// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 1999 - 2018 Intel Corporation. */
#include "mbx.h"
#include "ixgbevf.h"
/**
* ixgbevf_poll_for_msg - Wait for message notification
* @hw: pointer to the HW structure
*
* returns 0 if it successfully received a message notification
**/
static s32 ixgbevf_poll_for_msg(struct ixgbe_hw *hw)
{
struct ixgbe_mbx_info *mbx = &hw->mbx;
int countdown = mbx->timeout;
while (countdown && mbx->ops.check_for_msg(hw)) {
countdown--;
udelay(mbx->udelay);
}
/* if we failed, all future posted messages fail until reset */
if (!countdown)
mbx->timeout = 0;
return countdown ? 0 : IXGBE_ERR_MBX;
}
/**
* ixgbevf_poll_for_ack - Wait for message acknowledgment
* @hw: pointer to the HW structure
*
* returns 0 if it successfully received a message acknowledgment
**/
static s32 ixgbevf_poll_for_ack(struct ixgbe_hw *hw)
{
struct ixgbe_mbx_info *mbx = &hw->mbx;
int countdown = mbx->timeout;
while (countdown && mbx->ops.check_for_ack(hw)) {
countdown--;
udelay(mbx->udelay);
}
/* if we failed, all future posted messages fail until reset */
if (!countdown)
mbx->timeout = 0;
return countdown ? 0 : IXGBE_ERR_MBX;
}
/**
* ixgbevf_read_posted_mbx - Wait for message notification and receive message
* @hw: pointer to the HW structure
* @msg: The message buffer
* @size: Length of buffer
*
* returns 0 if it successfully received a message notification and
* copied it into the receive buffer.
**/
static s32 ixgbevf_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
{
struct ixgbe_mbx_info *mbx = &hw->mbx;
s32 ret_val = IXGBE_ERR_MBX;
if (!mbx->ops.read)
goto out;
ret_val = ixgbevf_poll_for_msg(hw);
/* if ack received read message, otherwise we timed out */
if (!ret_val)
ret_val = mbx->ops.read(hw, msg, size);
out:
return ret_val;
}
/**
* ixgbevf_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
*
* returns 0 if it successfully copied message into the buffer and
* received an ack to that message within delay * timeout period
**/
static s32 ixgbevf_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
{
struct ixgbe_mbx_info *mbx = &hw->mbx;
s32 ret_val = IXGBE_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);
/* if msg sent wait until we receive an ack */
if (!ret_val)
ret_val = ixgbevf_poll_for_ack(hw);
out:
return ret_val;
}
/**
* ixgbevf_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 ixgbevf_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;
}
/**
* ixgbevf_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 ixgbevf_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
{
u32 v2p_mailbox = ixgbevf_read_v2p_mailbox(hw);
s32 ret_val = IXGBE_ERR_MBX;
if (v2p_mailbox & mask)
ret_val = 0;
hw->mbx.v2p_mailbox &= ~mask;
return ret_val;
}
/**
* ixgbevf_check_for_msg_vf - checks to see if the PF has sent mail
* @hw: pointer to the HW structure
*
* returns 0 if the PF has set the Status bit or else ERR_MBX
**/
static s32 ixgbevf_check_for_msg_vf(struct ixgbe_hw *hw)
{
s32 ret_val = IXGBE_ERR_MBX;
if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
ret_val = 0;
hw->mbx.stats.reqs++;
}
return ret_val;
}
/**
* ixgbevf_check_for_ack_vf - checks to see if the PF has ACK'd
* @hw: pointer to the HW structure
*
* returns 0 if the PF has set the ACK bit or else ERR_MBX
**/
static s32 ixgbevf_check_for_ack_vf(struct ixgbe_hw *hw)
{
s32 ret_val = IXGBE_ERR_MBX;
if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
ret_val = 0;
hw->mbx.stats.acks++;
}
return ret_val;
}
/**
* ixgbevf_check_for_rst_vf - checks to see if the PF has reset
* @hw: pointer to the HW structure
*
* returns true if the PF has set the reset done bit or else false
**/
static s32 ixgbevf_check_for_rst_vf(struct ixgbe_hw *hw)
{
s32 ret_val = IXGBE_ERR_MBX;
if (!ixgbevf_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
IXGBE_VFMAILBOX_RSTI))) {
ret_val = 0;
hw->mbx.stats.rsts++;
}
return ret_val;
}
/**
* ixgbevf_obtain_mbx_lock_vf - obtain mailbox lock
* @hw: pointer to the HW structure
*
* return 0 if we obtained the mailbox lock
**/
static s32 ixgbevf_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
{
s32 ret_val = IXGBE_ERR_MBX;
/* Take ownership of the buffer */
IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);
/* reserve mailbox for VF use */
if (ixgbevf_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
ret_val = 0;
return ret_val;
}
/**
* ixgbevf_write_mbx_vf - Write a message to the mailbox
* @hw: pointer to the HW structure
* @msg: The message buffer
* @size: Length of buffer
*
* returns 0 if it successfully copied message into the buffer
**/
static s32 ixgbevf_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
{
s32 ret_val;
u16 i;
/* lock the mailbox to prevent PF/VF race condition */
ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
if (ret_val)
goto out_no_write;
/* flush msg and acks as we are overwriting the message buffer */
ixgbevf_check_for_msg_vf(hw);
ixgbevf_check_for_ack_vf(hw);
/* 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;
}
/**
* ixgbevf_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
*
* returns 0 if it successfully read message from buffer
**/
static s32 ixgbevf_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
{
s32 ret_val = 0;
u16 i;
/* lock the mailbox to prevent PF/VF race condition */
ret_val = ixgbevf_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;
}
/**
* ixgbevf_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
*/
static s32 ixgbevf_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->udelay = IXGBE_VF_MBX_INIT_DELAY;
mbx->size = IXGBE_VFMAILBOX_SIZE;
mbx->stats.msgs_tx = 0;
mbx->stats.msgs_rx = 0;
mbx->stats.reqs = 0;
mbx->stats.acks = 0;
mbx->stats.rsts = 0;
return 0;
}
const struct ixgbe_mbx_operations ixgbevf_mbx_ops = {
.init_params = ixgbevf_init_mbx_params_vf,
.read = ixgbevf_read_mbx_vf,
.write = ixgbevf_write_mbx_vf,
.read_posted = ixgbevf_read_posted_mbx,
.write_posted = ixgbevf_write_posted_mbx,
.check_for_msg = ixgbevf_check_for_msg_vf,
.check_for_ack = ixgbevf_check_for_ack_vf,
.check_for_rst = ixgbevf_check_for_rst_vf,
};
/* Mailbox operations when running on Hyper-V.
* On Hyper-V, PF/VF communication is not through the
* hardware mailbox; this communication is through
* a software mediated path.
* Most mail box operations are noop while running on
* Hyper-V.
*/
const struct ixgbe_mbx_operations ixgbevf_hv_mbx_ops = {
.init_params = ixgbevf_init_mbx_params_vf,
.check_for_rst = ixgbevf_check_for_rst_vf,
};
