This patch adds support for initialisation of PSCI CPUIdle states
from Low Power Idle(_LPI) entries in the ACPI tables when acpi is
enabled.
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently ARM CPUs DT bindings allows different enable-method value for
PSCI based systems. On ARM 64-bit this property is required and must be
"psci" while on ARM 32-bit systems this property is optional and must
be "arm,psci" if present.

However, "arm,psci" has always been the compatible string for the PSCI
node, and was never intended to be the enable-method. So this is a bug
in the binding and not a deliberate attempt at specifying 32-bit
differently.

This is problematic if 32-bit OS is run on 64-bit system which has
"psci" as enable-method rather than the expected "arm,psci".

So let's unify the value into "psci" and remove support for "arm,psci"
before it finds any users.
Reported-by: Soby Mathew <Soby.Mathew@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

The previous patch marked these two as 'static' which showed that they
are sometimes unused:

drivers/firmware/psci.c:103:13: error: 'psci_power_state_is_valid' defined but not used [-Werror=unused-function]
 static bool psci_power_state_is_valid(u32 state)
drivers/firmware/psci.c:94:13: error: 'psci_power_state_loses_context' defined but not used [-Werror=unused-function]
 static bool psci_power_state_loses_context(u32 state)

This also marks the functions 'inline', which has the main effect of
silently ignoring them when they are unused. The compiler will typically
inline small static functions anyway, so this seems more appropriate
than using __maybe_unused, which would have the same result otherwise.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 21e8868e ("drivers: firmware: psci: make two helper functions static")

psci_power_state_loses_context() and psci_power_state_is_valid are only
used internally now, so make them static.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

This is to fix below sparse warning:
drivers/firmware/psci.c:mmm:nn: warning: duplicate const
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

The psci_cpuidle_ops structures is not over-written, so add "const"
qualifier and replace __initdata with __initconst.
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

ARM64 PSCI kernel interfaces that initialize idle states and implement
the suspend API to enter them are generic and can be shared with the
ARM architecture.

To achieve that goal, this patch moves ARM64 PSCI idle management
code to drivers/firmware, so that the interface to initialize and
enter idle states can actually be shared by ARM and ARM64 arches
back-ends.

The ARM generic CPUidle implementation also requires the definition of
a cpuidle_ops section entry for the kernel to initialize the CPUidle
operations at boot based on the enable-method (ie ARM64 has the
statically initialized cpu_ops counterparts for that purpose); therefore
this patch also adds the required section entry on CONFIG_ARM for PSCI so
that the kernel can initialize the PSCI CPUidle back-end when PSCI is
the probed enable-method.

On ARM64 this patch provides no functional change.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arch/arm64]
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Switch to use a generic interface for issuing SMC/HVC based on ARM SMC
Calling Convention. Removes now the now unused psci-call.S.
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The PSCI specifications [1] and the SMC calling convention mandate
that unimplemented functions ids must return NOT_SUPPORTED (0xffffffff)
if a function id is called but it is not implemented.

Consequently, PSCI 1.0 function ids that require the 1.0 PSCI_FEATURES
call to be initialized:

CPU_SUSPEND (psci_init_cpu_suspend())
SYSTEM_SUSPEND (psci_init_system_suspend())

call the PSCI_FEATURES function id independently of the detected
PSCI firmware version, since, if the PSCI_FEATURES function id is not
implemented, it must return NOT_SUPPORTED according to the PSCI
specifications, causing the initialization functions to fail as expected.

Some existing PSCI implementations (ie Qemu PSCI emulation), do not
comply with the SMC calling convention and fail if function ids that are
not implemented are called from the OS, causing boot failures.

To solve this issue, this patch adds code that checks the PSCI firmware
version before calling PSCI 1.0 initialization functions so that the
OS makes sure that it is calling 1.0 functions only if the firmware
version detected is 1.0 or greater, therefore avoiding PSCI calls
that are bound to fail and might cause system boot failures owing
to non-compliant PSCI firmware implementations.

