drivers/firmware/scmi/sandbox-scmi_agent.c - filogic/uboot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2020, Linaro Limited
  */

 #define LOG_CATEGORY UCLASS_SCMI_AGENT

 #include <common.h>
 #include <dm.h>
 #include <malloc.h>
 #include <scmi_agent.h>
 #include <scmi_agent-uclass.h>
 #include <scmi_protocols.h>
 #include <asm/io.h>
 #include <asm/scmi_test.h>
 #include <dm/device_compat.h>

 /*
  * The sandbox SCMI agent driver simulates to some extend a SCMI message
  * processing. It simulates few of the SCMI services for some of the
  * SCMI protocols embedded in U-Boot. Currently:
  * - SCMI clock protocol: emulate 2 agents each exposing few clocks
  * - SCMI reset protocol: emulate 1 agents each exposing a reset
  *
  * Agent #0 simulates 2 clocks and 1 reset domain.
  * See IDs in scmi0_clk[]/scmi0_reset[] and "sandbox-scmi-agent@0" in test.dts.
  *
  * Agent #1 simulates 1 clock.
  * See IDs in scmi1_clk[] and "sandbox-scmi-agent@1" in test.dts.
  *
  * All clocks are default disabled and reset levels down.
  *
  * This Driver exports sandbox_scmi_service_ct() for the test sequence to
  * get the state of the simulated services (clock state, rate, ...) and
  * check back-end device state reflects the request send through the
  * various uclass devices, as clocks and reset controllers.
  */

 #define SANDBOX_SCMI_AGENT_COUNT	2

 static struct sandbox_scmi_clk scmi0_clk[] = {
 	{ .id = 7, .rate = 1000 },
 	{ .id = 3, .rate = 333 },
 };

 static struct sandbox_scmi_reset scmi0_reset[] = {
 	{ .id = 3 },
 };

 static struct sandbox_scmi_clk scmi1_clk[] = {
 	{ .id = 1, .rate = 44 },
 };

 /* The list saves to simulted end devices references for test purpose */
 struct sandbox_scmi_agent *sandbox_scmi_agent_list[SANDBOX_SCMI_AGENT_COUNT];

 static struct sandbox_scmi_service sandbox_scmi_service_state = {
 	.agent = sandbox_scmi_agent_list,
 	.agent_count = SANDBOX_SCMI_AGENT_COUNT,
 };

 struct sandbox_scmi_service *sandbox_scmi_service_ctx(void)
 {
 	return &sandbox_scmi_service_state;
 }

 static void debug_print_agent_state(struct udevice *dev, char *str)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);

 	dev_dbg(dev, "Dump sandbox_scmi_agent %u: %s\n", agent->idx, str);
 	dev_dbg(dev, " scmi%u_clk   (%zu): %d/%ld, %d/%ld, %d/%ld, ...\n",
 		agent->idx,
 		agent->clk_count,
 		agent->clk_count ? agent->clk[0].enabled : -1,
 		agent->clk_count ? agent->clk[0].rate : -1,
 		agent->clk_count > 1 ? agent->clk[1].enabled : -1,
 		agent->clk_count > 1 ? agent->clk[1].rate : -1,
 		agent->clk_count > 2 ? agent->clk[2].enabled : -1,
 		agent->clk_count > 2 ? agent->clk[2].rate : -1);
 	dev_dbg(dev, " scmi%u_reset (%zu): %d, %d, ...\n",
 		agent->idx,
 		agent->reset_count,
 		agent->reset_count ? agent->reset[0].asserted : -1,
 		agent->reset_count > 1 ? agent->reset[1].asserted : -1);
 };

 static struct sandbox_scmi_clk *get_scmi_clk_state(uint agent_id, uint clock_id)
 {
 	struct sandbox_scmi_clk *target = NULL;
 	size_t target_count = 0;
 	size_t n;

 	switch (agent_id) {
 	case 0:
 		target = scmi0_clk;
 		target_count = ARRAY_SIZE(scmi0_clk);
 		break;
 	case 1:
 		target = scmi1_clk;
 		target_count = ARRAY_SIZE(scmi1_clk);
 		break;
 	default:
 		return NULL;
 	}

