drivers/mdio/mdio_dwcxgmac.c

/*
 * Copyright (c) 2023 Intel Corporation.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#define DT_DRV_COMPAT snps_dwcxgmac_mdio

#include <errno.h>
#include <zephyr/kernel.h>
#include <zephyr/device.h>
#include <zephyr/drivers/mdio.h>
#include <zephyr/init.h>
#include <zephyr/logging/log.h>
#include <zephyr/drivers/reset.h>

LOG_MODULE_REGISTER(snps_dwcxgmac_mdio, CONFIG_MDIO_LOG_LEVEL);

#define XGMAC_DMA_BASE_ADDR_OFFSET (0x3000u)
#define DMA_MODE_OFST              (0x0)
#define DMA_MODE_SWR_SET_MSK       (0x00000001)
#define DMA_MODE_SWR_SET(value)    ((value) & 0x00000001)

#define MDIO_READ_CMD  (3u)
#define MDIO_WRITE_CMD (1u)

#define CORE_MDIO_SINGLE_COMMAND_ADDRESS_OFST                  0x200
#define CORE_MDIO_SINGLE_COMMAND_ADDRESS_RA_SET(value)         (((value) << 0) & 0x0000ffff)
#define CORE_MDIO_SINGLE_COMMAND_ADDRESS_PA_SET(value)         (((value) << 16) & 0x001f0000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_OFST             0x204
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SBUSY_SET_MSK    BIT(22)
#define CORE_MDIO_CLAUSE_22_PORT_OFST                          0x220
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SDATA_SET(value) (((value) << 0) & 0x0000ffff)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CMD_SET(value)   (((value) << 16) & 0x00030000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SADDR_SET(value) (((value) << 18) & 0x00040000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CR_SET(value)    (((value) << 19) & 0x00380000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CRS_SET(value)   (((value) << 31) & 0x80000000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SBUSY_SET(value) (((value) << 22) & 0x00400000)
#define CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SDATA_GET(value) (((value) & 0x0000ffff) >> 0)

struct mdio_dwcxgmac_dev_data {
	DEVICE_MMIO_RAM;
	struct k_mutex mdio_transfer_lock;
};

struct mdio_dwcxgmac_dev_config {
	DEVICE_MMIO_ROM;
	uint32_t clk_range;
	bool clk_range_sel;
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(resets)
	/* XGMAC peripheral reset signal */
	const struct reset_dt_spec reset;
#endif
};

static inline int dwxgmac_software_reset(mem_addr_t ioaddr)
{
	uint32_t delay_us = CONFIG_MDIO_DWCXGMAC_STATUS_BUSY_CHECK_TIMEOUT;
	bool ret;
	/* software reset */
	mem_addr_t reg_addr = (mem_addr_t)(ioaddr + XGMAC_DMA_BASE_ADDR_OFFSET + DMA_MODE_OFST);

	sys_write32(DMA_MODE_SWR_SET(1u), reg_addr);

	ret = WAIT_FOR(!(sys_read32(reg_addr) & DMA_MODE_SWR_SET_MSK), delay_us, k_msleep(1));
	if (ret == false) {
		return -ETIMEDOUT;
	}

	return 0;
}

static inline int mdio_busy_wait(uint32_t reg_addr, uint32_t bit_msk)
{
	uint32_t delay_us = CONFIG_MDIO_DWCXGMAC_STATUS_BUSY_CHECK_TIMEOUT;
	bool ret;

	ret = WAIT_FOR(!(sys_read32(reg_addr) & bit_msk), delay_us, k_msleep(1));
	if (ret == false) {
		return -ETIMEDOUT;
	}

	return 0;
}

static int mdio_transfer(const struct device *dev, uint8_t prtad, uint8_t devad, uint8_t rw,
			 uint16_t data_in, uint16_t *data_out)
{
	const struct mdio_dwcxgmac_dev_config *const cfg =
		(struct mdio_dwcxgmac_dev_config *)dev->config;
	struct mdio_dwcxgmac_dev_data *const data = (struct mdio_dwcxgmac_dev_data *)dev->data;
	int retval;
	mem_addr_t ioaddr = 0;
	uint32_t reg_addr;
	uint32_t reg_data, mdio_addr, mdio_data = 0;

	ioaddr = (mem_addr_t)DEVICE_MMIO_GET(dev);
	retval = mdio_busy_wait((ioaddr + CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_OFST),
				CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SBUSY_SET_MSK);
	if (retval) {
		LOG_ERR("%s: MDIO device busy wait timedout", dev->name);
		return retval;
	}

