// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2013 - 2019 Intel Corporation. */
#include "fm10k_common.h"
/**
* fm10k_fifo_init - Initialize a message FIFO
* @fifo: pointer to FIFO
* @buffer: pointer to memory to be used to store FIFO
* @size: maximum message size to store in FIFO, must be 2^n - 1
**/
static void fm10k_fifo_init(struct fm10k_mbx_fifo *fifo, u32 *buffer, u16 size)
{
fifo->buffer = buffer;
fifo->size = size;
fifo->head = 0;
fifo->tail = 0;
}
/**
* fm10k_fifo_used - Retrieve used space in FIFO
* @fifo: pointer to FIFO
*
* This function returns the number of DWORDs used in the FIFO
**/
static u16 fm10k_fifo_used(struct fm10k_mbx_fifo *fifo)
{
return fifo->tail - fifo->head;
}
/**
* fm10k_fifo_unused - Retrieve unused space in FIFO
* @fifo: pointer to FIFO
*
* This function returns the number of unused DWORDs in the FIFO
**/
static u16 fm10k_fifo_unused(struct fm10k_mbx_fifo *fifo)
{
return fifo->size + fifo->head - fifo->tail;
}
/**
* fm10k_fifo_empty - Test to verify if FIFO is empty
* @fifo: pointer to FIFO
*
* This function returns true if the FIFO is empty, else false
**/
static bool fm10k_fifo_empty(struct fm10k_mbx_fifo *fifo)
{
return fifo->head == fifo->tail;
}
/**
* fm10k_fifo_head_offset - returns indices of head with given offset
* @fifo: pointer to FIFO
* @offset: offset to add to head
*
* This function returns the indices into the FIFO based on head + offset
**/
static u16 fm10k_fifo_head_offset(struct fm10k_mbx_fifo *fifo, u16 offset)
{
return (fifo->head + offset) & (fifo->size - 1);
}
/**
* fm10k_fifo_tail_offset - returns indices of tail with given offset
* @fifo: pointer to FIFO
* @offset: offset to add to tail
*
* This function returns the indices into the FIFO based on tail + offset
**/
static u16 fm10k_fifo_tail_offset(struct fm10k_mbx_fifo *fifo, u16 offset)
{
return (fifo->tail + offset) & (fifo->size - 1);
}
/**
* fm10k_fifo_head_len - Retrieve length of first message in FIFO
* @fifo: pointer to FIFO
*
* This function returns the size of the first message in the FIFO
**/
static u16 fm10k_fifo_head_len(struct fm10k_mbx_fifo *fifo)
{
u32 *head = fifo->buffer + fm10k_fifo_head_offset(fifo, 0);
/* verify there is at least 1 DWORD in the fifo so *head is valid */
if (fm10k_fifo_empty(fifo))
return 0;
/* retieve the message length */
return FM10K_TLV_DWORD_LEN(*head);
}
/**
* fm10k_fifo_head_drop - Drop the first message in FIFO
* @fifo: pointer to FIFO
*
* This function returns the size of the message dropped from the FIFO
**/
static u16 fm10k_fifo_head_drop(struct fm10k_mbx_fifo *fifo)
{
u16 len = fm10k_fifo_head_len(fifo);
/* update head so it is at the start of next frame */
fifo->head += len;
return len;
}
/**
* fm10k_fifo_drop_all - Drop all messages in FIFO
* @fifo: pointer to FIFO
*
* This function resets the head pointer to drop all messages in the FIFO and
* ensure the FIFO is empty.
**/
static void fm10k_fifo_drop_all(struct fm10k_mbx_fifo *fifo)
{
fifo->head = fifo->tail;
}
/**
* fm10k_mbx_index_len - Convert a head/tail index into a length value
* @mbx: pointer to mailbox
* @head: head index
* @tail: head index
*
* This function takes the head and tail index and determines the length
* of the data indicated by this pair.
**/
static u16 fm10k_mbx_index_len(struct fm10k_mbx_info *mbx, u16 head, u16 tail)
{
u16 len = tail - head;
/* we wrapped so subtract 2, one for index 0, one for all 1s index */
if (len > tail)
len -= 2;
return len & ((mbx->mbmem_len << 1) - 1);
}
/**
* fm10k_mbx_tail_add - Determine new tail value with added offset
* @mbx: pointer to mailbox
* @offset: length to add to tail offset
*
* This function takes the local tail index and recomputes it for
* a given length added as an offset.
**/
static u16 fm10k_mbx_tail_add(struct fm10k_mbx_info *mbx, u16 offset)
{
u16 tail = (mbx->tail + offset + 1) & ((mbx->mbmem_len << 1) - 1);
/* add/sub 1 because we cannot have offset 0 or all 1s */
return (tail > mbx->tail) ? --tail : ++tail;
}
/**
* fm10k_mbx_tail_sub - Determine new tail value with subtracted offset
* @mbx: pointer to mailbox
* @offset: length to add to tail offset
*
* This function takes the local tail index and recomputes it for
* a given length added as an offset.
**/
static u16 fm10k_mbx_tail_sub(struct fm10k_mbx_info *mbx, u16 offset)
{
u16 tail = (mbx->tail - offset - 1) & ((mbx->mbmem_len << 1) - 1);
/* sub/add 1 because we cannot have offset 0 or all 1s */
return (tail < mbx->tail) ? ++tail : --tail;
}
/**
* fm10k_mbx_head_add - Determine new head value with added offset
* @mbx: pointer to mailbox
* @offset: length to add to head offset
*
* This function takes the local head index and recomputes it for
* a given length added as an offset.
**/
static u16 fm10k_mbx_head_add(struct fm10k_mbx_info *mbx, u16 offset)
{
u16 head = (mbx->head + offset + 1) & ((mbx->mbmem_len << 1) - 1);
/* add/sub 1 because we cannot have offset 0 or all 1s */
return (head > mbx->head) ? --head : ++head;
}
/**
* fm10k_mbx_head_sub - Determine new head value with subtracted offset
* @mbx: pointer to mailbox
* @offset: length to add to head offset
*
* This function takes the local head index and recomputes it for
* a given length added as an offset.
**/
static u16 fm10k_mbx_head_sub(struct fm10k_mbx_info *mbx, u16 offset)
{
u16 head = (mbx->head - offset - 1) & ((mbx->mbmem_len << 1) - 1);
/* sub/add 1 because we cannot have offset 0 or all 1s */
return (head < mbx->head) ? ++head : --head;
}
/**
* fm10k_mbx_pushed_tail_len - Retrieve the length of message being pushed
* @mbx: pointer to mailbox
*
* This function will return the length of the message currently being
* pushed onto the tail of the Rx queue.
**/
static u16 fm10k_mbx_pushed_tail_len(struct fm10k_mbx_info *mbx)
{
u32 *tail = mbx->rx.buffer + fm10k_fifo_tail_offset(&mbx->rx, 0);
/* pushed tail is only valid if pushed is set */
if (!mbx->pushed)
return 0;
return FM10K_TLV_DWORD_LEN(*tail);
}
/**
* fm10k_fifo_write_copy - pulls data off of msg and places it in FIFO
* @fifo: pointer to FIFO
* @msg: message array to populate
* @tail_offset: additional offset to add to tail pointer
* @len: length of FIFO to copy into message header
*
* This function will take a message and copy it into a section of the
* FIFO. In order to get something into a location other than just
* the tail you can use tail_offset to adjust the pointer.
