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Many asserts depend on code that is conditionally compiled based on the
DEBUG define. This patch modifies the conditional inclusion of such code
so that it is based on the ENABLE_ASSERTIONS build option.

Change-Id: I6406674788aa7e1ad7c23d86ce94482ad3c382bd
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Introduce new build option ENABLE_STACK_PROTECTOR. It enables
compilation of all BL images with one of the GCC -fstack-protector-*
options.

A new platform function plat_get_stack_protector_canary() is introduced.
It returns a value that is used to initialize the canary for stack
corruption detection. Returning a random value will prevent an attacker
from predicting the value and greatly increase the effectiveness of the
protection.

A message is printed at the ERROR level when a stack corruption is
detected.

To be effective, the global data must be stored at an address
lower than the base of the stacks. Failure to do so would allow an
attacker to overwrite the canary as part of an attack which would void
the protection.

FVP implementation of plat_get_stack_protector_canary is weak as
there is no real source of entropy on the FVP. It therefore relies on a
timer's value, which could be predictable.

Change-Id: Icaaee96392733b721fa7c86a81d03660d3c1bc06
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

Call console_flush() before execution either terminates or leaves an
exception level.

Fixes: ARM-software/tf-issues#123

Change-Id: I64eeb92effb039f76937ce89f877b68e355588e3
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

These source file definitions should be defined in generic
Makefiles so that all platforms can benefit. Ensure that the
symbols are properly marked as weak so they can be overridden
by platforms.

NOTE: This change is a potential compatibility break for
non-upstream platforms.

Change-Id: I7b892efa9f2d6d216931360dc6c436e1d10cffed
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>

The errata reporting policy is as follows:

  - If an errata workaround is enabled:

    - If it applies (i.e. the CPU is affected by the errata), an INFO
      message is printed, confirming that the errata workaround has been
      applied.

    - If it does not apply, a VERBOSE message is printed, confirming
      that the errata workaround has been skipped.

  - If an errata workaround is not enabled, but would have applied had
    it been, a WARN message is printed, alerting that errata workaround
    is missing.

The CPU errata messages are printed by both BL1 (primary CPU only) and
runtime firmware on debug builds, once for each CPU/errata combination.

Relevant output from Juno r1 console when ARM Trusted Firmware is built
with PLAT=juno LOG_LEVEL=50 DEBUG=1:

  VERBOSE: BL1: cortex_a57: errata workaround for 806969 was not applied
  VERBOSE: BL1: cortex_a57: errata workaround for 813420 was not applied
  INFO:    BL1: cortex_a57: errata workaround for disable_ldnp_overread was applied
  WARNING: BL1: cortex_a57: errata workaround for 826974 was missing!
  WARNING: BL1: cortex_a57: errata workaround for 826977 was missing!
  WARNING: BL1: cortex_a57: errata workaround for 828024 was missing!
  WARNING: BL1: cortex_a57: errata workaround for 829520 was missing!
  WARNING: BL1: cortex_a57: errata workaround for 833471 was missing!
  ...
  VERBOSE: BL31: cortex_a57: errata workaround for 806969 was not applied
  VERBOSE: BL31: cortex_a57: errata workaround for 813420 was not applied
  INFO:    BL31: cortex_a57: errata workaround for disable_ldnp_overread was applied
  WARNING: BL31: cortex_a57: errata workaround for 826974 was missing!
  WARNING: BL31: cortex_a57: errata workaround for 826977 was missing!
  WARNING: BL31: cortex_a57: errata workaround for 828024 was missing!
  WARNING: BL31: cortex_a57: errata workaround for 829520 was missing!
  WARNING: BL31: cortex_a57: errata workaround for 833471 was missing!
  ...
  VERBOSE: BL31: cortex_a53: errata workaround for 826319 was not applied
  INFO:    BL31: cortex_a53: errata workaround for disable_non_temporal_hint was applied

Also update documentation.

