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Double fault is when the PE receives another error whilst one is being
handled. To detect double fault condition, a per-CPU flag is introduced
to track the status of error handling. The flag is checked/modified
while temporarily masking external aborts on the PE.

This patch routes double faults to a separate platform-defined handler.

Change-Id: I70e9b7ba4c817273c55a0af978d9755ff32cc702
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Uncontainable errors are the most severe form of errors, which typically
mean that the system state can't be trusted any more. This further means
that normal error recovery process can't be followed, and an orderly
shutdown of the system is often desirable.

This patch allows for the platform to define a handler for Uncontainable
errors received. Due to the nature of Uncontainable error, the handler
is expected to initiate an orderly shutdown of the system, and therefore
is not expected to return. A default implementation is added which falls
back to platform unhandled exception.

Also fix ras_arch.h header guards.

Change-Id: I072e336a391a0b382e77e627eb9e40729d488b55
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

RAS handling flows might involve using setjmp/longjump calls introduced
in earlier patches; therefore, it'd be good to make sure the stack has
been unwound completely after the handling.

This patch inserts ASM assertions on the RAS handling path to validate
stack.

Change-Id: I59d40d3122010c977cdeab3cce3160f3909e7e69
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

A new file ea_delegate.S is introduced, and all EA-related functions are
moved into it. This makes runtime_exceptions.S less crowded and reads
better.

No functional changes.

Change-Id: I64b653b3931984cffd420563f8e8d1ba263f329f
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Check_vector_size checks if the size of the vector fits
in the size reserved for it. This check creates problems in
the Clang assembler. A new macro, end_vector_entry, is added
and check_vector_size is deprecated.

This new macro fills the current exception vector until the next
exception vector. If the size of the current vector is bigger
than 32 instructions then it gives an error.

Change-Id: Ie8545cf1003a1e31656a1018dd6b4c28a4eaf671
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Having an active stack while enabling MMU has shown coherency problems.
This patch builds on top of translation library changes that introduces
MMU-enabling without using stacks.

Previously, with HW_ASSISTED_COHERENCY, data caches were disabled while
enabling MMU only because of active stack. Now that we can enable MMU
without using stack, we can enable both MMU and data caches at the same
time.

NOTE: Since this feature depends on using translation table library v2,
disallow using translation table library v1 with HW_ASSISTED_COHERENCY.

Fixes ARM-software/tf-issues#566

Change-Id: Ie55aba0c23ee9c5109eb3454cb8fa45d74f8bbb2
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

RAS extensions are mandatory for ARMv8.2 CPUs, but are also optional
extensions to base ARMv8.0 architecture.

This patch adds build system support to enable RAS features in ARM
Trusted Firmware. A boolean build option RAS_EXTENSION is introduced for
this.

With RAS_EXTENSION, an Exception Synchronization Barrier (ESB) is
inserted at all EL3 vector entry and exit. ESBs will synchronize pending
external aborts before entering EL3, and therefore will contain and
attribute errors to lower EL execution. Any errors thus synchronized are
detected via. DISR_EL1 register.

When RAS_EXTENSION is set to 1, HANDLE_EL3_EA_FIRST must also be set to 1.

Change-Id: I38a19d84014d4d8af688bd81d61ba582c039383a
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

At present, any External Abort routed to EL3 is reported as an unhandled
exception and cause a panic. This patch enables ARM Trusted Firmware to
handle External Aborts routed to EL3.

With this patch, when an External Abort is received at EL3, its handling
is delegated to plat_ea_handler() function. Platforms can provide their
own implementation of this function. This patch adds a weak definition
of the said function that prints out a message and just panics.

In order to support handling External Aborts at EL3, the build option
HANDLE_EA_EL3_FIRST must be set to 1.

Before this patch, HANDLE_EA_EL3_FIRST wasn't passed down to
compilation; this patch fixes that too.

Change-Id: I4d07b7e65eb191ff72d63b909ae9512478cd01a1
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

At present, the function that restores general purpose registers also
does ERET. Refactor the restore code to restore general purpose
registers without ERET to complement the save function.

