The SCTLR.DSSBS bit is zero by default thus disabling speculative loads.
However, we also explicitly set it to zero for BL2 and TSP images when
each image initialises its context. This is done to ensure that the
image environment is initialised in a safe state, regardless of the
reset value of the bit.
Change-Id: If25a8396641edb640f7f298b8d3309d5cba3cd79
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>
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: e0ea0928d5 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a2 ("drivers: add tzc380 support").
This problem was introduced in commit 4ecca33988 ("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>
We had exit but we didn't have atexit, and we were calling panic and
tf_printf from exit, which generated a dependency from exit to them.
Having atexit allows to set a different function pointer in every image.
Change-Id: I95b9556d680d96249ed3b14da159b6f417da7661
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
These sections are required by clang when the code is compiled for
aarch32. These sections are related to the unwind of the stack in
exceptions, but in the way that clang defines and uses them, the
garbage collector cannot get rid of them.
Change-Id: I085efc0cf77eae961d522472f72c4b5bad2237ab
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
Clang linker doesn't support NEXT. As we are not using the MEMORY command
to define discontinuous memory for the output file in any of the linker
scripts, ALIGN and NEXT are equivalent.
Change-Id: I867ffb9c9a76d4e81c9ca7998280b2edf10efea0
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
Rule 8.4: A compatible declaration shall be visible when
an object or function with external linkage is defined.
Change-Id: I26e042cb251a6f9590afa1340fdac73e42f23979
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
When the MMU is enabled and the translation tables are mapped, data
read/writes to the translation tables are made using the attributes
specified in the translation tables themselves. However, the MMU
performs table walks with the attributes specified in TCR_ELx. They are
completely independent, so special care has to be taken to make sure
that they are the same.
This has to be done manually because it is not practical to have a test
in the code. Such a test would need to know the virtual memory region
that contains the translation tables and check that for all of the
tables the attributes match the ones in TCR_ELx. As the tables may not
even be mapped at all, this isn't a test that can be made generic.
The flags used by enable_mmu_xxx() have been moved to the same header
where the functions are.
Also, some comments in the linker scripts related to the translation
tables have been fixed.
Change-Id: I1754768bffdae75f53561b1c4a5baf043b45a304
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
When defining different sections in linker scripts it is needed to align
them to multiples of the page size. In most linker scripts this is done
by aligning to the hardcoded value 4096 instead of PAGE_SIZE.
This may be confusing when taking a look at all the codebase, as 4096
is used in some parts that aren't meant to be a multiple of the page
size.
Change-Id: I36c6f461c7782437a58d13d37ec8b822a1663ec1
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Replace the use of r12 by r10 to save the value of a parameter of
bl2u_entrypoint to pass it to bl2u_early_platform_setup at the end of
the function. r10 is a callee saved register so it will not become
corrupted by C code, whereas r12 is the The Intra-Procedure-call scratch
register potentially used by veneers. See the ARM AAPCS document (ARM
IHI 0042F).
Change-Id: I4f37e54a6b550719edb40bb24cd8f498827e2749
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
This fix modifies the order of system includes to meet the ARM TF coding
standard. There are some exceptions in order to retain header groupings,
minimise changes to imported headers, and where there are headers within
the #if and #ifndef statements.
Change-Id: I65085a142ba6a83792b26efb47df1329153f1624
Signed-off-by: Isla Mitchell <isla.mitchell@arm.com>
Add support for firmware upgrade on AArch32.
This patch has been tested on the FVP models.
NOTE: Firmware upgrade on Juno AArch32 is not currently supported.
Change-Id: I1ca8078214eaf86b46463edd14740120af930aec
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Co-Authored-By: Yatharth Kochar <yatharth.kochar@arm.com>
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>
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>
Call console_flush() before execution either terminates or leaves an
exception level.
Fixes: ARM-software/tf-issues#123
Change-Id: I64eeb92effb039f76937ce89f877b68e355588e3
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
These source file definitions should be defined in generic
Makefiles so that all platforms can benefit. Ensure that the
symbols are properly marked as weak so they can be overridden
by platforms.
NOTE: This change is a potential compatibility break for
non-upstream platforms.
