This patch adds support to save the "power state" parameter before the
affinity level specific handlers are called in a CPU_SUSPEND call.
This avoids the need to pass the power_state as a parameter to the
handlers and Secure Payload Dispatcher (SPD) suspend spd_pm_ops.
The power_state arguments in the spd_pm_ops operations are now reserved
and must not be used. The SPD can query the relevant power_state fields
by using the psci_get_suspend_afflvl() & psci_get_suspend_stateid() APIs.

NOTE: THIS PATCH WILL BREAK THE SPD_PM_OPS INTERFACE. HENCE THE SECURE
PAYLOAD DISPATCHERS WILL NEED TO BE REWORKED TO USE THE NEW INTERFACE.

Change-Id: I1293d7dc8cf29cfa6a086a009eee41bcbf2f238e

This patch replaces the internal psci_save_ns_entry() API with a
psci_get_ns_ep_info() API. The new function splits the work done by the
previous one such that it populates and returns an 'entry_point_info_t'
structure with the information to enter the normal world upon completion
of the CPU_SUSPEND or CPU_ON call. This information is used to populate
the non-secure context structure separately.

This allows the new internal API `psci_get_ns_ep_info` to return error
and enable the code to return safely.

Change-Id: Ifd87430a4a3168eac0ebac712f59c93cbad1b231

This patch moves the bakery locks out of coherent memory to normal memory.
This implies that the lock information needs to be placed on a separate cache
line for each cpu. Hence the bakery_lock_info_t structure is allocated in the
per-cpu data so as to minimize memory wastage. A similar platform per-cpu
data is introduced for the platform locks.

As a result of the above changes, the bakery lock api is completely changed.
Earlier, a reference to the lock structure was passed to the lock implementation.
Now a unique-id (essentially an index into the per-cpu data array) and an offset
into the per-cpu data for bakery_info_t needs to be passed to the lock
implementation.

Change-Id: I1e76216277448713c6c98b4c2de4fb54198b39e0

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

This patch implements the following cleanups in PSCI generic code:

1. It reworks the affinity level specific handlers in the PSCI implementation
   such that.

   a. Usage of the 'rc' local variable is restricted to only where it is
      absolutely needed

   b. 'plat_state' local variable is defined only when a direct invocation of
      plat_get_phys_state() does not suffice.

   c. If a platform handler is not registered then the level specific handler
      returns early.

2. It limits the use of the mpidr_aff_map_nodes_t typedef to declaration of
   arrays of the type instead of using it in function prototypes as well.

3. It removes dangling declarations of __psci_cpu_off() and
   __psci_cpu_suspend(). The definitions of these functions were removed in
   earlier patches.

Change-Id: I51e851967c148be9c2eeda3a3c41878f7b4d6978

This patch adds APIs to find, save and retrieve the highest affinity level which
will enter or exit from the physical OFF state during a PSCI power management
operation. The level is stored in per-cpu data.

It then reworks the PSCI implementation to perform cache maintenance only
when the handler for the highest affinity level to enter/exit the OFF state is
called.

For example. during a CPU_SUSPEND operation, state management is done prior to
calling the affinity level specific handlers. The highest affinity level which
will be turned off is determined using the psci_find_max_phys_off_afflvl()
API. This level is saved using the psci_set_max_phys_off_afflvl() API. In the
code that does generic handling for each level, prior to performing cache
maintenance it is first determined if the current affinity level matches the
value returned by psci_get_max_phys_off_afflvl(). Cache maintenance is done if
the values match.

This change allows the last CPU in a cluster to perform cache maintenance
independently. Earlier, cache maintenance was started in the level 0 handler and
finished in the level 1 handler. This change in approach will facilitate
implementation of tf-issues#98.

Change-Id: I57233f0a27b3ddd6ddca6deb6a88b234525b0ae6

This patch pulls out state management from the affinity level specific handlers
into the top level functions specific to the operation
i.e. psci_afflvl_suspend(), psci_afflvl_on() etc.

