Support for Mediatek MT6795 SoC ...

This patch support single core to boot to Linux kernel
through Trusted Firmware.
It also support 32 bit kernel and 64 bit kernel booting.

Automatically select initial xlation lookup level ...

Instead of hardcoding a level 1 table as the base translation level
table, let the code decide which level is the most appropriate given
the virtual address space size.

As the table granularity is 4 KB, this allows the code to select
level 0, 1 or 2 as base level for AArch64. This way, instead of
limiting the virtual address space width to 39-31 bits, widths of
48-25 bit can be used.

For AArch32, this change allows the code to select level 1 or 2
as the base translation level table and use virtual address space
width of 32-25 bits.

Also removed some unused definitions related to translation tables.

Fixes ARM-software/tf-issues#362

Change-Id: Ie3bb5d6d1a4730a26700b09827c79f37ca3cdb65

AArch32: Add API to invoke runtime service handler ...

This patch adds an API in runtime service framework to
invoke the registered handler corresponding to the SMC function
identifier. This is helpful for AArch32 because the number of
arguments required by the handler is more than registers
available as per AArch32 program calling conventions and
requires the use of stack. Hence this new API will do the
necessary argument setup and invoke the appropriate
handler. Although this API is primarily intended for AArch32,
it can be used for AArch64 as well.

Change-Id: Iefa15947fe5a1df55b0859886e677446a0fd7241

Move SIZE_FROM_LOG2_WORDS macro to utils.h ...

This patch moves the macro SIZE_FROM_LOG2_WORDS() defined in
`arch.h` to `utils.h` as it is utility macro.

Change-Id: Ia8171a226978f053a1ee4037f80142c0a4d21430

Introduce PSCI Library Interface ...

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

Refactor the xlat_tables library code ...

The AArch32 long descriptor format and the AArch64 descriptor format
correspond to each other which allows possible sharing of xlat_tables
library code between AArch64 and AArch32. This patch refactors the
xlat_tables library code to seperate the common functionality from
architecture specific code. Prior to this patch, all of the xlat_tables
library code were in `lib/aarch64/xlat_tables.c` file. The refactored code
is now in `lib/xlat_tables/` directory. The AArch64 specific programming
for xlat_tables is in `lib/xlat_tables/aarch64/xlat_tables.c` and the rest
of the code common to AArch64 and AArch32 is in
`lib/xlat_tables/xlat_tables_common.c`. Also the data types used in
xlat_tables library APIs are reworked to make it compatible between AArch64
and AArch32.

The `lib/aarch64/xlat_tables.c` file now includes the new xlat_tables
library files to retain compatibility for existing platform ports.
The macros related to xlat_tables library are also moved from
`include/lib/aarch64/arch.h` to the header `include/lib/xlat_tables.h`.

NOTE: THE `lib/aarch64/xlat_tables.c` FILE IS DEPRECATED AND PLATFORM PORTS
ARE EXPECTED TO INCLUDE THE NEW XLAT_TABLES LIBRARY FILES IN THEIR MAKEFILES.

Change-Id: I3d17217d24aaf3a05a4685d642a31d4d56255a0f

Merge pull request #577 from antonio-nino-diaz-arm/an/remove-xlat-helpers ...

Remove xlat_helpers.c

Remove xlat_helpers.c ...

lib/aarch64/xlat_helpers.c defines helper functions to build
translation descriptors, but no common code or upstream platform
port uses them. As the rest of the xlat_tables code evolves, there
may be conflicts with these helpers, therefore this code should be
removed.

Change-Id: I9f5be99720f929264818af33db8dada785368711

Add ISR_EL1 to crash report ...

Bring ISR bits definition as a mnemonic for troublershooters as well.

Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

Remove DAIF bits handling macros ...

These macros are unused and redundant with other CPU system registers
functions.

Moreover enable_serror() function implementation may not reach its purpose
because it does not handle the value of SCR_EL3.EA.

Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>

Extend memory attributes to map non-cacheable memory ...

At the moment, the memory translation library allows to create memory
mappings of 2 types:

 - Device nGnRE memory (named MT_DEVICE in the library);

 - Normal, Inner Write-back non-transient, Outer Write-back
   non-transient memory (named MT_MEMORY in the library).

As a consequence, the library code treats the memory type field as a
boolean: everything that is not device memory is normal memory and
vice-versa.

