Enable Debug and SError exceptions on warm boot path ...

Enable Debug and SError exceptions:
 - when receiving an SMC;
 - when a CPU is physically powered up (upon resumption from suspend
   or in response to a PSCI cpu_on call)

Change-Id: I7e5613e34034be6ed68ec9e2aef4de66aa5ac65e

Fix compilation issue for IMF_READ_INTERRUPT_ID build flag ...

This patch fixes the compilation issue for trusted firmware when the
IMF_READ_INTERRUPT_ID is enabled.

Change-Id: I94ab613b9bc96a7c1935796c674dc42246aaafee

Merge pull request #110 from soby-mathew:sm/support_normal_irq_in_tsp-v4 into for-v0.4

Further renames of platform porting functions ...

Rename the ic_* platform porting functions to plat_ic_* to be
consistent with the other functions in platform.h. Also rename
bl31_get_next_image_info() to bl31_plat_get_next_image_ep_info()
and remove the duplicate declaration in bl31.h.

Change-Id: I4851842069d3cff14c0a468daacc0a891a7ede84

Fixup Standard SMC Resume Handling ...

This patch fixes a missed return and code alignment issues
in TSP_FID_RESUME handling.

Change-Id: Icf8aeb76dfd6898745653ce039e3bac45e0a9b3a

Add enable mmu platform porting interfaces ...

Previously, the enable_mmu_elX() functions were implicitly part of
the platform porting layer since they were included by generic
code. These functions have been placed behind 2 new platform
functions, bl31_plat_enable_mmu() and bl32_plat_enable_mmu().
These are weakly defined so that they can be optionally overridden
by platform ports.

Also, the enable_mmu_elX() functions have been moved to
lib/aarch64/xlat_tables.c for optional re-use by platform ports.
These functions are tightly coupled with the translation table
initialization code.

Fixes ARM-software/tf-issues#152

Change-Id: I0a2251ce76acfa3c27541f832a9efaa49135cc1c

Split platform.h into separate headers ...

Previously, platform.h contained many declarations and definitions
used for different purposes. This file has been split so that:

* Platform definitions used by common code that must be defined
  by the platform are now in platform_def.h. The exact include
  path is exported through $PLAT_INCLUDES in the platform makefile.

* Platform definitions specific to the FVP platform are now in
  /plat/fvp/fvp_def.h.

* Platform API declarations specific to the FVP platform are now
  in /plat/fvp/fvp_private.h.

* The remaining platform API declarations that must be ported by
  each platform are still in platform.h but this file has been
  moved to /include/plat/common since this can be shared by all
  platforms.

Change-Id: Ieb3bb22fbab3ee8027413c6b39a783534aee474a

Remove unused data declarations ...

Some data variables were declared but not used. These have been
removed.

Change-Id: I038632af3c32d88984cd25b886c43ff763269bf9

Remove extern keyword from function declarations ...

Function declarations implicitly have external linkage so do not
need the extern keyword.

Change-Id: Ia0549786796d8bf5956487e8996450a0b3d79f32

Merge pull request #104 from athoelke:at/tsp-entrypoints-v2

Merge pull request #105 from athoelke:sm/support_normal_irq_in_tsp-v2

Merge pull request #102 from achingupta:ag/tf-issues#104-v2

Merge pull request #99 from vikramkanigiri:vk/tf-issues-133_V3

Merge pull request #67 from achingupta:ag/psci_standby_bug_fix

Use a vector table for TSP entrypoints ...

The TSP has a number of entrypoints used by the TSP on different
occasions. These were provided to the TSPD as a table of function
pointers, and required the TSPD to read the entry in the table,
which is in TSP memory, in order to program the exception return
address.

Ideally, the TSPD has no access to the TSP memory.

This patch changes the table of function pointers into a vector
table of single instruction entrypoints. This allows the TSPD to
calculate the entrypoint address instead of read it.

Fixes ARM-software/tf-issues#160

Change-Id: Iec6e055d537ade78a45799fbc6f43765a4725ad3

Non-Secure Interrupt support during Standard SMC processing in TSP ...