In the power down path this patch will allow an affinity instance at level X to
determine the state that an affinity instance at level X+1 will enter before the
level specific handlers are called. This will be useful to determine whether a
CPU is the last in the cluster during a suspend/off request and so on.

Similarly, in the power up path this patch will allow an affinity instance at
level X to determine the state that an affinity instance at level X+1 has
emerged from, even after the level specific handlers have been called. This will
be useful in determining whether a CPU is the first in the cluster during a
on/resume request and so on.

As before, while powering down, state is updated before the level specific
handlers are invoked so that they can perform actions based upon their target
state. While powering up, state is updated after the level specific handlers have
been invoked so that they can perform actions based upon the state they emerged
from.

Change-Id: I40fe64cb61bb096c66f88f6d493a1931243cfd37

This patch adds a structure defined by the PSCI service to the per-CPU data
array. The structure is used to save the 'power_state' parameter specified
during a 'cpu_suspend' call on the current CPU. This parameter was being saved
in the cpu node in the PSCI topology tree earlier.

The existing API to return the state id specified during a PSCI CPU_SUSPEND call
i.e. psci_get_suspend_stateid(mpidr) has been renamed to
psci_get_suspend_stateid_by_mpidr(mpidr). The new psci_get_suspend_stateid() API
returns the state id of the current cpu.

The psci_get_suspend_afflvl() API has been changed to return the target affinity
level of the current CPU. This was specified using the 'mpidr' parameter in the
old implementation.

The behaviour of the get_power_on_target_afflvl() has been tweaked such that
traversal of the PSCI topology tree to locate the affinity instance node for the
current CPU is done only in the debug build as it is an expensive operation.

Change-Id: Iaad49db75abda471f6a82d697ee6e0df554c4caf

This patch adds support for SYSTEM_OFF and SYSTEM_RESET PSCI
operations. A platform should export handlers to complete the
requested operation. The FVP port exports fvp_system_off() and
fvp_system_reset() as an example.

If the SPD provides a power management hook for system off and
system reset, then the SPD is notified about the corresponding
operation so it can do some bookkeeping. The TSPD exports
tspd_system_off() and tspd_system_reset() for that purpose.

Versatile Express shutdown and reset methods have been removed
from the FDT as new PSCI sys_poweroff and sys_reset services
have been added. For those kernels that do not support yet these
PSCI services (i.e. GICv3 kernel), the original dtsi files have
been renamed to *-no_psci.dtsi.

Fixes ARM-software/tf-issues#218

Change-Id: Ic8a3bf801db979099ab7029162af041c4e8330c8

This patch uses stacks allocated in normal memory to enable the MMU early in the
warm boot path thus removing the dependency on stacks allocated in coherent
memory. Necessary cache and stack maintenance is performed when a cpu is being
powered down and up. This avoids any coherency issues that can arise from
reading speculatively fetched stale stack memory from another CPUs cache. These
changes affect the warm boot path in both BL3-1 and BL3-2.

The EL3 system registers responsible for preserving the MMU state are not saved
and restored any longer. Static values are used to program these system
registers when a cpu is powered on or resumed from suspend.

Change-Id: I8357e2eb5eb6c5f448492c5094b82b8927603784

Many of the interfaces internal to PSCI pass the current CPU
MPIDR_EL1 value from function to function. This is not required,
and with inline access to the system registers is less efficient
than requiring the code to read that register whenever required.

This patch remove the mpidr parameter from the affected interfaces
and reduces code in FVP BL3-1 size by 160 bytes.

Change-Id: I16120a7c6944de37232016d7e109976540775602

The array of affinity nodes is currently allocated for 32 entries
with the PSCI_NUM_AFFS value defined in psci.h. This is not enough
for large systems, and will substantially over allocate the array
for small systems.

This patch introduces an optional platform definition
PLATFORM_NUM_AFFS to platform_def.h. If defined this value is
used for PSCI_NUM_AFFS, otherwise a value of two times the number
of CPU cores is used.