**/
static void fm10k_fifo_write_copy(struct fm10k_mbx_fifo *fifo,
const u32 *msg, u16 tail_offset, u16 len)
{
u16 end = fm10k_fifo_tail_offset(fifo, tail_offset);
u32 *tail = fifo->buffer + end;
/* track when we should cross the end of the FIFO */
end = fifo->size - end;
/* copy end of message before start of message */
if (end < len)
memcpy(fifo->buffer, msg + end, (len - end) << 2);
else
end = len;
/* Copy remaining message into Tx FIFO */
memcpy(tail, msg, end << 2);
}
/**
* fm10k_fifo_enqueue - Enqueues the message to the tail of the FIFO
* @fifo: pointer to FIFO
* @msg: message array to read
*
* This function enqueues a message up to the size specified by the length
* contained in the first DWORD of the message and will place at the tail
* of the FIFO. It will return 0 on success, or a negative value on error.
**/
static s32 fm10k_fifo_enqueue(struct fm10k_mbx_fifo *fifo, const u32 *msg)
{
u16 len = FM10K_TLV_DWORD_LEN(*msg);
/* verify parameters */
if (len > fifo->size)
return FM10K_MBX_ERR_SIZE;
/* verify there is room for the message */
if (len > fm10k_fifo_unused(fifo))
return FM10K_MBX_ERR_NO_SPACE;
/* Copy message into FIFO */
fm10k_fifo_write_copy(fifo, msg, 0, len);
/* memory barrier to guarantee FIFO is written before tail update */
wmb();
/* Update Tx FIFO tail */
fifo->tail += len;
return 0;
}
/**
* fm10k_mbx_validate_msg_size - Validate incoming message based on size
* @mbx: pointer to mailbox
* @len: length of data pushed onto buffer
*
* This function analyzes the frame and will return a non-zero value when
* the start of a message larger than the mailbox is detected.
**/
static u16 fm10k_mbx_validate_msg_size(struct fm10k_mbx_info *mbx, u16 len)
{
struct fm10k_mbx_fifo *fifo = &mbx->rx;
u16 total_len = 0, msg_len;
/* length should include previous amounts pushed */
len += mbx->pushed;
/* offset in message is based off of current message size */
do {
u32 *msg;
msg = fifo->buffer + fm10k_fifo_tail_offset(fifo, total_len);
msg_len = FM10K_TLV_DWORD_LEN(*msg);
total_len += msg_len;
} while (total_len < len);
/* message extends out of pushed section, but fits in FIFO */
if ((len < total_len) && (msg_len <= mbx->max_size))
return 0;
/* return length of invalid section */
return (len < total_len) ? len : (len - total_len);
}
/**
* fm10k_mbx_write_copy - pulls data off of Tx FIFO and places it in mbmem
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will take a section of the Tx FIFO and copy it into the
* mailbox memory. The offset in mbmem is based on the lower bits of the
* tail and len determines the length to copy.
**/
static void fm10k_mbx_write_copy(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
struct fm10k_mbx_fifo *fifo = &mbx->tx;
u32 mbmem = mbx->mbmem_reg;
u32 *head = fifo->buffer;
u16 end, len, tail, mask;
if (!mbx->tail_len)
return;
/* determine data length and mbmem tail index */
mask = mbx->mbmem_len - 1;
len = mbx->tail_len;
tail = fm10k_mbx_tail_sub(mbx, len);
if (tail > mask)
tail++;
/* determine offset in the ring */
end = fm10k_fifo_head_offset(fifo, mbx->pulled);
head += end;
/* memory barrier to guarantee data is ready to be read */
rmb();
/* Copy message from Tx FIFO */
for (end = fifo->size - end; len; head = fifo->buffer) {
do {
/* adjust tail to match offset for FIFO */
tail &= mask;
if (!tail)
tail++;
mbx->tx_mbmem_pulled++;
/* write message to hardware FIFO */
fm10k_write_reg(hw, mbmem + tail++, *(head++));
} while (--len && --end);
}
}
/**
* fm10k_mbx_pull_head - Pulls data off of head of Tx FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @head: acknowledgement number last received
*
* This function will push the tail index forward based on the remote
* head index. It will then pull up to mbmem_len DWORDs off of the
* head of the FIFO and will place it in the MBMEM registers
* associated with the mailbox.
**/
static void fm10k_mbx_pull_head(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx, u16 head)
{
u16 mbmem_len, len, ack = fm10k_mbx_index_len(mbx, head, mbx->tail);
struct fm10k_mbx_fifo *fifo = &mbx->tx;
/* update number of bytes pulled and update bytes in transit */
mbx->pulled += mbx->tail_len - ack;
/* determine length of data to pull, reserve space for mbmem header */
mbmem_len = mbx->mbmem_len - 1;
len = fm10k_fifo_used(fifo) - mbx->pulled;
if (len > mbmem_len)
len = mbmem_len;
/* update tail and record number of bytes in transit */
mbx->tail = fm10k_mbx_tail_add(mbx, len - ack);
mbx->tail_len = len;
/* drop pulled messages from the FIFO */
for (len = fm10k_fifo_head_len(fifo);
len && (mbx->pulled >= len);
len = fm10k_fifo_head_len(fifo)) {
mbx->pulled -= fm10k_fifo_head_drop(fifo);
mbx->tx_messages++;
mbx->tx_dwords += len;
}
/* Copy message out from the Tx FIFO */
fm10k_mbx_write_copy(hw, mbx);
}
/**
* fm10k_mbx_read_copy - pulls data off of mbmem and places it in Rx FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will take a section of the mailbox memory and copy it
* into the Rx FIFO. The offset is based on the lower bits of the
* head and len determines the length to copy.
**/
static void fm10k_mbx_read_copy(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
struct fm10k_mbx_fifo *fifo = &mbx->rx;
u32 mbmem = mbx->mbmem_reg ^ mbx->mbmem_len;
u32 *tail = fifo->buffer;
u16 end, len, head;
/* determine data length and mbmem head index */
len = mbx->head_len;
head = fm10k_mbx_head_sub(mbx, len);
if (head >= mbx->mbmem_len)
head++;
/* determine offset in the ring */
end = fm10k_fifo_tail_offset(fifo, mbx->pushed);
tail += end;
/* Copy message into Rx FIFO */
for (end = fifo->size - end; len; tail = fifo->buffer) {
do {
/* adjust head to match offset for FIFO */
head &= mbx->mbmem_len - 1;
if (!head)
head++;
mbx->rx_mbmem_pushed++;
/* read message from hardware FIFO */
*(tail++) = fm10k_read_reg(hw, mbmem + head++);
} while (--len && --end);
}
/* memory barrier to guarantee FIFO is written before tail update */
wmb();
}
/**
* fm10k_mbx_push_tail - Pushes up to 15 DWORDs on to tail of FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @tail: tail index of message
*
* This function will first validate the tail index and size for the
* incoming message. It then updates the acknowledgment number and
* copies the data into the FIFO. It will return the number of messages
* dequeued on success and a negative value on error.
