Cleanup FIP build targets and messages ...

At present the fip.bin depends on phony targets for BL images, resulting
in unconditional remake of fip.bin. Also the build messages doesn't
match with the rest of build system.

This patch modifies the fip.bin dependencies to the actual BL binary
images so that fip.bin is remade only when the component images are
rebuilt/modified. The build messages and FIP Makefile are modified to
match the style of rest of the build system.

Change-Id: I8dd08666ff766d106820a5b4b037c2161bcf140f

Report recoverable errors as warnings ...

At present many recoverable failures are reported as errors. This patch
modifies all such failures to be reported as warnings instead.

Change-Id: I5141653c82498defcada9b90fdf7498ba496b2f2

Rework arithmetic operations in Test Secure Payload ...

This patch reworks the service provided by the TSP to perform common
arithmetic operations on a set of arguments provided by the non-secure
world. For a addition, division, subtraction & multiplication operation
requested on two arguments in x0 and x1 the steps are:

1. TSPD saves the non-secure context and passes the operation and its
   arguments to the TSP.

2. TSP asks the TSPD to return the same arguments once again. This
   exercises an additional SMC path.

3. TSP now has two copies of both x0 and x1. It performs the operation
   on the corresponding copies i.e. in case of addition it returns x0+x0
   and x1+x1.

4. TSPD receives the result, saves the secure context, restores the
   non-secure context and passes the result back to the non-secure
   client.

Change-Id: I6eebfa2ae0a6f28b1d2e11a31f575c7a4b96724b
Co-authored-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Add power management support in the SPD ...

This patch implements a set of handlers in the SPD which are called by
the PSCI runtime service upon receiving a power management
operation. These handlers in turn pass control to the Secure Payload
image if required before returning control to PSCI. This ensures that
the Secure Payload has complete visibility of all power transitions in
the system and can prepare accordingly.

Change-Id: I2d1dba5629b7cf2d53999d39fe807dfcf3f62fe2

Add Test Secure Payload Dispatcher (TSPD) service ...

This patch adds the TSPD service which is responsible for managing
communication between the non-secure state and the Test Secure Payload
(TSP) executing in S-EL1.

The TSPD does the following:

1. Determines the location of the TSP (BL3-2) image and passes control
   to it for initialization. This is done by exporting the 'bl32_init()'
   function.

2. Receives a structure containing the various entry points into the TSP
   image as a response to being initialized. The TSPD uses this
   information to determine how the TSP should be entered depending on
   the type of operation.

3. Implements a synchronous mechanism for entering into and returning
   from the TSP image. This mechanism saves the current C runtime
   context on top of the current stack and jumps to the TSP through an
   ERET instruction. The TSP issues an SMC to indicate completion of the
   previous request. The TSPD restores the saved C runtime context and
   resumes TSP execution.

This patch also introduces a Make variable 'SPD' to choose the specific
SPD to include in the build. By default, no SPDs are included in the
build.

Change-Id: I124da5695cdc510999b859a1bf007f4d049e04f3
Co-authored-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Fix FIP offset address when file not found ...

If there is a request to open a file from FIP, and that file is not
found, the driver fails to reset the offset address. This causes
subsequent file loads to fail.

This patch resets the offset address to zero if a file is not found so
that subsequent file loads are unaffected.

Change-Id: I16418e35f92fb7c85fb12e2acc071990520cdef8

Add Test Secure Payload (BL3-2) image ...

This patch adds a simple TSP as the BL3-2 image. The secure payload
executes in S-EL1. It paves the way for the addition of the TSP
dispatcher runtime service to BL3-1. The TSP and the dispatcher service
will serve as an example of the runtime firmware's ability to toggle
execution between the non-secure and secure states in response to SMC
request from the non-secure state.  The TSP will be replaced by a
Trusted OS in a real system.

The TSP also exports a set of handlers which should be called in
response to a PSCI power management event e.g a cpu being suspended or
turned off. For now it runs out of Secure DRAM on the ARM FVP port and
will be moved to Secure SRAM later. The default translation table setup
code assumes that the caller is executing out of secure SRAM. Hence the
TSP exports its own translation table setup function.

