Fix MISRA defects in BL31 common code ...

Change-Id: I5993b425445ee794e6d2a792c244c0af53640655
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Merge pull request #1532 from jeenu-arm/misra-fixes ...

MISRA fixes

Merge pull request #1533 from jeenu-arm/mpam ...

AArch64: Enable MPAM for lower ELs

EHF: MISRA fixes ...

These changes address most of the required MISRA rules. In the process,
some from generic code are also fixed.

No functional changes.

Change-Id: I19786070af7bc5e1f6d15bdba93e22a4451d8fe9
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

AArch64: Enable MPAM for lower ELs ...

Memory Partitioning And Monitoring is an Armv8.4 feature that enables
various memory system components and resources to define partitions.
Software running at various ELs can then assign themselves to the
desired partition to control their performance aspects.

With this patch, when ENABLE_MPAM_FOR_LOWER_ELS is set to 1, EL3 allows
lower ELs to access their own MPAM registers without trapping to EL3.
This patch however doesn't make use of partitioning in EL3; platform
initialisation code should configure and use partitions in EL3 if
required.

Change-Id: I5a55b6771ccaa0c1cffc05543d2116b60cbbcdcd
Co-authored-by: James Morse <james.morse@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

DSU erratum 936184 workaround ...

If the system is in near idle conditions, this erratum could cause a
deadlock or data corruption. This patch applies the workaround that
prevents this.

This DSU erratum affects only the DSUs that contain the ACP interface
and it was fixed in r2p0. The workaround is applied only to the DSUs
that are actually affected.

Link to respective Arm documentation:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.epm138168/index.html

Change-Id: I033213b3077685130fc1e3f4f79c4d15d7483ec9
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

RAS: Introduce handler for EL3 EAs ...

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>

RAS: Introduce handler for Double Faults ...

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>

RAS: Introduce handler for Uncontainable errors ...

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: Validate stack pointer after error handling ...

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>

RAS: Move EA handling to a separate file ...

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>

Add end_vector_entry assembler macro ...

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>

Use ALIGN instead of NEXT in linker scripts ...

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>

DynamIQ: Enable MMU without using stack ...

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>

SDEI: Make dispatches synchronous ...

SDEI event dispatches currently only sets up the Non-secure context
before returning to the caller. The actual dispatch only happens upon
exiting EL3 next time.

However, for various error handling scenarios, it's beneficial to have
the dispatch happen synchronously. I.e. when receiving SDEI interrupt,
or for a successful sdei_dispatch_event() call, the event handler is
executed; and upon the event completion, dispatcher execution resumes
after the point of dispatch. The jump primitives introduced in the
earlier patch facilitates this feature.

With this patch:

  - SDEI interrupts and calls to sdei_dispatch_event prepares the NS
    context for event dispatch, then sets a jump point, and immediately
    exits EL3. This results in the client handler executing in
    Non-secure.

  - When the SDEI client completes the dispatched event, the SDEI
    dispatcher does a longjmp to the jump pointer created earlier. For
    the caller of the sdei_dispatch_event() in particular, this would
    appear as if call returned successfully.

The dynamic workaround for CVE_2018_3639 is slightly shifted around as
part of related minor refactoring. It doesn't affect the workaround
functionality.

Documentation updated.

NOTE: This breaks the semantics of the explicit dispatch API, and any
exiting usages should be carefully reviewed.

Change-Id: Ib9c876d27ea2af7fb22de49832e55a0da83da3f9
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

BL31: Introduce jump primitives ...

This patch introduces setjmp() and ongjmp() primitives to enable
standard setjmp/longjmp style execution. Both APIs parameters take a
pointer to struct jmpbuf type, which hosts CPU registers saved/restored
during jump.

As per the standard usage:

  - setjmp() return 0 when a jump is setup; and a non-zero value when
    returning from jump.

  - The caller of setjmp() must not return, or otherwise update stack
    pointer since.

Change-Id: I4af1d32e490cfa547979631b762b4cba188d0551
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

SPM: Treat SP xlat tables the same as others ...

The translation tables allocated for the Secure Partition do not need
to be treated as a special case. They can be put amongst the other
tables mapping BL31's general purpose memory. They will be mapped with
the same attributes as them, which is fine.

