Some additional register writes are required when hotplugging CPUs
on gs101, without these the system hangs when hotplugging.
Specifically a CPU_INFORM register needs to be programmed with
a hint value which is used by the EL3 firmware (el3mon) and the
pmu-intr-gen registers need to be programmed.
With this patch applied, and corresponding DT update CPU hotplug
now works as expected. e.g.
echo 0 > /sys/devices/system/cpu/cpu6/online
echo 1 > /sys/devices/system/cpu/cpu6/online
Note: to maintain compatibility with older DTs that didn't specify
pmu-intr-gen phandle only a warning is issued if the syscon can't
be obtained.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://lore.kernel.org/r/20250506-contrib-pg-cpu-hotplug-suspend2ram-fixes-v1-v4-5-9f64a2657316@linaro.org
[krzk: few blank line and white-space alignment fixes from checkpatch]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Some Exynos based SoCs like Tensor gs101 protect the PMU registers for
security hardening reasons so that they are only write accessible in el3
via an SMC call.
As most Exynos drivers that need to write PMU registers currently obtain a
regmap via syscon (phys, pinctrl, watchdog). Support for the above usecase
is implemented in this driver using a custom regmap similar to syscon to
handle the SMC call. Platforms that don't secure PMU registers, get a mmio
regmap like before. As regmaps abstract out the underlying register access
changes to the leaf drivers are minimal.
A new API exynos_get_pmu_regmap_by_phandle() is provided for leaf drivers
that currently use syscon_regmap_lookup_by_phandle(). This also handles
deferred probing.
Tested-by: Sam Protsenko <semen.protsenko@linaro.org>
Tested-by: Alexey Klimov <alexey.klimov@linaro.org>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://lore.kernel.org/r/20240220220613.797068-2-peter.griffin@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Support for the Exynos4212 SoC was originally dropped as there were
no boards using it. We will be adding a device that uses it, so add
it back.
This reverts commit c40610198f.
Signed-off-by: Artur Weber <aweber.kernel@gmail.com>
Link: https://lore.kernel.org/r/20230501195525.6268-5-aweber.kernel@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Fix up inconsistent usage of upper and lowercase letters in "Samsung"
and "Exynos" names.
"SAMSUNG" and "EXYNOS" are not abbreviations but regular trademarked
names. Therefore they should be written with lowercase letters starting
with capital letter.
The lowercase "Exynos" name is promoted by its manufacturer Samsung
Electronics Co., Ltd., in advertisement materials and on website.
Although advertisement materials usually use uppercase "SAMSUNG", the
lowercase version is used in all legal aspects (e.g. on Wikipedia and in
privacy/legal statements on
https://www.samsung.com/semiconductor/privacy-global/).
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Support for Exynos4212 SoCs has been removed by commit bca9085e0a ("ARM:
dts: exynos: remove Exynos4212 support (dead code)"), so there is no need
to keep remaining dead code related to this SoC version.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The Exynos Power Management Unit (PMU) drivers contain quite large
static arrays of register values necessary for given Exynos SoC to enter
low power mode. All this data is useless for ARMv8 SoC like
Exynos5433, because the image will not be shared between ARMv7 and
ARMv8.
Add additional Kconfig symbol for selecting the SoC-specific driver
addons thus skipping the useless data in the final image (this is
similar approach to chosen for Exynos clock controller drivers):
- exynos-pmu driver will be compiled on both architectures ARMv7
and ARMv8,
- additional driver_data for ARMv7 SoCs will not be built on ARMv8
and a macro will return NULL for them in of_device_id - this should
be safe as these compatibles cannot match on ARMv7 and driver
anyway handles NULL driver_data,
- on ARMv8 compile only exynos-pmu driver which exposes the
syscon-regmap for PMU address space.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
This patch moves Exynos PMU driver implementation from "arm/mach-exynos"
to "drivers/soc/samsung". This driver is mainly used for setting misc
bits of register from PMU IP of Exynos SoC which will be required to
configure before Suspend/Resume. Currently all these settings are done
in "arch/arm/mach-exynos/pmu.c" but moving ahead for ARM64 based SoC
support, there is a need of this PMU driver in driver/* folder.
This driver uses existing DT binding information and there should
be no functionality change in the supported platforms.
Signed-off-by: Amit Daniel Kachhap <amitdanielk@gmail.com>
[tested on Peach-Pi (Exynos5880)]
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
[for testing on Trats2 (Exynos4412) and Odroid XU3 (Exynos5422)]
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
[k.kozlowski: Rebased, add necessary infrastructure for building and
selecting drivers/soc because original patchset was on top of movement
SROMc to drivers/soc]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