The TSP only services Fast SMCs, is non-reentrant and non-interruptible.
It does arithmetic operations on two sets of four operands, one set
supplied by the non-secure client, and the other supplied by the TSP
dispatcher in EL3. It returns the result according to the Secure Monitor
Calling convention standard.

This TSP has two functional entry points:

- An initial, one-time entry point through which the TSP is initialized
  and prepares for receiving further requests from secure
  monitor/dispatcher

- A fast SMC service entry point through which the TSP dispatcher
  requests secure services on behalf of the non-secure client

Change-Id: I24377df53399307e2560a025eb2c82ce98ab3931
Co-authored-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Move PSCI to runtime services directory ...

This patch creates a 'services' directory and moves the PSCI under
it. Other runtime services e.g. the Secure Payload Dispatcher service
will be placed under the same directory in the future.

Also fixes issue ARM-software/tf-issues#12

Change-Id: I187f83dcb660b728f82155d91882e961d2255068

Specify address of UART device to use as a console ...

This patch adds the ability to specify the base address of a UART
device for initialising the console. This allows a boot loader stage
to use a different UART device from UART0 (default) for the console.

Change-Id: Ie60b927389ae26085cfc90d22a564ff83ba62955

Factor out translation table setup in ARM FVP port ...

This patch factors out the ARM FVP specific code to create MMU
translation tables so that it is possible for a boot loader stage to
create a different set of tables instead of using the default ones.
The default translation tables are created with the assumption that
the calling boot loader stage executes out of secure SRAM. This might
not be true for the BL3_2 stage in the future.

A boot loader stage can define the `fill_xlation_tables()` function as
per its requirements. It returns a reference to the level 1
translation table which is used by the common platform code to setup
the TTBR_EL3.

This patch is a temporary solution before a larger rework of
translation table creation logic is introduced.

Change-Id: I09a075d5da16822ee32a411a9dbe284718fb4ff6

Add support for BL3-2 in BL3-1 ...

This patch adds the following support to the BL3-1 stage:

1. BL3-1 allows runtime services to specify and determine the security
   state of the next image after BL3-1. This has been done by adding
   the `bl31_set_next_image_type()` & `bl31_get_next_image_type()`
   apis. The default security state is non-secure. The platform api
   `bl31_get_next_image_info()` has been modified to let the platform
   decide which is the next image in the desired security state.

2. BL3-1 exports the `bl31_prepare_next_image_entry()` function to
   program entry into the target security state. It uses the apis
   introduced in 1. to do so.

3. BL3-1 reads the information populated by BL2 about the BL3-2 image
   into its internal data structures.

4. BL3-1 introduces a weakly defined reference `bl32_init()` to allow
   initialisation of a BL3-2 image. A runtime service like the Secure
   payload dispatcher will define this function if present.

Change-Id: Icc46dcdb9e475ce6575dd3f9a5dc7a48a83d21d1

Add support for BL3-2 in BL2 ...

This patch adds support for loading a BL3-2 image in BL2. In case a
BL3-2 image is found, it also passes information to BL3-1 about where it
is located and the extents of memory available to it. Information about
memory extents is populated by platform specific code.

The documentation has also been updated to reflect the above changes.

Change-Id: I526b2efb80babebab1318f2b02e319a86d6758b0
Co-authored-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Rework BL2 to BL3-1 hand over interface ...

This patch reworks BL2 to BL3-1 hand over interface by introducing a
composite structure (bl31_args) that holds the superset of information
that needs to be passed from BL2 to BL3-1.

  - The extents of secure memory available to BL3-1
  - The extents of memory available to BL3-2 (not yet implemented) and
    BL3-3
  - Information to execute BL3-2 (not yet implemented) and BL3-3 images

This patch also introduces a new platform API (bl2_get_bl31_args_ptr)
that needs to be implemented by the platform code to export reference to
bl31_args structure which has been allocated in platform-defined memory.

The platform will initialize the extents of memory available to BL3-3
during early platform setup in bl31_args structure. This obviates the
need for bl2_get_ns_mem_layout platform API.

