/******************************************************************************

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  All rights reserved.
  
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  modification, are permitted provided that the following conditions are met:
  
   1. Redistributions of source code must retain the above copyright notice, 
      this list of conditions and the following disclaimer.
  
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      notice, this list of conditions and the following disclaimer in the 
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      contributors may be used to endorse or promote products derived from 
      this software without specific prior written permission.
  
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  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
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******************************************************************************/
/*$FreeBSD$*/

#include "e1000_mbx.h"

/**
 *  e1000_null_mbx_check_for_flag - No-op function, return 0
 *  @hw: pointer to the HW structure
 **/
static s32 e1000_null_mbx_check_for_flag(struct e1000_hw E1000_UNUSEDARG *hw,
                                         u16 E1000_UNUSEDARG mbx_id)
{
        DEBUGFUNC("e1000_null_mbx_check_flag");

        return E1000_SUCCESS;
}

/**
 *  e1000_null_mbx_transact - No-op function, return 0
 *  @hw: pointer to the HW structure
 **/
static s32 e1000_null_mbx_transact(struct e1000_hw E1000_UNUSEDARG *hw,
                                   u32 E1000_UNUSEDARG *msg,
                                   u16 E1000_UNUSEDARG size,
                                   u16 E1000_UNUSEDARG mbx_id)
{
        DEBUGFUNC("e1000_null_mbx_rw_msg");

        return E1000_SUCCESS;
}

/**
 *  e1000_read_mbx - Reads a message from the mailbox
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to read
 *
 *  returns SUCCESS if it successfully read message from buffer
 **/
s32 e1000_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_read_mbx");

        /* limit read to size of mailbox */
        if (size > mbx->size)
                size = mbx->size;

        if (mbx->ops.read)
                ret_val = mbx->ops.read(hw, msg, size, mbx_id);

        return ret_val;
}

/**
 *  e1000_write_mbx - Write a message to the mailbox
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully copied message into the buffer
 **/
s32 e1000_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = E1000_SUCCESS;

        DEBUGFUNC("e1000_write_mbx");

        if (size > mbx->size)
                ret_val = -E1000_ERR_MBX;

        else if (mbx->ops.write)
                ret_val = mbx->ops.write(hw, msg, size, mbx_id);

        return ret_val;
}

/**
 *  e1000_check_for_msg - checks to see if someone sent us mail
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns SUCCESS if the Status bit was found or else ERR_MBX
 **/
s32 e1000_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_msg");

        if (mbx->ops.check_for_msg)
                ret_val = mbx->ops.check_for_msg(hw, mbx_id);

        return ret_val;
}

/**
 *  e1000_check_for_ack - checks to see if someone sent us ACK
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns SUCCESS if the Status bit was found or else ERR_MBX
 **/
s32 e1000_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_ack");

        if (mbx->ops.check_for_ack)
                ret_val = mbx->ops.check_for_ack(hw, mbx_id);

        return ret_val;
}

/**
 *  e1000_check_for_rst - checks to see if other side has reset
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns SUCCESS if the Status bit was found or else ERR_MBX
 **/
s32 e1000_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_rst");

        if (mbx->ops.check_for_rst)
                ret_val = mbx->ops.check_for_rst(hw, mbx_id);

        return ret_val;
}

/**
 *  e1000_poll_for_msg - Wait for message notification
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully received a message notification
 **/
static s32 e1000_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;

        DEBUGFUNC("e1000_poll_for_msg");

        if (!countdown || !mbx->ops.check_for_msg)
                goto out;

        while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
                countdown--;
                if (!countdown)
                        break;
                usec_delay(mbx->usec_delay);
        }

        /* if we failed, all future posted messages fail until reset */
        if (!countdown)
                mbx->timeout = 0;
out:
        return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
}

/**
 *  e1000_poll_for_ack - Wait for message acknowledgement
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully received a message acknowledgement
 **/
static s32 e1000_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;

        DEBUGFUNC("e1000_poll_for_ack");

        if (!countdown || !mbx->ops.check_for_ack)
                goto out;

        while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
                countdown--;
                if (!countdown)
                        break;
                usec_delay(mbx->usec_delay);
        }

        /* if we failed, all future posted messages fail until reset */
        if (!countdown)
                mbx->timeout = 0;
out:
        return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
}

/**
 *  e1000_read_posted_mbx - Wait for message notification and receive message
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully received a message notification and
 *  copied it into the receive buffer.
 **/
s32 e1000_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_read_posted_mbx");

        if (!mbx->ops.read)
                goto out;

        ret_val = e1000_poll_for_msg(hw, mbx_id);

        /* if ack received read message, otherwise we timed out */
        if (!ret_val)
                ret_val = mbx->ops.read(hw, msg, size, mbx_id);
out:
        return ret_val;
}