The explicit alignment constraint in BL31's linker script to pad the
last page of memory allocated to the Secure Partition's translation
tables is useless too, as page tables are per se pages, thus their
end address is naturally aligned on a page-boundary.

In fact, this patch does not change the existing behaviour. Since
patch 22282bb68a31 ("SPM: Move all SP-related info to SP context
struct"), the secure_partition.c file has been renamed into sp_xlat.c
but the linker script has not been properly updated. As a result, the
SP translation tables are not specifically put at the start of the
xlat_table linker section, the __SP_IMAGE_XLAT_TABLES_START__/_END__
symbols have the same value, the size of the resulting mmap_region
covering these xlat tables is 0 and so it is ignored.

Change-Id: I4cf0a4cc090298811cca53fc9cee74df0f2b1512
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

Rename symbols and files relating to CVE-2017-5715 ...

This patch renames symbols and files relating to CVE-2017-5715 to make
it easier to introduce new symbols and files for new CVE mitigations.

Change-Id: I24c23822862ca73648c772885f1690bed043dbc7
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

AArch64: Introduce RAS handling ...

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>

AArch64: Introduce External Abort handling ...

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>

AArch64: Refactor GP register restore to separate function ...

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>

Add support for the SMC Calling Convention 2.0 ...

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>

Fixup `SMCCC_ARCH_FEATURES` semantics ...

When querying `SMCCC_ARCH_WORKAROUND_1` through `SMCCC_ARCH_FEATURES`,
return either:
  * -1 to indicate the PE on which `SMCCC_ARCH_FEATURES` is called
    requires firmware mitigation for CVE-2017-5715 but the mitigation
    is not compiled in.
  * 0 to indicate that firmware mitigation is required, or
  * 1 to indicate that no firmware mitigation is required.

This patch complies with v1.2 of the firmware interfaces
specification (ARM DEN 0070A).

Change-Id: Ibc32d6620efdac6c340758ec502d95554a55f02a
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>

Suppress spurious deprecated declaration warnings ...

Some generic compatibility functions emit deprecated declaration warnings
even when platforms do not use the deprecated functions directly. This
can be confusing. Suppress these warnings by using:
`#pragma GCC diagnostic ignored "-Wdeprecated-declarations"`

Also emit a runtime warning if the weak plat/common implemntation of
plat_get_syscnt_freq2() is used, as this implies the platform has not
migrated from plat_get_syscnt_freq(). The deprecated  declaration warnings
only help detect when platforms are calling deprecated functions, not when
they are defining deprecated functions.

Fixes ARM-software/tf-issues#550

Change-Id: Id14a92279c2634c1e76db8ef210da8affdbb2a5d
Signed-off-by: Dan Handley <dan.handley@arm.com>

Merge pull request #1282 from robertovargas-arm/misra-changes ...

Misra changes

Fix MISRA rule 8.4 in common code ...

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>

Fix MISRA rule 8.3 in common code ...

Rule 8.3: All declarations of an object or function shall
          use the same names and type qualifiers.

Change-Id: Iff384187c74a598a4e73f350a1893b60e9d16cec
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

Merge pull request #1286 from antonio-nino-diaz-arm/an/mmu-mismatch ...

Clarify comments in xlat tables lib and fixes related to the TLB

Merge pull request #1284 from jeenu-arm/tspd-ehf ...

TSPD and EHF

EHF: Introduce preempted return code parameter to ehf_allow_ns_preemption() ...

When a Yielding SMC is preempted, it's possible that Non-secure world is
resumed afterwards. In this case, Non-secure execution would find itself
in a state where the SMC has returned. However, the dispatcher might not
get an opportunity to populate the corrected return code for having
been preempted, and therefore the caller of the Yielding SMC cannot
reliably determine whether the SMC had successfully completed or had
been preempted.

To solve this, this patch introduces a new parameter to the
ehf_allow_ns_preemption() API. An SPD, through this parameter, would
provide the expected error code when a Yielding SMC is preempted. EHF
can then populate the specified value in x0 of the Non-secure context so
that the caller of the Yielding SMC correctly identifies the SMC return
as a preemption.

Documentation updates to follow.

Change-Id: Ia9c3f8f03f9d72d81aa235eaae2ee0374b972e1e
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>