Workaround for CVE-2017-5715 for Cortex A9, A15 and A17 ...

A per-cpu vbar is installed that implements the workaround by
invalidating the branch target buffer (BTB) directly in the case of A9
and A17 and indirectly by invalidating the icache in the case of A15.

For Cortex A57 and A72 there is currently no workaround implemented
when EL3 is in AArch32 mode so report it as missing.

For other vulnerable CPUs (e.g. Cortex A73 and Cortex A75), there are
no changes since there is currently no upstream AArch32 EL3 support
for these CPUs.

Change-Id: Ib42c6ef0b3c9ff2878a9e53839de497ff736258f
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

sp_min: Implement workaround for CVE-2017-5715 ...

This patch introduces two workarounds for ARMv7 systems.  The
workarounds need to be applied prior to any `branch` instruction in
secure world.  This is achieved using a custom vector table where each
entry is an `add sp, sp, #1` instruction.

On entry to monitor mode, once the sequence of `ADD` instructions is
executed, the branch target buffer (BTB) is invalidated.  The bottom
bits of `SP` are then used to decode the exception entry type.

A side effect of this change is that the exception vectors are
installed before the CPU specific reset function.  This is now
consistent with how it is done on AArch64.

Note, on AArch32 systems, the exception vectors are typically tightly
integrated with the secure payload (e.g. the Trusted OS).  This
workaround will need porting to each secure payload that requires it.

The patch to modify the AArch32 per-cpu vbar to the corresponding
workaround vector table according to the CPU type will be done in a
later patch.

Change-Id: I5786872497d359e496ebe0757e8017fa98f753fa
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

bl2-el3: Add BL2_EL3 image ...

This patch enables BL2 to execute at the highest exception level
without any dependancy on TF BL1. This enables platforms which already
have a non-TF Boot ROM to directly load and execute BL2 and subsequent BL
stages without need for BL1.  This is not currently possible because
BL2 executes at S-EL1 and cannot jump straight to EL3.

Change-Id: Ief1efca4598560b1b8c8e61fbe26d1f44e929d69
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

utils: rename struct mem_region_t to struct mem_region ...

typedef mem_region_t mem_region_t;

... seems to work because they belong to different name-spaces,
but humans are confused even if compilers are not.

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

Merge pull request #1197 from dp-arm/dp/amu ...

AMUv1 support

Add hooks to save/restore AMU context for Cortex A75 ...

Change-Id: I504d3f65ca5829bc1f4ebadb764931f8379ee81f
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

AMU: Add hooks to save/restore AMU context ...

On some systems, the AMU counters might reset to 0 when a CPU
powerdown happens.  This behaviour conflicts with the intended
use-case of AMU as lower ELs are only expected to see non-decreasing
counter values.

Change-Id: If25519965d4e6e47e09225d0e732947986cbb5ec
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

AMU: Add configuration helpers for aarch64 ...

Add some AMU helper functions to allow configuring, reading and
writing of the Group 0 and Group 1 counters.  Documentation for these
helpers will come in a separate patch.

Change-Id: I656e070d2dae830c22414f694aa655341d4e2c40
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

AMU: Add plat interface to select which group 1 counters to enable ...

A new platform macro `PLAT_AMU_GROUP1_COUNTERS_MASK` controls which
group 1 counters should be enabled. The maximum number of group 1
counters supported by AMUv1 is 16 so the mask can be at most 0xffff.
If the platform does not define this mask, no group 1 counters are
enabled.

A related platform macro `PLAT_AMU_GROUP1_NR_COUNTERS` is used by
generic code to allocate an array to save and restore the counters on
CPU suspend.

Change-Id: I6d135badf4846292de931a43bb563077f42bb47b
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Add PubSub events for CPU powerdown/powerup ...

The suspend hook is published at the start of a CPU powerdown
operation.  The resume hook is published at the end of a CPU powerup
operation.

Change-Id: I50c05e2dde0d33834095ac41b4fcea4c161bb434
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Use PFR0 to identify need for mitigation of CVE-2017-5915 ...

If the CSV2 field reads as 1 then branch targets trained in one
context cannot affect speculative execution in a different context.
In that case skip the workaround on Cortex A75.

Change-Id: I4d5504cba516a67311fb5f0657b08f72909cbd38
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Workaround for CVE-2017-5715 on Cortex A73 and A75 ...

Invalidate the Branch Target Buffer (BTB) on entry to EL3 by
temporarily dropping into AArch32 Secure-EL1 and executing the
`BPIALL` instruction.

This is achieved by using 3 vector tables.  There is the runtime
vector table which is used to handle exceptions and 2 additional
tables which are required to implement this workaround.  The
additional tables are `vbar0` and `vbar1`.