**/
static s32 fm10k_mbx_push_tail(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx,
u16 tail)
{
struct fm10k_mbx_fifo *fifo = &mbx->rx;
u16 len, seq = fm10k_mbx_index_len(mbx, mbx->head, tail);
/* determine length of data to push */
len = fm10k_fifo_unused(fifo) - mbx->pushed;
if (len > seq)
len = seq;
/* update head and record bytes received */
mbx->head = fm10k_mbx_head_add(mbx, len);
mbx->head_len = len;
/* nothing to do if there is no data */
if (!len)
return 0;
/* Copy msg into Rx FIFO */
fm10k_mbx_read_copy(hw, mbx);
/* determine if there are any invalid lengths in message */
if (fm10k_mbx_validate_msg_size(mbx, len))
return FM10K_MBX_ERR_SIZE;
/* Update pushed */
mbx->pushed += len;
/* flush any completed messages */
for (len = fm10k_mbx_pushed_tail_len(mbx);
len && (mbx->pushed >= len);
len = fm10k_mbx_pushed_tail_len(mbx)) {
fifo->tail += len;
mbx->pushed -= len;
mbx->rx_messages++;
mbx->rx_dwords += len;
}
return 0;
}
/* pre-generated data for generating the CRC based on the poly 0xAC9A. */
static const u16 fm10k_crc_16b_table[256] = {
0x0000, 0x7956, 0xF2AC, 0x8BFA, 0xBC6D, 0xC53B, 0x4EC1, 0x3797,
0x21EF, 0x58B9, 0xD343, 0xAA15, 0x9D82, 0xE4D4, 0x6F2E, 0x1678,
0x43DE, 0x3A88, 0xB172, 0xC824, 0xFFB3, 0x86E5, 0x0D1F, 0x7449,
0x6231, 0x1B67, 0x909D, 0xE9CB, 0xDE5C, 0xA70A, 0x2CF0, 0x55A6,
0x87BC, 0xFEEA, 0x7510, 0x0C46, 0x3BD1, 0x4287, 0xC97D, 0xB02B,
0xA653, 0xDF05, 0x54FF, 0x2DA9, 0x1A3E, 0x6368, 0xE892, 0x91C4,
0xC462, 0xBD34, 0x36CE, 0x4F98, 0x780F, 0x0159, 0x8AA3, 0xF3F5,
0xE58D, 0x9CDB, 0x1721, 0x6E77, 0x59E0, 0x20B6, 0xAB4C, 0xD21A,
0x564D, 0x2F1B, 0xA4E1, 0xDDB7, 0xEA20, 0x9376, 0x188C, 0x61DA,
0x77A2, 0x0EF4, 0x850E, 0xFC58, 0xCBCF, 0xB299, 0x3963, 0x4035,
0x1593, 0x6CC5, 0xE73F, 0x9E69, 0xA9FE, 0xD0A8, 0x5B52, 0x2204,
0x347C, 0x4D2A, 0xC6D0, 0xBF86, 0x8811, 0xF147, 0x7ABD, 0x03EB,
0xD1F1, 0xA8A7, 0x235D, 0x5A0B, 0x6D9C, 0x14CA, 0x9F30, 0xE666,
0xF01E, 0x8948, 0x02B2, 0x7BE4, 0x4C73, 0x3525, 0xBEDF, 0xC789,
0x922F, 0xEB79, 0x6083, 0x19D5, 0x2E42, 0x5714, 0xDCEE, 0xA5B8,
0xB3C0, 0xCA96, 0x416C, 0x383A, 0x0FAD, 0x76FB, 0xFD01, 0x8457,
0xAC9A, 0xD5CC, 0x5E36, 0x2760, 0x10F7, 0x69A1, 0xE25B, 0x9B0D,
0x8D75, 0xF423, 0x7FD9, 0x068F, 0x3118, 0x484E, 0xC3B4, 0xBAE2,
0xEF44, 0x9612, 0x1DE8, 0x64BE, 0x5329, 0x2A7F, 0xA185, 0xD8D3,
0xCEAB, 0xB7FD, 0x3C07, 0x4551, 0x72C6, 0x0B90, 0x806A, 0xF93C,
0x2B26, 0x5270, 0xD98A, 0xA0DC, 0x974B, 0xEE1D, 0x65E7, 0x1CB1,
0x0AC9, 0x739F, 0xF865, 0x8133, 0xB6A4, 0xCFF2, 0x4408, 0x3D5E,
0x68F8, 0x11AE, 0x9A54, 0xE302, 0xD495, 0xADC3, 0x2639, 0x5F6F,
0x4917, 0x3041, 0xBBBB, 0xC2ED, 0xF57A, 0x8C2C, 0x07D6, 0x7E80,
0xFAD7, 0x8381, 0x087B, 0x712D, 0x46BA, 0x3FEC, 0xB416, 0xCD40,
0xDB38, 0xA26E, 0x2994, 0x50C2, 0x6755, 0x1E03, 0x95F9, 0xECAF,
0xB909, 0xC05F, 0x4BA5, 0x32F3, 0x0564, 0x7C32, 0xF7C8, 0x8E9E,
0x98E6, 0xE1B0, 0x6A4A, 0x131C, 0x248B, 0x5DDD, 0xD627, 0xAF71,
0x7D6B, 0x043D, 0x8FC7, 0xF691, 0xC106, 0xB850, 0x33AA, 0x4AFC,
0x5C84, 0x25D2, 0xAE28, 0xD77E, 0xE0E9, 0x99BF, 0x1245, 0x6B13,
0x3EB5, 0x47E3, 0xCC19, 0xB54F, 0x82D8, 0xFB8E, 0x7074, 0x0922,
0x1F5A, 0x660C, 0xEDF6, 0x94A0, 0xA337, 0xDA61, 0x519B, 0x28CD };
/**
* fm10k_crc_16b - Generate a 16 bit CRC for a region of 16 bit data
* @data: pointer to data to process
* @seed: seed value for CRC
* @len: length measured in 16 bits words
*
* This function will generate a CRC based on the polynomial 0xAC9A and
* whatever value is stored in the seed variable. Note that this
* value inverts the local seed and the result in order to capture all
* leading and trailing zeros.
*/
static u16 fm10k_crc_16b(const u32 *data, u16 seed, u16 len)
{
u32 result = seed;
while (len--) {
result ^= *(data++);
result = (result >> 8) ^ fm10k_crc_16b_table[result & 0xFF];
result = (result >> 8) ^ fm10k_crc_16b_table[result & 0xFF];
if (!(len--))
break;
result = (result >> 8) ^ fm10k_crc_16b_table[result & 0xFF];
result = (result >> 8) ^ fm10k_crc_16b_table[result & 0xFF];
}
return (u16)result;
}
/**
* fm10k_fifo_crc - generate a CRC based off of FIFO data
* @fifo: pointer to FIFO
* @offset: offset point for start of FIFO
* @len: number of DWORDS words to process
* @seed: seed value for CRC
*
* This function generates a CRC for some region of the FIFO
**/
static u16 fm10k_fifo_crc(struct fm10k_mbx_fifo *fifo, u16 offset,
u16 len, u16 seed)
{
u32 *data = fifo->buffer + offset;
/* track when we should cross the end of the FIFO */
offset = fifo->size - offset;
/* if we are in 2 blocks process the end of the FIFO first */
if (offset < len) {
seed = fm10k_crc_16b(data, seed, offset * 2);
data = fifo->buffer;
len -= offset;
}
/* process any remaining bits */
return fm10k_crc_16b(data, seed, len * 2);
}
/**
* fm10k_mbx_update_local_crc - Update the local CRC for outgoing data
* @mbx: pointer to mailbox
* @head: head index provided by remote mailbox
*
* This function will generate the CRC for all data from the end of the
* last head update to the current one. It uses the result of the
* previous CRC as the seed for this update. The result is stored in
* mbx->local.