	(void)k_mutex_lock(&data->mdio_transfer_lock, K_FOREVER);
	/* Set port as Clause 22 */
	reg_addr = ioaddr + CORE_MDIO_CLAUSE_22_PORT_OFST;
	reg_data = sys_read32(reg_addr);
	reg_data |= BIT(prtad);
	sys_write32(reg_data, reg_addr);

	reg_addr = ioaddr + CORE_MDIO_SINGLE_COMMAND_ADDRESS_OFST;
	mdio_addr = CORE_MDIO_SINGLE_COMMAND_ADDRESS_RA_SET(devad) |
		    CORE_MDIO_SINGLE_COMMAND_ADDRESS_PA_SET(prtad);
	sys_write32(mdio_addr, reg_addr);

	reg_addr = ioaddr + CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_OFST;
	mdio_data = CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SDATA_SET(data_in) |
		    CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CMD_SET(rw) |
		    CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SADDR_SET(1u) |
		    CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CR_SET(cfg->clk_range) |
		    CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_CRS_SET(cfg->clk_range_sel) |
		    CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SBUSY_SET(1u);

	sys_write32(mdio_data, reg_addr);

	retval = mdio_busy_wait(reg_addr, CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SBUSY_SET_MSK);

	if (retval) {
		LOG_ERR("%s: transfer timedout", dev->name);
	} else {
		if (data_out) {
			*data_out = CORE_MDIO_SINGLE_COMMAND_CONTROL_DATA_SDATA_GET(
				sys_read32(reg_addr));
		}
	}

	(void)k_mutex_unlock(&data->mdio_transfer_lock);

	return retval;
}

static int mdio_dwcxgmac_read(const struct device *dev, uint8_t prtad, uint8_t regad,
			      uint16_t *data)
{
	return mdio_transfer(dev, prtad, regad, MDIO_READ_CMD, 0, data);
}

static int mdio_dwcxgmac_write(const struct device *dev, uint8_t prtad, uint8_t regad,
			       uint16_t data)
{
	return mdio_transfer(dev, prtad, regad, MDIO_WRITE_CMD, data, NULL);
}

static void mdio_dwcxgmac_bus_enable(const struct device *dev)
{
	ARG_UNUSED(dev);
}

static void mdio_dwcxgmac_bus_disable(const struct device *dev)
{
	ARG_UNUSED(dev);
}

static int mdio_dwcxgmac_initialize(const struct device *dev)
{
	struct mdio_dwcxgmac_dev_data *const data = (struct mdio_dwcxgmac_dev_data *)dev->data;
	const struct mdio_dwcxgmac_dev_config *const cfg =
		(struct mdio_dwcxgmac_dev_config *)dev->config;
	mem_addr_t ioaddr;
	int ret = 0;

#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(resets)

	if (cfg->reset.dev != NULL) {
		if (!device_is_ready(cfg->reset.dev)) {
			LOG_ERR("%s, Reset device is not ready", dev->name);
			return -ENODEV;
		}
		ret = reset_line_toggle(cfg->reset.dev, cfg->reset.id);
		if (ret) {
			LOG_ERR("%s: Failed to reset peripheral", dev->name);
			return ret;
		}
	} else {
		LOG_ERR("%s, Reset device is not available", dev->name);
		return -ENODEV;
	}

#endif

	DEVICE_MMIO_MAP(dev, K_MEM_CACHE_NONE);
	ioaddr = (mem_addr_t)DEVICE_MMIO_GET(dev);

	ret = dwxgmac_software_reset(ioaddr);
	if (ret) {
		LOG_ERR("%s: XGMAC reset timeout", dev->name);
		return ret;
	}

	k_mutex_init(&data->mdio_transfer_lock);

	return 0;
}

static DEVICE_API(mdio, mdio_dwcxgmac_driver_api) = {
	.read = mdio_dwcxgmac_read,
	.write = mdio_dwcxgmac_write,
	.bus_enable = mdio_dwcxgmac_bus_enable,
	.bus_disable = mdio_dwcxgmac_bus_disable,
};

#define XGMAC_SNPS_DESIGNWARE_RESET_SPEC_INIT(n) .reset = RESET_DT_SPEC_INST_GET(n),

#define MDIO_DWCXGMAC_CONFIG(n)                                                                   \
	static const struct mdio_dwcxgmac_dev_config mdio_dwcxgmac_dev_config_##n = {              \
		DEVICE_MMIO_ROM_INIT(DT_DRV_INST(n)),                                              \
		.clk_range = DT_INST_PROP(n, csr_clock_indx),                                      \
		.clk_range_sel = DT_INST_PROP(n, clock_range_sel),                                 \
		IF_ENABLED(DT_INST_NODE_HAS_PROP(n, resets),                                       \
			   (XGMAC_SNPS_DESIGNWARE_RESET_SPEC_INIT(n)))};

#define MDIO_DWCXGMAC_DEVICE(n)                                                                    \
	MDIO_DWCXGMAC_CONFIG(n);                                                                   \
	static struct mdio_dwcxgmac_dev_data mdio_dwcxgmac_dev_data##n;                            \
	DEVICE_DT_INST_DEFINE(n, &mdio_dwcxgmac_initialize, NULL, &mdio_dwcxgmac_dev_data##n,      \
			      &mdio_dwcxgmac_dev_config_##n, POST_KERNEL,                          \
			      CONFIG_MDIO_INIT_PRIORITY, &mdio_dwcxgmac_driver_api);

DT_INST_FOREACH_STATUS_OKAY(MDIO_DWCXGMAC_DEVICE)