The sequence of events for handling a single exception is
as follows:

1) Install vector table `vbar0` which saves the CPU context on entry
   to EL3 and sets up the Secure-EL1 context to execute in AArch32 mode
   with the MMU disabled and I$ enabled.  This is the default vector table.

2) Before doing an ERET into Secure-EL1, switch vbar to point to
   another vector table `vbar1`.  This is required to restore EL3 state
   when returning from the workaround, before proceeding with normal EL3
   exception handling.

3) While in Secure-EL1, the `BPIALL` instruction is executed and an
   SMC call back to EL3 is performed.

4) On entry to EL3 from Secure-EL1, the saved context from step 1) is
   restored.  The vbar is switched to point to `vbar0` in preparation to
   handle further exceptions.  Finally a branch to the runtime vector
   table entry is taken to complete the handling of the original
   exception.

This workaround is enabled by default on the affected CPUs.

NOTE
====

There are 4 different stubs in Secure-EL1.  Each stub corresponds to
an exception type such as Sync/IRQ/FIQ/SError.  Each stub will move a
different value in `R0` before doing an SMC call back into EL3.
Without this piece of information it would not be possible to know
what the original exception type was as we cannot use `ESR_EL3` to
distinguish between IRQs and FIQs.

Change-Id: I90b32d14a3735290b48685d43c70c99daaa4b434
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

utils_def: Add REGSZ and make BIT() assembly-compatible ...

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>

Merge pull request #1178 from davidcunado-arm/dc/enable_sve ...

Enable SVE for Non-secure world

SPM: Move S-EL1/S-EL0 xlat tables to TZC DRAM ...

A new platform define, `PLAT_SP_IMAGE_XLAT_SECTION_NAME`, has been
introduced to select the section where the translation tables used by
the S-EL1/S-EL0 are placed.

This define has been used to move the translation tables to DRAM secured
by TrustZone.

Most of the extra needed space in BL31 when SPM is enabled is due to the
large size of the translation tables. By moving them to this memory
region we can save 44 KiB.

A new argument has been added to REGISTER_XLAT_CONTEXT2() to specify the
region where the translation tables have to be placed by the linker.

Change-Id: Ia81709b4227cb8c92601f0caf258f624c0467719
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Enable SVE for Non-secure world ...

This patch adds a new build option, ENABLE_SVE_FOR_NS, which when set
to one EL3 will check to see if the Scalable Vector Extension (SVE) is
implemented when entering and exiting the Non-secure world.

If SVE is implemented, EL3 will do the following:

- Entry to Non-secure world: SIMD, FP and SVE functionality is enabled.

- Exit from Non-secure world: SIMD, FP and SVE functionality is
  disabled. As SIMD and FP registers are part of the SVE Z-registers
  then any use of SIMD / FP functionality would corrupt the SVE
  registers.

The build option default is 1. The SVE functionality is only supported
on AArch64 and so the build option is set to zero when the target
archiecture is AArch32.

This build option is not compatible with the CTX_INCLUDE_FPREGS - an
assert will be raised on platforms where SVE is implemented and both
ENABLE_SVE_FOR_NS and CTX_INCLUDE_FPREGS are set to 1.

Also note this change prevents secure world use of FP&SIMD registers on
SVE-enabled platforms. Existing Secure-EL1 Payloads will not work on
such platforms unless ENABLE_SVE_FOR_NS is set to 0.

Additionally, on the first entry into the Non-secure world the SVE
functionality is enabled and the SVE Z-register length is set to the
maximum size allowed by the architecture. This includes the use case
where EL2 is implemented but not used.

Change-Id: Ie2d733ddaba0b9bef1d7c9765503155188fe7dae
Signed-off-by: David Cunado <david.cunado@arm.com>

AMU: Implement support for aarch32 ...

The `ENABLE_AMU` build option can be used to enable the
architecturally defined AMU counters.  At present, there is no support
for the auxiliary counter group.

Change-Id: Ifc7532ef836f83e629f2a146739ab61e75c4abc8
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

AMU: Implement support for aarch64 ...

The `ENABLE_AMU` build option can be used to enable the
architecturally defined AMU counters.  At present, there is no support
for the auxiliary counter group.

Change-Id: I7ea0c0a00327f463199d1b0a481f01dadb09d312
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Implement support for the Activity Monitor Unit on Cortex A75 ...

The Cortex A75 has 5 AMU counters.  The first three counters are fixed
and the remaining two are programmable.

A new build option is introduced, `ENABLE_AMU`.  When set, the fixed
counters will be enabled for use by lower ELs.  The programmable
counters are currently disabled.

Change-Id: I4bd5208799bb9ed7d2596e8b0bfc87abbbe18740
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Merge pull request #1145 from etienne-lms/rfc-armv7-2 ...

