If an SCP firmware is present and able to communicate via SCPI, then use
that to implement CPU and system power state transitions, including CPU
hotplug and system suspend. Otherwise, fall back to the existing CPU
power control implementation.

The last 16 KiB of SRAM A2 are reserved for the SCP firmware, and the
SCPI shared memory is at the very end of this region (and therefore the
end of SRAM A2). BL31 continues to start at the beginning of SRAM A2
(not counting the ARISC exception vector area) and fills up to the
beginning of the SCP firmware.

Because the SCP firmware is not loaded adjacent to the ARISC exception
vector area, the jump instructions used for exception handling cannot be
included in the SCP firmware image, and must be initialized here before
turning on the SCP.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: I37b9b9636f94d4125230423726f3ac5e9cdb551c

The action of last resort isn't going to change between SoCs. This moves
that code back to the PSCI implementation, where it more obviously
matches the code in sunxi_system_reset().

The two error messages say essentially the same thing anyway.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: I62ac35fdb5ed78a016e9b18281416f1dcea38a4a

Some Allwinner H6 has a broken watchdog that doesn't
make the soc reboot.

Use the R_WATCHDOG instead.

Signed-off-by: Clément Péron <peron.clem@gmail.com>
Change-Id: Ie95cc30a80ed517b60b30d6bc2e655a1b53f18ba

Convert them to take an mpidr instead of a (cluster, core) pair. This
simplifies all of the call sites, and actually makes the functions a bit
smaller.

Signed-off-by: Samuel Holland <samuel@sholland.org>

Enforce full include path for includes. Deprecate old paths.

The following folders inside include/lib have been left unchanged:

- include/lib/cpus/${ARCH}
- include/lib/el3_runtime/${ARCH}

The reason for this change is that having a global namespace for
includes isn't a good idea. It defeats one of the advantages of having
folders and it introduces problems that are sometimes subtle (because
you may not know the header you are actually including if there are two
of them).

For example, this patch had to be created because two headers were
called the same way: e0ea0928d5b7 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a282 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca33988b9 ("Move include and
source files to logical locations"). At that time, there weren't too
many headers so it wasn't a real issue. However, time has shown that
this creates problems.

Platforms that want to preserve the way they include headers may add the
removed paths to PLAT_INCLUDES, but this is discouraged.

Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

PSCI requires a core to turn itself off, which we can't do properly by
just executing an algorithm on that very core. As a consequence we just
put a core into WFI on CPU_OFF right now.
To fix this let's task the "arisc" management processor (an OpenRISC
core) with that task of asserting reset and turning off the core's power
domain. We use a handcrafted sequence of OpenRISC instructions to
achieve this, and hand this data over to the new sunxi_execute_arisc_code()
routine.
The commented source code for this routine is provided in a separate file,
but the ATF code contains the already encoded instructions as data.
The H6 uses the same algorithm, but differs in the MMIO addresses, so
provide a SoC (family) specific copy of that code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>

So far we have a sunxi_private.h header file in the common code directory.
This holds the prototypes of various functions we share in *common*
code. However we will need some of those in the platform specific code
parts as well, and want to introduce new functions shared across the
whole platform port.

So move the sunxi_private.h file into the common/include directory, so
that it becomes visible to all parts of the platform code.
Fix up the existing #includes and add missing ones, also add the
sunxi_read_soc_id() prototype here.

This will be used in follow up patches.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>

The AXP805 PMIC used with H6 is capable of shutting down the system.

Add support for using it to shut down the system power.

The original placeholder power off code is moved to A64 code, as it's
still TODO to implement PMIC operations for A64.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>

The DRAM controller supports up to 4GB of DRAM, and there are actually
boards out there where we can use at least 3GB of this.

Relax the PSCI entry point check, to be not restricted to 2GB of DRAM.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>

The reset vector entry point is preserved across CPU resets, so it only
needs to be set once at boot.

Hotplugged CPUs are not actually powered down, but are put in a wfi with
the GIC disconnected.

With this commit, Linux is able to enable, hotplug and use all four CPUs.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

sun50i_cpu_on will be used by the PSCI implementation to initialize
secondary cores for SMP. Unfortunately, sun50i_cpu_off is not usable by
PSCI directly, because it is not possible for a CPU to use this function
to power itself down. Power cannot be shut off until the outputs are
clamped, and MMIO does not work once the outputs are clamped.

But at least CPU0 can shutdown the other cores early in the BL31 boot
process and before shutting down the system.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

This platform supports Allwinner's SoCs with ARMv8 cores. So far they
all sport a single cluster of Cortex-A53 cores.

"sunxi" is the original code name used for this platform, and since it
appears in the Linux kernel and in U-Boot as well, we use it here as a
short file name prefix and for identifiers.

This port includes BL31 support only. U-Boot's SPL takes the role of the
primary loader, also doing the DRAM initialization. It then loads the
rest of the firmware, namely ATF and U-Boot (BL33), then hands execution
over to ATF.

This commit includes the basic platform code shared across all SoCs.
There is no platform.mk yet.

[Andre: moved files into proper directories, supported RESET_TO_BL31,
	various clean ups and simplifications ]

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>