syscons - Fix NULL pointer access in 0d7c8a4d1cafae68239

[dragonfly.git] / sys / dev / netif / ix / ixgbe_mbx.c

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

  Copyright (c) 2001-2017, Intel Corporation
  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,
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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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  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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******************************************************************************/
/*$FreeBSD$*/

#include "ixgbe_type.h"
#include "ixgbe_mbx.h"

/**
 *  ixgbe_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 successfuly read message from buffer
 **/
s32 ixgbe_read_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_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;
}

/**
 *  ixgbe_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 ixgbe_write_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_SUCCESS;

        DEBUGFUNC("ixgbe_write_mbx");

        if (size > mbx->size) {
                ret_val = IXGBE_ERR_MBX;
                ERROR_REPORT2(IXGBE_ERROR_ARGUMENT,
                             "Invalid mailbox message size %d", size);
        } else if (mbx->ops.write)
                ret_val = mbx->ops.write(hw, msg, size, mbx_id);

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_check_for_msg");

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

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_check_for_ack");

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

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_rst(struct ixgbe_hw *hw, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_check_for_rst");

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

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_poll_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;

        DEBUGFUNC("ixgbe_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 (countdown == 0)
                ERROR_REPORT2(IXGBE_ERROR_POLLING,
                           "Polling for VF%d mailbox message timedout", mbx_id);

out:
        return countdown ? IXGBE_SUCCESS : IXGBE_ERR_MBX;
}

/**
 *  ixgbe_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 ixgbe_poll_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;

        DEBUGFUNC("ixgbe_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 (countdown == 0)
                ERROR_REPORT2(IXGBE_ERROR_POLLING,
                             "Polling for VF%d mailbox ack timedout", mbx_id);

out:
        return countdown ? IXGBE_SUCCESS : IXGBE_ERR_MBX;
}

/**
 *  ixgbe_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 ixgbe_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_read_posted_mbx");

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

        ret_val = ixgbe_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;
}

/**
 *  ixgbe_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 ixgbe_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
                           u16 mbx_id)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_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 = ixgbe_poll_for_ack(hw, mbx_id);
out:
        return ret_val;
}

/**
 *  ixgbe_init_mbx_ops_generic - Initialize MB function pointers
 *  @hw: pointer to the HW structure
 *
 *  Setups up the mailbox read and write message function pointers
 **/
void ixgbe_init_mbx_ops_generic(struct ixgbe_hw *hw)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;

        mbx->ops.read_posted = ixgbe_read_posted_mbx;
        mbx->ops.write_posted = ixgbe_write_posted_mbx;
}

/**
 *  ixgbe_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 ixgbe_read_v2p_mailbox(struct ixgbe_hw *hw)
{
        u32 v2p_mailbox = IXGBE_READ_REG(hw, IXGBE_VFMAILBOX);

        v2p_mailbox |= hw->mbx.v2p_mailbox;
        hw->mbx.v2p_mailbox |= v2p_mailbox & IXGBE_VFMAILBOX_R2C_BITS;

        return v2p_mailbox;
}

/**
 *  ixgbe_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 ixgbe_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
{
        u32 v2p_mailbox = ixgbe_read_v2p_mailbox(hw);
        s32 ret_val = IXGBE_ERR_MBX;

        if (v2p_mailbox & mask)
                ret_val = IXGBE_SUCCESS;

        hw->mbx.v2p_mailbox &= ~mask;

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_msg_vf(struct ixgbe_hw *hw, u16 mbx_id)
{
        s32 ret_val = IXGBE_ERR_MBX;

        UNREFERENCED_1PARAMETER(mbx_id);
        DEBUGFUNC("ixgbe_check_for_msg_vf");

        if (!ixgbe_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
                ret_val = IXGBE_SUCCESS;
                hw->mbx.stats.reqs++;
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_ack_vf(struct ixgbe_hw *hw, u16 mbx_id)
{
        s32 ret_val = IXGBE_ERR_MBX;

        UNREFERENCED_1PARAMETER(mbx_id);
        DEBUGFUNC("ixgbe_check_for_ack_vf");

        if (!ixgbe_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
                ret_val = IXGBE_SUCCESS;
                hw->mbx.stats.acks++;
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_rst_vf(struct ixgbe_hw *hw, u16 mbx_id)
{
        s32 ret_val = IXGBE_ERR_MBX;