/**
 *  e1000_write_posted_mbx - Write a message to the mailbox, wait for ack
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully copied message into the buffer and
 *  received an ack to that message within delay * timeout period
 **/
s32 e1000_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_write_posted_mbx");

        /* exit if either we can't write or there isn't a defined timeout */
        if (!mbx->ops.write || !mbx->timeout)
                goto out;

        /* send msg */
        ret_val = mbx->ops.write(hw, msg, size, mbx_id);

        /* if msg sent wait until we receive an ack */
        if (!ret_val)
                ret_val = e1000_poll_for_ack(hw, mbx_id);
out:
        return ret_val;
}

/**
 *  e1000_init_mbx_ops_generic - Initialize mbx function pointers
 *  @hw: pointer to the HW structure
 *
 *  Sets the function pointers to no-op functions
 **/
void e1000_init_mbx_ops_generic(struct e1000_hw *hw)
{
        struct e1000_mbx_info *mbx = &hw->mbx;
        mbx->ops.init_params = e1000_null_ops_generic;
        mbx->ops.read = e1000_null_mbx_transact;
        mbx->ops.write = e1000_null_mbx_transact;
        mbx->ops.check_for_msg = e1000_null_mbx_check_for_flag;
        mbx->ops.check_for_ack = e1000_null_mbx_check_for_flag;
        mbx->ops.check_for_rst = e1000_null_mbx_check_for_flag;
        mbx->ops.read_posted = e1000_read_posted_mbx;
        mbx->ops.write_posted = e1000_write_posted_mbx;
}

/**
 *  e1000_read_v2p_mailbox - read v2p mailbox
 *  @hw: pointer to the HW structure
 *
 *  This function is used to read the v2p mailbox without losing the read to
 *  clear status bits.
 **/
static u32 e1000_read_v2p_mailbox(struct e1000_hw *hw)
{
        u32 v2p_mailbox = E1000_READ_REG(hw, E1000_V2PMAILBOX(0));

        v2p_mailbox |= hw->dev_spec.vf.v2p_mailbox;
        hw->dev_spec.vf.v2p_mailbox |= v2p_mailbox & E1000_V2PMAILBOX_R2C_BITS;

        return v2p_mailbox;
}

/**
 *  e1000_check_for_bit_vf - Determine if a status bit was set
 *  @hw: pointer to the HW structure
 *  @mask: bitmask for bits to be tested and cleared
 *
 *  This function is used to check for the read to clear bits within
 *  the V2P mailbox.
 **/
static s32 e1000_check_for_bit_vf(struct e1000_hw *hw, u32 mask)
{
        u32 v2p_mailbox = e1000_read_v2p_mailbox(hw);
        s32 ret_val = -E1000_ERR_MBX;

        if (v2p_mailbox & mask)
                ret_val = E1000_SUCCESS;

        hw->dev_spec.vf.v2p_mailbox &= ~mask;

        return ret_val;
}

/**
 *  e1000_check_for_msg_vf - checks to see if the PF has sent mail
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns SUCCESS if the PF has set the Status bit or else ERR_MBX
 **/
static s32 e1000_check_for_msg_vf(struct e1000_hw *hw,
                                  u16 E1000_UNUSEDARG mbx_id)
{
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_msg_vf");

        if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFSTS)) {
                ret_val = E1000_SUCCESS;
                hw->mbx.stats.reqs++;
        }

        return ret_val;
}

/**
 *  e1000_check_for_ack_vf - checks to see if the PF has ACK'd
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns SUCCESS if the PF has set the ACK bit or else ERR_MBX
 **/
static s32 e1000_check_for_ack_vf(struct e1000_hw *hw,
                                  u16 E1000_UNUSEDARG mbx_id)
{
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_ack_vf");

        if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFACK)) {
                ret_val = E1000_SUCCESS;
                hw->mbx.stats.acks++;
        }

        return ret_val;
}

/**
 *  e1000_check_for_rst_vf - checks to see if the PF has reset
 *  @hw: pointer to the HW structure
 *  @mbx_id: id of mailbox to check
 *
 *  returns TRUE if the PF has set the reset done bit or else FALSE
 **/
static s32 e1000_check_for_rst_vf(struct e1000_hw *hw,
                                  u16 E1000_UNUSEDARG mbx_id)
{
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_rst_vf");

        if (!e1000_check_for_bit_vf(hw, (E1000_V2PMAILBOX_RSTD |
                                         E1000_V2PMAILBOX_RSTI))) {
                ret_val = E1000_SUCCESS;
                hw->mbx.stats.rsts++;
        }

        return ret_val;
}

/**
 *  e1000_obtain_mbx_lock_vf - obtain mailbox lock
 *  @hw: pointer to the HW structure
 *
 *  return SUCCESS if we obtained the mailbox lock
 **/
static s32 e1000_obtain_mbx_lock_vf(struct e1000_hw *hw)
{
        s32 ret_val = -E1000_ERR_MBX;
        int count = 10;