**/
static void fm10k_mbx_update_local_crc(struct fm10k_mbx_info *mbx, u16 head)
{
u16 len = mbx->tail_len - fm10k_mbx_index_len(mbx, head, mbx->tail);
/* determine the offset for the start of the region to be pulled */
head = fm10k_fifo_head_offset(&mbx->tx, mbx->pulled);
/* update local CRC to include all of the pulled data */
mbx->local = fm10k_fifo_crc(&mbx->tx, head, len, mbx->local);
}
/**
* fm10k_mbx_verify_remote_crc - Verify the CRC is correct for current data
* @mbx: pointer to mailbox
*
* This function will take all data that has been provided from the remote
* end and generate a CRC for it. This is stored in mbx->remote. The
* CRC for the header is then computed and if the result is non-zero this
* is an error and we signal an error dropping all data and resetting the
* connection.
*/
static s32 fm10k_mbx_verify_remote_crc(struct fm10k_mbx_info *mbx)
{
struct fm10k_mbx_fifo *fifo = &mbx->rx;
u16 len = mbx->head_len;
u16 offset = fm10k_fifo_tail_offset(fifo, mbx->pushed) - len;
u16 crc;
/* update the remote CRC if new data has been received */
if (len)
mbx->remote = fm10k_fifo_crc(fifo, offset, len, mbx->remote);
/* process the full header as we have to validate the CRC */
crc = fm10k_crc_16b(&mbx->mbx_hdr, mbx->remote, 1);
/* notify other end if we have a problem */
return crc ? FM10K_MBX_ERR_CRC : 0;
}
/**
* fm10k_mbx_rx_ready - Indicates that a message is ready in the Rx FIFO
* @mbx: pointer to mailbox
*
* This function returns true if there is a message in the Rx FIFO to dequeue.
**/
static bool fm10k_mbx_rx_ready(struct fm10k_mbx_info *mbx)
{
u16 msg_size = fm10k_fifo_head_len(&mbx->rx);
return msg_size && (fm10k_fifo_used(&mbx->rx) >= msg_size);
}
/**
* fm10k_mbx_tx_ready - Indicates that the mailbox is in state ready for Tx
* @mbx: pointer to mailbox
* @len: verify free space is >= this value
*
* This function returns true if the mailbox is in a state ready to transmit.
**/
static bool fm10k_mbx_tx_ready(struct fm10k_mbx_info *mbx, u16 len)
{
u16 fifo_unused = fm10k_fifo_unused(&mbx->tx);
return (mbx->state == FM10K_STATE_OPEN) && (fifo_unused >= len);
}
/**
* fm10k_mbx_tx_complete - Indicates that the Tx FIFO has been emptied
* @mbx: pointer to mailbox
*
* This function returns true if the Tx FIFO is empty.
**/
static bool fm10k_mbx_tx_complete(struct fm10k_mbx_info *mbx)
{
return fm10k_fifo_empty(&mbx->tx);
}
/**
* fm10k_mbx_dequeue_rx - Dequeues the message from the head in the Rx FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function dequeues messages and hands them off to the TLV parser.
* It will return the number of messages processed when called.
**/
static u16 fm10k_mbx_dequeue_rx(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
struct fm10k_mbx_fifo *fifo = &mbx->rx;
s32 err;
u16 cnt;
/* parse Rx messages out of the Rx FIFO to empty it */
for (cnt = 0; !fm10k_fifo_empty(fifo); cnt++) {
err = fm10k_tlv_msg_parse(hw, fifo->buffer + fifo->head,
mbx, mbx->msg_data);
if (err < 0)
mbx->rx_parse_err++;
fm10k_fifo_head_drop(fifo);
}
/* shift remaining bytes back to start of FIFO */
memmove(fifo->buffer, fifo->buffer + fifo->tail, mbx->pushed << 2);
/* shift head and tail based on the memory we moved */
fifo->tail -= fifo->head;
fifo->head = 0;
return cnt;
}
/**
* fm10k_mbx_enqueue_tx - Enqueues the message to the tail of the Tx FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @msg: message array to read
*
* This function enqueues a message up to the size specified by the length
* contained in the first DWORD of the message and will place at the tail
* of the FIFO. It will return 0 on success, or a negative value on error.
**/
static s32 fm10k_mbx_enqueue_tx(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx, const u32 *msg)
{
u32 countdown = mbx->timeout;
s32 err;
switch (mbx->state) {
case FM10K_STATE_CLOSED:
case FM10K_STATE_DISCONNECT:
return FM10K_MBX_ERR_NO_MBX;
default:
break;
}
/* enqueue the message on the Tx FIFO */
err = fm10k_fifo_enqueue(&mbx->tx, msg);
/* if it failed give the FIFO a chance to drain */
while (err && countdown) {
countdown--;
udelay(mbx->udelay);
mbx->ops.process(hw, mbx);
err = fm10k_fifo_enqueue(&mbx->tx, msg);
}
/* if we failed treat the error */
if (err) {
mbx->timeout = 0;
mbx->tx_busy++;
}
/* begin processing message, ignore errors as this is just meant
* to start the mailbox flow so we are not concerned if there
* is a bad error, or the mailbox is already busy with a request
*/
if (!mbx->tail_len)
mbx->ops.process(hw, mbx);
return 0;
}
/**
* fm10k_mbx_read - Copies the mbmem to local message buffer
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function copies the message from the mbmem to the message array
**/
static s32 fm10k_mbx_read(struct fm10k_hw *hw, struct fm10k_mbx_info *mbx)
{
/* only allow one reader in here at a time */
if (mbx->mbx_hdr)
return FM10K_MBX_ERR_BUSY;
/* read to capture initial interrupt bits */
if (fm10k_read_reg(hw, mbx->mbx_reg) & FM10K_MBX_REQ_INTERRUPT)
mbx->mbx_lock = FM10K_MBX_ACK;
/* write back interrupt bits to clear */
fm10k_write_reg(hw, mbx->mbx_reg,
FM10K_MBX_REQ_INTERRUPT | FM10K_MBX_ACK_INTERRUPT);
/* read remote header */
mbx->mbx_hdr = fm10k_read_reg(hw, mbx->mbmem_reg ^ mbx->mbmem_len);
return 0;
}
/**
* fm10k_mbx_write - Copies the local message buffer to mbmem
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function copies the message from the message array to mbmem
**/
static void fm10k_mbx_write(struct fm10k_hw *hw, struct fm10k_mbx_info *mbx)
{
u32 mbmem = mbx->mbmem_reg;
/* write new msg header to notify recipient of change */
fm10k_write_reg(hw, mbmem, mbx->mbx_hdr);
/* write mailbox to send interrupt */
