drivers/reset/reset_gd32.c

/*
 * Copyright (c) 2022 Teslabs Engineering S.L.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#define DT_DRV_COMPAT gd_gd32_rctl

#include <zephyr/arch/cpu.h>
#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/reset.h>

/** RCU offset (from id field) */
#define GD32_RESET_ID_OFFSET(id) (((id) >> 6U) & 0xFFU)
/** RCU configuration bit (from id field) */
#define GD32_RESET_ID_BIT(id)	 ((id) & 0x1FU)

struct reset_gd32_config {
	uint32_t base;
};

static int reset_gd32_status(const struct device *dev, uint32_t id,
			     uint8_t *status)
{
	const struct reset_gd32_config *config = dev->config;

	*status = !!sys_test_bit(config->base + GD32_RESET_ID_OFFSET(id),
				 GD32_RESET_ID_BIT(id));

	return 0;
}

static int reset_gd32_line_assert(const struct device *dev, uint32_t id)
{
	const struct reset_gd32_config *config = dev->config;

	sys_set_bit(config->base + GD32_RESET_ID_OFFSET(id),
		    GD32_RESET_ID_BIT(id));

	return 0;
}

static int reset_gd32_line_deassert(const struct device *dev, uint32_t id)
{
	const struct reset_gd32_config *config = dev->config;

	sys_clear_bit(config->base + GD32_RESET_ID_OFFSET(id),
		      GD32_RESET_ID_BIT(id));

	return 0;
}

static int reset_gd32_line_toggle(const struct device *dev, uint32_t id)
{
	(void)reset_gd32_line_assert(dev, id);
	(void)reset_gd32_line_deassert(dev, id);

	return 0;
}

static const struct reset_driver_api reset_gd32_driver_api = {
	.status = reset_gd32_status,
	.line_assert = reset_gd32_line_assert,
	.line_deassert = reset_gd32_line_deassert,
	.line_toggle = reset_gd32_line_toggle,
};

static const struct reset_gd32_config config = {
	.base = DT_REG_ADDR(DT_INST_PARENT(0)),
};

DEVICE_DT_INST_DEFINE(0, NULL, NULL, NULL, &config, PRE_KERNEL_1,
		      CONFIG_RESET_INIT_PRIORITY, &reset_gd32_driver_api);