This patch removes RAS_FFH_SUPPORT macro which is the combination of
ENABLE_FEAT_RAS and HANDLE_EA_EL3_FIRST_NS. Instead introduce an
internal macro FFH_SUPPORT which gets enabled when platforms wants
to enable lower EL EA handling at EL3. The internal macro FFH_SUPPORT
will be automatically enabled if HANDLE_EA_EL3_FIRST_NS is enabled.
FFH_SUPPORT along with ENABLE_FEAT_RAS will be used in source files
to provide equivalent check which was provided by RAS_FFH_SUPPORT
earlier. In generic code we needed a macro which could abstract both
HANDLE_EA_EL3_FIRST_NS and RAS_FFH_SUPPORT macros that had limitations.
Former was tied up with NS world only while the latter was tied to RAS
feature.
This is to allow Secure/Realm world to have their own FFH macros
in future.
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: Ie5692ccbf462f5dcc3f005a5beea5aa35124ac73
Vector entries in EL3 from lower ELs, first check for any pending
async EAs from lower EL before handling the original exception.
This happens when there is an error (EA) in the system which is not
yet signaled to PE while executing at lower EL. During entry into EL3
the errors (EA) are synchronized causing async EA to pend at EL3.
On detecting the pending EA (via ISR_EL1.A) EL3 either reflects it back
to lower EL (KFH) or handles it in EL3 (FFH) based on EA routing model.
In case of Firmware First handling mode (FFH), EL3 handles the pended
EA first before returing back to handle the original exception.
While in case of Kernel First handling mode (KFH), EL3 will return back
to lower EL without handling the original exception. On returing to
lower EL, EA will be pended. In KFH mode there is a risk of back and
forth between EL3 and lower EL if the EA is masked at lower EL or
priority of EA is lower than that of original exception. This is a
limitation in current architecture but can be solved in future if EL3
gets a capability to inject virtual SError.
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I3a2a31de7cf454d9d690b1ef769432a5b24f6c11
The current usage of RAS_EXTENSION in TF-A codebase is to cater for two
things in TF-A :
1. Pull in necessary framework and platform hooks for Firmware first
handling(FFH) of RAS errors.
2. Manage the FEAT_RAS extension when switching the worlds.
FFH means that all the EAs from NS are trapped in EL3 first and signaled
to NS world later after the first handling is done in firmware. There is
an alternate way of handling RAS errors viz Kernel First handling(KFH).
Tying FEAT_RAS to RAS_EXTENSION build flag was not correct as the
feature is needed for proper handling KFH in as well.
This patch breaks down the RAS_EXTENSION flag into a flag to denote the
CPU architecture `ENABLE_FEAT_RAS` which is used in context management
during world switch and another flag `RAS_FFH_SUPPORT` to pull in
required framework and platform hooks for FFH.
Proper support for KFH will be added in future patches.
BREAKING CHANGE: The previous RAS_EXTENSION is now deprecated. The
equivalent functionality can be achieved by the following
2 options:
- ENABLE_FEAT_RAS
- RAS_FFH_SUPPORT
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I1abb9ab6622b8f1b15712b12f17612804d48a6ec
Reading back a RES0 bit does not necessarily mean it will be read as 0.
The Arm ARM explicitly warns against doing this. The PMU initialisation
code tries to set such bits to 1 (in MDCR_EL3) regardless of whether
they are in use or are RES0, checking their value could be wrong and
PMCR_EL0 might not end up being saved.
Save PMCR_EL0 unconditionally to prevent this. Remove the security state
change as the outgoing state is not relevant to what the root world
context should look like.
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: Id43667d37b0e2da3ded0beaf23fa0d4f9013f470
Current panic call invokes do_panic which calls el3_panic, but now panic
handles only panic from EL3 anid clear separation to use lower_el_panic()
which handles panic from lower ELs.
So now we can remove do_panic and just call el3_panic for all panics.