[1] http://infocenter.arm.com/help/topic/com.arm.doc.den0022c/DEN0022C_Power_State_Coordination_Interface.pdfSigned-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Tested-by: Kevin Hilman <khilman@kernel.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

PSCI v1.0 introduces a new API called PSCI_SYSTEM_SUSPEND. This API
provides the mechanism by which the calling OS can request entry into
the deepest possible system sleep state.

It meets all the necessary preconditions for entering suspend to RAM
state in Linux. This patch adds support for PSCI_SYSTEM_SUSPEND in psci
firmware and registers a psci system suspend operation to implement the
suspend-to-RAM(s2r) in a generic way on all the platforms implementing
PSCI.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This patch replaces the definition and usage of PSCI_0_2_FN_NATIVE with
the new and more generic macro PSCI_FN_NATIVE that can be used with any
version. This will be useful for the new features introduced in PSCIv1.0
and for any future revisions.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

PSCI 1.0 is designed to be fully compliant to the PSCI 0.2
specification, with minor differences that are described in the
PSCI specification.

In particular, PSCI v1.0 augments the specification with a new
power_state format (extended stateid - probeable through the
PSCI_FEATURES call), changes some function return codes and
functions usage requirements wrt PSCI 0.2. These changes mean
that 1.0 vs 0.2 compliancy should be enforced through a DT
compatible string that allows firmware to specify 1.0 only
compliancy so that older kernels are prevented from using
PSCI 1.0 FW implementations in a non-compatible way (eg by
calling a 1.0 FW implementation and expecting 0.2 behaviour).

This patch adds PSCI 1.0 DT bindings and related compatible
string.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>

PSCI v1.0 augmented the power_state parameter format specification
(extended stateid) and introduced a way to probe it through the
PSCI_FEATURES interface.

This patch implements code that detects the power_state format at
run-time through the PSCI_FEATURES interface, so that the power_state
argument can be properly detected and validated in the kernel according
to the information provided through firmware.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>

PSCI v1.0 introduces a PSCI_FEATURES call that allows to probe for
features related to a specific function identifier.

This patch adds PSCI_FEATURES support to the PSCI firmware layer.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>

Functions implemented on arm64 to check if a power_state parameter
is valid and if the power_state implies context loss are not
arm64 specific and should be moved to generic code so that they
can be reused on arm systems too.

This patch moves the functions handling the power_state parameter
to generic PSCI firmware layer code.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>

PSCI 1.0 introduces the INVALID_ADDRESS return value for functions
that take an address as input parameter (eg CPU_SUSPEND).

This patch adds INVALID_ADDRESS return value to kernel code and
updates the PSCI to linux error conversion to take it into account.

The kernel error value associated to INVALID_ADDRESS is set to
the error returned when the PSCI error code is INVALID_PARAMETERS
to comply with current call sites expected return value, given
that the kernel at present has no use for the additional error
information reported.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>

A 32-bit OS cannot make calls with SMC64 IDs, while a 64-bit OS must
invoke some PSCI functions with SMC64 IDs.

This patch introduces and makes use of a new macro to choose the
appropriate IDs based on the register width of the OS, which will allow
32-bit callers to use the PSCI client code.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

To enable sharing with arm, move the core PSCI framework code to
drivers/firmware. This results in a minor gain in lines of code, but
this will quickly be amortised by the removal of code currently
duplicated in arch/arm.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Nobody seems to be producing !SMP systems anymore, so this is just
becoming a source of kernel bugs, particularly if people want to use
coherent DMA with non-shared pages.

This patch forces CONFIG_SMP=y for arm64, removing a modest amount of
code in the process.
Signed-off-by: Will Deacon <will.deacon@arm.com>

This patch renames __cpu_suspend to cpu_suspend so that it's aligned
with ARM32. It also removes the redundant wrapper created.

This is in preparation to implement generic PSCI system suspend using
the cpu_{suspend,resume} which now has the same interface on both ARM
and ARM64.

Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

When building without CONFIG_HOTPLUG_CPU, GCC complains (rightly) that
psci_tos_resident_on is unused:

  arch/arm64/kernel/psci.c:61:13: warning: ‘psci_tos_resident_on’ defined but not used [-Wunused-function]
   static bool psci_tos_resident_on(int cpu)

As it's only ever used when CONFIG_HOTPLUG_CPU is selected, let's move
it into the existing ifdef.
Signed-off-by: Will Deacon <will.deacon@arm.com>
[Mark: write commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

The 32-bit ARM port doesn't have ACPI headers, and conditionally
including them is going to look horrendous. In preparation for sharing
the PSCI invocation code with 32-bit, move the acpi_psci_* function
declarations and definitions such that the PSCI client code need not
include ACPI headers.

While it would seem like we could simply hide the ACPI includes in
psci.h, the ACPI headers have hilarious circular dependencies which make
this infeasible without reorganising most of ACPICA. So rather than
doing that, move the acpi_psci_* prototypes into psci.h.

The psci_acpi_init function is made dependent on CONFIG_ACPI (with a
stub implementation in asm/psci.h) such that it need not be built for
32-bit ARM or kernels without ACPI support. The currently missing __init
annotations are added to the prototypes in the header.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Al Stone <al.stone@linaro.org>
Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>

A PSCI 1.0 implementation may choose to use the new extended StateID
format, the presence of which may be queried via the PSCI_FEATURES call.
The layout of this new StateID format is incompatible with the existing
format, and so to handle both we must abstract attempts to parse the
fields.

In preparation for PSCI 1.0 support, this patch introduces
psci_power_state_loses_context and psci_power_state_is_valid functions
to query information from a PSCI power state, which is no longer
decomposed (and hence the pack/unpack functions are removed). As it is
no longer decomposed, it is now passed round as an opaque u32 token.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>

Software resident in the secure world (a "Trusted OS") may cause CPU_OFF
calls for the CPU it is resident on to be denied. Such a denial would be
fatal for the kernel, and so we must detect when this can happen before
the point of no return.

This patch implements Trusted OS detection for PSCI 0.2+ systems, using
MIGRATE_INFO_TYPE and MIGRATE_INFO_UP_CPU. When a trusted OS is detected
as resident on a particular CPU, attempts to hot unplug that CPU will be
denied early, before they can prove fatal.

Trusted OS migration is not implemented by this patch. Implementation of
migratable UP trusted OSs seems unlikely, and the right policy for
migration is unclear (and will likely differ across implementations). As
such, it is likely that migration will require cooperation with Trusted
OS drivers.

PSCI implementations prior to 0.1 do not provide the facility to detect
the presence of a Trusted OS, nor the CPU any such OS is resident on, so
without additional information it is not possible to handle Trusted OSs
with PSCI 0.1.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>

PSCI_VERSION and MIGRATE_INFO_TYPE_UP_CPU return unsigned values, with
the latter returning a 64-bit value. However, the PSCI invocation
functions have prototypes returning int.

This patch upgrades the invocation functions to return unsigned long,
with a new typedef to keep things legible. As PSCI_VERSION cannot return
a negative value, the erroneous check against PSCI_RET_NOT_SUPPORTED is
also removed. The unrelated psci_initcall_t typedef is moved closer to
its first user, to avoid confusion with the invocation functions.

In preparation for sharing the code with ARM, unsigned long is used in
preference of u64. In the SMC32 calling convention, the relevant fields
will be 32 bits wide.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>

PSCI 0.1 did not define canonical IDs for CPU_ON, CPU_OFF, CPU_SUSPEND,
or MIGRATE, and so these need to be provided when using firmware
compliant to PSCI 0.1.

However, functions introduced in 0.2 or later have canonical IDs, and
these cannot be provided via DT. There's no need to indirect the IDs via
a table; they can be used directly at callsites (and already are for
SYSTEM_OFF and SYSTEM_RESET).