        DEBUGFUNC("e1000_obtain_mbx_lock_vf");

        do {
                /* Take ownership of the buffer */
                E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_VFU);

                /* reserve mailbox for vf use */
                if (e1000_read_v2p_mailbox(hw) & E1000_V2PMAILBOX_VFU) {
                        ret_val = E1000_SUCCESS;
                        break;
                }
                usec_delay(1000);
        } while (count-- > 0);

        return ret_val;
}

/**
 *  e1000_write_mbx_vf - Write a message to the mailbox
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to write
 *
 *  returns SUCCESS if it successfully copied message into the buffer
 **/
static s32 e1000_write_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
                              u16 E1000_UNUSEDARG mbx_id)
{
        s32 ret_val;
        u16 i;


        DEBUGFUNC("e1000_write_mbx_vf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = e1000_obtain_mbx_lock_vf(hw);
        if (ret_val)
                goto out_no_write;

        /* flush msg and acks as we are overwriting the message buffer */
        e1000_check_for_msg_vf(hw, 0);
        e1000_check_for_ack_vf(hw, 0);

        /* copy the caller specified message to the mailbox memory buffer */
        for (i = 0; i < size; i++)
                E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(0), i, msg[i]);

        /* update stats */
        hw->mbx.stats.msgs_tx++;

        /* Drop VFU and interrupt the PF to tell it a message has been sent */
        E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_REQ);

out_no_write:
        return ret_val;
}

/**
 *  e1000_read_mbx_vf - Reads a message from the inbox intended for vf
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @mbx_id: id of mailbox to read
 *
 *  returns SUCCESS if it successfully read message from buffer
 **/
static s32 e1000_read_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
                             u16 E1000_UNUSEDARG mbx_id)
{
        s32 ret_val = E1000_SUCCESS;
        u16 i;

        DEBUGFUNC("e1000_read_mbx_vf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = e1000_obtain_mbx_lock_vf(hw);
        if (ret_val)
                goto out_no_read;

        /* copy the message from the mailbox memory buffer */
        for (i = 0; i < size; i++)
                msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(0), i);

        /* Acknowledge receipt and release mailbox, then we're done */
        E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_ACK);

        /* update stats */
        hw->mbx.stats.msgs_rx++;

out_no_read:
        return ret_val;
}

/**
 *  e1000_init_mbx_params_vf - set initial values for vf mailbox
 *  @hw: pointer to the HW structure
 *
 *  Initializes the hw->mbx struct to correct values for vf mailbox
 */
s32 e1000_init_mbx_params_vf(struct e1000_hw *hw)
{
        struct e1000_mbx_info *mbx = &hw->mbx;

        /* start mailbox as timed out and let the reset_hw call set the timeout
         * value to begin communications */
        mbx->timeout = 0;
        mbx->usec_delay = E1000_VF_MBX_INIT_DELAY;

        mbx->size = E1000_VFMAILBOX_SIZE;

        mbx->ops.read = e1000_read_mbx_vf;
        mbx->ops.write = e1000_write_mbx_vf;
        mbx->ops.read_posted = e1000_read_posted_mbx;
        mbx->ops.write_posted = e1000_write_posted_mbx;
        mbx->ops.check_for_msg = e1000_check_for_msg_vf;
        mbx->ops.check_for_ack = e1000_check_for_ack_vf;
        mbx->ops.check_for_rst = e1000_check_for_rst_vf;

        mbx->stats.msgs_tx = 0;
        mbx->stats.msgs_rx = 0;
        mbx->stats.reqs = 0;
        mbx->stats.acks = 0;
        mbx->stats.rsts = 0;

        return E1000_SUCCESS;
}

static s32 e1000_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
{
        u32 mbvficr = E1000_READ_REG(hw, E1000_MBVFICR);
        s32 ret_val = -E1000_ERR_MBX;

        if (mbvficr & mask) {
                ret_val = E1000_SUCCESS;
                E1000_WRITE_REG(hw, E1000_MBVFICR, mask);
        }

        return ret_val;
}

/**
 *  e1000_check_for_msg_pf - checks to see if the VF has sent mail
 *  @hw: pointer to the HW structure
 *  @vf_number: the VF index
 *
 *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 **/
static s32 e1000_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
{
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_msg_pf");

        if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
                ret_val = E1000_SUCCESS;
                hw->mbx.stats.reqs++;
        }

        return ret_val;
}

/**
 *  e1000_check_for_ack_pf - checks to see if the VF has ACKed
 *  @hw: pointer to the HW structure
 *  @vf_number: the VF index
 *
 *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 **/
static s32 e1000_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
{
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_ack_pf");

        if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
                ret_val = E1000_SUCCESS;
                hw->mbx.stats.acks++;
        }

        return ret_val;
}

/**
 *  e1000_check_for_rst_pf - checks to see if the VF has reset
 *  @hw: pointer to the HW structure
 *  @vf_number: the VF index
 *
 *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 **/
static s32 e1000_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
{
        u32 vflre = E1000_READ_REG(hw, E1000_VFLRE);
        s32 ret_val = -E1000_ERR_MBX;

