Re: [PATCH v2 1/3] firmware: scmi: voltage regulator

On 2/19/21 10:33 PM, Etienne Carriere wrote:

Implement voltage regulators interfaced by the SCMI voltage domain protocol. The DT bindings are defined in the Linux kernel since SCMI voltage domain and regulators patches [1] and [2] integration in v5.11-rc7.

Link: [1] https://protect2.fireeye.com/v1/url?k=472c44bf-18b77dae-472dcff0-0cc47a31cdb... Link: [2] https://protect2.fireeye.com/v1/url?k=8c3fa7e5-d3a49ef4-8c3e2caa-0cc47a31cdb...

Signed-off-by: Etienne Carriere etienne.carriere@linaro.org

Reviewed-by: Jaehoon Chung jh80.chung@samsung.com

Best Regards, Jaehoon Chung

---

Changes in v2:

• no change

---

doc/device-tree-bindings/arm/arm,scmi.txt | 34 +++++ drivers/firmware/scmi/scmi_agent-uclass.c | 35 ++++- drivers/power/regulator/Kconfig | 8 + drivers/power/regulator/Makefile | 1 + drivers/power/regulator/scmi_regulator.c | 170 ++++++++++++++++++++++ include/scmi_protocols.h | 113 ++++++++++++++ 6 files changed, 359 insertions(+), 2 deletions(-) create mode 100644 drivers/power/regulator/scmi_regulator.c

diff --git a/doc/device-tree-bindings/arm/arm,scmi.txt b/doc/device-tree-bindings/arm/arm,scmi.txt index 1f293ea24..a76124f4a 100644 --- a/doc/device-tree-bindings/arm/arm,scmi.txt +++ b/doc/device-tree-bindings/arm/arm,scmi.txt @@ -62,6 +62,20 @@ Required properties:

• #power-domain-cells : Should be 1. Contains the device or the power domain ID value used by SCMI commands.

+Regulator bindings for the SCMI Regulator based on SCMI Message Protocol +------------------------------------------------------------ +An SCMI Regulator is permanently bound to a well defined SCMI Voltage Domain, +and should be always positioned as a root regulator. +It does not support any current operation.

+SCMI Regulators are grouped under a 'regulators' node which in turn is a child +of the SCMI Voltage protocol node inside the desired SCMI instance node.

+This binding uses the common regulator binding[6].

+Required properties:

• • reg : shall identify an existent SCMI Voltage Domain.

Sensor bindings for the sensors based on SCMI Message Protocol

SCMI provides an API to access the various sensors on the SoC. @@ -105,6 +119,7 @@ Required sub-node properties: [3] Documentation/devicetree/bindings/thermal/thermal.txt [4] Documentation/devicetree/bindings/sram/sram.yaml [5] Documentation/devicetree/bindings/reset/reset.txt +[6] Documentation/devicetree/bindings/regulator/regulator.yaml

Example:

@@ -169,6 +184,25 @@ firmware { reg = <0x16>; #reset-cells = <1>; };

• scmi_voltage: protocol@17 {
  

• 	reg = <0x17>;
  

• 	regulators {
  

• 		regulator_devX: regulator@0 {
  

• 			reg = <0x0>;
  

• 			regulator-max-microvolt = <3300000>;
  

• 		};
  

• 		regulator_devY: regulator@9 {
  

• 			reg = <0x9>;
  

• 			regulator-min-microvolt = <500000>;
  

• 			regulator-max-microvolt = <4200000>;
  

• 		};
  

• 		...
  

• 	};
  

• };
  

  };

};

diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c index 516e690ac..03d236426 100644 --- a/drivers/firmware/scmi/scmi_agent-uclass.c +++ b/drivers/firmware/scmi/scmi_agent-uclass.c @@ -50,6 +50,29 @@ int scmi_to_linux_errno(s32 scmi_code) return -EPROTO; }

+static int regulator_devices_bind(struct udevice *dev, struct driver *drv,

• 		  ofnode protocol_node)
  

+{

• ofnode regulators_node;
• ofnode node;
• int ret;
• regulators_node = ofnode_find_subnode(protocol_node, "regulators");
• if (!ofnode_valid(regulators_node)) {