This patch removes the unnecessary function ID indirection for
AFFINITY_INFO and MIGRATE_INFO_TYPE.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>

cpu_kill currently returns one for success and zero for failure, which
is unlike all the other cpu_operations, which return zero for success
and an error code upon failure. This difference is unnecessarily
confusing.

Make cpu_kill consistent with the other cpu_operations.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>

ARM64 CPU operations such as cpu_init and cpu_init_idle take
a struct device_node pointer as a parameter, which corresponds to
the device tree node of the logical cpu on which the operation
has to be applied.

With the advent of ACPI on arm64, where MADT static table entries
are used to initialize cpus, the device tree node parameter
in cpu_ops hooks become useless when booting with ACPI, since
in that case cpu device tree nodes are not present and can not be
used for cpu initialization.

The current cpu_init hook requires a struct device_node pointer
parameter because it is called while parsing the device tree to
initialize CPUs, when the cpu_logical_map (that is used to match
a cpu node reg property to a device tree node) for a given logical
cpu id is not set up yet. This means that the cpu_init hook cannot
rely on the of_get_cpu_node function to retrieve the device tree
node corresponding to the logical cpu id passed in as parameter,
so the cpu device tree node must be passed in as a parameter to fix
this catch-22 dependency cycle.

This patch reshuffles the cpu_logical_map initialization code so
that the cpu_init cpu_ops hook can safely use the of_get_cpu_node
function to retrieve the cpu device tree node, removing the need for
the device tree node pointer parameter.

In the process, the patch removes device tree node parameters
from all cpu_ops hooks, in preparation for SMP DT/ACPI cpus
initialization consolidation.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com> [DT]
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

PSCI v0.2+ allows the kernel to probe the PSCI firmware version.

This patch replaces the default initialization of PSCI v0.2+
functions with code that allows probing PSCI firmware version
and initializes PSCI functions accordingly.

Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

PSCI v0.2+ versions provide a specific PSCI call (PSCI_VERSION) to
detect the PSCI version at run-time. Current PSCI v0.2 init code
carries out the version probing in the PSCI 0.2 DT init function,
but the version probing does not depend on DT so it can be factored out
in order to make it available to other boot mechanisms (ie ACPI) to
reuse. The psci_probe() probing function can be easily extended
to add detection and initialization of PSCI functions defined in
PSCI versions >0.2.

Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

There are two flags: PSCI_COMPLIANT and PSCI_USE_HVC. When set,
the former signals to the OS that the firmware is PSCI compliant.
The latter selects the appropriate conduit for PSCI calls by
toggling between Hypervisor Calls (HVC) and Secure Monitor Calls
(SMC).

FADT table contains such information in ACPI 5.1, FADT table was
parsed in ACPI table init and copy to struct acpi_gbl_FADT, so
use the flags in struct acpi_gbl_FADT for PSCI init.

Since ACPI 5.1 doesn't support self defined PSCI function IDs,
which means that only PSCI 0.2+ is supported in ACPI.

CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Yijing Wang <wangyijing@huawei.com>
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
Tested-by: Timur Tabi <timur@codeaurora.org>
Tested-by: Robert Richter <rrichter@cavium.com>
Acked-by: Robert Richter <rrichter@cavium.com>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

An arm64 allmodconfig fails to build with GCC 5 due to __asmeq
assertions in the PSCI firmware calling code firing due to mcount
preambles breaking our assumptions about register allocation of function
arguments:

  /tmp/ccDqJsJ6.s: Assembler messages:
  /tmp/ccDqJsJ6.s:60: Error: .err encountered
  /tmp/ccDqJsJ6.s:61: Error: .err encountered
  /tmp/ccDqJsJ6.s:62: Error: .err encountered
  /tmp/ccDqJsJ6.s:99: Error: .err encountered
  /tmp/ccDqJsJ6.s:100: Error: .err encountered
  /tmp/ccDqJsJ6.s:101: Error: .err encountered

This patch fixes the issue by moving the PSCI calls out-of-line into
their own assembly files, which are safe from the compiler's meddling
fingers.
Reported-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

ARM64_CPU_SUSPEND config option was introduced to make code providing
context save/restore selectable only on platforms requiring power
management capabilities.