In reality, the ARMv8 architecture allows up to 8 types of memory to
be used at a single time for a given exception level. This patch
reworks the memory attributes such that the memory type is now defined
as an integer ranging from 0 to 7 instead of a boolean. This makes it
possible to extend the list of memory types supported by the memory
translation library.

The priority system dictating memory attributes for overlapping
memory regions has been extended to cope with these changes but the
algorithm at its core has been preserved. When a memory region is
re-mapped with different memory attributes, the memory translation
library examines the former attributes and updates them only if
the new attributes create a more restrictive mapping. This behaviour
is unchanged, only the manipulation of the value has been modified
to cope with the new format.

This patch also introduces a new type of memory mapping in the memory
translation library: MT_NON_CACHEABLE, meaning Normal, Inner
Non-cacheable, Outer Non-cacheable memory. This can be useful to map
a non-cacheable memory region, such as a DMA buffer for example.

The rules around the Execute-Never (XN) bit in a translation table
for an MT_NON_CACHEABLE memory mapping have been aligned on the rules
used for MT_MEMORY mappings:
 - If the memory is read-only then it is also executable (XN = 0);
 - If the memory is read-write then it is not executable (XN = 1).

The shareability field for MT_NON_CACHEABLE mappings is always set as
'Outer-Shareable'. Note that this is not strictly needed since
shareability is only relevant if the memory is a Normal Cacheable
memory type, but this is to align with the existing device memory
mappings setup. All Device and Normal Non-cacheable memory regions
are always treated as Outer Shareable, regardless of the translation
table shareability attributes.

This patch also removes the 'ATTR_SO' and 'ATTR_SO_INDEX' #defines.
They were introduced to map memory as Device nGnRnE (formerly called
"Strongly-Ordered" memory in the ARMv7 architecture) but were not
used anywhere in the code base. Removing them avoids any confusion
about the memory types supported by the library.

Upstream platforms do not currently use the MT_NON_CACHEABLE memory
type.

NOTE: THIS CHANGE IS SOURCE COMPATIBLE BUT PLATFORMS THAT RELY ON THE
BINARY VALUES OF `mmap_attr_t` or the `attr` argument of
`mmap_add_region()` MAY BE BROKEN.

Change-Id: I717d6ed79b4c845a04e34132432f98b93d661d79

ARM platforms: rationalise memory attributes of shared memory ...

The shared memory region on ARM platforms contains the mailboxes and,
on Juno, the payload area for communication with the SCP. This shared
memory may be configured as normal memory or device memory at build
time by setting the platform flag 'PLAT_ARM_SHARED_RAM_CACHED' (on
Juno, the value of this flag is defined by 'MHU_PAYLOAD_CACHED').
When set as normal memory, the platform port performs the corresponding
cache maintenance operations. From a functional point of view, this is
the equivalent of setting the shared memory as device memory, so there
is no need to maintain both options.

This patch removes the option to specify the shared memory as normal
memory on ARM platforms. Shared memory is always treated as device
memory. Cache maintenance operations are no longer needed and have
been replaced by data memory barriers to guarantee that payload and
MHU are accessed in the right order.

Change-Id: I7f958621d6a536dd4f0fa8768385eedc4295e79f

Initialize VTTBR_EL2 when bypassing EL2 ...

In the situation that EL1 is selected as the exception level for the
next image upon BL31 exit for a processor that supports EL2, the
context management code must configure all essential EL2 register
state to ensure correct execution of EL1.

VTTBR_EL2 should be part of this set of EL2 registers because:
 - The ARMv8-A architecture does not define a reset value for this
   register.
 - Cache maintenance operations depend on VTTBR_EL2.VMID even when
   non-secure EL1&0 stage 2 address translation are disabled.

This patch initializes the VTTBR_EL2 register to 0 when bypassing EL2
to address this issue. Note that this bug has not yet manifested
itself on FVP or Juno because VTTBR_EL2.VMID resets to 0 on the
Cortex-A53 and Cortex-A57.

Change-Id: I58ce2d16a71687126f437577a506d93cb5eecf33

Add ARM GICv3 driver without support for legacy operation ...

