// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2009 - 2018 Intel Corporation. */
#include "mbx.h"
/**
* e1000_poll_for_msg - Wait for message notification
* @hw: pointer to the HW structure
*
* returns SUCCESS if it successfully received a message notification
**/
static s32 e1000_poll_for_msg(struct e1000_hw *hw)
{
struct e1000_mbx_info *mbx = &hw->mbx;
int countdown = mbx->timeout;
if (!mbx->ops.check_for_msg)
goto out;
while (countdown && mbx->ops.check_for_msg(hw)) {
countdown--;
udelay(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 acknowledgment
* @hw: pointer to the HW structure
*
* returns SUCCESS if it successfully received a message acknowledgment
**/
static s32 e1000_poll_for_ack(struct e1000_hw *hw)
{
struct e1000_mbx_info *mbx = &hw->mbx;
int countdown = mbx->timeout;
if (!mbx->ops.check_for_ack)
goto out;
while (countdown && mbx->ops.check_for_ack(hw)) {
countdown--;
udelay(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
*
* returns SUCCESS if it successfully received a message notification and
* copied it into the receive buffer.
**/
static s32 e1000_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size)
{
struct e1000_mbx_info *mbx = &hw->mbx;
s32 ret_val = -E1000_ERR_MBX;
if (!mbx->ops.read)
goto out;
ret_val = e1000_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;
}
/**
* 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
*
* returns SUCCESS if it successfully copied message into the buffer and
* received an ack to that message within delay * timeout period
**/
static s32 e1000_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size)
{
struct e1000_mbx_info *mbx = &hw->mbx;
s32 ret_val = -E1000_ERR_MBX;
/* exit if we either 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 = e1000_poll_for_ack(hw);
out:
return ret_val;
}
/**
* 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 = er32(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
*
* 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)
{
s32 ret_val = -E1000_ERR_MBX;
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
*
* 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)
{
s32 ret_val = -E1000_ERR_MBX;
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
*
* 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)
{
s32 ret_val = -E1000_ERR_MBX;
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;
do {
/* Take ownership of the buffer */
ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_VFU);
/* reserve mailbox for VF use */
if (e1000_read_v2p_mailbox(hw) & E1000_V2PMAILBOX_VFU) {
ret_val = 0;
break;
}
udelay(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
*
* returns SUCCESS if it successfully copied message into the buffer
**/
static s32 e1000_write_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size)
{
s32 err;
u16 i;
lockdep_assert_held(&hw->mbx_lock);
/* lock the mailbox to prevent pf/vf race condition */
err = e1000_obtain_mbx_lock_vf(hw);
if (err)
goto out_no_write;
/* flush any ack or msg as we are going to overwrite mailbox */
e1000_check_for_ack_vf(hw);
e1000_check_for_msg_vf(hw);
/* copy the caller specified message to the mailbox memory buffer */
for (i = 0; i < size; i++)
array_ew32(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 */
ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_REQ);
out_no_write:
return err;
}
/**
* 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
*
* returns SUCCESS if it successfully read message from buffer
**/
static s32 e1000_read_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size)
{
s32 err;
u16 i;
lockdep_assert_held(&hw->mbx_lock);
/* lock the mailbox to prevent pf/vf race condition */
err = e1000_obtain_mbx_lock_vf(hw);
if (err)
goto out_no_read;
/* copy the message from the mailbox memory buffer */
for (i = 0; i < size; i++)
msg[i] = array_er32(VMBMEM(0), i);
/* Acknowledge receipt and release mailbox, then we're done */
ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_ACK);
/* update stats */
hw->mbx.stats.msgs_rx++;
out_no_read:
return err;
}
/**
* 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 being 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;
}