BL2 calls the bl2_get_bl31_args_ptr function to get a reference to
bl31_args structure. It uses the 'bl33_meminfo' field of this structure
to load the BL3-3 image. It sets the entry point information for the
BL3-3 image in the 'bl33_image_info' field of this structure. The
reference to this structure is passed to the BL3-1 image.

Also fixes issue ARM-software/tf-issues#25

Change-Id: Ic36426196dd5ebf89e60ff42643bed01b3500517

Add exception vector guards ...

This patch adds guards so that an exception vector exceeding 32
instructions will generate a compile-time error. This keeps the
exception handlers in check from spilling over.

Change-Id: I7aa56dd0071a333664e2814c656d3896032046fe

Increase coherent stack sizes ...

This patch increases coherent stack size for both debug and release
builds in order to accommodate stack-heavy printf() and extended EL3
functionality

Change-Id: I30ef30530a01517a97e63d703873374828c09f20

Add support for handling runtime service requests ...

This patch uses the reworked exception handling support to handle
runtime service requests through SMCs following the SMC calling
convention. This is a giant commit since all the changes are
inter-related. It does the following:

1. Replace the old exception handling mechanism with the new one
2. Enforce that SP_EL0 is used C runtime stacks.
3. Ensures that the cold and warm boot paths use the 'cpu_context'
   structure to program an ERET into the next lower EL.
4. Ensures that SP_EL3 always points to the next 'cpu_context'
   structure prior to an ERET into the next lower EL
5. Introduces a PSCI SMC handler which completes the use of PSCI as a
   runtime service

Change-Id: I661797f834c0803d2c674d20f504df1b04c2b852
Co-authored-by: Achin Gupta <achin.gupta@arm.com>

Introduce new exception handling framework ...

This patch introduces the reworked exception handling logic which lays
the foundation for accessing runtime services in later patches. The
type of an exception has a greater say in the way it is
handled. SP_EL3 is used as the stack pointer for:

1. Determining the type of exception and handling the unexpected ones
   on the exception stack

2. Saving and restoring the essential general purpose and system
   register state after exception entry and prior to exception exit.

SP_EL0 is used as the stack pointer for handling runtime service
requests e.g. SMCs. A new structure for preserving general purpose
register state has been added to the 'cpu_context' structure. All
assembler ensures that it does not use callee saved registers
(x19-x29). The C runtime preserves them across functions calls. Hence
EL3 code does not have to save and restore them explicitly.

Since the exception handling framework has undergone substantial change,
the changes have been kept in separate files to aid readability. These
files will replace the existing ones in subsequent patches.

Change-Id: Ice418686592990ff7a4260771e8d6676e6c8c5ef

Add runtime services framework ...

This patch introduces the framework to enable registration and
initialisation of runtime services. PSCI is registered and initialised
as a runtime service. Handling of runtime service requests will be
implemented in subsequent patches.

Change-Id: Id21e7ddc5a33d42b7d6e455b41155fc5441a9547

psci: Use context library for preserving EL3 state ...

This patch uses the context library to save and restore EL3 state on
the 'cpu_context' data structures allocated by PSCI for managing
non-secure state context on each cpu.

Change-Id: I19c1f26578204a7cd9e0a6c582ced0d97ee4cf80

Add context management library ...

This patch adds support for a cpu context management library. This
library will be used to:

1. Share pointers to secure and non-secure state cpu contexts between
   runtime services e.g. PSCI and Secure Payload Dispatcher services
2. Set SP_EL3 to a context structure which will be used for
   programming an ERET into a lower EL
3. Provide wrapper functions to save and restore EL3 & EL1
   state. These functions will in turn use the helper functions in
   context.S

Change-Id: I655eeef83dcd2a0c6f2eb2ac23efab866ac83ca0

Add helper library for cpu context management ...

This patch introduces functions for saving and restoring shared system
registers between secure and non-secure EL1 exception levels, VFP
registers and essential EL3 system register and other state. It also
defines the 'cpu_context' data structure which will used for saving and
restoring execution context for a given security state. These functions
will allow runtime services like PSCI and Secure payload dispatcher to
implement logic for switching between the secure and non-secure states.