 	for (n = 0; n < target_count; n++)
 		if (target[n].id == clock_id)
 			return target + n;

 	return NULL;
 }

 static struct sandbox_scmi_reset *get_scmi_reset_state(uint agent_id,
 						       uint reset_id)
 {
 	size_t n;

 	if (agent_id == 0) {
 		for (n = 0; n < ARRAY_SIZE(scmi0_reset); n++)
 			if (scmi0_reset[n].id == reset_id)
 				return scmi0_reset + n;
 	}

 	return NULL;
 }

 /*
  * Sandbox SCMI agent ops
  */

 static int sandbox_scmi_clock_rate_set(struct udevice *dev,
 				       struct scmi_msg *msg)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	struct scmi_clk_rate_set_in *in = NULL;
 	struct scmi_clk_rate_set_out *out = NULL;
 	struct sandbox_scmi_clk *clk_state = NULL;

 	if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||
 	    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
 		return -EINVAL;

 	in = (struct scmi_clk_rate_set_in *)msg->in_msg;
 	out = (struct scmi_clk_rate_set_out *)msg->out_msg;

 	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
 	if (!clk_state) {
 		dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

 		out->status = SCMI_NOT_FOUND;
 	} else {
 		u64 rate = ((u64)in->rate_msb << 32) + in->rate_lsb;

 		clk_state->rate = (ulong)rate;

 		out->status = SCMI_SUCCESS;
 	}

 	return 0;
 }

 static int sandbox_scmi_clock_rate_get(struct udevice *dev,
 				       struct scmi_msg *msg)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	struct scmi_clk_rate_get_in *in = NULL;
 	struct scmi_clk_rate_get_out *out = NULL;
 	struct sandbox_scmi_clk *clk_state = NULL;

 	if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||
 	    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
 		return -EINVAL;

 	in = (struct scmi_clk_rate_get_in *)msg->in_msg;
 	out = (struct scmi_clk_rate_get_out *)msg->out_msg;

 	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
 	if (!clk_state) {
 		dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

 		out->status = SCMI_NOT_FOUND;
 	} else {
 		out->rate_msb = (u32)((u64)clk_state->rate >> 32);
 		out->rate_lsb = (u32)clk_state->rate;

 		out->status = SCMI_SUCCESS;
 	}

 	return 0;
 }

 static int sandbox_scmi_clock_gate(struct udevice *dev, struct scmi_msg *msg)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	struct scmi_clk_state_in *in = NULL;
 	struct scmi_clk_state_out *out = NULL;
 	struct sandbox_scmi_clk *clk_state = NULL;

 	if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||
 	    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
 		return -EINVAL;

 	in = (struct scmi_clk_state_in *)msg->in_msg;
 	out = (struct scmi_clk_state_out *)msg->out_msg;

 	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
 	if (!clk_state) {
 		dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

 		out->status = SCMI_NOT_FOUND;
 	} else if (in->attributes > 1) {
 		out->status = SCMI_PROTOCOL_ERROR;
 	} else {
 		clk_state->enabled = in->attributes;

 		out->status = SCMI_SUCCESS;
 	}

 	return 0;
 }

 static int sandbox_scmi_rd_attribs(struct udevice *dev, struct scmi_msg *msg)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	struct scmi_rd_attr_in *in = NULL;
 	struct scmi_rd_attr_out *out = NULL;
 	struct sandbox_scmi_reset *reset_state = NULL;

 	if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||
 	    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
 		return -EINVAL;

 	in = (struct scmi_rd_attr_in *)msg->in_msg;
 	out = (struct scmi_rd_attr_out *)msg->out_msg;

 	reset_state = get_scmi_reset_state(agent->idx, in->domain_id);
 	if (!reset_state) {
 		dev_err(dev, "Unexpected reset domain ID %u\n", in->domain_id);

 		out->status = SCMI_NOT_FOUND;
 	} else {
 		memset(out, 0, sizeof(*out));
 		snprintf(out->name, sizeof(out->name), "rd%u", in->domain_id);