The FVP port defines PLATFORM_NUM_AFFS to be 10 which saves
nearly 1.5KB of memory.

Fixes ARM-software/tf-issues#192

Change-Id: I68e30ac950de88cfbd02982ba882a18fb69c1445

psci_suspend_context is an array of cache-line aligned structures
containing the single power_state integer per cpu. This array is
the only structure indexed by the aff_map_node.data integer.

This patch saves 2KB of BL3-1 memory by placing the CPU
power_state value directly in the aff_map_node structure. As a
result, this value is now never cached and the cache clean when
writing the value is no longer required.

Fixes ARM-software/tf-issues#195

Change-Id: Ib4c70c8f79eed295ea541e7827977a588a19ef9b

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

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

Change-Id: I038632af3c32d88984cd25b886c43ff763269bf9

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

Change-Id: Ia0549786796d8bf5956487e8996450a0b3d79f32

Update code base to remove variables from the .data section,
mainly by using const static data where possible and adding
the const specifier as required. Most changes are to the IO
subsystem, including the framework APIs. The FVP power
management code is also affected.

Delay initialization of the global static variable,
next_image_type in bl31_main.c, until it is realy needed.
Doing this moves the variable from the .data to the .bss
section.

Also review the IO interface for inconsistencies, using
uintptr_t where possible instead of void *. Remove the
io_handle and io_dev_handle typedefs, which were
unnecessary, replacing instances with uintptr_t.

Fixes ARM-software/tf-issues#107.

Change-Id: I085a62197c82410b566e4698e5590063563ed304

Reduce the number of header files included from other header
files as much as possible without splitting the files. Use forward
declarations where possible. This allows removal of some unnecessary
"#ifndef __ASSEMBLY__" statements.

Also, review the .c and .S files for which header files really need
including and reorder the #include statements alphabetically.

Fixes ARM-software/tf-issues#31

Change-Id: Iec92fb976334c77453e010b60bcf56f3be72bd3e

Add tag names to all unnamed structs in header files. This
allows forward declaration of structs, which is necessary to
reduce header file nesting (to be implemented in a subsequent
commit).

Also change the typedef names across the codebase to use the _t
suffix to be more conformant with the Linux coding style. The
coding style actually prefers us not to use typedefs at all but
this is considered a step too far for Trusted Firmware.

Also change the IO framework structs defintions to use typedef'd
structs to be consistent with the rest of the codebase.

Change-Id: I722b2c86fc0d92e4da3b15e5cab20373dd26786f

Move the PSCI global functions out of psci_private.h and into
psci.h to allow the standard service to only depend on psci.h.

Change-Id: I8306924a3814b46e70c1dcc12524c7aefe06eed1

This patch saves the 'power_state' parameter prior to suspending
a cpu and invalidates it upon its resumption. The 'affinity level'
and 'state id' fields of this parameter can be read using a set of
public and private apis. Validation of power state parameter is
introduced which checks for SBZ bits are zero.
This change also takes care of flushing the parameter from the cache
to main memory. This ensures that it is available after cpu reset
when the caches and mmu are turned off. The earlier support for
saving only the 'affinity level' field of the 'power_state' parameter
has also been reworked.

Fixes ARM-Software/tf-issues#26
Fixes ARM-Software/tf-issues#130

Change-Id: Ic007ccb5e39bf01e0b67390565d3b4be33f5960a

This patch implements ARM Standard Service as a runtime service and adds
support for call count, UID and revision information SMCs. The existing
PSCI implementation is subsumed by the Standard Service calls and all
PSCI calls are therefore dispatched by the Standard Service to the PSCI
handler.

At present, PSCI is the only specification under Standard Service. Thus
call count returns the number of PSCI calls implemented. As this is the
initial implementation, a revision number of 0.1 is returned for call
revision.

Fixes ARM-software/tf-issues#62

Change-Id: I6d4273f72ad6502636efa0f872e288b191a64bc1