drivers/net/ethernet/intel/igb/e1000_mbx.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright(c) 2007 - 2018 Intel Corporation. */

 #include "e1000_mbx.h"

 /**
  *  igb_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
  *  @unlock: skip locking or not
  *
  *  returns SUCCESS if it successfully read message from buffer
  **/
 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id,
 		 bool unlock)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = -E1000_ERR_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, unlock);

 	return ret_val;
 }

 /**
  *  igb_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 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = 0;

 	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;
 }

 /**
  *  igb_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 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = -E1000_ERR_MBX;

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

 	return ret_val;
 }

 /**
  *  igb_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 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = -E1000_ERR_MBX;

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

 	return ret_val;
 }

 /**
  *  igb_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 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = -E1000_ERR_MBX;

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

 	return ret_val;
 }

 /**
  *  igb_unlock_mbx - unlock the mailbox
  *  @hw: pointer to the HW structure
  *  @mbx_id: id of mailbox to check
  *
  *  returns SUCCESS if the mailbox was unlocked or else ERR_MBX
  **/
 s32 igb_unlock_mbx(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	s32 ret_val = -E1000_ERR_MBX;

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

 	return ret_val;
 }

 /**
  *  igb_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 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	int countdown = mbx->timeout;

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

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

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

 /**
  *  igb_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 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	int countdown = mbx->timeout;

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

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

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

 /**
  *  igb_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.
  **/
 static s32 igb_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;

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

 	ret_val = igb_poll_for_msg(hw, mbx_id);

 	if (!ret_val)
 		ret_val = mbx->ops.read(hw, msg, size, mbx_id, true);
 out:
 	return ret_val;
 }

 /**
  *  igb_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
  **/
 static s32 igb_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;

 	/* 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 = igb_poll_for_ack(hw, mbx_id);
 out:
 	return ret_val;
 }

 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
 {
 	u32 mbvficr = rd32(E1000_MBVFICR);
 	s32 ret_val = -E1000_ERR_MBX;

 	if (mbvficr & mask) {
 		ret_val = 0;
 		wr32(E1000_MBVFICR, mask);
 	}

 	return ret_val;
 }

 /**
  *  igb_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 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
 {
 	s32 ret_val = -E1000_ERR_MBX;

 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
 		ret_val = 0;
 		hw->mbx.stats.reqs++;
 	}

 	return ret_val;
 }

 /**
  *  igb_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 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
 {
 	s32 ret_val = -E1000_ERR_MBX;

 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
 		ret_val = 0;
 		hw->mbx.stats.acks++;
 	}

 	return ret_val;
 }

 /**
  *  igb_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 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 {
 	u32 vflre = rd32(E1000_VFLRE);
 	s32 ret_val = -E1000_ERR_MBX;

 	if (vflre & BIT(vf_number)) {
 		ret_val = 0;
 		wr32(E1000_VFLRE, BIT(vf_number));
 		hw->mbx.stats.rsts++;
 	}

 	return ret_val;
 }

 /**
  *  igb_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 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
 {
 	s32 ret_val = -E1000_ERR_MBX;
 	u32 p2v_mailbox;
 	int count = 10;

 	do {
 		/* Take ownership of the buffer */
 		wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);

 		/* reserve mailbox for vf use */
 		p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
 		if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
 			ret_val = 0;
 			break;
 		}
 		udelay(1000);
 	} while (count-- > 0);

 	return ret_val;
 }

 /**
  *  igb_release_mbx_lock_pf - release mailbox lock
  *  @hw: pointer to the HW structure
  *  @vf_number: the VF index
  *
  *  return SUCCESS if we released the mailbox lock
  **/
 static s32 igb_release_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
 {
 	u32 p2v_mailbox;

 	/* drop PF lock of mailbox, if set */
 	p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
 	if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
 		wr32(E1000_P2VMAILBOX(vf_number),
 		     p2v_mailbox & ~E1000_P2VMAILBOX_PFU);

 	return 0;
 }

 /**
  *  igb_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 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 			    u16 vf_number)
 {
 	s32 ret_val;
 	u16 i;