• dev_err(dev, "regulators subnode not found\n");
  

• return -ENXIO;
  

• }
• ofnode_for_each_subnode(node, regulators_node) {

• ret = device_bind(dev, drv, ofnode_get_name(node), NULL, node,
  

• 		  NULL);
  

• if (ret)
  

• 	return ret;
  

• }
• return 0;

+}

/*

• SCMI agent devices binds devices of various uclasses depeding on
• the FDT description. scmi_bind_protocol() is a generic bind sequence

@@ -79,6 +102,10 @@ static int scmi_bind_protocols(struct udevice *dev) if (IS_ENABLED(CONFIG_RESET_SCMI)) drv = DM_DRIVER_GET(scmi_reset_domain); break;

• case SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN:
  

• 	if (IS_ENABLED(CONFIG_DM_REGULATOR_SCMI))
  

• 		drv = DM_DRIVER_GET(scmi_voltage_domain);
  

• 	break;
  

  default: break; }

@@ -89,8 +116,12 @@ static int scmi_bind_protocols(struct udevice *dev) continue; }

• ret = device_bind(dev, drv, ofnode_get_name(node), NULL, node,
  

• 		  NULL);
  

• if (protocol_id == SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN)
  

• 	ret = regulator_devices_bind(dev, drv, node);
  

• else
  

• 	ret = device_bind(dev, drv, ofnode_get_name(node),
  

• 			  NULL, node, NULL);
  

• if (ret) break; }

diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig index fbbea18c7..5d6180229 100644 --- a/drivers/power/regulator/Kconfig +++ b/drivers/power/regulator/Kconfig @@ -353,3 +353,11 @@ config DM_REGULATOR_TPS65941 TPS65941 series of PMICs have 5 single phase BUCKs that can also be configured in multi phase modes & 4 LDOs. The driver implements get/set api for value and enable.

+config DM_REGULATOR_SCMI

• bool "Enable driver for SCMI voltage domain regulators"
• depends on DM_REGULATOR
• select SCMI_AGENT

•    help
  

•      Enable this option if you want to support regulators exposed through
  

•  the SCMI voltage domain protocol by a SCMI server.
  

diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile index 9d58112dc..b2f5972ea 100644 --- a/drivers/power/regulator/Makefile +++ b/drivers/power/regulator/Makefile @@ -30,3 +30,4 @@ obj-$(CONFIG_DM_REGULATOR_TPS65910) += tps65910_regulator.o obj-$(CONFIG_DM_REGULATOR_TPS62360) += tps62360_regulator.o obj-$(CONFIG_$(SPL_)DM_REGULATOR_STPMIC1) += stpmic1.o obj-$(CONFIG_DM_REGULATOR_TPS65941) += tps65941_regulator.o +obj-$(CONFIG_DM_REGULATOR_SCMI) += scmi_regulator.o diff --git a/drivers/power/regulator/scmi_regulator.c b/drivers/power/regulator/scmi_regulator.c new file mode 100644 index 000000000..072a978a8 --- /dev/null +++ b/drivers/power/regulator/scmi_regulator.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • Copyright (C) 2020-2021 Linaro Limited
• */

+#include <common.h> +#include <dm.h> +#include <errno.h> +#include <scmi_agent.h> +#include <scmi_protocols.h> +#include <asm/types.h> +#include <dm/device.h> +#include <dm/device_compat.h> +#include <linux/kernel.h> +#include <power/regulator.h>

+/**

• • struct scmi_regulator_platdata - Platform data for a scmi voltage domain regulator
• • @domain_id: ID representing the regulator for the related SCMI agent
• */

+struct scmi_regulator_platdata {

• u32 domain_id;

+};

+static int scmi_voltd_set_enable(struct udevice *dev, bool enable) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• struct scmi_voltd_config_set_in in = {

• .domain_id = pdata->domain_id,
  

• .config = enable ? SCMI_VOLTD_CONFIG_ON : SCMI_VOLTD_CONFIG_OFF,
  

• };
• struct scmi_voltd_config_set_out out;
• struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN,

• 			  SCMI_VOLTAGE_DOMAIN_CONFIG_SET,
  

• 			  in, out);
  

• int ret;
• ret = devm_scmi_process_msg(dev->parent, &msg);
• if (ret)