 		out->status = SCMI_SUCCESS;
 	}

 	return 0;
 }

 static int sandbox_scmi_rd_reset(struct udevice *dev, struct scmi_msg *msg)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	struct scmi_rd_reset_in *in = NULL;
 	struct scmi_rd_reset_out *out = NULL;
 	struct sandbox_scmi_reset *reset_state = NULL;

 	if (!msg->in_msg || msg->in_msg_sz < sizeof(*in) ||
 	    !msg->out_msg || msg->out_msg_sz < sizeof(*out))
 		return -EINVAL;

 	in = (struct scmi_rd_reset_in *)msg->in_msg;
 	out = (struct scmi_rd_reset_out *)msg->out_msg;

 	reset_state = get_scmi_reset_state(agent->idx, in->domain_id);
 	if (!reset_state) {
 		dev_err(dev, "Unexpected reset domain ID %u\n", in->domain_id);

 		out->status = SCMI_NOT_FOUND;
 	} else if (in->reset_state > 1) {
 		dev_err(dev, "Invalid reset domain input attribute value\n");

 		out->status = SCMI_INVALID_PARAMETERS;
 	} else {
 		if (in->flags & SCMI_RD_RESET_FLAG_CYCLE) {
 			if (in->flags & SCMI_RD_RESET_FLAG_ASYNC) {
 				out->status = SCMI_NOT_SUPPORTED;
 			} else {
 				/* Ends deasserted whatever current state */
 				reset_state->asserted = false;
 				out->status = SCMI_SUCCESS;
 			}
 		} else {
 			reset_state->asserted = in->flags &
 						SCMI_RD_RESET_FLAG_ASSERT;

 			out->status = SCMI_SUCCESS;
 		}
 	}

 	return 0;
 }

 static int sandbox_scmi_test_process_msg(struct udevice *dev,
 					 struct scmi_msg *msg)
 {
 	switch (msg->protocol_id) {
 	case SCMI_PROTOCOL_ID_CLOCK:
 		switch (msg->message_id) {
 		case SCMI_CLOCK_RATE_SET:
 			return sandbox_scmi_clock_rate_set(dev, msg);
 		case SCMI_CLOCK_RATE_GET:
 			return sandbox_scmi_clock_rate_get(dev, msg);
 		case SCMI_CLOCK_CONFIG_SET:
 			return sandbox_scmi_clock_gate(dev, msg);
 		default:
 			break;
 		}
 		break;
 	case SCMI_PROTOCOL_ID_RESET_DOMAIN:
 		switch (msg->message_id) {
 		case SCMI_RESET_DOMAIN_ATTRIBUTES:
 			return sandbox_scmi_rd_attribs(dev, msg);
 		case SCMI_RESET_DOMAIN_RESET:
 			return sandbox_scmi_rd_reset(dev, msg);
 		default:
 			break;
 		}
 		break;
 	case SCMI_PROTOCOL_ID_BASE:
 	case SCMI_PROTOCOL_ID_POWER_DOMAIN:
 	case SCMI_PROTOCOL_ID_SYSTEM:
 	case SCMI_PROTOCOL_ID_PERF:
 	case SCMI_PROTOCOL_ID_SENSOR:
 		*(u32 *)msg->out_msg = SCMI_NOT_SUPPORTED;
 		return 0;
 	default:
 		break;
 	}

 	dev_err(dev, "%s(%s): Unhandled protocol_id %#x/message_id %#x\n",
 		__func__, dev->name, msg->protocol_id, msg->message_id);

 	if (msg->out_msg_sz < sizeof(u32))
 		return -EINVAL;

 	/* Intentionnaly report unhandled IDs through the SCMI return code */
 	*(u32 *)msg->out_msg = SCMI_PROTOCOL_ERROR;
 	return 0;
 }

 static int sandbox_scmi_test_remove(struct udevice *dev)
 {
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);

 	debug_print_agent_state(dev, "removed");

