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

Add support for selected Cortex-A57 errata workarounds ...

This patch adds workarounds for selected errata which affect the Cortex-A57 r0p0
part. Each workaround has a build time flag which should be used by the platform
port to enable or disable the corresponding workaround. The workarounds are
disabled by default. An assertion is raised if the platform enables a workaround
which does not match the CPU revision at runtime.

Change-Id: I9ae96b01c6ff733d04dc733bd4e67dbf77b29fb0

Add CPU specific crash reporting handlers ...

This patch adds handlers for dumping Cortex-A57 and Cortex-A53 specific register
state to the CPU specific operations framework. The contents of CPUECTLR_EL1 are
dumped currently.

Change-Id: I63d3dbfc4ac52fef5e25a8cf6b937c6f0975c8ab

Add CPU specific power management operations ...

This patch adds CPU core and cluster power down sequences to the CPU specific
operations framework introduced in a earlier patch. Cortex-A53, Cortex-A57 and
generic AEM sequences have been added. The latter is suitable for the
Foundation and Base AEM FVPs. A pointer to each CPU's operations structure is
saved in the per-cpu data so that it can be easily accessed during power down
seqeunces.

An optional platform API has been introduced to allow a platform to disable the
Accelerator Coherency Port (ACP) during a cluster power down sequence. The weak
definition of this function (plat_disable_acp()) does not take any action. It
should be overriden with a strong definition if the ACP is present on a
platform.

Change-Id: I8d09bd40d2f528a28d2d3f19b77101178778685d

Introduce framework for CPU specific operations ...

This patch introduces a framework which will allow CPUs to perform
implementation defined actions after a CPU reset, during a CPU or cluster power
down, and when a crash occurs. CPU specific reset handlers have been implemented
in this patch. Other handlers will be implemented in subsequent patches.

Also moved cpu_helpers.S to the new directory lib/cpus/aarch64/.

Change-Id: I1ca1bade4d101d11a898fb30fea2669f9b37b956

Simplify management of SCTLR_EL3 and SCTLR_EL1 ...

This patch reworks the manner in which the M,A, C, SA, I, WXN & EE bits of
SCTLR_EL3 & SCTLR_EL1 are managed. The EE bit is cleared immediately after reset
in EL3. The I, A and SA bits are set next in EL3 and immediately upon entry in
S-EL1. These bits are no longer managed in the blX_arch_setup() functions. They
do not have to be saved and restored either. The M, WXN and optionally the C
bit are set in the enable_mmu_elX() function. This is done during both the warm
and cold boot paths.

Fixes ARM-software/tf-issues#226

Change-Id: Ie894d1a07b8697c116960d858cd138c50bc7a069

Make enablement of the MMU more flexible ...

This patch adds a 'flags' parameter to each exception level specific function
responsible for enabling the MMU. At present only a single flag which indicates
whether the data cache should also be enabled is implemented. Subsequent patches
will use this flag when enabling the MMU in the warm boot paths.

Change-Id: I0eafae1e678c9ecc604e680851093f1680e9cefa

Calculate TCR bits based on VA and PA ...

Currently the TCR bits are hardcoded in xlat_tables.c. In order to
map higher physical address into low virtual address, the TCR bits
need to be configured accordingly.

This patch is to save the max VA and PA and calculate the TCR.PS/IPS
and t0sz bits in init_xlat_tables function.

Change-Id: Ia7a58e5372b20200153057d457f4be5ddbb7dae4

Remove all checkpatch errors from codebase ...

Exclude stdlib files because they do not follow kernel code style.

Fixes ARM-software/tf-issues#73

Change-Id: I4cfafa38ab436f5ab22c277cb38f884346a267ab

Initialise CPU contexts from entry_point_info ...

Consolidate all BL3-1 CPU context initialization for cold boot, PSCI
and SPDs into two functions:
*  The first uses entry_point_info to initialize the relevant
   cpu_context for first entry into a lower exception level on a CPU
*  The second populates the EL1 and EL2 system registers as needed
   from the cpu_context to ensure correct entry into the lower EL

This patch alters the way that BL3-1 determines which exception level
is used when first entering EL1 or EL2 during cold boot - this is now
fully determined by the SPSR value in the entry_point_info for BL3-3,
as set up by the platform code in BL2 (or otherwise provided to BL3-1).

In the situation that EL1 (or svc mode) is selected for a processor
that supports EL2, the context management code will now configure all
essential EL2 register state to ensure correct execution of EL1. This
allows the platform code to run non-secure EL1 payloads directly
without requiring a small EL2 stub or OS loader.

Change-Id: If9fbb2417e82d2226e47568203d5a369f39d3b0f

Merge pull request #130 from athoelke/at/inline-asm-sysreg-v2 ...

Make system register functions inline assembly v2

Make system register functions inline assembly ...

Replace the current out-of-line assembler implementations of
the system register and system instruction operations with
inline assembler.

This enables better compiler optimisation and code generation
when accessing system registers.

Fixes ARM-software/tf-issues#91

Change-Id: I149af3a94e1e5e5140a3e44b9abfc37ba2324476

Enable mapping higher physical address ...

Current ATF uses a direct physical-to-virtual mapping, that is, a physical
address is mapped to the same address in the virtual space. For example,
physical address 0x8000_0000 is mapped to 0x8000_0000 virtual. This
approach works fine for FVP as all its physical addresses fall into 0 to
4GB range. But for other platform where all I/O addresses are 48-bit long,
If we follow the same direct mapping, we would need virtual address range
from 0 to 0x8fff_ffff_ffff, which is about 144TB. This requires a
significant amount of memory for MMU tables and it is not necessary to use
that much virtual space in ATF.

The patch is to enable mapping a physical address range to an arbitrary
virtual address range (instead of flat mapping)
Changed "base" to "base_va" and added "base_pa" in mmap_region_t and
modified functions such as mmap_add_region and init_xlation_table etc.
Fixes ARM-software/tf-issues#158