Implements support for Non Secure Interrupts preempting the
Standard SMC call in EL1. Whenever an IRQ is trapped in the
Secure world we securely handover to the Normal world
to process the interrupt. The normal world then issues
"resume" smc call to resume the previous interrupted SMC call.
Fixes ARM-software/tf-issues#105

Change-Id: I72b760617dee27438754cdfc9fe9bcf4cc024858

Add S-EL1 interrupt handling support in the TSPD ...

This patch adds support in the TSPD for registering a handler for
S-EL1 interrupts. This handler ferries the interrupts generated in the
non-secure state to the TSP at 'tsp_fiq_entry'. Support has been added
to the smc handler to resume execution in the non-secure state once
interrupt handling has been completed by the TSP.

There is also support for resuming execution in the normal world if
the TSP receives a EL3 interrupt. This code is currently unused.

Change-Id: I816732595a2635e299572965179f11aa0bf93b69

Use secure timer to generate S-EL1 interrupts ...

This patch adds support in the TSP to program the secure physical
generic timer to generate a EL-1 interrupt every half second. It also
adds support for maintaining the timer state across power management
operations. The TSPD ensures that S-EL1 can access the timer by
programming the SCR_EL3.ST bit.

This patch does not actually enable the timer. This will be done in a
subsequent patch once the complete framework for handling S-EL1
interrupts is in place.

Change-Id: I1b3985cfb50262f60824be3a51c6314ce90571bc

Introduce interrupt handling framework in BL3-1 ...

This patch adds a common handler for FIQ and IRQ exceptions in the
BL3-1 runtime exception vector table. This function determines the
interrupt type and calls its handler. A crash is reported if an
inconsistency in the interrupt management framework is detected. In
the event of a spurious interrupt, execution resumes from the
instruction where the interrupt was generated.

This patch also removes 'cm_macros.S' as its contents have been moved
to 'runtime_exceptions.S'

Change-Id: I3c85ecf8eaf43a3fac429b119ed0bd706d2e2093

Add context library API to change a bit in SCR_EL3 ...

This patch adds an API to write to any bit in the SCR_EL3 member of
the 'cpu_context' structure of the current CPU for a specified
security state. This API will be used in subsequent patches which
introduce interrupt management in EL3 to specify the interrupt routing
model when execution is not in EL3.

It also renames the cm_set_el3_elr() function to cm_set_elr_el3()
which is more in line with the system register name being targeted by
the API.

Change-Id: I310fa7d8f827ad3f350325eca2fb28cb350a85ed

Rework 'state' field usage in per-cpu TSP context ...

This patch lays the foundation for using the per-cpu 'state' field in
the 'tsp_context' structure for other flags apart from the power state
of the TSP.

It allocates 2 bits for the power state, introduces the necessary
macros to manipulate the power state in the 'state' field and
accordingly reworks all use of the TSP_STATE_* states.

It also allocates a flag bit to determine if the TSP is handling a
standard SMC. If this flag is set then the TSP was interrupted due to
non-secure or EL3 interupt depending upon the chosen routing
model. Macros to get, set and clear this flag have been added as
well. This flag will be used by subsequent patches.

Change-Id: Ic6ee80bd5895812c83b35189cf2c3be70a9024a6

Rework memory information passing to BL3-x images ...

The issues addressed in this patch are:

1. Remove meminfo_t from the common interfaces in BL3-x,
expecting that platform code will find a suitable mechanism
to determine the memory extents in these images and provide
it to the BL3-x images.

2. Remove meminfo_t and bl31_plat_params_t from all FVP BL3-x
code as the images use link-time information to determine
memory extents.

meminfo_t is still used by common interface in BL1/BL2 for
loading images

Change-Id: I4e825ebf6f515b59d84dc2bdddf6edbf15e2d60f

Populate BL31 input parameters as per new spec ...

This patch is based on spec published at
https://github.com/ARM-software/tf-issues/issues/133

It rearranges the bl31_args struct into
bl31_params and bl31_plat_params which provide the
information needed for Trusted firmware and platform
specific data via x0 and x1

On the FVP platform BL3-1 params and BL3-1 plat params
and its constituents are stored at the start of TZDRAM.