The macro save_x18_to_x29_sp_el0 was used only once, and is therefore
removed, and its contents expanded inline for readability.

No functional changes, but with this patch:

  - The SMC return path will incur an branch-return and an additional
    register load.

  - The unknown SMC path restores registers x0 to x3.

Change-Id: I7a1a63e17f34f9cde810685d70a0ad13ca3b7c50
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Due to differences in the bitfields of the SMC IDs, it is not possible
to support SMCCC 1.X and 2.0 at the same time.

The behaviour of `SMCCC_MAJOR_VERSION` has changed. Now, it is a build
option that specifies the major version of the SMCCC that the Trusted
Firmware supports. The only two allowed values are 1 and 2, and it
defaults to 1. The value of `SMCCC_MINOR_VERSION` is derived from it.

Note: Support for SMCCC v2.0 is an experimental feature to enable
prototyping of secure partition specifications. Support for this
convention is disabled by default and could be removed without notice.

Change-Id: I88abf9ccf08e9c66a13ce55c890edea54d9f16a7
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@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>

This patch introduces a new BL handover interface. It essentially allows
passing 4 arguments between the different BL stages. Effort has been made
so as to be compatible with the previous handover interface. The previous
blx_early_platform_setup() platform API is now deprecated and the new
blx_early_platform_setup2() variant is introduced. The weak compatiblity
implementation for the new API is done in the `plat_bl_common.c` file.
Some of the new arguments in the new API will be reserved for generic
code use when dynamic configuration support is implemented. Otherwise
the other registers are available for platform use.

Change-Id: Ifddfe2ea8e32497fe1beb565cac155ad9d50d404
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

According to the SMC Calling Convention (ARM DEN0028B):

    The Unknown SMC Function Identifier is a sign-extended value of
    (-1) that is returned in R0, W0 or X0 register.

The value wasn't sign-extended because it was defined as a 32-bit
unsigned value (0xFFFFFFFF).

SMC_PREEMPT has been redefined as -2 for the same reason.

NOTE: This might be a compatibility break for some AArch64 platforms
that don't follow the previous version of the SMCCC (ARM DEN0028A)
correctly. That document specifies that only the bottom 32 bits of the
returned value must be checked. If a platform relies on the top 32 bits
of the result being 0 (so that SMC_UNK is 0x00000000FFFFFFFF), it will
have to fix its code to comply with the SMCCC.

Change-Id: I7f7b109f6b30c114fe570aa0ead3c335383cb54d
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

In preparation for SMCCC v1.1 support, save x4 to x29 unconditionally.
Previously we expected callers coming from AArch64 mode to preserve
x8-x17.  This is no longer the case with SMCCC v1.1 as AArch64 callers
only need to save x0-x3.

Change-Id: Ie62d620776533969ff4a02c635422f1b9208be9c
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Invalidate the Branch Target Buffer (BTB) on entry to EL3 by disabling
and enabling the MMU.  To achieve this without performing any branch
instruction, a per-cpu vbar is installed which executes the workaround
and then branches off to the corresponding vector entry in the main
vector table.  A side effect of this change is that the main vbar is
configured before any reset handling.  This is to allow the per-cpu
reset function to override the vbar setting.

This workaround is enabled by default on the affected CPUs.

Change-Id: I97788d38463a5840a410e3cea85ed297a1678265
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

In assembly code it can be useful to have a constant for the width of a
register in the current architecture, so this patch adds one to
<utils_def.h> and replaces the existing custom one in crash_reporting.S
with that. It also fixes up the BIT() macro in the same file so that it
can be safely used in assembly code.

Change-Id: I10513a311f3379e767396e6ddfbae8d2d8201464
Signed-off-by: Julius Werner <jwerner@chromium.org>

The FPEXC32_EL2 register controls SIMD and FP functionality when the
lower ELs are executing in AArch32 mode. It is architecturally mapped
to AArch32 system register FPEXC.