 	/* We only need to dereference the agent in the context */
 	sandbox_scmi_service_ctx()->agent[agent->idx] = NULL;

 	return 0;
 }

 static int sandbox_scmi_test_probe(struct udevice *dev)
 {
 	static const char basename[] = "sandbox-scmi-agent@";
 	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
 	const size_t basename_size = sizeof(basename) - 1;

 	if (strncmp(basename, dev->name, basename_size))
 		return -ENOENT;

 	switch (dev->name[basename_size]) {
 	case '0':
 		*agent = (struct sandbox_scmi_agent){
 			.idx = 0,
 			.clk = scmi0_clk,
 			.clk_count = ARRAY_SIZE(scmi0_clk),
 			.reset = scmi0_reset,
 			.reset_count = ARRAY_SIZE(scmi0_reset),
 		};
 		break;
 	case '1':
 		*agent = (struct sandbox_scmi_agent){
 			.idx = 1,
 			.clk = scmi1_clk,
 			.clk_count = ARRAY_SIZE(scmi1_clk),
 		};
 		break;
 	default:
 		dev_err(dev, "%s(): Unexpected agent ID %s\n",
 			__func__, dev->name + basename_size);
 		return -ENOENT;
 	}

 	debug_print_agent_state(dev, "probed");

 	/* Save reference for tests purpose */
 	sandbox_scmi_service_ctx()->agent[agent->idx] = agent;

 	return 0;
 };

 static const struct udevice_id sandbox_scmi_test_ids[] = {
 	{ .compatible = "sandbox,scmi-agent" },
 	{ }
 };

 struct scmi_agent_ops sandbox_scmi_test_ops = {
 	.process_msg = sandbox_scmi_test_process_msg,
 };

 U_BOOT_DRIVER(sandbox_scmi_agent) = {
 	.name = "sandbox-scmi_agent",
 	.id = UCLASS_SCMI_AGENT,
 	.of_match = sandbox_scmi_test_ids,
 	.priv_auto	= sizeof(struct sandbox_scmi_agent),
 	.probe = sandbox_scmi_test_probe,
 	.remove = sandbox_scmi_test_remove,
 	.ops = &sandbox_scmi_test_ops,
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright (C) 2020, Linaro Limited
	*/

	#define LOG_CATEGORY UCLASS_SCMI_AGENT

	#include <common.h>
	#include <dm.h>
	#include <malloc.h>
	#include <scmi_agent.h>
	#include <scmi_agent-uclass.h>
	#include <scmi_protocols.h>
	#include <asm/io.h>
	#include <asm/scmi_test.h>
	#include <dm/device_compat.h>

	/*
	* The sandbox SCMI agent driver simulates to some extend a SCMI message
	* processing. It simulates few of the SCMI services for some of the
	* SCMI protocols embedded in U-Boot. Currently:
	* - SCMI clock protocol: emulate 2 agents each exposing few clocks
	* - SCMI reset protocol: emulate 1 agents each exposing a reset
	*
	* Agent #0 simulates 2 clocks and 1 reset domain.
	* See IDs in scmi0_clk[]/scmi0_reset[] and "sandbox-scmi-agent@0" in test.dts.
	*
	* Agent #1 simulates 1 clock.
	* See IDs in scmi1_clk[] and "sandbox-scmi-agent@1" in test.dts.
	*
	* All clocks are default disabled and reset levels down.
	*
	* This Driver exports sandbox_scmi_service_ct() for the test sequence to
	* get the state of the simulated services (clock state, rate, ...) and
	* check back-end device state reflects the request send through the
	* various uclass devices, as clocks and reset controllers.
	*/

	#define SANDBOX_SCMI_AGENT_COUNT 2

	static struct sandbox_scmi_clk scmi0_clk[] = {
	{ .id = 7, .rate = 1000 },
	{ .id = 3, .rate = 333 },
	};

	static struct sandbox_scmi_reset scmi0_reset[] = {
	{ .id = 3 },
	};

	static struct sandbox_scmi_clk scmi1_clk[] = {
	{ .id = 1, .rate = 44 },
	};

