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>

Reorder log level macro definitions for clarity ...

The definitions of the logging macros are reordered to be consistent
with the definitions of the log levels.

Change-Id: I6ff07b93eb64786ff147d39014d1c8e15db28444
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

Fix MISRA defects in log helpers ...

No functional changes.

Change-Id: I850f08718abb69d5d58856b0e3de036266d8c2f4
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

backtrace: Print backtrace in assert() and panic() ...

When any of these functions is called the backtrace will be printed to
the console.

Change-Id: Id60842df824b320c485a9323ed6b80600f4ebe35
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

backtrace: Introduce backtrace function ...

This function diplays the backtrace, the current EL and security state
to allow a post-processing tool to choose the right binary to interpret
the dump.

The output can be fed to GNU addr2line to resolve function names given
an ELF binary compiled with debug information. The "-i" flag is
recommended to improve display in case of inlined functions. The *.dump
files generated during the build process can also be used.

The function works in AArch64 and AArch32. In AArch32 it only works in
A32 mode (without T32 interworking), which is enforced in the Makefile.

Sample output of a backtrace at EL3:

    BACKTRACE: START: function_name
    0: EL3: 0x798
    1: EL3: 0x538
    2: EL3: 0x550
    3: EL3: 0x55c
    4: EL3: 0x568
    5: EL3: 0x5a8
    6: EL3: 0xf4
    BACKTRACE: END: function_name

In order to enable it the new option ENABLE_BACKTRACE must be set to 1.
This option is set to 1 by default only in AArch64 debug builds. As
usual, it can be overridden by the platform makefile and in the build
command line.

Change-Id: Icaff39b0e5188329728be2f3c72b868b2368e794
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

libc: Move tf_printf and tf_snprintf to libc ...

Change their names to printf and snprintf. They are much smaller than
the previous versions we had, which makes them better suited for the
Trusted Firmware.

Change-Id: Ia872af91b7b967c47fce012eccecede7873a3daf
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

tf_printf: Return number of printed characters ...

The C standard says that printf() has to return the number of characters
it has printed.

Change-Id: I0ef50b1d6766d140724ac0a2fa2c5d023431f984
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

libc: Fix all includes in codebase ...

The codebase was using non-standard headers. It is needed to replace
them by the correct ones so that we can use the new libc headers.

Change-Id: I530f71d9510cb036e69fe79823c8230afe890b9d
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Run compiler on debug macros for type checking ...

Even if the log output is too low for a message to be printed out on
the console by the debug macros, it should still be evaluated by the
compiler to get some type checking and validation of the format
specifiers. To do so, introduce the no_tf_log() macro that encloses
the call to tf_log() in an always-false condition.

This avoids the problem of discovering build issues only when we build
the firmware with the right LOG_LEVEL value.

Change-Id: Ic0fd252ab691d0187fd925756a4837aca1cbfd7b
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

Implement log framework ...

This patch gives users control over logging messages printed from the C
code using the LOG macros defined in debug.h Users now have the ability
to reduce the log_level at run time using the tf_log_set_max_level()
function. The default prefix string can be defined by platform by
overriding the `plat_log_get_prefix()` platform API which is also
introduced in this patch.

The new log framework results in saving of some RO data. For example,
when BL1 is built for FVP with LOG_LEVEL=LOG_LEVEL_VERBOSE, resulted
in saving 384 bytes of RO data and increase of 8 bytes of RW data. The
framework also adds about 108 bytes of code to the release build of FVP.

Fixes ARM-software/tf-issues#462

Change-Id: I476013d9c3deedfdd4c8b0b0f125665ba6250554
Co-authored-by: Eleanor Bonnici <Eleanor.bonnici@arm.com>
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Introduce tf_vprintf() and tf_string_print() ...

This patch introduces tf_vprintf() and tf_string_print() APIs
which is needed by the logging framework introduced in a later
patch.

Change-Id: Ie4240443d0e04e070502b51e371e546dd469fd33
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Introduce `tf_snprintf` ...

This is a reduced version of `snprintf` that only supports formats '%d',
'%i' and '%u'. It can be used when the full `snprintf` is not needed in
order to save memory. If it finds an unknown format specifier, it
prints an error message and panics.

Change-Id: I2cb06fcdf74cda2c43caf73ae0762a91499fc04e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.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>

Add support for GCC stack protection ...

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>

Make cpu operations warning a VERBOSE print ...

The assembler helper function `print_revision_warning` is used when a
CPU specific operation is enabled in the debug build (e.g. an errata
workaround) but doesn't apply to the executing CPU's revision/part number.
However, in some cases the system integrator may want a single binary to
support multiple platforms with different IP versions, only some of which
contain a specific erratum.  In this case, the warning can be emitted very
frequently when CPUs are being powered on/off.