        UNREFERENCED_1PARAMETER(mbx_id);
        DEBUGFUNC("ixgbe_check_for_rst_vf");

        if (!ixgbe_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
            IXGBE_VFMAILBOX_RSTI))) {
                ret_val = IXGBE_SUCCESS;
                hw->mbx.stats.rsts++;
        }

        return ret_val;
}

/**
 *  ixgbe_obtain_mbx_lock_vf - obtain mailbox lock
 *  @hw: pointer to the HW structure
 *
 *  return SUCCESS if we obtained the mailbox lock
 **/
static s32 ixgbe_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
{
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_obtain_mbx_lock_vf");

        /* Take ownership of the buffer */
        IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);

        /* reserve mailbox for vf use */
        if (ixgbe_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
                ret_val = IXGBE_SUCCESS;

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size,
                              u16 mbx_id)
{
        s32 ret_val;
        u16 i;

        UNREFERENCED_1PARAMETER(mbx_id);

        DEBUGFUNC("ixgbe_write_mbx_vf");

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

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

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

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

        /* Drop VFU and interrupt the PF to tell it a message has been sent */
        IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_REQ);

out_no_write:
        return ret_val;
}

/**
 *  ixgbe_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 successfuly read message from buffer
 **/
static s32 ixgbe_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size,
                             u16 mbx_id)
{
        s32 ret_val = IXGBE_SUCCESS;
        u16 i;

        DEBUGFUNC("ixgbe_read_mbx_vf");
        UNREFERENCED_1PARAMETER(mbx_id);

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = ixgbe_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] = IXGBE_READ_REG_ARRAY(hw, IXGBE_VFMBMEM, i);

        /* Acknowledge receipt and release mailbox, then we're done */
        IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_ACK);

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

out_no_read:
        return ret_val;
}

/**
 *  ixgbe_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
 */
void ixgbe_init_mbx_params_vf(struct ixgbe_hw *hw)
{
        struct ixgbe_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 = IXGBE_VF_MBX_INIT_DELAY;

        mbx->size = IXGBE_VFMAILBOX_SIZE;

        mbx->ops.read = ixgbe_read_mbx_vf;
        mbx->ops.write = ixgbe_write_mbx_vf;
        mbx->ops.read_posted = ixgbe_read_posted_mbx;
        mbx->ops.write_posted = ixgbe_write_posted_mbx;
        mbx->ops.check_for_msg = ixgbe_check_for_msg_vf;
        mbx->ops.check_for_ack = ixgbe_check_for_ack_vf;
        mbx->ops.check_for_rst = ixgbe_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;
}

static s32 ixgbe_check_for_bit_pf(struct ixgbe_hw *hw, u32 mask, s32 index)
{
        u32 mbvficr = IXGBE_READ_REG(hw, IXGBE_MBVFICR(index));
        s32 ret_val = IXGBE_ERR_MBX;

        if (mbvficr & mask) {
                ret_val = IXGBE_SUCCESS;
                IXGBE_WRITE_REG(hw, IXGBE_MBVFICR(index), mask);
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_msg_pf(struct ixgbe_hw *hw, u16 vf_number)
{
        s32 ret_val = IXGBE_ERR_MBX;
        s32 index = IXGBE_MBVFICR_INDEX(vf_number);
        u32 vf_bit = vf_number % 16;

        DEBUGFUNC("ixgbe_check_for_msg_pf");

        if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFREQ_VF1 << vf_bit,
                                    index)) {
                ret_val = IXGBE_SUCCESS;
                hw->mbx.stats.reqs++;
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_ack_pf(struct ixgbe_hw *hw, u16 vf_number)
{
        s32 ret_val = IXGBE_ERR_MBX;
        s32 index = IXGBE_MBVFICR_INDEX(vf_number);
        u32 vf_bit = vf_number % 16;