if (mbx->mbx_lock)
fm10k_write_reg(hw, mbx->mbx_reg, mbx->mbx_lock);
/* we no longer are using the header so free it */
mbx->mbx_hdr = 0;
mbx->mbx_lock = 0;
}
/**
* fm10k_mbx_create_connect_hdr - Generate a connect mailbox header
* @mbx: pointer to mailbox
*
* This function returns a connection mailbox header
**/
static void fm10k_mbx_create_connect_hdr(struct fm10k_mbx_info *mbx)
{
mbx->mbx_lock |= FM10K_MBX_REQ;
mbx->mbx_hdr = FM10K_MSG_HDR_FIELD_SET(FM10K_MSG_CONNECT, TYPE) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, HEAD) |
FM10K_MSG_HDR_FIELD_SET(mbx->rx.size - 1, CONNECT_SIZE);
}
/**
* fm10k_mbx_create_data_hdr - Generate a data mailbox header
* @mbx: pointer to mailbox
*
* This function returns a data mailbox header
**/
static void fm10k_mbx_create_data_hdr(struct fm10k_mbx_info *mbx)
{
u32 hdr = FM10K_MSG_HDR_FIELD_SET(FM10K_MSG_DATA, TYPE) |
FM10K_MSG_HDR_FIELD_SET(mbx->tail, TAIL) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, HEAD);
struct fm10k_mbx_fifo *fifo = &mbx->tx;
u16 crc;
if (mbx->tail_len)
mbx->mbx_lock |= FM10K_MBX_REQ;
/* generate CRC for data in flight and header */
crc = fm10k_fifo_crc(fifo, fm10k_fifo_head_offset(fifo, mbx->pulled),
mbx->tail_len, mbx->local);
crc = fm10k_crc_16b(&hdr, crc, 1);
/* load header to memory to be written */
mbx->mbx_hdr = hdr | FM10K_MSG_HDR_FIELD_SET(crc, CRC);
}
/**
* fm10k_mbx_create_disconnect_hdr - Generate a disconnect mailbox header
* @mbx: pointer to mailbox
*
* This function returns a disconnect mailbox header
**/
static void fm10k_mbx_create_disconnect_hdr(struct fm10k_mbx_info *mbx)
{
u32 hdr = FM10K_MSG_HDR_FIELD_SET(FM10K_MSG_DISCONNECT, TYPE) |
FM10K_MSG_HDR_FIELD_SET(mbx->tail, TAIL) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, HEAD);
u16 crc = fm10k_crc_16b(&hdr, mbx->local, 1);
mbx->mbx_lock |= FM10K_MBX_ACK;
/* load header to memory to be written */
mbx->mbx_hdr = hdr | FM10K_MSG_HDR_FIELD_SET(crc, CRC);
}
/**
* fm10k_mbx_create_fake_disconnect_hdr - Generate a false disconnect mbox hdr
* @mbx: pointer to mailbox
*
* This function creates a fake disconnect header for loading into remote
* mailbox header. The primary purpose is to prevent errors on immediate
* start up after mbx->connect.
**/
static void fm10k_mbx_create_fake_disconnect_hdr(struct fm10k_mbx_info *mbx)
{
u32 hdr = FM10K_MSG_HDR_FIELD_SET(FM10K_MSG_DISCONNECT, TYPE) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, TAIL) |
FM10K_MSG_HDR_FIELD_SET(mbx->tail, HEAD);
u16 crc = fm10k_crc_16b(&hdr, mbx->local, 1);
mbx->mbx_lock |= FM10K_MBX_ACK;
/* load header to memory to be written */
mbx->mbx_hdr = hdr | FM10K_MSG_HDR_FIELD_SET(crc, CRC);
}
/**
* fm10k_mbx_create_error_msg - Generate an error message
* @mbx: pointer to mailbox
* @err: local error encountered
*
* This function will interpret the error provided by err, and based on
* that it may shift the message by 1 DWORD and then place an error header
* at the start of the message.
**/
static void fm10k_mbx_create_error_msg(struct fm10k_mbx_info *mbx, s32 err)
{
/* only generate an error message for these types */
switch (err) {
case FM10K_MBX_ERR_TAIL:
case FM10K_MBX_ERR_HEAD:
case FM10K_MBX_ERR_TYPE:
case FM10K_MBX_ERR_SIZE:
case FM10K_MBX_ERR_RSVD0:
case FM10K_MBX_ERR_CRC:
break;
default:
return;
}
mbx->mbx_lock |= FM10K_MBX_REQ;
mbx->mbx_hdr = FM10K_MSG_HDR_FIELD_SET(FM10K_MSG_ERROR, TYPE) |
FM10K_MSG_HDR_FIELD_SET(err, ERR_NO) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, HEAD);
}
/**
* fm10k_mbx_validate_msg_hdr - Validate common fields in the message header
* @mbx: pointer to mailbox
*
* This function will parse up the fields in the mailbox header and return
* an error if the header contains any of a number of invalid configurations
* including unrecognized type, invalid route, or a malformed message.
**/
static s32 fm10k_mbx_validate_msg_hdr(struct fm10k_mbx_info *mbx)
{
u16 type, rsvd0, head, tail, size;
const u32 *hdr = &mbx->mbx_hdr;
type = FM10K_MSG_HDR_FIELD_GET(*hdr, TYPE);
rsvd0 = FM10K_MSG_HDR_FIELD_GET(*hdr, RSVD0);
tail = FM10K_MSG_HDR_FIELD_GET(*hdr, TAIL);
head = FM10K_MSG_HDR_FIELD_GET(*hdr, HEAD);
size = FM10K_MSG_HDR_FIELD_GET(*hdr, CONNECT_SIZE);
if (rsvd0)
return FM10K_MBX_ERR_RSVD0;
switch (type) {
case FM10K_MSG_DISCONNECT:
/* validate that all data has been received */
if (tail != mbx->head)
return FM10K_MBX_ERR_TAIL;
fallthrough;
case FM10K_MSG_DATA:
/* validate that head is moving correctly */
if (!head || (head == FM10K_MSG_HDR_MASK(HEAD)))
return FM10K_MBX_ERR_HEAD;
if (fm10k_mbx_index_len(mbx, head, mbx->tail) > mbx->tail_len)
return FM10K_MBX_ERR_HEAD;
/* validate that tail is moving correctly */
if (!tail || (tail == FM10K_MSG_HDR_MASK(TAIL)))
return FM10K_MBX_ERR_TAIL;
if (fm10k_mbx_index_len(mbx, mbx->head, tail) < mbx->mbmem_len)
break;
return FM10K_MBX_ERR_TAIL;
case FM10K_MSG_CONNECT:
/* validate size is in range and is power of 2 mask */
if ((size < FM10K_VFMBX_MSG_MTU) || (size & (size + 1)))
return FM10K_MBX_ERR_SIZE;
fallthrough;
case FM10K_MSG_ERROR:
if (!head || (head == FM10K_MSG_HDR_MASK(HEAD)))
return FM10K_MBX_ERR_HEAD;
/* neither create nor error include a tail offset */
if (tail)
return FM10K_MBX_ERR_TAIL;
break;
default:
return FM10K_MBX_ERR_TYPE;
}
return 0;
}
/**
* fm10k_mbx_create_reply - Generate reply based on state and remote head
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @head: acknowledgement number
*
* This function will generate an outgoing message based on the current
* mailbox state and the remote FIFO head. It will return the length
* of the outgoing message excluding header on success, and a negative value
* on error.