Change-Id: Iccf059d3348adb876ca121cdf5207bdbbacf2aba
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Before adding a base address and a size to compute the end
address of an image to copy or authenticate, check this
won't result in an integer overflow. If it does then consider
the input arguments are invalid.

As a result, bl1_plat_mem_check() can now safely assume the
end address (computed as the sum of the base address and size
of the memory region) doesn't overflow, as the validation is
done upfront in bl1_fwu_image_copy/auth(). A debug assertion
has been added nonetheless in the ARM implementation in order
to help catching such problems, should bl1_plat_mem_check()
be called in a different context in the future.

Fixes TFV-1: Malformed Firmware Update SMC can result in copy
of unexpectedly large data into secure memory

Change-Id: I8b8f8dd4c8777705722c7bd0e8b57addcba07e25
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Signed-off-by: Dan Handley <dan.handley@arm.com>

These debug assertions sanity check the state of the internal
FWU state machine data when resuming an incomplete image copy
operation.

Change-Id: I38a125b0073658c3e2b4b1bdc623ec221741f43e
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

This patch refactors the code of the function handling a FWU_AUTH_COPY
SMC in BL1. All input validation has been moved upfront so it is now
shared between the RESET and COPYING states.

Change-Id: I6a86576b9ce3243c401c2474fe06f06687a70e2f
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Signed-off-by: Dan Handley <dan.handley@arm.com>

This patch introduces no functional change, it just changes
the serial console output.

 - Improve accuracy of error messages by decoupling some
   error cases;

 - Improve comments;

 - Move declaration of 'mem_layout' local variable closer to
   where it is used and make it const;

 - Rename a local variable to clarify whether it is a source
   or a destination address (base_addr -> dest_addr).

Change-Id: I349fcf053e233f316310892211d49e35ef2c39d9
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Signed-off-by: Dan Handley <dan.handley@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>

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>

The Virtualization field in the ID_PFR1 register has only 2
valid values (0 or 1) but it was incorrectly checked against
unrelated value tied to the SPSR register instead.

This patch fixes the detection of virtualization support by
using the valid values in BL1 context management code.

Change-Id: If12592e343770e1da90f0f5fecf0a3376047ac29

This patch adds generic changes in BL1 to support AArch32 state.
New AArch32 specific assembly/C files are introduced and
some files are moved to AArch32/64 specific folders.
BL1 for AArch64 is refactored but functionally identical.
BL1 executes in Secure Monitor mode in AArch32 state.

NOTE: BL1 in AArch32 state ONLY handles BL1_RUN_IMAGE SMC.

Change-Id: I6e2296374c7efbf3cf2aa1a0ce8de0732d8c98a5

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 removes the tight loop that calls `plat_report_exception`
in unhandled exceptions in AArch64 state.
The new behaviour is to call the `plat_report_exception` only
once followed by call to `plat_panic_handler`.
This allows platforms to take platform-specific action when
there is an unhandled exception, instead of always spinning
in a tight loop.

Note: This is a subtle break in behaviour for platforms that
      expect `plat_report_exception` to be continuously executed
      when there is an unhandled exception.

Change-Id: Ie2453804b9b7caf9b010ee73e1a90eeb8384e4e8

This patch moves the macro SIZE_FROM_LOG2_WORDS() defined in
`arch.h` to `utils.h` as it is utility macro.

Change-Id: Ia8171a226978f053a1ee4037f80142c0a4d21430

This patch moves the PSCI services and BL31 frameworks like context
management and per-cpu data into new library components `PSCI` and
`el3_runtime` respectively. This enables PSCI to be built independently from
BL31. A new `psci_lib.mk` makefile is introduced which adds the relevant
PSCI library sources and gets included by `bl31.mk`. Other changes which
are done as part of this patch are:

* The runtime services framework is now moved to the `common/` folder to
  enable reuse.
* The `asm_macros.S` and `assert_macros.S` helpers are moved to architecture
  specific folder.
* The `plat_psci_common.c` is moved from the `plat/common/aarch64/` folder
  to `plat/common` folder. The original file location now has a stub which
  just includes the file from new location to maintain platform compatibility.