Change-Id: I739c69271b9fb15c1176050877a9b0c0394dc739
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
handle_lower_el_async_ea and enter_lower_el_async_ea are same except for
saving x30 register, with previous patch x30 is now freed before calling
these function we don't need both of them.
This patch also unifies the naming convention, now we have 3 handlers
- handle_lower_el_ea_esb
- handle_lower_el_sync_ea
- handle_lower_el_async_ea
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I63b584cf059bac80195aa334981d50fa6272cf49
Following hardening done around ESR_EL3 register usage
- Panic if exception is anyting other than SError
- AET bit is only valid if DFSC is 0x11, move DFSC check before AET.
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: Ib15159920f6cad964332fd40f88943aee2bc73b4
During a synchronous exception, the 'enter_lower_el_sync_ea' handler
tests the ESR_EL3 EA bit and calls 'report_unhandled_exception', if
it is not set.
EA = 0 and IFSC = SEA, seems to be a contradiction. EA provides further
classification of a synchronous abort. A synchronous abort is determined
by the IFSC value on an instruction fetch synchronous abort. As a result,
EA will never be set to 1 on an instruction fetch synchronous abort and
'report_unhandled_exception' should not be called.
This patch removes this behavior to allow the platform to handle the
exception.
Signed-off-by: Nicolas Benech <nbenech@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I3f004447ad4316d81649063e1ffb3ac644c83ede
During a transition to a higher EL some of the PSTATE bits are not set
by hardware, this means that their state may be leaked from lower ELs.
This patch sets those bits to a default value upon entry to EL3.
This patch was tested using a debugger to check the PSTATE values
are correctly set. As well as adding a test in the next patch to
ensure the PSTATE in lower ELs is still maintained after this change.
Change-Id: Ie546acbca7b9aa3c86bd68185edded91b2a64ae5
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
In the next patch we add an extra step of setting the PSTATE
registers to a known state on el3 entry. In this patch we create
the function prepare_el3_entry to wrap the steps needed for before
el3 entry. For now this is only save_gp_pmcr_pauth_regs.
Change-Id: Ie26dc8d89bfaec308769165d2649e84d41be196c
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
For SoCs which do not implement RAS, use DSB as a barrier to
synchronize pending external aborts at the entry and exit of
exception handlers. This is needed to isolate the SErrors to
appropriate context.
However, this introduces an unintended side effect as discussed
in the https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3440
A summary of the side effect and a quick workaround is provided as
part of this patch and summarized here:
The explicit DSB at the entry of various exception vectors in BL31
for handling exceptions from lower ELs can inadvertently trigger an
SError exception in EL3 due to pending asyncrhonouus aborts in lower
ELs. This will end up being handled by serror_sp_elx in EL3 which will
ultimately panic and die.
The way to workaround is to update a flag to indicate if the exception
truly came from EL3. This flag is allocated in the cpu_context
structure. This is not a bullet proof solution to the problem at hand
because we assume the instructions following "isb" that help to update
the flag (lines 100-102 & 139-141) execute without causing further
exceptions.
Change-Id: I4d345b07d746a727459435ddd6abb37fda24a9bf
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
EA handlers for exceptions taken from lower ELs at the end invokes
el3_exit function. However there was a bug with sp maintenance which
resulted in el3_exit setting runtime stack to context. This in turn
caused memory corruption on consecutive EL3 entries.
Signed-off-by: Jan Dabros <jsd@semihalf.com>
Change-Id: I0424245c27c369c864506f4baa719968890ce659
Coherent I-cache is causing a prefetch violation where when the core
executes an instruction that has recently been modified, the core might
fetch a stale instruction which violates the ordering of instruction
fetches.
The workaround includes an instruction sequence to implementation
defined registers to trap all EL0 IC IVAU instructions to EL3 and a trap
handler to execute a TLB inner-shareable invalidation to an arbitrary
address followed by a DSB.
