drivers: scmi-msg: support performance domains for DVFS

Implement some of the SCMI performance domain management messages
in scmi-msg drivers to support basic DVFS scenario.

Co-developed-by: Etienn

drivers: scmi-msg: support performance domains for DVFS

Implement some of the SCMI performance domain management messages
in scmi-msg drivers to support basic DVFS scenario.

Co-developed-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Pascal Paillet <p.paillet@foss.st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@foss.st.com>

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drivers: scmi-msg: add support for clock using generic clock framework

Integrating the clock framework with SCMI allows to avoid boilerplate
code to do so in platform specific files. This patch adds

drivers: scmi-msg: add support for clock using generic clock framework

Integrating the clock framework with SCMI allows to avoid boilerplate
code to do so in platform specific files. This patch adds a generic
layer that uses the generic clock framework to access and expose clocks.
SCMI clocks can be added from platform code using scmi_clk_add().
A new CFG_SCMI_MSG_USE_CLK configuration option is added to enable
this generic clock support.

Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Signed-off-by: Thomas Perrot <thomas.perrot@bootlin.com>
Acked-by: Etienne Carriere <etienne.carriere@linaro.org>

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drivers: scmi-msg: add SCMI MSG message protocol

Implements MSG header protocol to handle SCMI messages. MSG header
protocol was introduced in Linux kernel v5.15 [1]. It relies on normal
cached shar

drivers: scmi-msg: add SCMI MSG message protocol

Implements MSG header protocol to handle SCMI messages. MSG header
protocol was introduced in Linux kernel v5.15 [1]. It relies on normal
cached shared memory buffer using a 32bit header followed by the SCMI
message payload.

To support this message interface, the SCMI PTA defines a new capability
and a new command. Capability PTA_SCMI_CAPS_MSG_HEADER allows client and
service to negotiate the desired transport configuration. Command
PTA_SCMI_CMD_PROCESS_MSG_CHANNEL allows client to request processing
of a message sent based on that message exchange protocol.

Platforms shall enable configuration switch CFG_SCMI_MSG_SHM_MSG to have
their SCMI service supporting that communication protocol.

Link: [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f301bba0ca7392d16a6ea4f1d264a91f1fadea1a
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

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drivers: scmi-msg: add SCMI Voltage Domain protocol

SCMI Voltage Domain protocol in defined in the SCMI specification
since its version 3 [1]. This protocol allows a SCMI server to expose
voltage re

drivers: scmi-msg: add SCMI Voltage Domain protocol

SCMI Voltage Domain protocol in defined in the SCMI specification
since its version 3 [1]. This protocol allows a SCMI server to expose
voltage regulator control services. The current specification defines
services to discover the exposed regulators, to enable/disable them
and to set/get the regulator voltage level.

The protocol driver is embedded upon configuration switch
CFG_SCMI_MSG_VOLTAGE_DOMAIN.

Link: [1] https://developer.arm.com/documentation/den0056/c
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Acked-by: Jerome Forissier <jerome@forissier.org>

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drivers/scmi-msg: smt entry points for incoming messages

This change implements SCMI channels for reading a SCMI message from a
shared memory and call the SCMI message drivers to route the message
t

drivers/scmi-msg: smt entry points for incoming messages

This change implements SCMI channels for reading a SCMI message from a
shared memory and call the SCMI message drivers to route the message
to the target platform services.

SMT refers to the shared memory management protocol which is used
to get/put message/response in shared memory. SMT is a 28byte header
stating shared memory state and exchanged protocol data.

The processing entry for a SCMI message can be a secure interrupt
(CFG_SCMI_MSG_SMT_INTERRUPT_ENTRY=y), and fastcall SMC
(CFG_SCMI_MSG_SMT_FASTCALL_ENTRY=y) or a threaded execution
context entry (CFG_SCMI_MSG_SMT_THREAD_ENTRY=y).

SMT description in this implementation is based on the SCP-firmware
implementation [1].

Link: [1] https://github.com/ARM-software/SCP-firmware.git

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

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drivers/scmi-msg: support for reset domain protocol

Adds SCMI reset domain protocol support in the SCMI message drivers
as defined in SCMI specification v2.0 [1]. Not all the messages
defined in the

drivers/scmi-msg: support for reset domain protocol

Adds SCMI reset domain protocol support in the SCMI message drivers
as defined in SCMI specification v2.0 [1]. Not all the messages
defined in the specification are supported.

Embedded upon CFG_SCMI_MSG_RESET_DOMAIN=y.

scmi_msg_get_rd_handler() sanitizes the message_id value
against any speculative use of reset domain ID as a index since by
SCMI specification, IDs are indices.

SCMI resource in this implementation are dumped or inspired by the
SCP-firmware implementation [2] of the SCMI protocol, server side.

Link: [1] http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/DEN0056A_System_Control_and_Management_Interface.pdf
Link: [2] https://github.com/ARM-software/SCP-firmware.git

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

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drivers/scmi-msg: support for clock protocol

Adds SCMI clock protocol support in the SCMI message drivers as
defined in SCMI specification v2.0 [1]. Not all the messages
defined in the specification

drivers/scmi-msg: support for clock protocol

Adds SCMI clock protocol support in the SCMI message drivers as
defined in SCMI specification v2.0 [1]. Not all the messages
defined in the specification are supported.

Embedded upon CFG_SCMI_MSG_CLOCK=y.

Platform can provide one of the plat_scmi_clock_*() handler for the
supported operations set/get state/rate and others.

scmi_msg_get_clock_handler() sanitizes the message_id value
against any speculative use of clock ID as a index since by
SCMI specification, IDs are indices.

SCMI resource in this implementation are dumped or inspired by the
SCP-firmware implementation [2] of the SCMI protocol, server side.

Link: [1] http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/DEN0056A_System_Control_and_Management_Interface.pdf
Link: [2] https://github.com/ARM-software/SCP-firmware.git

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

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drivers/scmi-msg: driver for processing scmi messages

This change introduces drivers to allow a platform to create a SCMI
service and register handlers for client request (SCMI agent) on
system reso

drivers/scmi-msg: driver for processing scmi messages

This change introduces drivers to allow a platform to create a SCMI
service and register handlers for client request (SCMI agent) on
system resources. This is the first piece of the drivers: an entry
function, the SCMI base protocol support and helpers for create
the response message.

With this change, scmi_process_message() is the entry function to
process an incoming SCMI message. The function expect the message
is already copied from shared memory into secure memory. The message
structure stores message reference and output buffer reference where
response message shall be stored.

scmi_process_message() calls the SCMI protocol driver according to
the protocol ID in the message. The SCMI protocol driver will call
defined platform handlers according to the message content.

This change introduces only the SCMI base protocol as defined in
SCMI specification v2.0 [1]. Not all the messages defined
in the specification are supported.

SCMI resource in this implementation are dumped or inspired by the
SCP-firmware implementation [2] of the SCMI protocol, server side.

Link: [1] http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/DEN0056A_System_Control_and_Management_Interface.pdf
Link: [2] https://github.com/ARM-software/SCP-firmware.git

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

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