Most of the changes wouldn't affect platform builds as they just involve
changes to the generic bl1.mk and bl31.mk makefiles.

NOTE: THE `plat_psci_common.c` FILE HAS MOVED LOCATION AND THE STUB FILE AT
THE ORIGINAL LOCATION IS NOW DEPRECATED. PLATFORMS SHOULD MODIFY THEIR
MAKEFILES TO INCLUDE THE FILE FROM THE NEW LOCATION.

Change-Id: I6bd87d5b59424995c6a65ef8076d4fda91ad5e86

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 a new linker symbol in BL1's linker script named
'__BL1_ROM_END__', which marks the end of BL1's ROM content. This
covers BL1's code, read-only data and read-write data to relocate
in Trusted SRAM. The address of this new linker symbol is exported
to C code through the 'BL1_ROM_END' macro.

The section related to linker symbols in the Firmware Design guide
has been updated and improved.

Change-Id: I5c442ff497c78d865ffba1d7d044511c134e11c7

The system registers that are saved and restored in CPU context include
AArch32 systems registers like SPSR_ABT, SPSR_UND, SPSR_IRQ, SPSR_FIQ,
DACR32_EL2, IFSR32_EL2 and FPEXC32_EL2. Accessing these registers on an
AArch64-only (i.e. on hardware that does not implement AArch32, or at
least not at EL1 and higher ELs) platform leads to an exception. This patch
introduces the build option `CTX_INCLUDE_AARCH32_REGS` to specify whether to
include these AArch32 systems registers in the cpu context or not. By default
this build option is set to 1 to ensure compatibility. AArch64-only platforms
must set it to 0. A runtime check is added in BL1 and BL31 cold boot path to
verify this.

Fixes ARM-software/tf-issues#386

Change-Id: I720cdbd7ed7f7d8516635a2ec80d025f478b95ee

This patch introduces some assembler macros to simplify the
declaration of the exception vectors. It abstracts the section
the exception code is put into as well as the alignments
constraints mandated by the ARMv8 architecture. For all TF images,
the exception code has been updated to make use of these macros.

This patch also updates some invalid comments in the exception
vector code.

Change-Id: I35737b8f1c8c24b6da89b0a954c8152a4096fa95

Asynchronous abort exceptions generated by the platform during cold boot are
not taken in EL3 unless SCR_EL3.EA is set.

Therefore EA bit is set along with RES1 bits in early BL1 and BL31 architecture
initialisation. Further write accesses to SCR_EL3 preserve these bits during
cold boot.

A build flag controls SCR_EL3.EA value to keep asynchronous abort exceptions
being trapped by EL3 after cold boot or not.

For further reference SError Interrupts are also known as asynchronous external
aborts.

On Cortex-A53 revisions below r0p2, asynchronous abort exceptions are taken in
EL3 whatever the SCR_EL3.EA value is.

Fixes arm-software/tf-issues#368
Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

This patch fixes inconsistencies in bl1_tbbr_image_descs[]
and miscellaneous fixes in Firmware Update code.

Following are the changes:
* As part of the original FWU changes, a `copied_size`
  field was added to `image_info_t`. This was a subtle binary
  compatibility break because it changed the size of the
  `bl31_params_t` struct, which could cause problems if
  somebody used different versions of BL2 or BL31, one with
  the old `image_info_t` and one with the new version.
  This patch put the `copied_size` within the `image_desc_t`.
* EXECUTABLE flag is now stored in `ep_info.h.attr` in place
  of `image_info.h.attr`, associating it to an entrypoint.
* The `image_info.image_base` is only relevant for secure
  images that are copied from non-secure memory into secure
  memory. This patch removes initializing `image_base` for
  non secure images in the bl1_tbbr_image_descs[].
* A new macro `SET_STATIC_PARAM_HEAD` is added for populating
  bl1_tbbr_image_descs[].ep_info/image_info.h members statically.
  The version, image_type and image attributes are now
  populated using this new macro.
* Added PLAT_ARM_NVM_BASE and PLAT_ARM_NVM_SIZE to avoid direct
  usage of V2M_FLASH0_XXX in plat/arm/common/arm_bl1_fwu.c.
* Refactoring of code/macros related to SECURE and EXECUTABLE flags.

