On Polarfire SoC, the Bank 2 and Bank 4 IOs connected to the
Multiprocessor Subsystem (MSS) are controlled by IOMUX_CRs 1 through 6,
which determine what function in routed to them, and
MSSIO_BANK#_IO_CFG_CRs, which determine the configuration of each pin.
Document it, including several custom configuration options that stem
from MSS Configurator options (the MSS Configurator is part of the FPGA
tooling for this device). "ibufmd" unfortunately is not a 1:1 mapping
with an MSS Configurator option, unlike clamp-diode or lockdown, and I
do not know the effect of any bits in the field. I have no been able to
find an explanation for these bits in documentation.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Linus Walleij <linusw@kernel.org>
On Polarfire SoC, iomux0 is responsible for routing functions to either
Multiprocessor Subsystem (MSS) IOs or to the FPGA fabric, where they
can either interface with custom RTL or be routed to the FPGA fabric's
IOs. Document it.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
"mss-top-sysreg" contains clocks, pinctrl, resets, an interrupt controller
and more. At this point, only the reset controller child is described as
that's all that is described by the existing bindings.
The clock controller already has a dedicated node, and will retain it as
there are other clock regions, so like the mailbox, a compatible-based
lookup of the syscon is sufficient to keep the clock driver working as
before, so no child is needed. There's also an interrupt multiplexing
service provided by this syscon, for which there is work in progress at
[1].
Link: https://lore.kernel.org/linux-gpio/20240723-uncouple-enforcer-7c48e4a4fefe@wendy/ [1]
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>