The save and restore functions follow AArch64 PCS and only use
caller-saved temporary registers.

Change-Id: I8ee3aaa061d3caaedb28ae2c5becb9a206b6fd74

Setup VBAR_EL3 incrementally ...

This patch ensures that VBAR_EL3 points to the simple stack-less
'early_exceptions' when the C runtime stack is not correctly setup to
use the more complex 'runtime_exceptions'. It is initialised to
'runtime_exceptions' once this is done.

This patch also moves all exception vectors into a '.vectors' section
and modifies linker scripts to place all such sections together. This
will minimize space wastage from alignment restrictions.

Change-Id: I8c3e596ea3412c8bd582af9e8d622bb1cb2e049d

Fix spilled-over BL1 exception vector ...

The SynchronousExceptionA64 vector has gone beyond the 32-instruction
limit for individual exception vector. This patch splits and relocates
the exception handler so that it fits into the 32-instruction window.

Change-Id: Ic60c4fc3f09a1cb071d63ff0e58353ecaecbb62f

Move translation tables into separate section ...

This patch moves the translation tables into their own section. This
saves space that would otherwise have been lost in padding due to page
table alignment constraints. The BL31 and BL32 bases have been
consequently adjusted.

Change-Id: Ibd65ae8a5ce4c4ea9a71a794c95bbff40dc63e65

Add Firmware Image Package (FIP) documentation ...

This fixes ARM-software/tf-issues#9

Change-Id: Id57037115b8762efc9eaf5ff41887b71d6494c5d

Add Firmware Image Package (FIP) driver ...

The Firmware Image Package (FIP) driver allows for data to be loaded
from a FIP on platform storage. The FVP supports loading bootloader
images from a FIP located in NOR FLASH.

The implemented FVP policy states that bootloader images will be
loaded from a FIP in NOR FLASH if available and fall back to loading
individual images from semi-hosting.

NOTE:
- BL3-3(e.g. UEFI) is loaded into DRAM and needs to be configured
  to run from the BL33_BASE address. This is currently set to
  DRAM_BASE+128MB for the FVP.

Change-Id: I2e4821748e3376b5f9e467cf3ec09509e43579a0

Add Firmware Image Package creation tool ...

This tool can be used to create a Firmware Image Packages (FIP). These
FIPs store a combined set of firmware images with a Table of Contents
(ToC) that can be loaded by the firmware from platform storage.

- Add uuid.h from FreeBSD.
- Use symbolic links to shared headers otherwise unwanted headers and
  definitions are pulled in.
- A FIP is created as part of the default FVP build.
- A BL3-3 image(e.g. UEFI) must be provided.

Change-Id: Ib73feee181df2dba68bf6abec115a83cfa5e26cb

Implement load_image in terms of IO abstraction ...

The modified implementation uses the IO abstraction rather than
making direct semi-hosting calls.  The semi-hosting driver is now
registered for the FVP platform during initialisation of each boot
stage where it is used.  Additionally, the FVP platform includes a
straightforward implementation of 'plat_get_image_source' which
provides a generic means for the 'load_image' function to determine
how to access the image data.

Change-Id: Ia34457b471dbee990c7b3c79de7aee4ceea51aa6

Add IO abstraction framework ...

This is intended primarily for use as a storage abstraction.
It allows operations such as image-loading to be implemented
in a platform-independent fashion.  Each platform registers
a set of IO drivers during initialisation.  The platform must
also provide a function that will return a device and a specifier
that can be used to access specified content.

Clients of the API will primarily use device and entity handles.
The term "entity" is deliberately vague, to allow for different
representations of content accessed using different types of
specifier, but will often be interpreted as a "file" where the
specifier will normally be its path.

This commit builds, but is intended to be paired with a sample
implementation of "load_image" using a semi-hosting driver on FVP.

Change-Id: Id3b52f1c0eb9ce76b44b99fc6b6460803668cc86

Fix asserts appearing in release builds ...

Also fix warnings generated in release builds when assert code
is absent.

Change-Id: I45b9173d3888f9e93e98eb5b4fdc06727ba5cbf4