	/* The list saves to simulted end devices references for test purpose */
	struct sandbox_scmi_agent *sandbox_scmi_agent_list[SANDBOX_SCMI_AGENT_COUNT];

	static struct sandbox_scmi_service sandbox_scmi_service_state = {
	.agent = sandbox_scmi_agent_list,
	.agent_count = SANDBOX_SCMI_AGENT_COUNT,
	};

	struct sandbox_scmi_service *sandbox_scmi_service_ctx(void)
	{
	return &sandbox_scmi_service_state;
	}

	static void debug_print_agent_state(struct udevice dev, char str)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);

	dev_dbg(dev, "Dump sandbox_scmi_agent %u: %s\n", agent->idx, str);
	dev_dbg(dev, " scmi%u_clk (%zu): %d/%ld, %d/%ld, %d/%ld, ...\n",
	agent->idx,
	agent->clk_count,
	agent->clk_count ? agent->clk[0].enabled : -1,
	agent->clk_count ? agent->clk[0].rate : -1,
	agent->clk_count > 1 ? agent->clk[1].enabled : -1,
	agent->clk_count > 1 ? agent->clk[1].rate : -1,
	agent->clk_count > 2 ? agent->clk[2].enabled : -1,
	agent->clk_count > 2 ? agent->clk[2].rate : -1);
	dev_dbg(dev, " scmi%u_reset (%zu): %d, %d, ...\n",
	agent->idx,
	agent->reset_count,
	agent->reset_count ? agent->reset[0].asserted : -1,
	agent->reset_count > 1 ? agent->reset[1].asserted : -1);
	};

	static struct sandbox_scmi_clk *get_scmi_clk_state(uint agent_id, uint clock_id)
	{
	struct sandbox_scmi_clk *target = NULL;
	size_t target_count = 0;
	size_t n;

	switch (agent_id) {
	case 0:
	target = scmi0_clk;
	target_count = ARRAY_SIZE(scmi0_clk);
	break;
	case 1:
	target = scmi1_clk;
	target_count = ARRAY_SIZE(scmi1_clk);
	break;
	default:
	return NULL;
	}

	for (n = 0; n < target_count; n++)
	if (target[n].id == clock_id)
	return target + n;

	return NULL;
	}

	static struct sandbox_scmi_reset *get_scmi_reset_state(uint agent_id,
	uint reset_id)
	{
	size_t n;

	if (agent_id == 0) {
	for (n = 0; n < ARRAY_SIZE(scmi0_reset); n++)
	if (scmi0_reset[n].id == reset_id)
	return scmi0_reset + n;
	}

	return NULL;
	}

	/*
	* Sandbox SCMI agent ops
	*/

	static int sandbox_scmi_clock_rate_set(struct udevice *dev,
	struct scmi_msg *msg)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	struct scmi_clk_rate_set_in *in = NULL;
	struct scmi_clk_rate_set_out *out = NULL;
	struct sandbox_scmi_clk *clk_state = NULL;

	if (!msg->in_msg \|\| msg->in_msg_sz < sizeof(*in) \|\|
	!msg->out_msg \|\| msg->out_msg_sz < sizeof(*out))
	return -EINVAL;

	in = (struct scmi_clk_rate_set_in *)msg->in_msg;
	out = (struct scmi_clk_rate_set_out *)msg->out_msg;

	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
	if (!clk_state) {
	dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

	out->status = SCMI_NOT_FOUND;
	} else {
	u64 rate = ((u64)in->rate_msb << 32) + in->rate_lsb;

	clk_state->rate = (ulong)rate;

	out->status = SCMI_SUCCESS;
	}

	return 0;
	}

	static int sandbox_scmi_clock_rate_get(struct udevice *dev,
	struct scmi_msg *msg)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	struct scmi_clk_rate_get_in *in = NULL;
	struct scmi_clk_rate_get_out *out = NULL;
	struct sandbox_scmi_clk *clk_state = NULL;

	if (!msg->in_msg \|\| msg->in_msg_sz < sizeof(*in) \|\|
	!msg->out_msg \|\| msg->out_msg_sz < sizeof(*out))
	return -EINVAL;

	in = (struct scmi_clk_rate_get_in *)msg->in_msg;
	out = (struct scmi_clk_rate_get_out *)msg->out_msg;