This patch modifies this warning print behaviour so that it is emitted only
when LOG_LEVEL >= LOG_LEVEL_VERBOSE. The `debug.h` header file now contains
guard macros so that it can be included in assembly code.

Change-Id: Ic6e7a07f128dcdb8498a5bfdae920a8feeea1345

Enable type-checking of arguments passed to printf() et al. ...

This patch modifies the declarations of the functions printf() et al.
and adds the right GCC attribute to request the compiler to check
the type of the arguments passed to these functions against the given
format string. This will ensure that the compiler outputs warning
messages like the following whenever it detects an inconsistency:

 file.c:42: warning: format ‘%d’ expects type ‘int’, but argument 3 has type ‘long int’

It also fixes the type mismatch inconsistencies that it revealed
across the code base.

NOTE: THIS PATCH MAY FORCE PLATFORM PORTS OR SP/SPDS THAT USE THE
PRINTF FAMILY OF FUNCTIONS TO FIX ANY TYPE MISMATCH INCONSISTENCIES.

Change-Id: If36bb54ec7d6dd2cb4791d89b02a24ac13fd2df6

Add concept of console output log levels ...

Create new LOG_LEVEL build option, which controls the amount of
console output compiled into the build. This should be one of the
following:

    0  (LOG_LEVEL_NONE)
    10 (LOG_LEVEL_NOTICE)
    20 (LOG_LEVEL_ERROR)
    30 (LOG_LEVEL_WARNING)
    40 (LOG_LEVEL_INFO)
    50 (LOG_LEVEL_VERBOSE)

All log output up to and including the log level is compiled into the
build. The default value is 40 in debug builds and 20 in release
builds.

Complement the existing INFO, WARN and ERROR console output macros
with NOTICE and VERBOSE macros, which are conditionally compiled in
depending on the value of LOG_LEVEL.

Fixes ARM-software/tf-issues#232

Change-Id: I951e2f333e7b90fc4b1060741d9a6db699d5aa72

Rework the crash reporting in BL3-1 to use less stack ...

This patch reworks the crash reporting mechanism to further
optimise the stack and code size. The reporting makes use
of assembly console functions to avoid calling C Runtime
to report the CPU state. The crash buffer requirement is
reduced to 64 bytes with this implementation. The crash
buffer is now part of per-cpu data which makes retrieving
the crash buffer trivial.

Also now panic() will use crash reporting if
invoked from BL3-1.

Fixes ARM-software/tf-issues#199

Change-Id: I79d27a4524583d723483165dc40801f45e627da5

Implement a leaner printf for Trusted Firmware ...

This patch implements a "tf_printf" which supports only the commonly
used format specifiers in Trusted Firmware, which uses a lot less
stack space than the stdlib printf function.

Fixes ARM-software/tf-issues#116

Change-Id: I7dfa1944f4c1e634b3e2d571f49afe02d109a351

Remove extern keyword from function declarations ...

Function declarations implicitly have external linkage so do not
need the extern keyword.

Change-Id: Ia0549786796d8bf5956487e8996450a0b3d79f32

Rework BL3-1 unhandled exception handling and reporting ...

This patch implements the register reporting when unhandled exceptions are
taken in BL3-1. Unhandled exceptions will result in a dump of registers
to the console, before halting execution by that CPU. The Crash Stack,
previously called the Exception Stack, is used for this activity.
This stack is used to preserve the CPU context and runtime stack
contents for debugging and analysis.

This also introduces the per_cpu_ptr_cache, referenced by tpidr_el3,
to provide easy access to some of BL3-1 per-cpu data structures.
Initially, this is used to provide a pointer to the Crash stack.

panic() now prints the the error file and line number in Debug mode
and prints the PC value in release mode.

The Exception Stack is renamed to Crash Stack with this patch.
The original intention of exception stack is no longer valid
since we intend to support several valid exceptions like IRQ
and FIQ in the trusted firmware context. This stack is now
utilized for dumping and reporting the system state when a
crash happens and hence the rename.

Fixes ARM-software/tf-issues#79 Improve reporting of unhandled exception

Change-Id: I260791dc05536b78547412d147193cdccae7811a

Reduce deep nesting of header files ...

Reduce the number of header files included from other header
files as much as possible without splitting the files. Use forward
declarations where possible. This allows removal of some unnecessary
"#ifndef __ASSEMBLY__" statements.

Also, review the .c and .S files for which header files really need
including and reorder the #include statements alphabetically.

Fixes ARM-software/tf-issues#31

Change-Id: Iec92fb976334c77453e010b60bcf56f3be72bd3e

Move include and source files to logical locations ...

Move almost all system include files to a logical sub-directory
under ./include. The only remaining system include directories
not under ./include are specific to the platform. Move the
corresponding source files to match the include directory
structure.

Also remove pm.h as it is no longer used.

Change-Id: Ie5ea6368ec5fad459f3e8a802ad129135527f0b3