        DEBUGFUNC("e1000_check_for_rst_pf");

        if (vflre & (1 << vf_number)) {
                ret_val = E1000_SUCCESS;
                E1000_WRITE_REG(hw, E1000_VFLRE, (1 << vf_number));
                hw->mbx.stats.rsts++;
        }

        return ret_val;
}

/**
 *  e1000_obtain_mbx_lock_pf - obtain mailbox lock
 *  @hw: pointer to the HW structure
 *  @vf_number: the VF index
 *
 *  return SUCCESS if we obtained the mailbox lock
 **/
static s32 e1000_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
{
        s32 ret_val = -E1000_ERR_MBX;
        u32 p2v_mailbox;
        int count = 10;

        DEBUGFUNC("e1000_obtain_mbx_lock_pf");

        do {
                /* Take ownership of the buffer */
                E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number),
                                E1000_P2VMAILBOX_PFU);

                /* reserve mailbox for pf use */
                p2v_mailbox = E1000_READ_REG(hw, E1000_P2VMAILBOX(vf_number));
                if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
                        ret_val = E1000_SUCCESS;
                        break;
                }
                usec_delay(1000);
        } while (count-- > 0);

        return ret_val;

}

/**
 *  e1000_write_mbx_pf - Places a message in the mailbox
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @vf_number: the VF index
 *
 *  returns SUCCESS if it successfully copied message into the buffer
 **/
static s32 e1000_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
                              u16 vf_number)
{
        s32 ret_val;
        u16 i;

        DEBUGFUNC("e1000_write_mbx_pf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
        if (ret_val)
                goto out_no_write;

        /* flush msg and acks as we are overwriting the message buffer */
        e1000_check_for_msg_pf(hw, vf_number);
        e1000_check_for_ack_pf(hw, vf_number);

        /* copy the caller specified message to the mailbox memory buffer */
        for (i = 0; i < size; i++)
                E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i, msg[i]);

        /* Interrupt VF to tell it a message has been sent and release buffer*/
        E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);

        /* update stats */
        hw->mbx.stats.msgs_tx++;

out_no_write:
        return ret_val;

}

/**
 *  e1000_read_mbx_pf - Read a message from the mailbox
 *  @hw: pointer to the HW structure
 *  @msg: The message buffer
 *  @size: Length of buffer
 *  @vf_number: the VF index
 *
 *  This function copies a message from the mailbox buffer to the caller's
 *  memory buffer.  The presumption is that the caller knows that there was
 *  a message due to a VF request so no polling for message is needed.
 **/
static s32 e1000_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
                             u16 vf_number)
{
        s32 ret_val;
        u16 i;

        DEBUGFUNC("e1000_read_mbx_pf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
        if (ret_val)
                goto out_no_read;

        /* copy the message to the mailbox memory buffer */
        for (i = 0; i < size; i++)
                msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i);

        /* Acknowledge the message and release buffer */
        E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);

        /* update stats */
        hw->mbx.stats.msgs_rx++;

out_no_read:
        return ret_val;
}

/**
 *  e1000_init_mbx_params_pf - set initial values for pf mailbox
 *  @hw: pointer to the HW structure
 *
 *  Initializes the hw->mbx struct to correct values for pf mailbox
 */
s32 e1000_init_mbx_params_pf(struct e1000_hw *hw)
{
        struct e1000_mbx_info *mbx = &hw->mbx;

        switch (hw->mac.type) {
        case e1000_82576:
        case e1000_i350:
        case e1000_i354:
                mbx->timeout = 0;
                mbx->usec_delay = 0;

                mbx->size = E1000_VFMAILBOX_SIZE;

                mbx->ops.read = e1000_read_mbx_pf;
                mbx->ops.write = e1000_write_mbx_pf;
                mbx->ops.read_posted = e1000_read_posted_mbx;
                mbx->ops.write_posted = e1000_write_posted_mbx;
                mbx->ops.check_for_msg = e1000_check_for_msg_pf;
                mbx->ops.check_for_ack = e1000_check_for_ack_pf;
                mbx->ops.check_for_rst = e1000_check_for_rst_pf;

                mbx->stats.msgs_tx = 0;
                mbx->stats.msgs_rx = 0;
                mbx->stats.reqs = 0;
                mbx->stats.acks = 0;
                mbx->stats.rsts = 0;
                /* FALLTHROUGH */
        default:
                return E1000_SUCCESS;
        }
}