	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
	if (!clk_state) {
	dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

	out->status = SCMI_NOT_FOUND;
	} else {
	out->rate_msb = (u32)((u64)clk_state->rate >> 32);
	out->rate_lsb = (u32)clk_state->rate;

	out->status = SCMI_SUCCESS;
	}

	return 0;
	}

	static int sandbox_scmi_clock_gate(struct udevice dev, struct scmi_msg msg)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	struct scmi_clk_state_in *in = NULL;
	struct scmi_clk_state_out *out = NULL;
	struct sandbox_scmi_clk *clk_state = NULL;

	if (!msg->in_msg \|\| msg->in_msg_sz < sizeof(*in) \|\|
	!msg->out_msg \|\| msg->out_msg_sz < sizeof(*out))
	return -EINVAL;

	in = (struct scmi_clk_state_in *)msg->in_msg;
	out = (struct scmi_clk_state_out *)msg->out_msg;

	clk_state = get_scmi_clk_state(agent->idx, in->clock_id);
	if (!clk_state) {
	dev_err(dev, "Unexpected clock ID %u\n", in->clock_id);

	out->status = SCMI_NOT_FOUND;
	} else if (in->attributes > 1) {
	out->status = SCMI_PROTOCOL_ERROR;
	} else {
	clk_state->enabled = in->attributes;

	out->status = SCMI_SUCCESS;
	}

	return 0;
	}

	static int sandbox_scmi_rd_attribs(struct udevice dev, struct scmi_msg msg)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	struct scmi_rd_attr_in *in = NULL;
	struct scmi_rd_attr_out *out = NULL;
	struct sandbox_scmi_reset *reset_state = NULL;

	if (!msg->in_msg \|\| msg->in_msg_sz < sizeof(*in) \|\|
	!msg->out_msg \|\| msg->out_msg_sz < sizeof(*out))
	return -EINVAL;

	in = (struct scmi_rd_attr_in *)msg->in_msg;
	out = (struct scmi_rd_attr_out *)msg->out_msg;

	reset_state = get_scmi_reset_state(agent->idx, in->domain_id);
	if (!reset_state) {
	dev_err(dev, "Unexpected reset domain ID %u\n", in->domain_id);

	out->status = SCMI_NOT_FOUND;
	} else {
	memset(out, 0, sizeof(*out));
	snprintf(out->name, sizeof(out->name), "rd%u", in->domain_id);

	out->status = SCMI_SUCCESS;
	}

	return 0;
	}

	static int sandbox_scmi_rd_reset(struct udevice dev, struct scmi_msg msg)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	struct scmi_rd_reset_in *in = NULL;
	struct scmi_rd_reset_out *out = NULL;
	struct sandbox_scmi_reset *reset_state = NULL;

	if (!msg->in_msg \|\| msg->in_msg_sz < sizeof(*in) \|\|
	!msg->out_msg \|\| msg->out_msg_sz < sizeof(*out))
	return -EINVAL;

	in = (struct scmi_rd_reset_in *)msg->in_msg;
	out = (struct scmi_rd_reset_out *)msg->out_msg;

	reset_state = get_scmi_reset_state(agent->idx, in->domain_id);
	if (!reset_state) {
	dev_err(dev, "Unexpected reset domain ID %u\n", in->domain_id);

	out->status = SCMI_NOT_FOUND;
	} else if (in->reset_state > 1) {
	dev_err(dev, "Invalid reset domain input attribute value\n");

	out->status = SCMI_INVALID_PARAMETERS;
	} else {
	if (in->flags & SCMI_RD_RESET_FLAG_CYCLE) {
	if (in->flags & SCMI_RD_RESET_FLAG_ASYNC) {
	out->status = SCMI_NOT_SUPPORTED;
	} else {
	/* Ends deasserted whatever current state */
	reset_state->asserted = false;
	out->status = SCMI_SUCCESS;
	}
	} else {
	reset_state->asserted = in->flags &
	SCMI_RD_RESET_FLAG_ASSERT;