NOTE: PLATFORM PORTS THAT RELY ON THE SIZE OF `image_info_t`
      OR USE the "EXECUTABLE" BIT WITHIN `image_info_t.h.attr`
      OR USE THEIR OWN `image_desc_t` ARRAY IN BL1, MAY BE
      BROKEN BY THIS CHANGE. THIS IS CONSIDERED UNLIKELY.

Change-Id: Id4e5989af7bf0ed263d19d3751939da1169b561d

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

The current implementation of FWU_SMC_IMAGE_RESUME when called
from the normal world, uses the provided image_id argument to
determine which secure image to resume into. This implies that
the normal world has a choice of which secure image to resume
into when in fact it is only possible to resume into the
previously interrupted secure image.

This patch removes the argument, tightens up the pre-conditions
for the SMC and adds additional asserts.

The pre-conditions for FWU_SMC_SEC_IMAGE_DONE are also
tightened up.

Change-Id: Ia5a46753bb01e8f8dad8a2999314f90db8f300e8

The implementation of FWU_SMC_IMAGE_AUTH performs a number of
pre-condition checks before authenticating the image. One of
these checks calls `bl1_plat_mem_check()` to ensure the image
source is mapped in when authenticating an image in place.
The framework incorrectly passes the security state of the
caller into this function instead of the security state of
the source image.

This patch corrects the defect. The defect would only
manifest itself for secure world callers authenticating
non-secure images in place, which is not done by current
upstream platforms.

Change-Id: I617c7b43e02ac7149f266aeaf3874316e62f3003

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

Firmware update(a.k.a FWU) feature is part of the TBB architecture.
BL1 is responsible for carrying out the FWU process if platform
specific code detects that it is needed.

This patch adds support for FWU feature support in BL1 which is
included by enabling `TRUSTED_BOARD_BOOT` compile time flag.

This patch adds bl1_fwu.c which contains all the core operations
of FWU, which are; SMC handler, image copy, authentication, execution
and resumption. It also adds bl1.h introducing #defines for all
BL1 SMCs.

Following platform porting functions are introduced:

int bl1_plat_mem_check(uintptr_t mem_base, unsigned int mem_size,
unsigned int flags);
	This function can be used to add platform specific memory checks
	for the provided base/size for the given security state.
	The weak definition will invoke `assert()` and return -ENOMEM.

__dead2 void bl1_plat_fwu_done(void *cookie, void *reserved);
	This function can be used to initiate platform specific procedure
	to mark completion of the FWU process.
	The weak definition waits forever calling `wfi()`.

plat_bl1_common.c contains weak definitions for above functions.

FWU process starts when platform detects it and return the image_id
other than BL2_IMAGE_ID by using `bl1_plat_get_next_image_id()` in
`bl1_main()`.

NOTE: User MUST provide platform specific real definition for
bl1_plat_mem_check() in order to use it for Firmware update.

Change-Id: Ice189a0885d9722d9e1dd03f76cac1aceb0e25ed

As of now BL1 loads and execute BL2 based on hard coded information
provided in BL1. But due to addition of support for upcoming Firmware
Update feature, BL1 now require more flexible approach to load and
run different images using information provided by the platform.

This patch adds new mechanism to load and execute images based on
platform provided image id's. BL1 now queries the platform to fetch
the image id of the next image to be loaded and executed. In order
to achieve this, a new struct image_desc_t was added which holds the
information about images, such as: ep_info and image_info.