**/
static s32 fm10k_mbx_create_reply(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx, u16 head)
{
switch (mbx->state) {
case FM10K_STATE_OPEN:
case FM10K_STATE_DISCONNECT:
/* update our checksum for the outgoing data */
fm10k_mbx_update_local_crc(mbx, head);
/* as long as other end recognizes us keep sending data */
fm10k_mbx_pull_head(hw, mbx, head);
/* generate new header based on data */
if (mbx->tail_len || (mbx->state == FM10K_STATE_OPEN))
fm10k_mbx_create_data_hdr(mbx);
else
fm10k_mbx_create_disconnect_hdr(mbx);
break;
case FM10K_STATE_CONNECT:
/* send disconnect even if we aren't connected */
fm10k_mbx_create_connect_hdr(mbx);
break;
case FM10K_STATE_CLOSED:
/* generate new header based on data */
fm10k_mbx_create_disconnect_hdr(mbx);
break;
default:
break;
}
return 0;
}
/**
* fm10k_mbx_reset_work- Reset internal pointers for any pending work
* @mbx: pointer to mailbox
*
* This function will reset all internal pointers so any work in progress
* is dropped. This call should occur every time we transition from the
* open state to the connect state.
**/
static void fm10k_mbx_reset_work(struct fm10k_mbx_info *mbx)
{
u16 len, head, ack;
/* reset our outgoing max size back to Rx limits */
mbx->max_size = mbx->rx.size - 1;
/* update mbx->pulled to account for tail_len and ack */
head = FM10K_MSG_HDR_FIELD_GET(mbx->mbx_hdr, HEAD);
ack = fm10k_mbx_index_len(mbx, head, mbx->tail);
mbx->pulled += mbx->tail_len - ack;
/* now drop any messages which have started or finished transmitting */
while (fm10k_fifo_head_len(&mbx->tx) && mbx->pulled) {
len = fm10k_fifo_head_drop(&mbx->tx);
mbx->tx_dropped++;
if (mbx->pulled >= len)
mbx->pulled -= len;
else
mbx->pulled = 0;
}
/* just do a quick resysnc to start of message */
mbx->pushed = 0;
mbx->pulled = 0;
mbx->tail_len = 0;
mbx->head_len = 0;
mbx->rx.tail = 0;
mbx->rx.head = 0;
}
/**
* fm10k_mbx_update_max_size - Update the max_size and drop any large messages
* @mbx: pointer to mailbox
* @size: new value for max_size
*
* This function updates the max_size value and drops any outgoing messages
* at the head of the Tx FIFO if they are larger than max_size. It does not
* drop all messages, as this is too difficult to parse and remove them from
* the FIFO. Instead, rely on the checking to ensure that messages larger
* than max_size aren't pushed into the memory buffer.
**/
static void fm10k_mbx_update_max_size(struct fm10k_mbx_info *mbx, u16 size)
{
u16 len;
mbx->max_size = size;
/* flush any oversized messages from the queue */
for (len = fm10k_fifo_head_len(&mbx->tx);
len > size;
len = fm10k_fifo_head_len(&mbx->tx)) {
fm10k_fifo_head_drop(&mbx->tx);
mbx->tx_dropped++;
}
}
/**
* fm10k_mbx_connect_reset - Reset following request for reset
* @mbx: pointer to mailbox
*
* This function resets the mailbox to either a disconnected state
* or a connect state depending on the current mailbox state
**/
static void fm10k_mbx_connect_reset(struct fm10k_mbx_info *mbx)
{
/* just do a quick resysnc to start of frame */
fm10k_mbx_reset_work(mbx);
/* reset CRC seeds */
mbx->local = FM10K_MBX_CRC_SEED;
mbx->remote = FM10K_MBX_CRC_SEED;
/* we cannot exit connect until the size is good */
if (mbx->state == FM10K_STATE_OPEN)
mbx->state = FM10K_STATE_CONNECT;
else
mbx->state = FM10K_STATE_CLOSED;
}
/**
* fm10k_mbx_process_connect - Process connect header
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will read an incoming connect header and reply with the
* appropriate message. It will return a value indicating the number of
* data DWORDs on success, or will return a negative value on failure.
**/
static s32 fm10k_mbx_process_connect(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
const enum fm10k_mbx_state state = mbx->state;
const u32 *hdr = &mbx->mbx_hdr;
u16 size, head;
/* we will need to pull all of the fields for verification */
size = FM10K_MSG_HDR_FIELD_GET(*hdr, CONNECT_SIZE);
head = FM10K_MSG_HDR_FIELD_GET(*hdr, HEAD);
switch (state) {
case FM10K_STATE_DISCONNECT:
case FM10K_STATE_OPEN:
/* reset any in-progress work */
fm10k_mbx_connect_reset(mbx);
break;
case FM10K_STATE_CONNECT:
/* we cannot exit connect until the size is good */
if (size > mbx->rx.size) {
mbx->max_size = mbx->rx.size - 1;
} else {
/* record the remote system requesting connection */
mbx->state = FM10K_STATE_OPEN;
fm10k_mbx_update_max_size(mbx, size);
}
break;
default:
break;
}
/* align our tail index to remote head index */
mbx->tail = head;
return fm10k_mbx_create_reply(hw, mbx, head);
}
/**
* fm10k_mbx_process_data - Process data header
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will read an incoming data header and reply with the
* appropriate message. It will return a value indicating the number of
* data DWORDs on success, or will return a negative value on failure.
**/
static s32 fm10k_mbx_process_data(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
const u32 *hdr = &mbx->mbx_hdr;
u16 head, tail;
s32 err;
/* we will need to pull all of the fields for verification */
head = FM10K_MSG_HDR_FIELD_GET(*hdr, HEAD);
tail = FM10K_MSG_HDR_FIELD_GET(*hdr, TAIL);
/* if we are in connect just update our data and go */
if (mbx->state == FM10K_STATE_CONNECT) {
mbx->tail = head;
mbx->state = FM10K_STATE_OPEN;
}
/* abort on message size errors */
err = fm10k_mbx_push_tail(hw, mbx, tail);
if (err < 0)
return err;
/* verify the checksum on the incoming data */
err = fm10k_mbx_verify_remote_crc(mbx);
if (err)
return err;
/* process messages if we have received any */
fm10k_mbx_dequeue_rx(hw, mbx);
return fm10k_mbx_create_reply(hw, mbx, head);
}
/**
* fm10k_mbx_process_disconnect - Process disconnect header
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will read an incoming disconnect header and reply with the
* appropriate message. It will return a value indicating the number of
* data DWORDs on success, or will return a negative value on failure.