• return ret;
  

• ret = scmi_to_linux_errno(out.status);
• if (ret)

• return ret;
  

• return ret;

+}

+static int scmi_voltd_get_enable(struct udevice *dev) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• struct scmi_voltd_config_get_in in = {

• .domain_id = pdata->domain_id,
  

• };
• struct scmi_voltd_config_get_out out;
• struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN,

• 			  SCMI_VOLTAGE_DOMAIN_CONFIG_GET,
  

• 			  in, out);
  

• int ret;
• ret = devm_scmi_process_msg(dev->parent, &msg);
• if (ret < 0)

• return ret;
  

• ret = scmi_to_linux_errno(out.status);
• if (ret < 0)

• return ret;
  

• return out.config == SCMI_VOLTD_CONFIG_ON;

+}

+static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• struct scmi_voltd_level_set_in in = {

• .domain_id = pdata->domain_id,
  

• .voltage_level = uV,
  

• };
• struct scmi_voltd_level_set_out out;
• struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN,

• 			  SCMI_VOLTAGE_DOMAIN_LEVEL_SET,
  

• 			  in, out);
  

• int ret;
• ret = devm_scmi_process_msg(dev->parent, &msg);
• if (ret < 0)

• return ret;
  

• return scmi_to_linux_errno(out.status);

+}

+static int scmi_voltd_get_voltage_level(struct udevice *dev) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• struct scmi_voltd_level_get_in in = {

• .domain_id = pdata->domain_id,
  

• };
• struct scmi_voltd_level_get_out out;
• struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN,

• 			  SCMI_VOLTAGE_DOMAIN_LEVEL_GET,
  

• 			  in, out);
  

• int ret;
• ret = devm_scmi_process_msg(dev->parent, &msg);
• if (ret < 0)

• return ret;
  

• ret = scmi_to_linux_errno(out.status);
• if (ret < 0)

• return ret;
  

• return out.voltage_level;

+}

+static int scmi_regulator_of_to_plat(struct udevice *dev) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• fdt_addr_t reg;
• reg = dev_read_addr(dev);
• if (reg == FDT_ADDR_T_NONE)

• return -EINVAL;
  

• pdata->domain_id = (u32)reg;
• return 0;

+}

+static int scmi_regulator_probe(struct udevice *dev) +{

• struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
• struct scmi_voltd_attr_in in = { 0 };
• struct scmi_voltd_attr_out out = { 0 };
• struct scmi_msg scmi_msg = {

• .protocol_id = SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN,
  

• .message_id = SCMI_VOLTAGE_DOMAIN_ATTRIBUTES,
  

• .in_msg = (u8 *)&in,
  

• .in_msg_sz = sizeof(in),
  

• .out_msg = (u8 *)&out,
  

• .out_msg_sz = sizeof(out),
  

• };
• int ret;
• /* Check voltage domain is known from SCMI server */
• in.domain_id = pdata->domain_id;
• ret = devm_scmi_process_msg(dev->parent, &scmi_msg);
• if (ret) {

• dev_err(dev, "Failed to query voltage domain %u: %d\n",
  

• 	pdata->domain_id, ret);
  

• return -ENXIO;
  

• }
• return 0;

+}

+static const struct dm_regulator_ops scmi_voltd_ops = {

• .get_value = scmi_voltd_get_voltage_level,
• .set_value = scmi_voltd_set_voltage_level,
• .get_enable = scmi_voltd_get_enable,
• .set_enable = scmi_voltd_set_enable,

+};

+U_BOOT_DRIVER(scmi_voltage_domain) = {

• .name = "scmi_voltage_domain",
• .id = UCLASS_REGULATOR,
• .ops = &scmi_voltd_ops,
• .probe = scmi_regulator_probe,
• .of_to_plat = scmi_regulator_of_to_plat,
• .plat_auto = sizeof(struct scmi_regulator_platdata),

+}; diff --git a/include/scmi_protocols.h b/include/scmi_protocols.h index ccab97c96..2db71697e 100644 --- a/include/scmi_protocols.h +++ b/include/scmi_protocols.h @@ -23,6 +23,7 @@ enum scmi_std_protocol { SCMI_PROTOCOL_ID_CLOCK = 0x14, SCMI_PROTOCOL_ID_SENSOR = 0x15, SCMI_PROTOCOL_ID_RESET_DOMAIN = 0x16,

• SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN = 0x17,

};

enum scmi_status_code { @@ -176,4 +177,116 @@ struct scmi_rd_reset_out { s32 status; };

+/*

• • SCMI Voltage Domain Protocol
• */

+enum scmi_voltage_domain_message_id {

• SCMI_VOLTAGE_DOMAIN_ATTRIBUTES = 0x3,
• SCMI_VOLTAGE_DOMAIN_CONFIG_SET = 0x5,
• SCMI_VOLTAGE_DOMAIN_CONFIG_GET = 0x6,
• SCMI_VOLTAGE_DOMAIN_LEVEL_SET = 0x7,
• SCMI_VOLTAGE_DOMAIN_LEVEL_GET = 0x8,

+};

+#define SCMI_VOLTD_NAME_LEN 16

+#define SCMI_VOLTD_CONFIG_MASK GENMASK(3, 0) +#define SCMI_VOLTD_CONFIG_OFF 0 +#define SCMI_VOLTD_CONFIG_ON 0x7

+/**

• • struct scmi_voltd_attr_in - Payload for VOLTAGE_DOMAIN_ATTRIBUTES message
• • @domain_id: SCMI voltage domain ID
• */

+struct scmi_voltd_attr_in {

• u32 domain_id;

+};

+/**

• • struct scmi_voltd_attr_out - Payload for VOLTAGE_DOMAIN_ATTRIBUTES response
• • @status: SCMI command status
• • @attributes: Retrieved attributes of the voltage domain
• • @name: Voltage domain name
• */

+struct scmi_voltd_attr_out {

• s32 status;
• u32 attributes;
• char name[SCMI_VOLTD_NAME_LEN];

+};

+/**

• • struct scmi_voltd_config_set_in - Message payload for VOLTAGE_CONFIG_SET cmd
• • @domain_id: SCMI voltage domain ID
• • @config: Configuration data of the voltage domain
• */

+struct scmi_voltd_config_set_in {

• u32 domain_id;
• u32 config;

+};

+/**

• • struct scmi_voltd_config_set_out - Response for VOLTAGE_CONFIG_SET command
• • @status: SCMI command status
• */

+struct scmi_voltd_config_set_out {

• s32 status;

+};

+/**

• • struct scmi_voltd_config_get_in - Message payload for VOLTAGE_CONFIG_GET cmd
• • @domain_id: SCMI voltage domain ID
• */

+struct scmi_voltd_config_get_in {

• u32 domain_id;

+};

+/**

• • struct scmi_voltd_config_get_out - Response for VOLTAGE_CONFIG_GET command
• • @status: SCMI command status
• • @config: Configuration data of the voltage domain
• */

+struct scmi_voltd_config_get_out {

• s32 status;
• u32 config;

+};

+/**

• • struct scmi_voltd_level_set_in - Message payload for VOLTAGE_LEVEL_SET cmd
• • @domain_id: SCMI voltage domain ID
• • @flags: Parameter flags for configuring target level
• • @voltage_level: Target voltage level in microvolts (uV)
• */

+struct scmi_voltd_level_set_in {

• u32 domain_id;
• u32 flags;
• s32 voltage_level;

+};

+/**

• • struct scmi_voltd_level_set_out - Response for VOLTAGE_LEVEL_SET command
• • @status: SCMI command status
• */

+struct scmi_voltd_level_set_out {

• s32 status;

+};

+/**

• • struct scmi_voltd_level_get_in - Message payload for VOLTAGE_LEVEL_GET cmd
• • @domain_id: SCMI voltage domain ID
• */

+struct scmi_voltd_level_get_in {

• u32 domain_id;

+};

+/**

• • struct scmi_voltd_level_get_out - Response for VOLTAGE_LEVEL_GET command
• • @status: SCMI command status
• • @voltage_level: Voltage level in microvolts (uV)
• */

+struct scmi_voltd_level_get_out {

• s32 status;
• s32 voltage_level;

+};

#endif /* _SCMI_PROTOCOLS_H */