Read-only xlat tables for BL31 memory ...

This patch introduces a build flag which allows the xlat tables
to be mapped in a read-only region within BL31 memory. It makes it
much harder for someone who has acquired the ability to write to
arbitrary secure memory addresses to gain control of the
translation tables.

The memory attributes of the descriptors describing the tables
themselves are changed to read-only secure data. This change
happens at the end of BL31 runtime setup. Until this point, the
tables have read-write permissions. This gives a window of
opportunity for changes to be made to the tables with the MMU on
(e.g. reclaiming init code). No changes can be made to the tables
with the MMU turned on from this point onwards. This change is also
enabled for sp_min and tspd.

To make all this possible, the base table was moved to .rodata. The
penalty we pay is that now .rodata must be aligned to the size of
the base table (512B alignment). Still, this is better than putting
the base table with the higher level tables in the xlat_table
section, as that would cost us a full 4KB page.

Changing the tables from read-write to read-only cannot be done with
the MMU on, as the break-before-make sequence would invalidate the
descriptor which resolves the level 3 page table where that very
descriptor is located. This would make the translation required for
writing the changes impossible, generating an MMU fault.

The caches are also flushed.

Signed-off-by: Petre-Ionut Tudor <petre-ionut.tudor@arm.com>
Change-Id: Ibe5de307e6dc94c67d6186139ac3973516430466

Add support for Branch Target Identification ...

This patch adds the functionality needed for platforms to provide
Branch Target Identification (BTI) extension, introduced to AArch64
in Armv8.5-A by adding BTI instruction used to mark valid targets
for indirect branches. The patch sets new GP bit [50] to the stage 1
Translation Table Block and Page entries to denote guarded EL3 code
pages which will cause processor to trap instructions in protected
pages trying to perform an indirect branch to any instruction other
than BTI.
BTI feature is selected by BRANCH_PROTECTION option which supersedes
the previous ENABLE_PAUTH used for Armv8.3-A Pointer Authentication
and is disabled by default. Enabling BTI requires compiler support
and was tested with GCC versions 9.0.0, 9.0.1 and 10.0.0.
The assembly macros and helpers are modified to accommodate the BTI
instruction.
This is an experimental feature.
Note. The previous ENABLE_PAUTH build option to enable PAuth in EL3
is now made as an internal flag and BRANCH_PROTECTION flag should be
used instead to enable Pointer Authentication.
Note. USE_LIBROM=1 option is currently not supported.

Change-Id: Ifaf4438609b16647dc79468b70cd1f47a623362e
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>

Remove deprecated interfaces ...

Change-Id: I14fcabbdfd53153d1d5f187f6f8b23a045794408
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>

PIE: Correct minor typographical errors ...

Change-Id: Ie7832b2ebffe15d53ffe3584e4d23a449d4f81ac
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>

Merge pull request #1810 from antonio-nino-diaz-arm/an/setjmp ...

Make setjmp/longjmp compliant with the C standard and move them to libc

libc: Move setjmp to libc folder ...

Now that setjmp() and longjmp() are compliant with the standard they can
be moved with the other libc files.

Change-Id: Iea3b91c34eb353ace5e171e72f331602d57774d5
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Make setjmp.h prototypes comply with the C standard ...

Instead of having a custom implementation of setjmp() and longjmp() it
is better to follow the C standard.

The comments in setjmp.h are no longer needed as there are no deviations
from the expected one, so they have been removed.

All SDEI code that relied on them has been fixed to use the new function
prototypes and structs.

Change-Id: I6cd2e21cb5a5bcf81ba12283f2e4c067bd5172ca
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

lib: aarch64: misc_helpers: include bl_common.h ...

This patch includes bl_common.h to get access to the linker
defined symbols.

Change-Id: I9aa4a6e730273d75a53438854f69971e485bc904
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

Remove unused function symbols ...

This patch removes the unused functions that are marked as .global
in code but not defined anywhere in the code.

Change-Id: Ia5057a77c0b0b4a61043eab868734cd3437304cc
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

lib: aarch64: fix non-code symbol errors flagged by armlink ...

This patch modifies the code to turn __1printf and __2printf into proper
functions to fix the following errors flagged by armlink.

Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.
Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.
Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.
Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.
Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.
Error: L6318W: backtrace.o(.text.backtrace) contains branch to a non-code symbol __2printf.

Change-Id: I89126bc2b9db44ce8b8fc9fb1e3fc4c8c60c47a4
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

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>

Deprecate some unused AArch64 assembly functions ...

Change-Id: I8a0be21783a0c12325e6ab22e9e53ab5466ed9e0
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

PIE: Position Independant Executable support for BL31 ...