This patch introduces following platform porting functions:

unsigned int bl1_plat_get_next_image_id(void);
	This is used to identify the next image to be loaded
	and executed by BL1.

struct image_desc *bl1_plat_get_image_desc(unsigned int image_id);
	This is used to retrieve the image_desc for given image_id.

void bl1_plat_set_ep_info(unsigned int image_id,
struct entry_point_info *ep_info);
	This function allows platforms to update ep_info for given
	image_id.

The plat_bl1_common.c file provides default weak implementations of
all above functions, the `bl1_plat_get_image_desc()` always return
BL2 image descriptor, the `bl1_plat_get_next_image_id()` always return
BL2 image ID and `bl1_plat_set_ep_info()` is empty and just returns.
These functions gets compiled into all BL1 platforms by default.

Platform setup in BL1, using `bl1_platform_setup()`, is now done
_after_ the initialization of authentication module. This change
provides the opportunity to use authentication while doing the
platform setup in BL1.

In order to store secure/non-secure context, BL31 uses percpu_data[]
to store context pointer for each core. In case of BL1 only the
primary CPU will be active hence percpu_data[] is not required to
store the context pointer.

This patch introduce bl1_cpu_context[] and bl1_cpu_context_ptr[] to
store the context and context pointers respectively. It also also
re-defines cm_get_context() and cm_set_context() for BL1 in
bl1/bl1_context_mgmt.c.

BL1 now follows the BL31 pattern of using SP_EL0 for the C runtime
environment, to support resuming execution from a previously saved
context.

NOTE: THE `bl1_plat_set_bl2_ep_info()` PLATFORM PORTING FUNCTION IS
      NO LONGER CALLED BY BL1 COMMON CODE. PLATFORMS THAT OVERRIDE
      THIS FUNCTION MAY NEED TO IMPLEMENT `bl1_plat_set_ep_info()`
      INSTEAD TO MAINTAIN EXISTING BEHAVIOUR.

Change-Id: Ieee4c124b951c2e9bc1c1013fa2073221195d881

The upcoming Firmware Update feature needs transitioning across
Secure/Normal worlds to complete the FWU process and hence requires
context management code to perform this task.

Currently context management code is part of BL31 stage only.
This patch moves the code from (include)/bl31 to (include)/common.
Some function declarations/definitions and macros have also moved
to different files to help code sharing.

Change-Id: I3858b08aecdb76d390765ab2b099f457873f7b0c

The primary usage of `RUN_IMAGE` SMC function id, used by BL2 is to
make a request to BL1 to execute BL31. But BL2 also uses it as
opcode to check if it is allowed to execute which is not the
intended usage of `RUN_IMAGE` SMC.

This patch removes the usage of `RUN_IMAGE` as opcode passed to
next EL to check if it is allowed to execute.

Change-Id: I6aebe0415ade3f43401a4c8a323457f032673657

This patch introduces a new build option named COLD_BOOT_SINGLE_CPU,
which allows platforms that only release a single CPU out of reset to
slightly optimise their cold boot code, both in terms of code size
and performance.

COLD_BOOT_SINGLE_CPU defaults to 0, which assumes that the platform
may release several CPUs out of reset. In this case, the cold reset
code needs to coordinate all CPUs via the usual primary/secondary
CPU distinction.

If a platform guarantees that only a single CPU will ever be released
out of reset, there is no need to arbitrate execution ; the notion of
primary and secondary CPUs itself no longer exists. Such platforms
may set COLD_BOOT_SINGLE_CPU to 1 in order to compile out the
primary/secondary CPU identification in the cold reset code.

All ARM standard platforms can release several CPUs out of reset
so they use COLD_BOOT_SINGLE_CPU=0. However, on CSS platforms like
Juno, bringing up more than one CPU at reset should only be attempted
when booting an EL3 payload, as it is not fully supported in the
normal boot flow.

For platforms using COLD_BOOT_SINGLE_CPU=1, the following 2 platform
APIs become optional:
  - plat_secondary_cold_boot_setup();
  - plat_is_my_cpu_primary().
The Porting Guide has been updated to reflect that.

User Guide updated as well.