        DEBUGFUNC("ixgbe_check_for_ack_pf");

        if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFACK_VF1 << vf_bit,
                                    index)) {
                ret_val = IXGBE_SUCCESS;
                hw->mbx.stats.acks++;
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_check_for_rst_pf(struct ixgbe_hw *hw, u16 vf_number)
{
        u32 reg_offset = (vf_number < 32) ? 0 : 1;
        u32 vf_shift = vf_number % 32;
        u32 vflre = 0;
        s32 ret_val = IXGBE_ERR_MBX;

        DEBUGFUNC("ixgbe_check_for_rst_pf");

        switch (hw->mac.type) {
        case ixgbe_mac_82599EB:
                vflre = IXGBE_READ_REG(hw, IXGBE_VFLRE(reg_offset));
                break;
        case ixgbe_mac_X550:
        case ixgbe_mac_X550EM_x:
        case ixgbe_mac_X550EM_a:
        case ixgbe_mac_X540:
                vflre = IXGBE_READ_REG(hw, IXGBE_VFLREC(reg_offset));
                break;
        default:
                break;
        }

        if (vflre & (1 << vf_shift)) {
                ret_val = IXGBE_SUCCESS;
                IXGBE_WRITE_REG(hw, IXGBE_VFLREC(reg_offset), (1 << vf_shift));
                hw->mbx.stats.rsts++;
        }

        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_obtain_mbx_lock_pf(struct ixgbe_hw *hw, u16 vf_number)
{
        s32 ret_val = IXGBE_ERR_MBX;
        u32 p2v_mailbox;

        DEBUGFUNC("ixgbe_obtain_mbx_lock_pf");

        /* Take ownership of the buffer */
        IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_PFU);

        /* reserve mailbox for vf use */
        p2v_mailbox = IXGBE_READ_REG(hw, IXGBE_PFMAILBOX(vf_number));
        if (p2v_mailbox & IXGBE_PFMAILBOX_PFU)
                ret_val = IXGBE_SUCCESS;
        else
                ERROR_REPORT2(IXGBE_ERROR_POLLING,
                           "Failed to obtain mailbox lock for VF%d", vf_number);


        return ret_val;
}

/**
 *  ixgbe_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 ixgbe_write_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
                              u16 vf_number)
{
        s32 ret_val;
        u16 i;

        DEBUGFUNC("ixgbe_write_mbx_pf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = ixgbe_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 */
        ixgbe_check_for_msg_pf(hw, vf_number);
        ixgbe_check_for_ack_pf(hw, vf_number);

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

        /* Interrupt VF to tell it a message has been sent and release buffer*/
        IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_STS);

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

out_no_write:
        return ret_val;

}

/**
 *  ixgbe_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 ixgbe_read_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
                             u16 vf_number)
{
        s32 ret_val;
        u16 i;

        DEBUGFUNC("ixgbe_read_mbx_pf");

        /* lock the mailbox to prevent pf/vf race condition */
        ret_val = ixgbe_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] = IXGBE_READ_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i);

        /* Acknowledge the message and release buffer */
        IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_ACK);

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

out_no_read:
        return ret_val;
}

/**
 *  ixgbe_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
 */
void ixgbe_init_mbx_params_pf(struct ixgbe_hw *hw)
{
        struct ixgbe_mbx_info *mbx = &hw->mbx;

        if (hw->mac.type != ixgbe_mac_82599EB &&
            hw->mac.type != ixgbe_mac_X550 &&
            hw->mac.type != ixgbe_mac_X550EM_x &&
            hw->mac.type != ixgbe_mac_X550EM_a &&
            hw->mac.type != ixgbe_mac_X540)
                return;

        mbx->timeout = 0;
        mbx->usec_delay = 0;

        mbx->size = IXGBE_VFMAILBOX_SIZE;

        mbx->ops.read = ixgbe_read_mbx_pf;
        mbx->ops.write = ixgbe_write_mbx_pf;
        mbx->ops.read_posted = ixgbe_read_posted_mbx;
        mbx->ops.write_posted = ixgbe_write_posted_mbx;
        mbx->ops.check_for_msg = ixgbe_check_for_msg_pf;
        mbx->ops.check_for_ack = ixgbe_check_for_ack_pf;
        mbx->ops.check_for_rst = ixgbe_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;
}