**/
static s32 fm10k_mbx_process_disconnect(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
const enum fm10k_mbx_state state = mbx->state;
const u32 *hdr = &mbx->mbx_hdr;
u16 head;
s32 err;
/* we will need to pull the header field for verification */
head = FM10K_MSG_HDR_FIELD_GET(*hdr, HEAD);
/* We should not be receiving disconnect if Rx is incomplete */
if (mbx->pushed)
return FM10K_MBX_ERR_TAIL;
/* we have already verified mbx->head == tail so we know this is 0 */
mbx->head_len = 0;
/* verify the checksum on the incoming header is correct */
err = fm10k_mbx_verify_remote_crc(mbx);
if (err)
return err;
switch (state) {
case FM10K_STATE_DISCONNECT:
case FM10K_STATE_OPEN:
/* state doesn't change if we still have work to do */
if (!fm10k_mbx_tx_complete(mbx))
break;
/* verify the head indicates we completed all transmits */
if (head != mbx->tail)
return FM10K_MBX_ERR_HEAD;
/* reset any in-progress work */
fm10k_mbx_connect_reset(mbx);
break;
default:
break;
}
return fm10k_mbx_create_reply(hw, mbx, head);
}
/**
* fm10k_mbx_process_error - Process error header
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will read an incoming error header and reply with the
* appropriate message. It will return a value indicating the number of
* data DWORDs on success, or will return a negative value on failure.
**/
static s32 fm10k_mbx_process_error(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
const u32 *hdr = &mbx->mbx_hdr;
u16 head;
/* we will need to pull all of the fields for verification */
head = FM10K_MSG_HDR_FIELD_GET(*hdr, HEAD);
switch (mbx->state) {
case FM10K_STATE_OPEN:
case FM10K_STATE_DISCONNECT:
/* flush any uncompleted work */
fm10k_mbx_reset_work(mbx);
/* reset CRC seeds */
mbx->local = FM10K_MBX_CRC_SEED;
mbx->remote = FM10K_MBX_CRC_SEED;
/* reset tail index and size to prepare for reconnect */
mbx->tail = head;
/* if open then reset max_size and go back to connect */
if (mbx->state == FM10K_STATE_OPEN) {
mbx->state = FM10K_STATE_CONNECT;
break;
}
/* send a connect message to get data flowing again */
fm10k_mbx_create_connect_hdr(mbx);
return 0;
default:
break;
}
return fm10k_mbx_create_reply(hw, mbx, mbx->tail);
}
/**
* fm10k_mbx_process - Process mailbox interrupt
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will process incoming mailbox events and generate mailbox
* replies. It will return a value indicating the number of DWORDs
* transmitted excluding header on success or a negative value on error.
**/
static s32 fm10k_mbx_process(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
s32 err;
/* we do not read mailbox if closed */
if (mbx->state == FM10K_STATE_CLOSED)
return 0;
/* copy data from mailbox */
err = fm10k_mbx_read(hw, mbx);
if (err)
return err;
/* validate type, source, and destination */
err = fm10k_mbx_validate_msg_hdr(mbx);
if (err < 0)
goto msg_err;
switch (FM10K_MSG_HDR_FIELD_GET(mbx->mbx_hdr, TYPE)) {
case FM10K_MSG_CONNECT:
err = fm10k_mbx_process_connect(hw, mbx);
break;
case FM10K_MSG_DATA:
err = fm10k_mbx_process_data(hw, mbx);
break;
case FM10K_MSG_DISCONNECT:
err = fm10k_mbx_process_disconnect(hw, mbx);
break;
case FM10K_MSG_ERROR:
err = fm10k_mbx_process_error(hw, mbx);
break;
default:
err = FM10K_MBX_ERR_TYPE;
break;
}
msg_err:
/* notify partner of errors on our end */
if (err < 0)
fm10k_mbx_create_error_msg(mbx, err);
/* copy data from mailbox */
fm10k_mbx_write(hw, mbx);
return err;
}
/**
* fm10k_mbx_disconnect - Shutdown mailbox connection
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will shut down the mailbox. It places the mailbox first
* in the disconnect state, it then allows up to a predefined timeout for
* the mailbox to transition to close on its own. If this does not occur
* then the mailbox will be forced into the closed state.
*
* Any mailbox transactions not completed before calling this function
* are not guaranteed to complete and may be dropped.
**/
static void fm10k_mbx_disconnect(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
int timeout = mbx->timeout ? FM10K_MBX_DISCONNECT_TIMEOUT : 0;
/* Place mbx in ready to disconnect state */
mbx->state = FM10K_STATE_DISCONNECT;
/* trigger interrupt to start shutdown process */
fm10k_write_reg(hw, mbx->mbx_reg, FM10K_MBX_REQ |
FM10K_MBX_INTERRUPT_DISABLE);
do {
udelay(FM10K_MBX_POLL_DELAY);
mbx->ops.process(hw, mbx);
timeout -= FM10K_MBX_POLL_DELAY;
} while ((timeout > 0) && (mbx->state != FM10K_STATE_CLOSED));
/* in case we didn't close, just force the mailbox into shutdown and
* drop all left over messages in the FIFO.
*/
fm10k_mbx_connect_reset(mbx);
fm10k_fifo_drop_all(&mbx->tx);
fm10k_write_reg(hw, mbx->mbmem_reg, 0);
}
/**
* fm10k_mbx_connect - Start mailbox connection
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will initiate a mailbox connection. It will populate the
* mailbox with a broadcast connect message and then initialize the lock.
* This is safe since the connect message is a single DWORD so the mailbox
* transaction is guaranteed to be atomic.
*
* This function will return an error if the mailbox has not been initiated
* or is currently in use.
**/
static s32 fm10k_mbx_connect(struct fm10k_hw *hw, struct fm10k_mbx_info *mbx)
{
/* we cannot connect an uninitialized mailbox */
if (!mbx->rx.buffer)
return FM10K_MBX_ERR_NO_SPACE;
/* we cannot connect an already connected mailbox */
if (mbx->state != FM10K_STATE_CLOSED)
return FM10K_MBX_ERR_BUSY;
/* mailbox timeout can now become active */
mbx->timeout = FM10K_MBX_INIT_TIMEOUT;
/* Place mbx in ready to connect state */
mbx->state = FM10K_STATE_CONNECT;
fm10k_mbx_reset_work(mbx);
/* initialize header of remote mailbox */
fm10k_mbx_create_fake_disconnect_hdr(mbx);
fm10k_write_reg(hw, mbx->mbmem_reg ^ mbx->mbmem_len, mbx->mbx_hdr);
/* enable interrupt and notify other party of new message */
mbx->mbx_lock = FM10K_MBX_REQ_INTERRUPT | FM10K_MBX_ACK_INTERRUPT |
FM10K_MBX_INTERRUPT_ENABLE;
/* generate and load connect header into mailbox */
fm10k_mbx_create_connect_hdr(mbx);
fm10k_mbx_write(hw, mbx);
return 0;
}
/**
* fm10k_mbx_validate_handlers - Validate layout of message parsing data
* @msg_data: handlers for mailbox events
*
* This function validates the layout of the message parsing data. This
* should be mostly static, but it is important to catch any errors that
* are made when constructing the parsers.