This patch adds a driver for ARM GICv3 systems that need to run software
stacks where affinity routing is enabled across all privileged exception
levels for both security states. This driver is a partial implementation
of the ARM Generic Interrupt Controller Architecture Specification, GIC
architecture version 3.0 and version 4.0 (ARM IHI 0069A). The driver does
not cater for legacy support of interrupts and asymmetric configurations.

The existing GIC driver has been preserved unchanged. The common code for
GICv2 and GICv3 systems has been refactored into a new file,
`drivers/arm/gic/common/gic_common.c`. The corresponding header is in
`include/drivers/arm/gic_common.h`.

The driver interface is implemented in `drivers/arm/gic/v3/gicv3_main.c`.
The corresponding header is in `include/drivers/arm/gicv3.h`. Helper
functions are implemented in `drivers/arm/gic/v3/arm_gicv3_helpers.c`
and are accessible through the `drivers/arm/gic/v3/gicv3_private.h`
header.

Change-Id: I8c3c834a1d049d05b776b4dcb76b18ccb927444a

Add missing RES1 bit in SCTLR_EL1 ...

As per Section D7.2.81 in the ARMv8-A Reference Manual (DDI0487A Issue A.h),
bits[29:28], bits[23:22], bit[20] and bit[11] in the SCTLR_EL1 are RES1. This
patch adds the missing bit[20] to the SCTLR_EL1_RES1 macro.

Change-Id: I827982fa2856d04def6b22d8200a79fe6922a28e

Make generic code work in presence of system caches ...

On the ARMv8 architecture, cache maintenance operations by set/way on the last
level of integrated cache do not affect the system cache. This means that such a
flush or clean operation could result in the data being pushed out to the system
cache rather than main memory. Another CPU could access this data before it
enables its data cache or MMU. Such accesses could be serviced from the main
memory instead of the system cache. If the data in the sysem cache has not yet
been flushed or evicted to main memory then there could be a loss of
coherency. The only mechanism to guarantee that the main memory will be updated
is to use cache maintenance operations to the PoC by MVA(See section D3.4.11
(System level caches) of ARMv8-A Reference Manual (Issue A.g/ARM DDI0487A.G).

This patch removes the reliance of Trusted Firmware on the flush by set/way
operation to ensure visibility of data in the main memory. Cache maintenance
operations by MVA are now used instead. The following are the broad category of
changes:

1. The RW areas of BL2/BL31/BL32 are invalidated by MVA before the C runtime is
   initialised. This ensures that any stale cache lines at any level of cache
   are removed.

2. Updates to global data in runtime firmware (BL31) by the primary CPU are made
   visible to secondary CPUs using a cache clean operation by MVA.

3. Cache maintenance by set/way operations are only used prior to power down.

NOTE: NON-UPSTREAM TRUSTED FIRMWARE CODE SHOULD MAKE EQUIVALENT CHANGES IN
ORDER TO FUNCTION CORRECTLY ON PLATFORMS WITH SUPPORT FOR SYSTEM CACHES.

Fixes ARM-software/tf-issues#205

Change-Id: I64f1b398de0432813a0e0881d70f8337681f6e9a

Remove use of PLATFORM_CACHE_LINE_SIZE ...

The required platform constant PLATFORM_CACHE_LINE_SIZE is
unnecessary since CACHE_WRITEBACK_GRANULE effectively provides the
same information. CACHE_WRITEBACK_GRANULE is preferred since this
is an architecturally defined term and allows comparison with the
corresponding hardware register value.

Replace all usage of PLATFORM_CACHE_LINE_SIZE with
CACHE_WRITEBACK_GRANULE.

Also, add a runtime assert in BL1 to check that the provided
CACHE_WRITEBACK_GRANULE matches the value provided in CTR_EL0.

Change-Id: If87286be78068424217b9f3689be358356500dcd

Merge pull request #280 from vwadekar/tlkd-fixed-v3 ...

TLK dispatcher

Translate secure/non-secure virtual addresses ...

This patch adds functionality to translate virtual addresses from
secure or non-secure worlds. This functionality helps Trusted Apps
to share virtual addresses directly and allows the NS world to
pass virtual addresses to TLK directly.

Change-Id: I77b0892963e0e839c448b5d0532920fb7e54dc8e
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

Use ARM CCI driver on FVP and Juno platforms ...

This patch updates the FVP and Juno platform ports to use the common
driver for ARM Cache Coherent Interconnects.