This patch removes FPEXC32_EL2 register from the System Register context
and adds it to the floating-point context. EL3 only saves / restores the
floating-point context if the build option CTX_INCLUDE_FPREGS is set to 1.

The rationale for this change is that if the Secure world is using FP
functionality and EL3 is not managing the FP context, then the Secure
world will save / restore the appropriate FP registers.

NOTE - this is a break in behaviour in the unlikely case that
CTX_INCLUDE_FPREGS is set to 0 and the platform contains an AArch32
Secure Payload that modifies FPEXC, but does not save and restore
this register

Change-Id: Iab80abcbfe302752d52b323b4abcc334b585c184
Signed-off-by: David Cunado <david.cunado@arm.com>

Some error paths that lead to a crash dump will overwrite the value in
the x30 register by calling functions with the no_ret macro, which
resolves to a BL instruction. This is not very useful and not what the
reader would expect, since a crash dump should usually show all
registers in the state they were in when the exception happened. This
patch replaces the offending function calls with a B instruction to
preserve the value in x30.

Change-Id: I2a3636f2943f79bab0cd911f89d070012e697c2a
Signed-off-by: Julius Werner <jwerner@chromium.org>

This patch updates the el3_arch_init_common macro so that it fully
initialises essential control registers rather then relying on hardware
to set the reset values.

The context management functions are also updated to fully initialise
the appropriate control registers when initialising the non-secure and
secure context structures and when preparing to leave EL3 for a lower
EL.

This gives better alignement with the ARM ARM which states that software
must initialise RES0 and RES1 fields with 0 / 1.

This patch also corrects the following typos:

"NASCR definitions" -> "NSACR definitions"

Change-Id: Ia8940b8351dc27bc09e2138b011e249655041cfc
Signed-off-by: David Cunado <david.cunado@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>

This patch introduces a build option to enable D-cache early on the CPU
after warm boot. This is applicable for platforms which do not require
interconnect programming to enable cache coherency (eg: single cluster
platforms). If this option is enabled, then warm boot path enables
D-caches immediately after enabling MMU.

Fixes ARM-Software/tf-issues#456

Change-Id: I44c8787d116d7217837ced3bcf0b1d3441c8d80e
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

This API makes sure that all the characters sent to the crash console
are output before returning from it.

Porting guide updated.

Change-Id: I1785f970a40f6aacfbe592b6a911b1f249bb2735
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

The files affected by this patch don't really depend on `xlat_tables.h`.
By changing the included file it becomes easier to switch between the
two versions of the translation tables library.

Change-Id: Idae9171c490e0865cb55883b19eaf942457c4ccc
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

At present, warm-booted CPUs keep their caches disabled when enabling
MMU, and remains so until they enter coherency later.

On systems with hardware-assisted coherency, for which
HW_ASSISTED_COHERENCY build flag would be enabled, warm-booted CPUs can
have both caches and MMU enabled at once.

Change-Id: Icb0adb026e01aecf34beadf49c88faa9dd368327
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@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>

* Move comments on unhandled exceptions at the right place.
* Reformat the existing comments to highlight the start of
  each block of 4 entries in the exception table to ease
  navigation (lines of dash reserved for head comments).
* Reflow comments to 80 columns.

Change-Id: I5ab88a93d0628af8e151852cb5b597eb34437677
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

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>

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

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

This patch introduces some assembler macros to simplify the
declaration of the exception vectors. It abstracts the section
the exception code is put into as well as the alignments
constraints mandated by the ARMv8 architecture. For all TF images,
the exception code has been updated to make use of these macros.

This patch also updates some invalid comments in the exception
vector code.

Change-Id: I35737b8f1c8c24b6da89b0a954c8152a4096fa95

Added plat_get_syscnt_freq2, which is a 32 bit variant of the 64 bit
plat_get_syscnt_freq. The old one has been flagged as deprecated.
Common code has been updated to use this new version. Porting guide
has been updated.