	out->status = SCMI_SUCCESS;
	}
	}

	return 0;
	}

	static int sandbox_scmi_test_process_msg(struct udevice *dev,
	struct scmi_msg *msg)
	{
	switch (msg->protocol_id) {
	case SCMI_PROTOCOL_ID_CLOCK:
	switch (msg->message_id) {
	case SCMI_CLOCK_RATE_SET:
	return sandbox_scmi_clock_rate_set(dev, msg);
	case SCMI_CLOCK_RATE_GET:
	return sandbox_scmi_clock_rate_get(dev, msg);
	case SCMI_CLOCK_CONFIG_SET:
	return sandbox_scmi_clock_gate(dev, msg);
	default:
	break;
	}
	break;
	case SCMI_PROTOCOL_ID_RESET_DOMAIN:
	switch (msg->message_id) {
	case SCMI_RESET_DOMAIN_ATTRIBUTES:
	return sandbox_scmi_rd_attribs(dev, msg);
	case SCMI_RESET_DOMAIN_RESET:
	return sandbox_scmi_rd_reset(dev, msg);
	default:
	break;
	}
	break;
	case SCMI_PROTOCOL_ID_BASE:
	case SCMI_PROTOCOL_ID_POWER_DOMAIN:
	case SCMI_PROTOCOL_ID_SYSTEM:
	case SCMI_PROTOCOL_ID_PERF:
	case SCMI_PROTOCOL_ID_SENSOR:
	(u32 )msg->out_msg = SCMI_NOT_SUPPORTED;
	return 0;
	default:
	break;
	}

	dev_err(dev, "%s(%s): Unhandled protocol_id %#x/message_id %#x\n",
	__func__, dev->name, msg->protocol_id, msg->message_id);

	if (msg->out_msg_sz < sizeof(u32))
	return -EINVAL;

	/* Intentionnaly report unhandled IDs through the SCMI return code */
	(u32 )msg->out_msg = SCMI_PROTOCOL_ERROR;
	return 0;
	}

	static int sandbox_scmi_test_remove(struct udevice *dev)
	{
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);

	debug_print_agent_state(dev, "removed");

	/* We only need to dereference the agent in the context */
	sandbox_scmi_service_ctx()->agent[agent->idx] = NULL;

	return 0;
	}

	static int sandbox_scmi_test_probe(struct udevice *dev)
	{
	static const char basename[] = "sandbox-scmi-agent@";
	struct sandbox_scmi_agent *agent = dev_get_priv(dev);
	const size_t basename_size = sizeof(basename) - 1;

	if (strncmp(basename, dev->name, basename_size))
	return -ENOENT;

	switch (dev->name[basename_size]) {
	case '0':
	*agent = (struct sandbox_scmi_agent){
	.idx = 0,
	.clk = scmi0_clk,
	.clk_count = ARRAY_SIZE(scmi0_clk),
	.reset = scmi0_reset,
	.reset_count = ARRAY_SIZE(scmi0_reset),
	};
	break;
	case '1':
	*agent = (struct sandbox_scmi_agent){
	.idx = 1,
	.clk = scmi1_clk,
	.clk_count = ARRAY_SIZE(scmi1_clk),
	};
	break;
	default:
	dev_err(dev, "%s(): Unexpected agent ID %s\n",
	__func__, dev->name + basename_size);
	return -ENOENT;
	}

	debug_print_agent_state(dev, "probed");

	/* Save reference for tests purpose */
	sandbox_scmi_service_ctx()->agent[agent->idx] = agent;

	return 0;
	};

	static const struct udevice_id sandbox_scmi_test_ids[] = {
	{ .compatible = "sandbox,scmi-agent" },
	{ }
	};

	struct scmi_agent_ops sandbox_scmi_test_ops = {
	.process_msg = sandbox_scmi_test_process_msg,
	};

	U_BOOT_DRIVER(sandbox_scmi_agent) = {
	.name = "sandbox-scmi_agent",
	.id = UCLASS_SCMI_AGENT,
	.of_match = sandbox_scmi_test_ids,
	.priv_auto = sizeof(struct sandbox_scmi_agent),
	.probe = sandbox_scmi_test_probe,
	.remove = sandbox_scmi_test_remove,
	.ops = &sandbox_scmi_test_ops,
	};