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The translation tables allocated for the Secure Partition do not need
to be treated as a special case. They can be put amongst the other
tables mapping BL31's general purpose memory. They will be mapped with
the same attributes as them, which is fine.

The explicit alignment constraint in BL31's linker script to pad the
last page of memory allocated to the Secure Partition's translation
tables is useless too, as page tables are per se pages, thus their
end address is naturally aligned on a page-boundary.

In fact, this patch does not change the existing behaviour. Since
patch 22282bb6

 ("SPM: Move all SP-related info to SP context
struct"), the secure_partition.c file has been renamed into sp_xlat.c
but the linker script has not been properly updated. As a result, the
SP translation tables are not specifically put at the start of the
xlat_table linker section, the __SP_IMAGE_XLAT_TABLES_START__/_END__
symbols have the same value, the size of the resulting mmap_region
covering these xlat tables is 0 and so it is ignored.

Change-Id: I4cf0a4cc090298811cca53fc9cee74df0f2b1512
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

Move all information related to a Secure Partition to the struct
secure_partition_context_t.

This requires an in-depth refactor because most of the previous code of
SPM relied on global information.

Change-Id: I0a23e93817dcc191ce1d7506b8bc671d376123c4
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Void pointers have been used to access linker symbols, by declaring an
extern pointer, then taking the address of it. This limits symbols
values to aligned pointer values. To remove this restriction an
IMPORT_SYM macro has been introduced, which declares it as a char
pointer and casts it to the required type.

Change-Id: I89877fc3b13ed311817bb8ba79d4872b89bfd3b0
Signed-off-by: Joel Hutton <Joel.Hutton@Arm.com>

The secure_partition_boot_info_t structure is used to communicate boot
parameters with the StandaloneMM code executing at S-EL0 through a
shared buffer. Certain data types used for members of this structure
are opaque with their size depending on the toolchain being used.

Declare the members of the structure with explicit width based data
types, which would maintain compatibility across toolchains.
Signed-off-by: Sughosh Ganu <sughosh.ganu@arm.com>

A Secure Partition is a software execution environment instantiated in
S-EL0 that can be used to implement simple management and security
services. Since S-EL0 is an unprivileged exception level, a Secure
Partition relies on privileged firmware e.g. ARM Trusted Firmware to be
granted access to system and processor resources. Essentially, it is a
software sandbox that runs under the control of privileged software in
the Secure World and accesses the following system resources:

- Memory and device regions in the system address map.
- PE system registers.
- A range of asynchronous exceptions e.g. interrupts.
- A range of synchronous exceptions e.g. SMC function identifiers.

A Secure Partition enables privileged firmware to implement only the
absolutely essential secure services in EL3 and instantiate the rest in
a partition. Since the partition executes in S-EL0, its implementation
cannot be overly complex.

The component in ARM Trusted Firmware responsible for managing a Secure
Partition is called the Secure Partition Manager (SPM). The SPM is
responsible for the following:

- Validating and allocating resources requested by a Secure Partition.
- Implementing a well defined interface that is used for initialising a
  Secure Partition.
- Implementing a well defined interface that is used by the normal world
  and other secure services for accessing the services exported by a
  Secure Partition.
- Implementing a well defined interface that is used by a Secure
  Partition to fulfil service requests.
- Instantiating the software execution environment required by a Secure
  Partition to fulfil a service request.

Change-Id: I6f7862d6bba8732db5b73f54e789d717a35e802f
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Achin Gupta <achin.gupta@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>