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Change-Id: Ic3b7cbb11cf2eaf9005523ef5578a372593ae4d6
This patch provides the following features and makes modifications
listed below:
- Individual APIAKey key generation for each CPU.
- New key generation on every BL31 warm boot and TSP CPU On event.
- Per-CPU storage of APIAKey added in percpu_data[]
of cpu_data structure.
- `plat_init_apiakey()` function replaced with `plat_init_apkey()`
which returns 128-bit value and uses Generic timer physical counter
value to increase the randomness of the generated key.
The new function can be used for generation of all ARMv8.3-PAuth keys
- ARMv8.3-PAuth specific code placed in `lib\extensions\pauth`.
- New `pauth_init_enable_el1()` and `pauth_init_enable_el3()` functions
generate, program and enable APIAKey_EL1 for EL1 and EL3 respectively;
pauth_disable_el1()` and `pauth_disable_el3()` functions disable
PAuth for EL1 and EL3 respectively;
`pauth_load_bl31_apiakey()` loads saved per-CPU APIAKey_EL1 from
cpu-data structure.
- Combined `save_gp_pauth_registers()` function replaces calls to
`save_gp_registers()` and `pauth_context_save()`;
`restore_gp_pauth_registers()` replaces `pauth_context_restore()`
and `restore_gp_registers()` calls.
- `restore_gp_registers_eret()` function removed with corresponding
code placed in `el3_exit()`.
- Fixed the issue when `pauth_t pauth_ctx` structure allocated space
for 12 uint64_t PAuth registers instead of 10 by removal of macro
CTX_PACGAKEY_END from `include/lib/el3_runtime/aarch64/context.h`
and assigning its value to CTX_PAUTH_REGS_END.
- Use of MODE_SP_ELX and MODE_SP_EL0 macro definitions
in `msr spsel` instruction instead of hard-coded values.
- Changes in documentation related to ARMv8.3-PAuth and ARMv8.5-BTI.
Change-Id: Id18b81cc46f52a783a7e6a09b9f149b6ce803211
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
This patch fixes an issue when secure world timing information
can be leaked because Secure Cycle Counter is not disabled.
For ARMv8.5 the counter gets disabled by setting MDCR_El3.SCCD
bit on CPU cold/warm boot.
For the earlier architectures PMCR_EL0 register is saved/restored
on secure world entry/exit from/to Non-secure state, and cycle
counting gets disabled by setting PMCR_EL0.DP bit.
'include\aarch64\arch.h' header file was tided up and new
ARMv8.5-PMU related definitions were added.
Change-Id: I6f56db6bc77504634a352388990ad925a69ebbfa
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
The previous commit added the infrastructure to load and save
ARMv8.3-PAuth registers during Non-secure <-> Secure world switches, but
didn't actually enable pointer authentication in the firmware.
This patch adds the functionality needed for platforms to provide
authentication keys for the firmware, and a new option (ENABLE_PAUTH) to
enable pointer authentication in the firmware itself. This option is
disabled by default, and it requires CTX_INCLUDE_PAUTH_REGS to be
enabled.
Change-Id: I35127ec271e1198d43209044de39fa712ef202a5
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
ARMv8.3-PAuth adds functionality that supports address authentication of
the contents of a register before that register is used as the target of
an indirect branch, or as a load.
This feature is supported only in AArch64 state.
This feature is mandatory in ARMv8.3 implementations.
This feature adds several registers to EL1. A new option called
CTX_INCLUDE_PAUTH_REGS has been added to select if the TF needs to save
them during Non-secure <-> Secure world switches. This option must be
enabled if the hardware has the registers or the values will be leaked
during world switches.
To prevent leaks, this patch also disables pointer authentication in the
Secure world if CTX_INCLUDE_PAUTH_REGS is 0. Any attempt to use it will
be trapped in EL3.
Change-Id: I27beba9907b9a86c6df1d0c5bf6180c972830855
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@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>
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>