Change-Id: I7b892efa9f2d6d216931360dc6c436e1d10cffed
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
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.
FixesARM-software/tf-issues#408
Change-Id: Iafd9663fc1070413c3e1904e54091cf60effaa82
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
There are many instances in ARM Trusted Firmware where control is
transferred to functions from which return isn't expected. Such jumps
are made using 'bl' instruction to provide the callee with the location
from which it was jumped to. Additionally, debuggers infer the caller by
examining where 'lr' register points to. If a 'bl' of the nature
described above falls at the end of an assembly function, 'lr' will be
left pointing to a location outside of the function range. This misleads
the debugger back trace.
This patch defines a 'no_ret' macro to be used when jumping to functions
from which return isn't expected. The macro ensures to use 'bl'
instruction for the jump, and also, for debug builds, places a 'nop'
instruction immediately thereafter (unless instructed otherwise) so as
to leave 'lr' pointing within the function range.
Change-Id: Ib34c69fc09197cfd57bc06e147cc8252910e01b0
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
At the moment, all BL images share a similar memory layout: they start
with their code section, followed by their read-only data section.
The two sections are contiguous in memory. Therefore, the end of the
code section and the beginning of the read-only data one might share
a memory page. This forces both to be mapped with the same memory
attributes. As the code needs to be executable, this means that the
read-only data stored on the same memory page as the code are
executable as well. This could potentially be exploited as part of
a security attack.
This patch introduces a new build flag called
SEPARATE_CODE_AND_RODATA, which isolates the code and read-only data
on separate memory pages. This in turn allows independent control of
the access permissions for the code and read-only data.
This has an impact on memory footprint, as padding bytes need to be
introduced between the code and read-only data to ensure the
segragation of the two. To limit the memory cost, the memory layout
of the read-only section has been changed in this case.
- When SEPARATE_CODE_AND_RODATA=0, the layout is unchanged, i.e.
the read-only section still looks like this (padding omitted):
| ... |
+-------------------+
| Exception vectors |
+-------------------+
| Read-only data |
+-------------------+
| Code |
+-------------------+ BLx_BASE
In this case, the linker script provides the limits of the whole
read-only section.
- When SEPARATE_CODE_AND_RODATA=1, the exception vectors and
read-only data are swapped, such that the code and exception
vectors are contiguous, followed by the read-only data. This
gives the following new layout (padding omitted):
| ... |
+-------------------+
| Read-only data |
+-------------------+
| Exception vectors |
+-------------------+
| Code |
+-------------------+ BLx_BASE
In this case, the linker script now exports 2 sets of addresses
instead: the limits of the code and the limits of the read-only
data. Refer to the Firmware Design guide for more details. This
provides platform code with a finer-grained view of the image
layout and allows it to map these 2 regions with the appropriate
access permissions.
Note that SEPARATE_CODE_AND_RODATA applies to all BL images.
Change-Id: I936cf80164f6b66b6ad52b8edacadc532c935a49
Added a new platform porting function plat_panic_handler, to allow
platforms to handle unexpected error situations. It must be
implemented in assembly as it may be called before the C environment
is initialized. A default implementation is provided, which simply
spins.
Corrected all dead loops in generic code to call this function
instead. This includes the dead loop that occurs at the end of the
call to panic().
All unnecesary wfis from bl32/tsp/aarch64/tsp_exceptions.S have
been removed.
Change-Id: I67cb85f6112fa8e77bd62f5718efcef4173d8134
The Firmware Update (FWU) feature needs support for an optional
secure world image, BL2U, to allow additional secure world
initialization required by FWU, for example DDR initialization.
This patch adds generic framework support to create BL2U.
NOTE: A platform makefile must supply additional `BL2U_SOURCES`
to build the bl2u target. A subsequent patch adds bl2u
support for ARM platforms.
Change-Id: If2ce036199bb40b39b7f91a9332106bcd4e25413
John Tsichritzis
Antonio Nino Diaz
Roberto Vargas
Douglas Raillard
Isla Mitchell
Yatharth Kochar
dp-arm
Jeenu Viswambharan
Sandrine Bailleux