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* [PATCH v4 0/4] firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support
@ 2023-08-08 18:25 Oleksii Moisieiev
  2023-08-08 18:25 ` [PATCH v4 2/4] " Oleksii Moisieiev
                   ` (4 more replies)
  0 siblings, 5 replies; 14+ messages in thread
From: Oleksii Moisieiev @ 2023-08-08 18:25 UTC (permalink / raw)
  To: sudeep.holla@arm.com
  Cc: Oleksii Moisieiev, Cristian Marussi, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Linus Walleij,
	linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org

This Patch series is intended to introduce the generic driver for
pin controls over SCMI protocol, provided in the latest beta version of DEN0056 [0].

On ARM-based systems, a separate Cortex-M based System Control Processor (SCP)
provides control on pins, as well as with power, clocks, reset controllers. In this case,
kernel should use one of the possible transports, described in [0] to access SCP and
control clocks/power-domains etc. This driver is using SMC transport to communicate with SCP via
SCMI protocol and access to the Pin Control Subsystem.

The provided driver consists of 2 parts:
 - firmware/arm_scmi/pinctrl.c - the SCMI pinctrl protocol inmplementation
   responsible for the communication with SCP firmware.

 - drivers/pinctrl/pinctrl-scmi.c - pinctrl driver, which is using pinctrl
  protocol implementation to access all necessary data.

Configuration:
The scmi-pinctrl driver can be configured using DT bindings.
For example:
/ {
	cpu_scp_shm: scp-shmem@0x53FF0000 {
		compatible = "arm,scmi-shmem";
		reg = <0x0 0x53FF0000 0x0 0x1000>;
	};

	firmware {
		scmi {
			compatible = "arm,scmi-smc";
			arm,smc-id = <0x82000002>;
			shmem = <&cpu_scp_shm>;
			#address-cells = <1>;
			#size-cells = <0>;

			scmi_pinctrl: protocol@19 {
				reg = <0x18>;
				#pinctrl-cells = <0>;

				i2c2_pins: i2c2 {
					groups = "i2c2_a";
					function = "i2c2";
				};
			};
		};
	};
};

&pfc {
	/delete-node/i2c2;
};

So basically, it's enough to move pfc subnode, which configures pin group that should work through
SCMI protocol to scmi_pinctrl node. The current driver implementation is using generic pinctrl dt_node
format.

I've tested this driver on the Renesas H3ULCB Kingfisher board with pinctrl driver ported to the
Arm-trusted-firmware. Unfortunately, not all hardware was possible to test because the Renesas
pinctrl driver has gaps in pins and groups numeration, when Spec [0] requires pins, groups and
functions numerations to be 0..n without gaps.

Also, sharing link to the ATF pinctrl driver I used for testing:
https://github.com/oleksiimoisieiev/arm-trusted-firmware/tree/pinctrl_rcar_m3_up

[0] https://developer.arm.com/documentation/den0056/latest

---
Changes v3 -> v4:
   - Fixed MAINTAINERS file description
   - adjusted pinctrl ops position and callback names
   - add trailing coma in scmi_protocol list
   - removed unneeded pi checks
   - corrected selector check
   - resource allocation refactoring
   - scmi_*_info swap params to generate better code
   - style, add trailing coma in definitions
   - reworked protocol@19 format in device-tree bindings
   - ordered config option and object file alphabetically
   - rephrased PINCTRL_SCMI config description
   - formatting fixes, removed blank lines after get_drvdata call
   - code style adjustments
   - add set_drvdata call
   - removed goto label
   - refactoring of the devm resource management
   - removed pctldev != NULL check
   - fix parameter name in pinconf-group-get
   - probe function refactoring
   - removed unneeded pmx checks

Changes v2 -> v3:
   - update get_name calls as suggested by Cristian Marussi
   - fixing comments
   - refactoring of the dt_bindings according to the comments
Changes v1 -> v2:
   - rebase patches to the latest kernel version
   - use protocol helpers in the pinctrl scmi protocol driver implementation
   - reworked pinctrl_ops. Removed similar calls to simplify the interface
   - implementation of the .instance_deinit callback to properly clean resources
   - add description of the pinctrl protocol to the device-tree schema

---
Cristian Marussi (1):
  firmware: arm_scmi: Add optional flags to extended names helper

Oleksii Moisieiev (3):
  firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support
  pinctrl: Implementation of the generic scmi-pinctrl driver
  dt-bindings: firmware: arm,scmi: Add support for pinctrl protocol

 .../bindings/firmware/arm,scmi.yaml           |  53 ++
 MAINTAINERS                                   |   7 +
 drivers/firmware/arm_scmi/Makefile            |   2 +-
 drivers/firmware/arm_scmi/clock.c             |   2 +-
 drivers/firmware/arm_scmi/driver.c            |   9 +-
 drivers/firmware/arm_scmi/perf.c              |   3 +-
 drivers/firmware/arm_scmi/pinctrl.c           | 791 ++++++++++++++++++
 drivers/firmware/arm_scmi/power.c             |   2 +-
 drivers/firmware/arm_scmi/powercap.c          |   2 +-
 drivers/firmware/arm_scmi/protocols.h         |   4 +-
 drivers/firmware/arm_scmi/reset.c             |   3 +-
 drivers/firmware/arm_scmi/sensors.c           |   2 +-
 drivers/firmware/arm_scmi/voltage.c           |   2 +-
 drivers/pinctrl/Kconfig                       |  11 +
 drivers/pinctrl/Makefile                      |   1 +
 drivers/pinctrl/pinctrl-scmi.c                | 442 ++++++++++
 include/linux/scmi_protocol.h                 |  42 +
 17 files changed, 1367 insertions(+), 11 deletions(-)
 create mode 100644 drivers/firmware/arm_scmi/pinctrl.c
 create mode 100644 drivers/pinctrl/pinctrl-scmi.c

-- 
2.25.1

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2023-08-25  1:04 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-08-08 18:25 [PATCH v4 0/4] firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support Oleksii Moisieiev
2023-08-08 18:25 ` [PATCH v4 2/4] " Oleksii Moisieiev
2023-08-16 12:21   ` Cristian Marussi
2023-08-08 18:25 ` [PATCH v4 3/4] pinctrl: Implementation of the generic scmi-pinctrl driver Oleksii Moisieiev
2023-08-10  8:43   ` Linus Walleij
2023-08-16 12:25   ` Cristian Marussi
2023-08-23  4:13   ` AKASHI Takahiro
2023-08-23 13:34     ` Cristian Marussi
2023-08-08 18:25 ` [PATCH v4 1/4] firmware: arm_scmi: Add optional flags to extended names helper Oleksii Moisieiev
2023-08-16 10:27   ` Cristian Marussi
2023-08-08 18:25 ` [PATCH v4 4/4] dt-bindings: firmware: arm,scmi: Add support for pinctrl protocol Oleksii Moisieiev
2023-08-21 16:57   ` Rob Herring
2023-08-25  1:03   ` AKASHI Takahiro
2023-08-16 12:30 ` [PATCH v4 0/4] firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support Cristian Marussi

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