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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>

The intention of this patch is to leverage the existing el3_exit() return
routine for smc_unknown return path rather than a custom set of instructions.
In order to leverage el3_exit(), the necessary counteraction (i.e., saving the
system registers apart from GP registers) must be performed. Hence a series of
instructions which save system registers( like SPSR_EL3, SCR_EL3 etc) to stack
are moved to the top of group of instructions which essentially decode the OEN
from the smc function identifier and obtain the specific service handler in
rt_svc_descs_array. This ensures that the control flow for both known and
unknown smc calls will be similar.

Change-Id: I67f94cfcba176bf8aee1a446fb58a4e383905a87
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>

Replace call to pauth_context_save() with pauth_context_restore()
in case of unknown SMC call.

Change-Id: Ib863d979faa7831052b33e8ac73913e2f661f9a0
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>

The relocation fixup code must be called at the beginning of bl31
entrypoint to ensure that CPU specific reset handlers are fixed up for
relocations.

Change-Id: Icb04eacb2d4c26c26b08b768d871d2c82777babb
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>

Change-Id: I8fb346743b7afddbb8bf5908db4f27ee5a26f99b
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>

In the current Pointer Authentication support added in
commit b86048c4


PAuth gets enabled in BL31 cold boot entrypoint only,
(see bl31_entrypoint() in bl31\aarch64\bl31_entrypoint.S)
but not in bl31_warm_entrypoint().
This results in EnIA bit [31] in SCTLR_EL3 not being set
and pointer authentication disabled after CPU wake-up event.

Fixes ARM-software/tf-issues#684

Change-Id: I27a67804764dfba2a6d72ca119ca2bcff4f536d6
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>

The size increase after enabling options related to ARMv8.3-PAuth is:

+----------------------------+-------+-------+-------+--------+
|                            |  text |  bss  |  data | rodata |
+----------------------------+-------+-------+-------+--------+
| CTX_INCLUDE_PAUTH_REGS = 1 |  +192 | +1536 |   +0  |   +0   |
|                            |  0.3% |  3.1% |       |        |
+----------------------------+-------+-------+-------+--------+
| ENABLE_PAUTH = 1           | +1848 | +1536 |  +16  |   +0   |
|                            |  3.3% |  3.1% |  3.1% |        |
+----------------------------+-------+-------+-------+--------+

Results calculated with the following build configuration:

    make PLAT=fvp SPD=tspd DEBUG=1 \
    SDEI_SUPPORT=1                 \
    EL3_EXCEPTION_HANDLING=1       \
    TSP_NS_INTR_ASYNC_PREEMPT=1    \
    CTX_INCLUDE_PAUTH_REGS=1       \
    ENABLE_PAUTH=1

Change-Id: I43db7e509a4f39da6599ec2faa690d197573ec1b
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@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>

This reverts commit 2f370465

 ("Add support for the SMC Calling
Convention 2.0").

SMCCC v2.0 is no longer required for SPM, and won't be needed in the
future. Removing it makes the SMC handling code less complicated.

The SPM implementation based on SPCI and SPRT was using it, but it has
been adapted to SMCCC v1.0.

Change-Id: I36795b91857b2b9c00437cfbfed04b3c1627f578
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: e0ea0928 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca339

 ("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>

Change-Id: I2ae9b3bb686c41b2e138132a7bed107925ac861e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Use the helper function `save_gp_registers` to save the register
state to cpu_context on entry to EL3 in SMC handler. This has the
effect of saving x0 - x3 as well into the cpu_context which was
not done previously but it unifies the register save sequence
in BL31.

Change-Id: I5753c942263a5f9178deda3dba896e3220f3dd83
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

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>

No functional changes.

Change-Id: I9638e02acb9b22eb794ebf45aad84348a710287e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

External Aborts while executing in EL3 is fatal in nature. This patch
allows for the platform to define a handler for External Aborts received
while executing in EL3. A default implementation is added which falls
back to platform unhandled exception.

Change-Id: I466f2c8113a33870f2c7d2d8f2bf20437d9fd354
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@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>

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>