memory implementation of locks by using same data type `bakery_lock_t`
and similar arguments to functions.

A separate section `bakery_lock` has been created and used to allocate
memory for bakery locks using `DEFINE_BAKERY_LOCK`. When locks are
allocated in normal memory, each lock for a core has to spread
across multiple cache lines. By using the total size allocated in a
separate cache line for a single core at compile time, the memory for
other core locks is allocated at link time by multiplying the single
core locks size with (PLATFORM_CORE_COUNT - 1). The normal memory lock
algorithm now uses lock address instead of the `id` in the per_cpu_data.
For locks allocated in coherent memory, it moves locks from
tzfw_coherent_memory to bakery_lock section.

The bakery locks are allocated as part of bss or in coherent memory
depending on usage of coherent memory. Both these regions are
initialised to zero as part of run_time_init before locks are used.
Hence, bakery_lock_init() is made an empty function as the lock memory
is already initialised to zero.

The above design lead to the removal of psci bakery locks from
non_cpu_power_pd_node to psci_locks.

NOTE: THE BAKERY LOCK API WHEN USE_COHERENT_MEM IS NOT SET HAS CHANGED.
THIS IS A BREAKING CHANGE FOR ALL PLATFORM PORTS THAT ALLOCATE BAKERY
LOCKS IN NORMAL MEMORY.

Change-Id: Ic3751c0066b8032dcbf9d88f1d4dc73d15f61d8b

This patch extends the build option `USE_COHERENT_MEMORY` to
conditionally remove coherent memory from the memory maps of
all boot loader stages. The patch also adds necessary
documentation for coherent memory removal in firmware-design,
porting and user guides.

Fixes ARM-Software/tf-issues#106

Change-Id: I260e8768c6a5c2efc402f5804a80657d8ce38773

This patch fixes the incorrect value of the LENGTH attribute in
the linker scripts. This attribute must define the memory size, not
the limit address.

Fixes ARM-software/tf-issues#252

Change-Id: I328c38b9ec502debe12046a8912d7dfc54610c46

This patch introduces a framework which will allow CPUs to perform
implementation defined actions after a CPU reset, during a CPU or cluster power
down, and when a crash occurs. CPU specific reset handlers have been implemented
in this patch. Other handlers will be implemented in subsequent patches.

Also moved cpu_helpers.S to the new directory lib/cpus/aarch64/.

Change-Id: I1ca1bade4d101d11a898fb30fea2669f9b37b956

Secure ROM at address 0x0000_0000 is defined as FVP_TRUSTED_ROM
Secure RAM at address 0x0400_0000 is defined as FVP_TRUSTED_SRAM
Secure RAM at address 0x0600_0000 is defined as FVP_TRUSTED_DRAM

BLn_BASE and BLn_LIMIT definitions have been updated and are based on
these new memory regions.

The available memory for each bootloader in the linker script is
defined by BLn_BASE and BLn_LIMIT, instead of the complete memory
region.

TZROM_BASE/SIZE and TZRAM_BASE/SIZE are no longer required as part of
the platform porting.

FVP common definitions are defined in fvp_def.h while platform_def.h
contains exclusively (with a few exceptions) the definitions that are
mandatory in the porting guide. Therefore, platform_def.h now includes
fvp_def.h instead of the other way around.

Porting guide has been updated to reflect these changes.

Change-Id: I39a6088eb611fc4a347db0db4b8f1f0417dbab05

This patch re-organizes the memory layout on FVP as to give the
BL3-2 image as much memory as possible.

Considering these two facts:
 - not all images need to live in memory at the same time. Once
   in BL3-1, the memory used by BL1 and BL2 can be reclaimed.
 - when BL2 loads the BL3-1 and BL3-2 images, it only considers the
   PROGBITS sections of those 2 images. The memory occupied by the
   NOBITS sections will be touched only at execution of the BL3-x
   images;
Then it is possible to choose the different base addresses such that
the NOBITS sections of BL3-1 and BL3-2 overlay BL1 and BL2.

On FVP we choose to put:
 - BL1 and BL3-1 at the top of the Trusted RAM, with BL3-1 NOBITS
   sections overlaying BL1;
 - BL3-2 at the bottom of the Trusted RAM, with its NOBITS sections
   overlaying BL2;

This is illustrated by the following diagram:

0x0404_0000 ------------    ------------------
            |   BL1    | <= |  BL3-1 NOBITS  |
            ------------ <= ------------------
            |          | <= | BL3-1 PROGBITS |
            ------------    ------------------
            |   BL2    | <= |  BL3-2 NOBITS  |
            ------------ <= ------------------
            |          | <= | BL3-2 PROGBITS |
0x0400_0000 ------------    ------------------

New platform-specific constants have been introduced to easily check
at link time that BL3-1 and BL3-2 PROGBITS sections don't overwrite
BL1 and BL2. These are optional and the platform code is free to define
them or not. If not defined, the linker won't attempt to check
image overlaying.

Fixes ARM-software/tf-issues#117

Change-Id: I5981d1c3d66ee70eaac8bd052630c9ac6dd8b042

Previously, platform.h contained many declarations and definitions
used for different purposes. This file has been split so that:

* Platform definitions used by common code that must be defined
  by the platform are now in platform_def.h. The exact include
  path is exported through $PLAT_INCLUDES in the platform makefile.

* Platform definitions specific to the FVP platform are now in
  /plat/fvp/fvp_def.h.

* Platform API declarations specific to the FVP platform are now
  in /plat/fvp/fvp_private.h.

* The remaining platform API declarations that must be ported by
  each platform are still in platform.h but this file has been
  moved to /include/plat/common since this can be shared by all
  platforms.

Change-Id: Ieb3bb22fbab3ee8027413c6b39a783534aee474a

Currently the platform code gets to define the base address of each
boot loader image. However, the linker scripts couteract this
flexibility by enforcing a fixed overall layout of the different
images. For example, they require that the BL3-1 image sits below
the BL2 image. Choosing BL3-1 and BL2 base addresses in such a way
that it violates this constraint makes the build fail at link-time.

This patch requires the platform code to now define a limit address
for each image. The linker scripts check that the image fits within
these bounds so they don't rely anymore on the position of a given
image in regard to the others.

Fixes ARM-software/tf-issues#163

Change-Id: I8c108646825da19a6a8dfb091b613e1dd4ae133c

All common functions are being built into all binary images,
whether or not they are actually used. This change enables the
use of -ffunction-sections, -fdata-sections and --gc-sections
in the compiler and linker to remove unused code and data from
the images.

Change-Id: Ia9f78c01054ac4fa15d145af38b88a0d6fb7d409

At present, the entry point for each BL image is specified via the
Makefiles and provided on the command line to the linker. When using a
link script the entry point should rather be specified via the ENTRY()
directive in the link script.

This patch updates linker scripts of all BL images to specify the entry
point using the ENTRY() directive. It also removes the --entry flag
passed to the linker through Makefile.

Fixes issue ARM-software/tf-issues#66

Change-Id: I1369493ebbacea31885b51185441f6b628cf8da0