This patch introduces Position Independant Executable(PIE) support
in TF-A. As a initial prototype, only BL31 can support PIE. A trivial
dynamic linker is implemented which supports fixing up Global Offset
Table(GOT) and Dynamic relocations(.rela.dyn). The fixup_gdt_reloc()
helper function implements this linker and this needs to be called
early in the boot sequence prior to invoking C functions. The GOT is
placed in the RO section of BL31 binary for improved security and the
BL31 linker script is modified to export the appropriate symbols
required for the dynamic linker.

The C compiler always generates PC relative addresses to linker symbols
and hence referencing symbols exporting constants are a problem when
relocating the binary. Hence the reference to the
`__PERCPU_TIMESTAMP_SIZE__` symbol in PMF is removed and is now calculated
at runtime based on start and end addresses.

Change-Id: I1228583ff92cf432963b7cef052e95d995cca93d
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

Remove all other deprecated interfaces and files ...

Change-Id: Icd1cdd42afdc78895a9be6c46b414b0a155cfa63
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

xlat: Remove deprecated interfaces ...

Change-Id: I83de2ae3e0795e6fec3c1e5b37c441b64b0c9cb6
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

libc: armclang: Implement compiler printf symbols ...

armclang replaces calls to printf by calls to one of the symbols
__0printf, __1printf or __2printf. This patch adds new functions with
these names that internally call printf so that the Trusted Firmware can
be compiled with this compiler.

Change-Id: I06a0e3e5001232fe5b2577615666ddd66e81eef0
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

BL31: Introduce jump primitives ...

This patch introduces setjmp() and ongjmp() primitives to enable
standard setjmp/longjmp style execution. Both APIs parameters take a
pointer to struct jmpbuf type, which hosts CPU registers saved/restored
during jump.

As per the standard usage:

  - setjmp() return 0 when a jump is setup; and a non-zero value when
    returning from jump.

  - The caller of setjmp() must not return, or otherwise update stack
    pointer since.

Change-Id: I4af1d32e490cfa547979631b762b4cba188d0551
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

misc_helpers: fix zero_normalmem() for BL2_AT_EL3 ...

The assertion in zero_normalmem() fails for BL2_AT_EL3.  This mode is
executed in EL3, so it should check sctlr_el3 instead of sctlr_el1.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Introduce functions to disable the MMU in EL1 ...

The implementation is the same as those used to disable it in EL3.

Change-Id: Ibfe7e69034a691fbf57477c5a76a8cdca28f6b26
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Exit early if size zero for cache helpers ...

This patch enables cache helper functions `flush_dcache_range`,
`clean_dcache_range` and `invalidate_dcache_range` to exit early
if the size argument specified is zero

Change-Id: I0b63e8f4bd3d47ec08bf2a0b0b9a7ff8a269a9b0
Signed-off-by: Soby Mathew <soby.mathew@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>

Remove build option `ASM_ASSERTION` ...

The build option `ENABLE_ASSERTIONS` should be used instead. That way
both C and ASM assertions can be enabled or disabled together.

All occurrences of `ASM_ASSERTION` in common code and ARM platforms have
been replaced by `ENABLE_ASSERTIONS`.

ASM_ASSERTION has been removed from the user guide.

Change-Id: I51f1991f11b9b7ff83e787c9a3270c274748ec6f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Replace ASM signed tests with unsigned ...

ge, lt, gt and le condition codes in assembly provide a signed test
whereas hs, lo, hi and ls provide the unsigned counterpart. Signed tests
should only be used when strictly necessary, as using them on logically
unsigned values can lead to inverting the test for high enough values.
All offsets, addresses and usually counters are actually unsigned
values, and should be tested as such.

Replace the occurrences of signed condition codes where it was
unnecessary by an unsigned test as the unsigned tests allow the full
range of unsigned values to be used without inverting the result with
some large operands.

Change-Id: I58b7e98d03e3a4476dfb45230311f296d224980a
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

Introduce unified API to zero memory ...

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>

Fix integer comparison in memcpy16 ...

Unsigned conditions should be used instead of signed ones when comparing
addresses or sizes in assembly.

Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
Change-Id: Id3bd9ccaf58c37037761af35ac600907c4bb0580

Refactor the xlat_tables library code ...

The AArch32 long descriptor format and the AArch64 descriptor format
correspond to each other which allows possible sharing of xlat_tables
library code between AArch64 and AArch32. This patch refactors the
xlat_tables library code to seperate the common functionality from
architecture specific code. Prior to this patch, all of the xlat_tables
library code were in `lib/aarch64/xlat_tables.c` file. The refactored code
is now in `lib/xlat_tables/` directory. The AArch64 specific programming
for xlat_tables is in `lib/xlat_tables/aarch64/xlat_tables.c` and the rest
of the code common to AArch64 and AArch32 is in
`lib/xlat_tables/xlat_tables_common.c`. Also the data types used in
xlat_tables library APIs are reworked to make it compatible between AArch64
and AArch32.

