// SPDX-License-Identifier: GPL-2.0+
/*
   Copyright (c) 2016 Broadcom Corporation
   All Rights Reserved

    
*/

/*
 *  Created on: Aug 2016
 *      Author: yuval.raviv@broadcom.com
 */

/*
 * MDIO common functions
 */

#include "mdio_drv_common.h"
#if defined(DSL_DEVICES)
/* TODO_DSL: SF2 based is little endian, no need to byte swap, but need to figure out how to use access_macros.h instead */
#define WRITE_32(a, r)			( *(volatile uint32_t*)(a) = *(uint32_t*)&(r) )
#define READ_32(a, r)			( *(volatile uint32_t*)&(r) = *(volatile uint32_t*) (a) )
#else
#include "access_macros.h"
#endif

#define MDIO_BUSY_RETRY         2000
#define CHECK_MDIO_READY(x)     if (!is_mdio_ready(x)) {ret = MDIO_ERROR; goto Exit;}

typedef enum
{
    MDIO_CLAUSE_45 = 0,
    MDIO_CLAUSE_22 = 1,
} mdio_clause_t;

typedef enum
{
    MDIO22_WRITE = 1,
    MDIO22_READ = 2,
} mdio22_op_t;

typedef enum
{
    MDIO45_ADDRESS = 0,
    MDIO45_WRITE = 1,
    MDIO45_READINC = 2,
    MDIO45_READ = 3,
} mdio45_op_t;

#if defined(CONFIG_BCM963178) || defined(CONFIG_BCM947622)
#ifndef _BYTE_ORDER_LITTLE_ENDIAN_
#define _BYTE_ORDER_LITTLE_ENDIAN_
#endif
#endif

#ifdef _BYTE_ORDER_LITTLE_ENDIAN_
#pragma pack(push, 1)
typedef struct
{
    uint32_t data_addr:16;
    uint32_t reg_dev_addr:5;
    uint32_t phy_prt_addr:5;
    uint32_t op_code:2;
    uint32_t fail:1;
    uint32_t busy:1;
    uint32_t reserved:2;
} mdio_cmd_reg_t;
#pragma pack(pop)

#pragma pack(push, 1)
typedef struct
{
    uint32_t mdio_clause:1;
    uint32_t unused1:3;
    uint32_t mdio_clk_divider:8;
    uint32_t unused2:1;
    uint32_t free_run_clk_enable:1;
    uint32_t unused3:18;
} mdio_cfg_reg_t;
#pragma pack(pop)
#else
#pragma pack(push, 1)
typedef struct
{
    uint32_t reserved:2;
    uint32_t busy:1;
    uint32_t fail:1;
    uint32_t op_code:2;
    uint32_t phy_prt_addr:5;
    uint32_t reg_dev_addr:5;
    uint32_t data_addr:16;
} mdio_cmd_reg_t;
#pragma pack(pop)

#pragma pack(push, 1)
typedef struct
{
    uint32_t unused3:18;
    uint32_t free_run_clk_enable:1;
    uint32_t unused2:1;
    uint32_t mdio_clk_divider:8;
    uint32_t unused1:3;
    uint32_t mdio_clause:1;
} mdio_cfg_reg_t;
#pragma pack(pop)
#endif

static int32_t is_mdio_ready(uint32_t *p)
{
    uint32_t retry = MDIO_BUSY_RETRY;
    mdio_cmd_reg_t cmd;

    do {
        READ_32(p, cmd);
        if (!cmd.busy)
            break;
        udelay(10);
    } while (retry--);

    if (!retry)
    {
        printk("MDIO Error: mdio_is_ready() reached maximum retries of %d\n", MDIO_BUSY_RETRY);
        return 0;
    }

    if (cmd.fail)
    {
        printk("MDIO Error: MDIO got failure status on phy %d\n", cmd.phy_prt_addr);
        memset(&cmd, 0, sizeof(cmd));
        WRITE_32(p, cmd);
        return 0;
    }

    return 1;
}

static void mdio_cfg_clause_mode(uint32_t *p, mdio_clause_t mdio_clause)
{
    mdio_cfg_reg_t cfg;

    READ_32(p, cfg);
    cfg.free_run_clk_enable = 1;
#if defined(CONFIG_BCM96846) || defined(CONFIG_BCM96856) || defined(CONFIG_BCM96878)
    cfg.mdio_clk_divider = 12;
#endif
    cfg.mdio_clause = mdio_clause;
    WRITE_32(p, cfg);
}

int32_t mdio_cmd_read_22(uint32_t *p, uint32_t addr, uint32_t reg, uint16_t *val)
{
    int ret = MDIO_OK;
    mdio_cmd_reg_t cmd = {};

    mdio_cfg_clause_mode(p + 1, MDIO_CLAUSE_22);

    cmd.op_code = MDIO22_READ;
    cmd.phy_prt_addr = addr;
    cmd.reg_dev_addr = reg;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

    READ_32(p, cmd);
    *val = cmd.data_addr;

Exit:
    return ret;
}

int32_t mdio_cmd_write_22(uint32_t *p, uint32_t addr, uint32_t reg, uint16_t val)
{
    int ret = MDIO_OK;
    mdio_cmd_reg_t cmd = {};

    mdio_cfg_clause_mode(p + 1, MDIO_CLAUSE_22);

    cmd.op_code = MDIO22_WRITE;
    cmd.phy_prt_addr = addr;
    cmd.reg_dev_addr = reg;
    cmd.data_addr = val;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

Exit:
    return ret;
}

int32_t mdio_cmd_read_45(uint32_t *p, uint32_t addr, uint32_t dev, uint16_t reg, uint16_t *val)
{
    int ret = MDIO_OK;
    mdio_cmd_reg_t cmd = {};

    mdio_cfg_clause_mode(p + 1, MDIO_CLAUSE_45);

    cmd.op_code = MDIO45_ADDRESS;
    cmd.phy_prt_addr = addr;
    cmd.reg_dev_addr = dev;
    cmd.data_addr = reg;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

    cmd.op_code = MDIO45_READ;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

    READ_32(p, cmd);
    *val = cmd.data_addr;

Exit:
    return ret;
}

int32_t mdio_cmd_write_45(uint32_t *p, uint32_t addr, uint32_t dev, uint16_t reg, uint16_t val)
{
    int ret = MDIO_OK;
    mdio_cmd_reg_t cmd = {};

    mdio_cfg_clause_mode(p + 1, MDIO_CLAUSE_45);

    cmd.op_code = MDIO45_ADDRESS;
    cmd.phy_prt_addr = addr;
    cmd.reg_dev_addr = dev;
    cmd.data_addr = reg;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

    cmd.op_code = MDIO45_WRITE;
    cmd.data_addr = val;
    cmd.busy = 1;
    WRITE_32(p, cmd);

    CHECK_MDIO_READY(p);

Exit:
    return ret;
}