 	/* lock the mailbox to prevent pf/vf race condition */
 	ret_val = igb_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 */
 	igb_check_for_msg_pf(hw, vf_number);
 	igb_check_for_ack_pf(hw, vf_number);

 	/* copy the caller specified message to the mailbox memory buffer */
 	for (i = 0; i < size; i++)
 		array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);

 	/* Interrupt VF to tell it a message has been sent and release buffer*/
 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);

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

 out_no_write:
 	return ret_val;

 }

 /**
  *  igb_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
  *  @unlock: unlock the mailbox when done?
  *
  *  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 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 			   u16 vf_number, bool unlock)
 {
 	s32 ret_val;
 	u16 i;

 	/* lock the mailbox to prevent pf/vf race condition */
 	ret_val = igb_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] = array_rd32(E1000_VMBMEM(vf_number), i);

 	/* Acknowledge the message and release mailbox lock (or not) */
 	if (unlock)
 		wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
 	else
 		wr32(E1000_P2VMAILBOX(vf_number),
 		     E1000_P2VMAILBOX_ACK | E1000_P2VMAILBOX_PFU);

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

 out_no_read:
 	return ret_val;
 }

 /**
  *  igb_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 igb_init_mbx_params_pf(struct e1000_hw *hw)
 {
 	struct e1000_mbx_info *mbx = &hw->mbx;

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

 	mbx->size = E1000_VFMAILBOX_SIZE;

 	mbx->ops.read = igb_read_mbx_pf;
 	mbx->ops.write = igb_write_mbx_pf;
 	mbx->ops.read_posted = igb_read_posted_mbx;
 	mbx->ops.write_posted = igb_write_posted_mbx;
 	mbx->ops.check_for_msg = igb_check_for_msg_pf;
 	mbx->ops.check_for_ack = igb_check_for_ack_pf;
 	mbx->ops.check_for_rst = igb_check_for_rst_pf;
 	mbx->ops.unlock = igb_release_mbx_lock_pf;

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

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0
	/* Copyright(c) 2007 - 2018 Intel Corporation. */

	#include "e1000_mbx.h"

	/**
	* igb_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
	* @unlock: skip locking or not
	*
	* returns SUCCESS if it successfully read message from buffer
	**/
	s32 igb_read_mbx(struct e1000_hw hw, u32 msg, u16 size, u16 mbx_id,
	bool unlock)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = -E1000_ERR_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, unlock);

	return ret_val;
	}

	/**
	* igb_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 igb_write_mbx(struct e1000_hw hw, u32 msg, u16 size, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = 0;

	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;
	}

	/**
	* igb_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 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = -E1000_ERR_MBX;

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

	return ret_val;
	}

	/**
	* igb_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 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = -E1000_ERR_MBX;

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

	return ret_val;
	}

	/**
	* igb_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 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = -E1000_ERR_MBX;

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

	return ret_val;
	}

	/**
	* igb_unlock_mbx - unlock the mailbox
	* @hw: pointer to the HW structure
	* @mbx_id: id of mailbox to check
	*
	* returns SUCCESS if the mailbox was unlocked or else ERR_MBX
	**/
	s32 igb_unlock_mbx(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	s32 ret_val = -E1000_ERR_MBX;

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

	return ret_val;
	}

	/**
	* igb_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 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	int countdown = mbx->timeout;

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

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

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

	/**
	* igb_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 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;
	int countdown = mbx->timeout;

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

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

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

	/**
	* igb_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.
	**/
	static s32 igb_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;

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

	ret_val = igb_poll_for_msg(hw, mbx_id);

	if (!ret_val)
	ret_val = mbx->ops.read(hw, msg, size, mbx_id, true);
	out:
	return ret_val;
	}

	/**
	* igb_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
	**/
	static s32 igb_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;