Support ARMv7 architectures

Merge pull request #1163 from antonio-nino-diaz-arm/an/parange ...

Add ARMv8.2 ID_AA64MMFR0_EL1.PARange value

Refactor Statistical Profiling Extensions implementation ...

Factor out SPE operations in a separate file.  Use the publish
subscribe framework to drain the SPE buffers before entering secure
world.  Additionally, enable SPE before entering normal world.

A side effect of this change is that the profiling buffers are now
only drained when a transition from normal world to secure world
happens.  Previously they were drained also on return from secure
world, which is unnecessary as SPE is not supported in S-EL1.

Change-Id: I17582c689b4b525770dbb6db098b3a0b5777b70a
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Add ARMv8.2 ID_AA64MMFR0_EL1.PARange value ...

If an implementation of ARMv8.2 includes ARMv8.2-LPA, the value 0b0110
is permitted in ID_AA64MMFR0_EL1.PARange, which means that the Physical
Address range supported is 52 bits (4 PiB). It is a reserved value
otherwise.

Change-Id: Ie0147218e9650aa09f0034a9ee03c1cca8db908a
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Move FPEXC32_EL2 to FP Context ...

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>

ARM platforms: Provide SDEI entry point validation ...

Provide a strong definition for plat_sdei_validate_sdei_entrypoint()
which translates client address to Physical Address, and then validating
the address to be present in DRAM.

Change-Id: Ib93eb66b413d638aa5524d1b3de36aa16d38ea11
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

BL31: Introduce Exception Handling Framework ...

EHF is a framework that allows dispatching of EL3 interrupts to their
respective handlers in EL3.

This framework facilitates the firmware-first error handling policy in
which asynchronous exceptions may be routed to EL3. Such exceptions may
be handed over to respective exception handlers. Individual handlers
might further delegate exception handling to lower ELs.

The framework associates the delegated execution to lower ELs with a
priority value. For interrupts, this corresponds to the priorities
programmed in GIC; for other types of exceptions, viz. SErrors or
Synchronous External Aborts, individual dispatchers shall explicitly
associate delegation to a secure priority. In order to prevent lower
priority interrupts from preempting higher priority execution, the
framework provides helpers to control preemption by virtue of
programming Priority Mask register in the interrupt controller.

This commit allows for handling interrupts targeted at EL3. Exception
handlers own interrupts by assigning them a range of secure priorities,
and registering handlers for each priority range it owns.

Support for exception handling in BL31 image is enabled by setting the
build option EL3_EXCEPTION_HANDLING=1.

Documentation to follow.

NOTE: The framework assumes the priority scheme supported by platform
interrupt controller is compliant with that of ARM GIC architecture (v2
or later).

Change-Id: I7224337e4cea47c6ca7d7a4ca22a3716939f7e42
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Merge pull request #1148 from antonio-nino-diaz-arm/an/spm ...

Introduce Secure Partition Manager

SPM: Introduce Secure Partition Manager ...

A Secure Partition is a software execution environment instantiated in
S-EL0 that can be used to implement simple management and security
services. Since S-EL0 is an unprivileged exception level, a Secure
Partition relies on privileged firmware e.g. ARM Trusted Firmware to be
granted access to system and processor resources. Essentially, it is a
software sandbox that runs under the control of privileged software in
the Secure World and accesses the following system resources:

- Memory and device regions in the system address map.
- PE system registers.
- A range of asynchronous exceptions e.g. interrupts.
- A range of synchronous exceptions e.g. SMC function identifiers.

A Secure Partition enables privileged firmware to implement only the
absolutely essential secure services in EL3 and instantiate the rest in
a partition. Since the partition executes in S-EL0, its implementation
cannot be overly complex.

The component in ARM Trusted Firmware responsible for managing a Secure
Partition is called the Secure Partition Manager (SPM). The SPM is
responsible for the following:

- Validating and allocating resources requested by a Secure Partition.
- Implementing a well defined interface that is used for initialising a
  Secure Partition.
- Implementing a well defined interface that is used by the normal world
  and other secure services for accessing the services exported by a
  Secure Partition.
- Implementing a well defined interface that is used by a Secure
  Partition to fulfil service requests.
- Instantiating the software execution environment required by a Secure
  Partition to fulfil a service request.

Change-Id: I6f7862d6bba8732db5b73f54e789d717a35e802f
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Co-authored-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
Co-authored-by: Achin Gupta <achin.gupta@arm.com>
Co-authored-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

xlat: Make function to calculate TCR PA bits public ...

This function can be useful to setup TCR_ELx by callers that don't use
the translation tables library to setup the system registers related
to them. By making it common, it can be reused whenever it is needed
without duplicating code.

Change-Id: Ibfada9e846d2a6cd113b1925ac911bb27327d375
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

aarch32: add missing dmb() macro ...

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>