Currently ARM64_CPU_SUSPEND depends on the PM_SLEEP config option which
in turn is set by the SUSPEND config option.

The introduction of CPU_IDLE for arm64 requires that code configured
by ARM64_CPU_SUSPEND (context save/restore) should be compiled in
in order to enable the CPU idle driver to rely on CPU operations
carrying out context save/restore.

The ARM64_CPUIDLE config option (ARM64 generic idle driver) is therefore
forced to select ARM64_CPU_SUSPEND, even if there may be (ie PM_SLEEP)
failed dependencies, which is not a clean way of handling the kernel
configuration option.

For these reasons, this patch removes the ARM64_CPU_SUSPEND config option
and makes the context save/restore dependent on CPU_PM, which is selected
whenever either SUSPEND or CPU_IDLE are configured, cleaning up dependencies
in the process.

This way, code previously configured through ARM64_CPU_SUSPEND is
compiled in whenever a power management subsystem requires it to be
present in the kernel (SUSPEND || CPU_IDLE), which is the behaviour
expected on ARM64 kernels.

The cpu_suspend and cpu_init_idle CPU operations are added only if
CPU_IDLE is selected, since they are CPU_IDLE specific methods and
should be grouped and defined accordingly.

PSCI CPU operations are updated to reflect the introduced changes.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Fix build failure of defconfig when PM_SLEEP is disabled (e.g. by
disabling SUSPEND) and CPU_IDLE enabled:

arch/arm64/kernel/psci.c:543:2: error: unknown field ‘cpu_suspend’ specified in initializer
  .cpu_suspend = cpu_psci_cpu_suspend,
  ^
arch/arm64/kernel/psci.c:543:2: warning: initialization from incompatible pointer type [enabled by default]
arch/arm64/kernel/psci.c:543:2: warning: (near initialization for ‘cpu_psci_ops.cpu_prepare’) [enabled by default]
make[1]: *** [arch/arm64/kernel/psci.o] Error 1

The cpu_operations.cpu_suspend field exists only if ARM64_CPU_SUSPEND is
defined, not CPU_IDLE.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

This fix rectifies the psci cpu_suspend implementation to check the
PSCI power state parameter type field associated with the requested idle
state index.
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

During the 3.18 merge period additional __get_cpu_var uses were
added. The patch converts these to this_cpu_ptr().
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

This patch implements the cpu_suspend cpu operations method through
the PSCI CPU SUSPEND API. The PSCI implementation translates the idle state
index passed by the cpu_suspend core call into a valid PSCI state according to
the PSCI states initialized at boot through the cpu_init_idle() CPU
operations hook.

The PSCI CPU suspend operation hook checks if the PSCI state is a
standby state. If it is, it calls the PSCI suspend implementation
straight away, without saving any context. If the state is a power
down state the kernel calls the __cpu_suspend API (that saves the CPU
context) and passed the PSCI suspend finisher as a parameter so that PSCI
can be called by the __cpu_suspend implementation after saving and flushing
the context as last function before power down.

For power down states, entry point is set to cpu_resume physical address,
that represents the default kernel execution address following a CPU reset.
Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

PSCI init functions must be marked as __init so that they are freed
by the kernel upon boot.

This patch marks the PSCI init functions as such since they need not
be persistent in the kernel address space after the kernel has booted.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

PSCI CPU operations have to be enabled on UP kernels so that calls
like eg cpu_suspend can be made functional on UP too.

This patch reworks the PSCI CPU operations so that they can be
enabled on UP systems.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

PSCIv0.2 adds a new function called AFFINITY_INFO, which
can be used to query if a specified CPU has actually gone
offline. Calling this function via cpu_kill ensures that
a CPU has quiesced after a call to cpu_die. This helps
prevent the CPU from doing arbitrary bad things when data
or instructions are clobbered (as happens with kexec)
in the window between a CPU announcing that it is dead
and said CPU leaving the kernel.
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>