The `lib/aarch64/xlat_tables.c` file now includes the new xlat_tables
library files to retain compatibility for existing platform ports.
The macros related to xlat_tables library are also moved from
`include/lib/aarch64/arch.h` to the header `include/lib/xlat_tables.h`.

NOTE: THE `lib/aarch64/xlat_tables.c` FILE IS DEPRECATED AND PLATFORM PORTS
ARE EXPECTED TO INCLUDE THE NEW XLAT_TABLES LIBRARY FILES IN THEIR MAKEFILES.

Change-Id: I3d17217d24aaf3a05a4685d642a31d4d56255a0f

Remove xlat_helpers.c ...

lib/aarch64/xlat_helpers.c defines helper functions to build
translation descriptors, but no common code or upstream platform
port uses them. As the rest of the xlat_tables code evolves, there
may be conflicts with these helpers, therefore this code should be
removed.

Change-Id: I9f5be99720f929264818af33db8dada785368711

Merge pull request #542 from sandrine-bailleux-arm/km/pt-zero ...

Initialize all translation table entries

Initialize all translation table entries ...

The current translation table code maps in a series of regions, zeroing
the unmapped table entries before and in between the mapped regions. It
doesn't, however, zero the unmapped entries after the last mapped
region, leaving those entries at whatever value that memory has
initially.

This is bad because those values can look like valid translation table
entries, pointing to valid physical addresses. The CPU is allowed to do
speculative reads from any such addresses. If the addresses point to
device memory, the results can be unpredictable.

This patch zeroes the translation table entries following the last
mapped region, ensuring all table entries are either valid or zero
(invalid).

In addition, it limits the value of ADDR_SPACE_SIZE to those allowed by
the architecture and supported by the current code (see D4.2.5 in the
Architecture Reference Manual). This simplifies this patch a lot and
ensures existing code doesn't do unexpected things.

Change-Id: Ic28b6c3f89d73ef58fa80319a9466bb2c7131c21

Extend memory attributes to map non-cacheable memory ...

At the moment, the memory translation library allows to create memory
mappings of 2 types:

 - Device nGnRE memory (named MT_DEVICE in the library);

 - Normal, Inner Write-back non-transient, Outer Write-back
   non-transient memory (named MT_MEMORY in the library).

As a consequence, the library code treats the memory type field as a
boolean: everything that is not device memory is normal memory and
vice-versa.

In reality, the ARMv8 architecture allows up to 8 types of memory to
be used at a single time for a given exception level. This patch
reworks the memory attributes such that the memory type is now defined
as an integer ranging from 0 to 7 instead of a boolean. This makes it
possible to extend the list of memory types supported by the memory
translation library.

The priority system dictating memory attributes for overlapping
memory regions has been extended to cope with these changes but the
algorithm at its core has been preserved. When a memory region is
re-mapped with different memory attributes, the memory translation
library examines the former attributes and updates them only if
the new attributes create a more restrictive mapping. This behaviour
is unchanged, only the manipulation of the value has been modified
to cope with the new format.

This patch also introduces a new type of memory mapping in the memory
translation library: MT_NON_CACHEABLE, meaning Normal, Inner
Non-cacheable, Outer Non-cacheable memory. This can be useful to map
a non-cacheable memory region, such as a DMA buffer for example.

The rules around the Execute-Never (XN) bit in a translation table
for an MT_NON_CACHEABLE memory mapping have been aligned on the rules
used for MT_MEMORY mappings:
 - If the memory is read-only then it is also executable (XN = 0);
 - If the memory is read-write then it is not executable (XN = 1).

The shareability field for MT_NON_CACHEABLE mappings is always set as
'Outer-Shareable'. Note that this is not strictly needed since
shareability is only relevant if the memory is a Normal Cacheable
memory type, but this is to align with the existing device memory
mappings setup. All Device and Normal Non-cacheable memory regions
are always treated as Outer Shareable, regardless of the translation
table shareability attributes.

This patch also removes the 'ATTR_SO' and 'ATTR_SO_INDEX' #defines.
They were introduced to map memory as Device nGnRnE (formerly called
"Strongly-Ordered" memory in the ARMv7 architecture) but were not
used anywhere in the code base. Removing them avoids any confusion
about the memory types supported by the library.

Upstream platforms do not currently use the MT_NON_CACHEABLE memory
type.

NOTE: THIS CHANGE IS SOURCE COMPATIBLE BUT PLATFORMS THAT RELY ON THE
BINARY VALUES OF `mmap_attr_t` or the `attr` argument of
`mmap_add_region()` MAY BE BROKEN.

Change-Id: I717d6ed79b4c845a04e34132432f98b93d661d79