linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (c) 2015-2018, Intel Corporation.

 */

​

#define pr_fmt(fmt) "kcs-bmc: " fmt

​

#include <linux/errno.h>

#include <linux/io.h>

#include <linux/ipmi_bmc.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/poll.h>

#include <linux/sched.h>

#include <linux/slab.h>

​

#include "kcs_bmc.h"

​

#define DEVICE_NAME "ipmi-kcs"

​

#define KCS_MSG_BUFSIZ    1000

​

#define KCS_ZERO_DATA     0

​

​

/* IPMI 2.0 - Table 9-1, KCS Interface Status Register Bits */

#define KCS_STATUS_STATE(state) (state << 6)

#define KCS_STATUS_STATE_MASK   GENMASK(7, 6)

#define KCS_STATUS_CMD_DAT      BIT(3)

#define KCS_STATUS_SMS_ATN      BIT(2)

#define KCS_STATUS_IBF          BIT(1)

#define KCS_STATUS_OBF          BIT(0)

​

/* IPMI 2.0 - Table 9-2, KCS Interface State Bits */

enum kcs_states {

    IDLE_STATE  = 0,

    READ_STATE  = 1,

    WRITE_STATE = 2,

    ERROR_STATE = 3,

};

​

/* IPMI 2.0 - Table 9-3, KCS Interface Control Codes */

#define KCS_CMD_GET_STATUS_ABORT  0x60

#define KCS_CMD_WRITE_START       0x61

#define KCS_CMD_WRITE_END         0x62

#define KCS_CMD_READ_BYTE         0x68

​

static inline u8 read_data(struct kcs_bmc *kcs_bmc)

{

    return kcs_bmc->io_inputb(kcs_bmc, kcs_bmc->ioreg.idr);

}

​

static inline void write_data(struct kcs_bmc *kcs_bmc, u8 data)

{

    kcs_bmc->io_outputb(kcs_bmc, kcs_bmc->ioreg.odr, data);

}

​

static inline u8 read_status(struct kcs_bmc *kcs_bmc)

{

    return kcs_bmc->io_inputb(kcs_bmc, kcs_bmc->ioreg.str);

}

​

static inline void write_status(struct kcs_bmc *kcs_bmc, u8 data)

{

    kcs_bmc->io_outputb(kcs_bmc, kcs_bmc->ioreg.str, data);

}

​

static void update_status_bits(struct kcs_bmc *kcs_bmc, u8 mask, u8 val)

{

    u8 tmp = read_status(kcs_bmc);

​

    tmp &= ~mask;

    tmp |= val & mask;

​

    write_status(kcs_bmc, tmp);

}

​

static inline void set_state(struct kcs_bmc *kcs_bmc, u8 state)

{

    update_status_bits(kcs_bmc, KCS_STATUS_STATE_MASK,

                    KCS_STATUS_STATE(state));

}

​

static void kcs_force_abort(struct kcs_bmc *kcs_bmc)

{

    set_state(kcs_bmc, ERROR_STATE);

    read_data(kcs_bmc);

    write_data(kcs_bmc, KCS_ZERO_DATA);

​

    kcs_bmc->phase = KCS_PHASE_ERROR;

    kcs_bmc->data_in_avail = false;

    kcs_bmc->data_in_idx = 0;