The information about memory availability and size for
BL3-1, BL3-2 and BL3-3 is moved into platform specific data.

Change-Id: I8b32057a3d0dd3968ea26c2541a0714177820da9

Introduce macros to manipulate the SPSR ...

This patch introduces macros (SPSR_64 and SPSR_32) to
create a SPSR for both aarch32 and aarch64 execution
states. These macros allow the user to set fields
in the SPSR depending upon its format.
The make_spsr() function which did not allow
manipulation of all the fields in the aarch32 SPSR
has been replaced by these new macros.

Change-Id: I9425dda0923e8d5f03d03ddb8fa0e28392c4c61e

Rework BL3-1 unhandled exception handling and reporting ...

This patch implements the register reporting when unhandled exceptions are
taken in BL3-1. Unhandled exceptions will result in a dump of registers
to the console, before halting execution by that CPU. The Crash Stack,
previously called the Exception Stack, is used for this activity.
This stack is used to preserve the CPU context and runtime stack
contents for debugging and analysis.

This also introduces the per_cpu_ptr_cache, referenced by tpidr_el3,
to provide easy access to some of BL3-1 per-cpu data structures.
Initially, this is used to provide a pointer to the Crash stack.

panic() now prints the the error file and line number in Debug mode
and prints the PC value in release mode.

The Exception Stack is renamed to Crash Stack with this patch.
The original intention of exception stack is no longer valid
since we intend to support several valid exceptions like IRQ
and FIQ in the trusted firmware context. This stack is now
utilized for dumping and reporting the system state when a
crash happens and hence the rename.

Fixes ARM-software/tf-issues#79 Improve reporting of unhandled exception

Change-Id: I260791dc05536b78547412d147193cdccae7811a

Fix broken standby state implementation in PSCI ...

This patch fixes the broken support for entry into standby states
introduced under commit-id 'd118f9f864' (tf-issues#94). Upon exit from
the platform defined standby state instead of returning to the caller
of the SMC, execution would get stuck in the wfi instruction meant for
entering a power down state. This patch ensures that exit from a
standby state and entry into a power down state do not interfere with
each other.

Fixes ARM-software/tf-issues#154

Change-Id: I56e5df353368e44d6eefc94ffedefe21929f5cfe

fvp: Provide per-EL MMU setup functions ...

Instead of having a single version of the MMU setup functions for all
bootloader images that can execute either in EL3 or in EL1, provide
separate functions for EL1 and EL3. Each bootloader image can then
call the appropriate version of these functions. The aim is to reduce
the amount of code compiled in each BL image by embedding only what's
needed (e.g. BL1 to embed only EL3 variants).

Change-Id: Ib86831d5450cf778ae78c9c1f7553fe91274c2fa

Merge pull request #63 from soby-mathew/sm/save_callee_saved_registers_in_cpu_context-1 ...

Preserve x19-x29 across world switch for exception handling

Preserve x19-x29 across world switch for exception handling ...

Previously exception handlers in BL3-1, X19-X29 were not saved
and restored on every SMC/trap into EL3. Instead these registers
were 'saved as needed' as a side effect of the A64 ABI used by the C
compiler.

That approach failed when world switching but was not visible
with the TSP/TSPD code because the TSP is 64-bit, did not
clobber these registers when running and did not support pre-emption
by normal world interrupts. These scenarios showed
that the values in these registers can be passed through a world
switch, which broke the normal and trusted world assumptions
about these registers being preserved.

The Ideal solution saves and restores these registers when a
world switch occurs - but that type of implementation is more complex.
So this patch always saves and restores these registers on entry and
exit of EL3.

Fixes ARM-software/tf-issues#141

Change-Id: I9a727167bbc594454e81cf78a97ca899dfb11c27

Access system registers directly in assembler ...

Instead of using the system register helper functions to read
or write system registers, assembler coded functions should
use MRS/MSR instructions. This results in faster and more
compact code.

This change replaces all usage of the helper functions with
direct register accesses.

Change-Id: I791d5f11f257010bb3e6a72c6c5ab8779f1982b3