Change-Id: I9e913544926c418970972bfe7d81ee88b4da837e

It is up to the platform to implement the new plat_crash_print_regs macro to
report all relevant platform registers helpful for troubleshooting.

plat_crash_print_regs merges or calls previously defined plat_print_gic_regs
and plat_print_interconnect_regs macros for each existing platforms.

NOTE: THIS COMMIT REQUIRES ALL PLATFORMS THAT ENABLE THE `CRASH_REPORTING`
BUILD FLAG TO MIGRATE TO USE THE NEW `plat_crash_print_regs()` MACRO. BY
DEFAULT, `CRASH_REPORTING` IS ENABLED IN DEBUG BUILDS FOR ALL PLATFORMS.

Fixes: arm-software/tf-issues#373
Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

Bring ISR bits definition as a mnemonic for troublershooters as well.
Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

Asynchronous abort exceptions generated by the platform during cold boot are
not taken in EL3 unless SCR_EL3.EA is set.

Therefore EA bit is set along with RES1 bits in early BL1 and BL31 architecture
initialisation. Further write accesses to SCR_EL3 preserve these bits during
cold boot.

A build flag controls SCR_EL3.EA value to keep asynchronous abort exceptions
being trapped by EL3 after cold boot or not.

For further reference SError Interrupts are also known as asynchronous external
aborts.

On Cortex-A53 revisions below r0p2, asynchronous abort exceptions are taken in
EL3 whatever the SCR_EL3.EA value is.

Fixes arm-software/tf-issues#368
Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

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

Change-Id: I6f49bd779f2a4d577c6443dd160290656cdbc59b

This patch removes the dash character from the image name, to
follow the image terminology in the Trusted Firmware Wiki page:

    https://github.com/ARM-software/arm-trusted-firmware/wiki

Changes apply to output messages, comments and documentation.

non-ARM platform files have been left unmodified.

Change-Id: Ic2a99be4ed929d52afbeb27ac765ceffce46ed76

The upcoming Firmware Update feature needs transitioning across
Secure/Normal worlds to complete the FWU process and hence requires
context management code to perform this task.

Currently context management code is part of BL31 stage only.
This patch moves the code from (include)/bl31 to (include)/common.
Some function declarations/definitions and macros have also moved
to different files to help code sharing.

Change-Id: I3858b08aecdb76d390765ab2b099f457873f7b0c

The `fpregs_context_restore()` function used to restore the floating point
regsiter context had a typo error wherein it was doing `str` instead of
`ldr` for a register. This issue remained undetected becuase none of the ARM
Standard development platforms save and restore the floating point register
context when a context switch is done. This patch corrects the issue.

Change-Id: Id178e0ba254a5e0a4a844f54b39d71dc34e0f6ea

This patch introduces a new build option named COLD_BOOT_SINGLE_CPU,
which allows platforms that only release a single CPU out of reset to
slightly optimise their cold boot code, both in terms of code size
and performance.

COLD_BOOT_SINGLE_CPU defaults to 0, which assumes that the platform
may release several CPUs out of reset. In this case, the cold reset
code needs to coordinate all CPUs via the usual primary/secondary
CPU distinction.

If a platform guarantees that only a single CPU will ever be released
out of reset, there is no need to arbitrate execution ; the notion of
primary and secondary CPUs itself no longer exists. Such platforms
may set COLD_BOOT_SINGLE_CPU to 1 in order to compile out the
primary/secondary CPU identification in the cold reset code.

All ARM standard platforms can release several CPUs out of reset
so they use COLD_BOOT_SINGLE_CPU=0. However, on CSS platforms like
Juno, bringing up more than one CPU at reset should only be attempted
when booting an EL3 payload, as it is not fully supported in the
normal boot flow.

For platforms using COLD_BOOT_SINGLE_CPU=1, the following 2 platform
APIs become optional:
  - plat_secondary_cold_boot_setup();
  - plat_is_my_cpu_primary().
The Porting Guide has been updated to reflect that.

User Guide updated as well.

Change-Id: Ic5b474e61b7aec1377d1e0b6925d17dfc376c46b