Change-Id: Ic5b474e61b7aec1377d1e0b6925d17dfc376c46b

This patch modifies the prototype of the bl1_plat_prepare_exit()
platform API to pass the address of the entry point info structure
received from BL2. The structure contains information that can be
useful, depending on the kind of clean up or bookkeeping operations
to perform.

The weak implementation of this function ignores this argument to
preserve platform backwards compatibility.

NOTE: THIS PATCH MAY BREAK PLATFORM PORTS THAT ARE RELYING ON THE
FORMER PROTOTYPE OF THE BL1_PLAT_PREPARE_EXIT() API.

Change-Id: I3fc18f637de06c85719c4ee84c85d6a4572a0fdb

This patch introduces a new build flag, SPIN_ON_BL1_EXIT, which
puts an infinite loop in BL1. It is intended to help debugging
the post-BL2 phase of the Trusted Firmware by stopping execution
in BL1 just before handing over to BL31. At this point, the
developer may take control of the target using a debugger.

This feature is disabled by default and can be enabled by
rebuilding BL1 with SPIN_ON_BL1_EXIT=1.

User Guide updated accordingly.

Change-Id: I6b6779d5949c9e5571dd371255520ef1ac39685c

 - Remove out-dated information about the use of printf() in the
   function comment.

 - Make the argument const, as the function doesn't need to modify it.

 - Rename the function into bl1_print_bl31_ep_info() to make its
   purpose clearer.

Change-Id: I2a9d215a37f0ec11aefce0c5c9e050473b7a6b25

This patch introduces a new function called 'print_entry_point_info'
that prints an entry_point_t structure for debugging purposes.
As such, it can be used to display the entry point address, SPSR and
arguments passed from a firmware image to the next one.

This function is now called in the following images transitions:
 - BL1 to BL2
 - BL1 to BL31
 - BL31 to the next image (typically BL32 or BL33)

The following changes have been introduced:

 - Fix the output format of the SPSR value : SPSR is a 32-bit value,
   not a 64-bit one.

 - Print all arguments values.
   The entry_point_info_t structure allows to pass up to 8 arguments.
   In most cases, only the first 2 arguments were printed.
   print_entry_point_info() now prints all of them as 'VERBOSE'
   traces.

Change-Id: Ieb384bffaa7849e6cb95a01a47c0b7fc2308653a

This patch adds an optional API to the platform port:

    void plat_error_handler(int err) __dead2;

The platform error handler is called when there is a specific error
condition after which Trusted Firmware cannot continue. While panic()
simply prints the crash report (if enabled) and spins, the platform
error handler can be used to hand control over to the platform port
so it can perform specific bookeeping or post-error actions (for
example, reset the system). This function must not return.

The parameter indicates the type of error using standard codes from
errno.h. Possible errors reported by the generic code are:

    -EAUTH  : a certificate or image could not be authenticated
              (when Trusted Board Boot is enabled)
    -ENOENT : the requested image or certificate could not be found
              or an IO error was detected
    -ENOMEM : resources exhausted. Trusted Firmware does not use
              dynamic memory, so this error is usually an indication
              of an incorrect array size

A default weak implementation of this function has been provided.
It simply implements an infinite loop.

Change-Id: Iffaf9eee82d037da6caa43b3aed51df555e597a3

This patch adds an optional API to the platform port:

    void bl1_plat_prepare_exit(void);

This function is called prior to exiting BL1 in response to the
RUN_IMAGE_SMC request raised by BL2. It should be used to perform
platform specific clean up or bookkeeping operations before
transferring control to the next image.

A weak empty definition of this function has been provided to
preserve platform backwards compatibility.

Change-Id: Iec09697de5c449ae84601403795cdb6aca166ba1

The AArch64 synchronous exception vector code in BL1 is almost
reaching its architectural limit of 32 instructions. This means
there is very little space for this code to grow.

This patch reduces the size of the exception vector code by
moving most of its code in a function to which we branch from
SynchronousExceptionA64.

Change-Id: Ib35351767a685fb2c2398029d32e54026194f7ed