The multi-cluster SMP code maps the address spaces of several hardware
control blocks. The device nodes for them are SoC-specific. To help with
supporting other SoCs to re-use this code, these bits should be split
out to a separate function tied to the enable-method string.
This patch splits out and groups the device node lookup sequence, and
adds new data structures to have the newly created function tied to
the enable method string. This structure can also be used to encode
other differences between the SoCs.
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Instead of having an early init function check the machine compatible
and installing multi-cluster SMP support for the A80 if it matches,
use a new cpu enable-method string. This makes the platform support
future proof in case anyone manages to add PSCI support.
The original init code for the SMP support is changed into the
.prepare_cpus callback in the smp_operations structure. Instead of
panicing when resources are missing like on some platforms, our code
merely guards against engaging SMP or CPU hotplug and returns an error.
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
The sunxi_mc_smp_lookback function is modeled after the mcpm_loopback
function in the MCPM framework. "lookback" was a typo introduced when
the new function was added.
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
The BROM has a branch that checks if the primary core is hotplugging.
If the magic flag is set, execution jumps to the address set in the
software entry register. (Secondary cores always branch to the that
address.)
This patch sets the flags that makes BROM jump execution on the
primary core (cpu0) to the SMP software entry code when the core is
powered back up. After it is re-integrated into the system, the flag
is cleared.
A custom .cpu_can_disable callback that returns true for all cpus,
so that cpu0 can really be brought down.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
This patch adds common code used to power down all cores and clusters.
The code was previously based on the MCPM framework. It has now been
adapted to hook into struct smp_operations directly, but the code
structure still shows signs of prior work.
The primary core (cpu0) requires setting flags to have the BROM bounce
execution to the SMP software entry code. This is done in a subsequent
patch to keep the changes cleanly separated. By default the ARM SMP code
blocks cpu0 from being turned off, so splitting this out is safe.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
The A80 is a big.LITTLE SoC with 1 cluster of 4 Cortex-A7s and
1 cluster of 4 Cortex-A15s.
This patch adds support to bring up the second cluster and thus all
cores using custom platform SMP code. Core/cluster power down has not
been implemented, thus CPU hotplugging is not supported.
Parts of the trampoline and re-entry code for the boot cpu was adapted
from the MCPM framework.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Chen-Yu Tsai