Both psci_system_reset and psci_system_off call psci_ops->system_reset,
which seems like a copy-paste error as there is an unused ->system_off
as well.

Adjust psci_system_off to use ->system_off instead. This won't matter
for the existing i.MX7 PSCI implementation because it defines neither
callback, but it will for the upcoming STM32MP PSCI support.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

of_psci_fixup() can be used by code which doesn't use the barebox
psci implementation, but provides its own PSCI compatible firmware.
Factor it out to a separate file to compile it independently of the
barebox PSCI implementation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Since 2c20674f0c ("ARM: Add code to support SMCCC on AArch64") we have
both arch/arm/include/asm/arm-smccc.h and include/linux/arm-smccc.h.
The latter was introduced with Kernel commit 680a0873e ("arm: kernel:
Add SMC structure parameter") included, so we have to add the parameter
for ARM32 aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Avoid missing prototypes warning by adding prototypes. Since these
functions are called from assembly add the prototypes to the C file
directly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Remove what looks like a leftover code that doesn't appear to be
referenced anywhere.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Explicitly add psci command to the misc group to get rid of
the warning that the command has no group.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Replace users which use of_set_property() to set a property to a string
with of_property_write_string().

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This adds the SoC specific PSCI bits for i.MX7. Based on the
corresponding U-Boot code.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This patch contains the barebox implementation for the ARM
"Power State Coordination Interface" (PSCI).

The interface is aimed at the generalization of code in the following
power management scenarios:
* Core idle management.
* Dynamic addition and removal of cores, and secondary core boot.
* big.LITTLE migration.
* System shutdown and reset.

In practice, all that's currently implemented is a way to enable the
secondary core one some SoCs.

With PSCI the Kernel is either started in nonsecure or in Hypervisor
mode and PSCI is used to apply power to the secondary cores.

The start mode is passed in the global.bootm.secure_state variable. This
enum can contain "secure" (Kernel is started in secure mode, means no
PSCI), "nonsecure" (Kernel is started in nonsecure mode, PSCI available)
or "hyp" (Kernel is started in hyp mode, meaning it can support
virtualization).

We currently only support putting the secure monitor code into SDRAM,
which means we always steal some amount of memory from the Kernel.
To keep things simple for now we simply keep the whole barebox binary in
memory

The PSCI support has been tested on i.MX7 only so far. The only
supported operations are CPU_ON and CPU_OFF.

The PSCI and secure monitor code is based on the corresponding U-Boot
code.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>