	/* 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 = igb_poll_for_ack(hw, mbx_id);
	out:
	return ret_val;
	}

	static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
	{
	u32 mbvficr = rd32(E1000_MBVFICR);
	s32 ret_val = -E1000_ERR_MBX;

	if (mbvficr & mask) {
	ret_val = 0;
	wr32(E1000_MBVFICR, mask);
	}

	return ret_val;
	}

	/**
	* igb_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 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
	{
	s32 ret_val = -E1000_ERR_MBX;

	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
	ret_val = 0;
	hw->mbx.stats.reqs++;
	}

	return ret_val;
	}

	/**
	* igb_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 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
	{
	s32 ret_val = -E1000_ERR_MBX;

	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
	ret_val = 0;
	hw->mbx.stats.acks++;
	}

	return ret_val;
	}

	/**
	* igb_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 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
	{
	u32 vflre = rd32(E1000_VFLRE);
	s32 ret_val = -E1000_ERR_MBX;

	if (vflre & BIT(vf_number)) {
	ret_val = 0;
	wr32(E1000_VFLRE, BIT(vf_number));
	hw->mbx.stats.rsts++;
	}

	return ret_val;
	}

	/**
	* igb_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 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
	{
	s32 ret_val = -E1000_ERR_MBX;
	u32 p2v_mailbox;
	int count = 10;

	do {
	/* Take ownership of the buffer */
	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);

	/* reserve mailbox for vf use */
	p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
	if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
	ret_val = 0;
	break;
	}
	udelay(1000);
	} while (count-- > 0);

	return ret_val;
	}

	/**
	* igb_release_mbx_lock_pf - release mailbox lock
	* @hw: pointer to the HW structure
	* @vf_number: the VF index
	*
	* return SUCCESS if we released the mailbox lock
	**/
	static s32 igb_release_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
	{
	u32 p2v_mailbox;

	/* drop PF lock of mailbox, if set */
	p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
	if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
	wr32(E1000_P2VMAILBOX(vf_number),
	p2v_mailbox & ~E1000_P2VMAILBOX_PFU);

	return 0;
	}

	/**
	* igb_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 igb_write_mbx_pf(struct e1000_hw hw, u32 msg, u16 size,
	u16 vf_number)
	{
	s32 ret_val;
	u16 i;

	/* lock the mailbox to prevent pf/vf race condition */
	ret_val = igb_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 */
	igb_check_for_msg_pf(hw, vf_number);
	igb_check_for_ack_pf(hw, vf_number);

	/* copy the caller specified message to the mailbox memory buffer */
	for (i = 0; i < size; i++)
	array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);

	/* Interrupt VF to tell it a message has been sent and release buffer*/
	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);

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

	out_no_write:
	return ret_val;

	}

	/**
	* igb_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
	* @unlock: unlock the mailbox when done?
	*
	* 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 igb_read_mbx_pf(struct e1000_hw hw, u32 msg, u16 size,
	u16 vf_number, bool unlock)
	{
	s32 ret_val;
	u16 i;

	/* lock the mailbox to prevent pf/vf race condition */
	ret_val = igb_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] = array_rd32(E1000_VMBMEM(vf_number), i);

	/* Acknowledge the message and release mailbox lock (or not) */
	if (unlock)
	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
	else
	wr32(E1000_P2VMAILBOX(vf_number),
	E1000_P2VMAILBOX_ACK \| E1000_P2VMAILBOX_PFU);

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

	out_no_read:
	return ret_val;
	}

	/**
	* igb_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 igb_init_mbx_params_pf(struct e1000_hw *hw)
	{
	struct e1000_mbx_info *mbx = &hw->mbx;

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

	mbx->size = E1000_VFMAILBOX_SIZE;

	mbx->ops.read = igb_read_mbx_pf;
	mbx->ops.write = igb_write_mbx_pf;
	mbx->ops.read_posted = igb_read_posted_mbx;
	mbx->ops.write_posted = igb_write_posted_mbx;
	mbx->ops.check_for_msg = igb_check_for_msg_pf;
	mbx->ops.check_for_ack = igb_check_for_ack_pf;
	mbx->ops.check_for_rst = igb_check_for_rst_pf;
	mbx->ops.unlock = igb_release_mbx_lock_pf;

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

	return 0;
	}