Sanitise includes across codebase ...

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: e0ea0928d5b7 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a282 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca33988b9 ("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>

psci: platform control of SYSTEM_SUSPEND entry ...

Some platforms can only resume from system suspend from the boot
CPU, hence they should only enter that state from that same core.

The following commit presents an interface that allows the platform to
reject system suspend entry near its very last stage (last CPU).

psci: Use bool in internal interfaces ...

Change-Id: I77c9cd2d1d6d0122cc49917fa686014bee154589
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

PSCI: Fix MISRA defects in common and setup code ...

MISRA C-2012 Rules 10.1, 10.3, 17.8 and 20.7.

Change-Id: I3980bd2a1d845559af4bbe2887a0250d0506a064
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

lib: fix switch statements to comply with MISRA rules ...

Ensure (where possible) that switch statements in lib comply with MISRA
rules 16.1 - 16.7.

Change-Id: I52bc896fb7094d2b7569285686ee89f39f1ddd84
Signed-off-by: Jonathan Wright <jonathan.wright@arm.com>

Rename 'smcc' to 'smccc' ...

When the source code says 'SMCC' it is talking about the SMC Calling
Convention. The correct acronym is SMCCC. This affects a few definitions
and file names.

Some files have been renamed (smcc.h, smcc_helpers.h and smcc_macros.S)
but the old files have been kept for compatibility, they include the
new ones with an ERROR_DEPRECATED guard.

Change-Id: I78f94052a502436fdd97ca32c0fe86bd58173f2f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Add support for SMCCC_VERSION in PSCI features ...

On some platforms it may be necessary to discover the SMCCC version
via a PSCI features call.

Change-Id: I95281ac2263ca9aefda1809eb03464fbdb8ac24d
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Flush the affinity data in psci_affinity_info ...

There is an edge case where the cache maintaince done in
psci_do_cpu_off may not seen by some cores. This case is handled in
psci_cpu_on_start but it hasn't handled in psci_affinity_info.

Change-Id: I4d64f3d1ca9528e364aea8d04e2d254f201e1702
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

reset2: Add PSCI system_reset2 function ...

This patch implements PSCI_SYSTEM_RESET2 API as defined in PSCI
v1.1 specification. The specification allows architectural and
vendor-specific resets via this API. In the current specification,
there is only one architectural reset, the warm reset. This reset is
intended to provide a fast reboot path that guarantees not to reset
system main memory.

Change-Id: I057bb81a60cd0fe56465dbb5791d8e1cca025bd3
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

mem_protect: Add mem_protect API ...

This patch adds the generic code that links the psci smc handler
with the platform function that implements the mem_protect and
mem_check_range functionalities. These functions are  optional
APIs added in PSCI v1.1 (ARM DEN022D).

Change-Id: I3bac1307a5ce2c7a196ace76db8317e8d8c8bb3f
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Tegra: enable 'signed-comparison' compilation warning/errors ...

This patch enables the 'sign-compare' flag, to enable warning/errors
for comparisons between signed/unsigned variables. The warning has
been enabled for all the Tegra platforms, to start with.

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

Use SPDX license identifiers ...

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>

PSCI: Decouple PSCI stat residency calculation from PMF ...

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>

Add PMF instrumentation points in TF ...

In order to quantify the overall time spent in the PSCI software
implementation, an initial collection of PMF instrumentation points
has been added.

Instrumentation has been added to the following code paths:

- Entry to PSCI SMC handler.  The timestamp is captured as early
  as possible during the runtime exception and stored in memory
  before entering the PSCI SMC handler.

- Exit from PSCI SMC handler.  The timestamp is captured after
  normal return from the PSCI SMC handler or if a low power state
  was requested it is captured in the bl31 warm boot path before
  return to normal world.

- Entry to low power state.  The timestamp is captured before entry
  to a low power state which implies either standby or power down.
  As these power states are mutually exclusive, only one timestamp
  is defined to describe both.  It is possible to differentiate between
  the two power states using the PSCI STAT interface.

- Exit from low power state.  The timestamp is captured after a standby
  or power up operation has completed.

To calculate the number of cycles spent running code in Trusted Firmware
one can perform the following calculation:

(exit_psci - enter_psci) - (exit_low_pwr - enter_low_pwr).

The resulting number of cycles can be converted to time given the
frequency of the counter.

Change-Id: Ie3b8f3d16409b6703747093b3a2d5c7429ad0166
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

PSCI: Add support for PSCI NODE_HW_STATE API ...

This patch adds support for NODE_HW_STATE PSCI API by introducing a new
PSCI platform hook (get_node_hw_state). The implementation validates
supplied arguments, and then invokes this platform-defined hook and
returns its result to the caller. PSCI capabilities are updated
accordingly.

Also updates porting and firmware design guides.

Change-Id: I808e55bdf0c157002a7c104b875779fe50a68a30

Validate psci_find_target_suspend_lvl() result ...

This patch adds a runtime check that psci_find_target_suspend_lvl()
returns a valid value back to psci_cpu_suspend() and psci_get_stat().
If it is invalid, BL31 will now panic.

Note that on the PSCI CPU suspend path there is already a debug
assertion checking the validity of the target composite power state,
which effectively also checks the validity of the target suspend level.
Therefore, the error condition would already be caught in debug builds,
but in a release build this assertion would be compiled out.

On the PSCI stat path, there is currently no debug assertion checking
the validity of the power state before using it as an index into
the power domain state array.

Although BL31 platforms ports are responsible for validating the
power state parameter, the security impact (i.e. an out-of-bounds
array access) of a potential platform port bug in this code would
be quite high, given that this parameter comes from an untrusted
source. The cost of checking this in runtime generic code is low.

Change-Id: Icea85b8020e39928ac03ec0cd49805b5857b3906

Introduce PSCI Library Interface ...

This patch introduces the PSCI Library interface. The major changes
introduced are as follows:

* Earlier BL31 was responsible for Architectural initialization during cold
boot via bl31_arch_setup() whereas PSCI was responsible for the same during
warm boot. This functionality is now consolidated by the PSCI library
and it does Architectural initialization via psci_arch_setup() during both
cold and warm boots.

* Earlier the warm boot entry point was always `psci_entrypoint()`. This was
not flexible enough as a library interface. Now PSCI expects the runtime
firmware to provide the entry point via `psci_setup()`. A new function
`bl31_warm_entrypoint` is introduced in BL31 and the previous
`psci_entrypoint()` is deprecated.

* The `smc_helpers.h` is reorganized to separate the SMC Calling Convention
defines from the Trusted Firmware SMC helpers. The former is now in a new
header file `smcc.h` and the SMC helpers are moved to Architecture specific
header.

* The CPU context is used by PSCI for context initialization and
restoration after power down (PSCI Context). It is also used by BL31 for SMC
handling and context management during Normal-Secure world switch (SMC
Context). The `psci_smc_handler()` interface is redefined to not use SMC
helper macros thus enabling to decouple the PSCI context from EL3 runtime
firmware SMC context. This enables PSCI to be integrated with other runtime
firmware using a different SMC context.

NOTE: With this patch the architectural setup done in `bl31_arch_setup()`
is done as part of `psci_setup()` and hence `bl31_platform_setup()` will be
invoked prior to architectural setup. It is highly unlikely that the platform
setup will depend on architectural setup and cause any failure. Please be
be aware of this change in sequence.

Change-Id: I7f497a08d33be234bbb822c28146250cb20dab73

Introduce `el3_runtime` and `PSCI` libraries ...

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