Change-Id: Ib142f456b9b673600592616a2ec99e9b230d6542

Return success if an interrupt is seen during PSCI CPU_SUSPEND ...

This patch adds support to return SUCCESS if a pending interrupt is
detected during a CPU_SUSPEND call to a power down state. The check
is performed as late as possible without losing the ability to return
to the caller. This reduces the overhead incurred by a CPU in
undergoing a complete power cycle when a wakeup interrupt is already
pending.

Fixes ARM-Software/tf-issues#102

Change-Id: I1aff04a74b704a2f529734428030d1d10750fd4b

Add macros for domain specific barriers. ...

This patch adds helper macros for barrier operations that specify
the type of barrier (dmb, dsb) and the shareability domain (system,
inner-shareable) it affects.

Change-Id: I4bf95103e79da212c4fbdbc13d91ad8ac385d9f5

Prevent optimisation of sysregs accessors calls ...

Calls to system register read accessors functions may be optimised
out by the compiler if called twice in a row for the same register.
This is because the compiler is not aware that the result from
the instruction may be modified by external agents. Therefore, if
nothing modifies the register between the 2 reads as far as the
compiler knows then it might consider that it is useless to read
it twice and emit only 1 call.

This behaviour is faulty for registers that may not have the same
value if read twice in succession. E.g.: counters, timer
control/countdown registers, GICv3 interrupt status registers and
so on.

The same problem happens for calls to system register write
accessors functions. The compiler might optimise out some calls
if it considers that it will produce the same result. Again, this
behaviour is faulty for cases where intermediate writes to these
registers make a difference in the system.

This patch fixes the problem by making these assembly register
accesses volatile.

Fixes ARM-software/tf-issues#273

Change-Id: I33903bc4cc4eea8a8d87bc2c757909fbb0138925

Fix the array size of mpidr_aff_map_nodes_t. ...

This patch fixes the array size of mpidr_aff_map_nodes_t which
was less by one element.

Fixes ARM-software/tf-issues#264

Change-Id: I48264f6f9e7046a3d0f4cbcd63b9ba49657e8818

Apply errata workarounds only when major/minor revisions match. ...

Prior to this patch, the errata workarounds were applied for any version
of the CPU in the release build and in the debug build an assert
failure resulted when the revision did not match. This patch applies
errata workarounds in the Cortex-A57 reset handler only if the 'variant'
and 'revision' fields read from the MIDR_EL1 match. In the debug build,
a warning message is printed for each errata workaround which is not
applied.

The patch modifies the register usage in 'reset_handler` so
as to adhere to ARM procedure calling standards.

Fixes ARM-software/tf-issues#242

Change-Id: I51b1f876474599db885afa03346e38a476f84c29

Merge pull request #206 from soby-mathew/sm/reset_cntvoff ...

Reset CNTVOFF_EL2 register before exit into EL1 on warm boot

Create BL stage specific translation tables ...

This patch uses the IMAGE_BL<x> constants to create translation tables specific
to a boot loader stage. This allows each stage to create mappings only for areas
in the memory map that it needs.

Fixes ARM-software/tf-issues#209

Change-Id: Ie4861407ddf9317f0fb890fc7575eaa88d0de51c

Initialize SCTLR_EL1 based on MODE_RW bit ...

Initializes SCTLR_EL1 based on MODE_RW bit in SPSR for the entry
point. The RES1 bits for SCTLR_EL1 differs for Aarch64 and Aarch32
mode.

Reset CNTVOFF_EL2 register before exit into EL1 on warm boot ...

This patch resets the value of CNTVOFF_EL2 before exit to EL1 on
warm boot. This needs to be done if only the Trusted Firmware exits
to EL1 instead of EL2, otherwise the hypervisor would be responsible
for this.

Fixes ARM-software/tf-issues#240

Change-Id: I79d54831356cf3215bcf1f251c373bd8f89db0e0

Juno: Implement initial platform port ...

This patch adds the initial port of the ARM Trusted Firmware on the Juno
development platform. This port does not support a BL3-2 image or any PSCI APIs
apart from PSCI_VERSION and PSCI_CPU_ON. It enables workarounds for selected
Cortex-A57 (#806969 & #813420) errata and implements the workaround for a Juno
platform errata (Defect id 831273).

Change-Id: Ib3d92df3af53820cfbb2977582ed0d7abf6ef893