**/
static s32 fm10k_mbx_validate_handlers(const struct fm10k_msg_data *msg_data)
{
const struct fm10k_tlv_attr *attr;
unsigned int id;
/* Allow NULL mailboxes that transmit but don't receive */
if (!msg_data)
return 0;
while (msg_data->id != FM10K_TLV_ERROR) {
/* all messages should have a function handler */
if (!msg_data->func)
return FM10K_ERR_PARAM;
/* parser is optional */
attr = msg_data->attr;
if (attr) {
while (attr->id != FM10K_TLV_ERROR) {
id = attr->id;
attr++;
/* ID should always be increasing */
if (id >= attr->id)
return FM10K_ERR_PARAM;
/* ID should fit in results array */
if (id >= FM10K_TLV_RESULTS_MAX)
return FM10K_ERR_PARAM;
}
/* verify terminator is in the list */
if (attr->id != FM10K_TLV_ERROR)
return FM10K_ERR_PARAM;
}
id = msg_data->id;
msg_data++;
/* ID should always be increasing */
if (id >= msg_data->id)
return FM10K_ERR_PARAM;
}
/* verify terminator is in the list */
if ((msg_data->id != FM10K_TLV_ERROR) || !msg_data->func)
return FM10K_ERR_PARAM;
return 0;
}
/**
* fm10k_mbx_register_handlers - Register a set of handler ops for mailbox
* @mbx: pointer to mailbox
* @msg_data: handlers for mailbox events
*
* This function associates a set of message handling ops with a mailbox.
**/
static s32 fm10k_mbx_register_handlers(struct fm10k_mbx_info *mbx,
const struct fm10k_msg_data *msg_data)
{
/* validate layout of handlers before assigning them */
if (fm10k_mbx_validate_handlers(msg_data))
return FM10K_ERR_PARAM;
/* initialize the message handlers */
mbx->msg_data = msg_data;
return 0;
}
/**
* fm10k_pfvf_mbx_init - Initialize mailbox memory for PF/VF mailbox
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @msg_data: handlers for mailbox events
* @id: ID reference for PF as it supports up to 64 PF/VF mailboxes
*
* This function initializes the mailbox for use. It will split the
* buffer provided and use that to populate both the Tx and Rx FIFO by
* evenly splitting it. In order to allow for easy masking of head/tail
* the value reported in size must be a power of 2 and is reported in
* DWORDs, not bytes. Any invalid values will cause the mailbox to return
* error.
**/
s32 fm10k_pfvf_mbx_init(struct fm10k_hw *hw, struct fm10k_mbx_info *mbx,
const struct fm10k_msg_data *msg_data, u8 id)
{
/* initialize registers */
switch (hw->mac.type) {
case fm10k_mac_vf:
mbx->mbx_reg = FM10K_VFMBX;
mbx->mbmem_reg = FM10K_VFMBMEM(FM10K_VFMBMEM_VF_XOR);
break;
case fm10k_mac_pf:
/* there are only 64 VF <-> PF mailboxes */
if (id < 64) {
mbx->mbx_reg = FM10K_MBX(id);
mbx->mbmem_reg = FM10K_MBMEM_VF(id, 0);
break;
}
fallthrough;
default:
return FM10K_MBX_ERR_NO_MBX;
}
/* start out in closed state */
mbx->state = FM10K_STATE_CLOSED;
/* validate layout of handlers before assigning them */
if (fm10k_mbx_validate_handlers(msg_data))
return FM10K_ERR_PARAM;
/* initialize the message handlers */
mbx->msg_data = msg_data;
/* start mailbox as timed out and let the reset_hw call
* set the timeout value to begin communications
*/
mbx->timeout = 0;
mbx->udelay = FM10K_MBX_INIT_DELAY;
/* initialize tail and head */
mbx->tail = 1;
mbx->head = 1;
/* initialize CRC seeds */
mbx->local = FM10K_MBX_CRC_SEED;
mbx->remote = FM10K_MBX_CRC_SEED;
/* Split buffer for use by Tx/Rx FIFOs */
mbx->max_size = FM10K_MBX_MSG_MAX_SIZE;
mbx->mbmem_len = FM10K_VFMBMEM_VF_XOR;
/* initialize the FIFOs, sizes are in 4 byte increments */
fm10k_fifo_init(&mbx->tx, mbx->buffer, FM10K_MBX_TX_BUFFER_SIZE);
fm10k_fifo_init(&mbx->rx, &mbx->buffer[FM10K_MBX_TX_BUFFER_SIZE],
FM10K_MBX_RX_BUFFER_SIZE);
/* initialize function pointers */
mbx->ops.connect = fm10k_mbx_connect;
mbx->ops.disconnect = fm10k_mbx_disconnect;
mbx->ops.rx_ready = fm10k_mbx_rx_ready;
mbx->ops.tx_ready = fm10k_mbx_tx_ready;
mbx->ops.tx_complete = fm10k_mbx_tx_complete;
mbx->ops.enqueue_tx = fm10k_mbx_enqueue_tx;
mbx->ops.process = fm10k_mbx_process;
mbx->ops.register_handlers = fm10k_mbx_register_handlers;
return 0;
}
/**
* fm10k_sm_mbx_create_data_hdr - Generate a mailbox header for local FIFO
* @mbx: pointer to mailbox
*
* This function returns a data mailbox header
**/
static void fm10k_sm_mbx_create_data_hdr(struct fm10k_mbx_info *mbx)
{
if (mbx->tail_len)
mbx->mbx_lock |= FM10K_MBX_REQ;
mbx->mbx_hdr = FM10K_MSG_HDR_FIELD_SET(mbx->tail, SM_TAIL) |
FM10K_MSG_HDR_FIELD_SET(mbx->remote, SM_VER) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, SM_HEAD);
}
/**
* fm10k_sm_mbx_create_connect_hdr - Generate a mailbox header for local FIFO
* @mbx: pointer to mailbox
* @err: error flags to report if any
*
* This function returns a connection mailbox header
**/
static void fm10k_sm_mbx_create_connect_hdr(struct fm10k_mbx_info *mbx, u8 err)
{
if (mbx->local)
mbx->mbx_lock |= FM10K_MBX_REQ;
mbx->mbx_hdr = FM10K_MSG_HDR_FIELD_SET(mbx->tail, SM_TAIL) |
FM10K_MSG_HDR_FIELD_SET(mbx->remote, SM_VER) |
FM10K_MSG_HDR_FIELD_SET(mbx->head, SM_HEAD) |
FM10K_MSG_HDR_FIELD_SET(err, SM_ERR);
}
/**
* fm10k_sm_mbx_connect_reset - Reset following request for reset
* @mbx: pointer to mailbox
*
* This function resets the mailbox to a just connected state
**/
static void fm10k_sm_mbx_connect_reset(struct fm10k_mbx_info *mbx)
{
/* flush any uncompleted work */
fm10k_mbx_reset_work(mbx);
/* set local version to max and remote version to 0 */
mbx->local = FM10K_SM_MBX_VERSION;
mbx->remote = 0;
/* initialize tail and head */
mbx->tail = 1;
mbx->head = 1;
/* reset state back to connect */
mbx->state = FM10K_STATE_CONNECT;
}
/**
* fm10k_sm_mbx_connect - Start switch manager mailbox connection
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will initiate a mailbox connection with the switch
* manager. To do this it will first disconnect the mailbox, and then
* reconnect it in order to complete a reset of the mailbox.
*
* This function will return an error if the mailbox has not been initiated
* or is currently in use.
**/
static s32 fm10k_sm_mbx_connect(struct fm10k_hw *hw, struct fm10k_mbx_info *mbx)
{
/* we cannot connect an uninitialized mailbox */
if (!mbx->rx.buffer)
return FM10K_MBX_ERR_NO_SPACE;
/* we cannot connect an already connected mailbox */
if (mbx->state != FM10K_STATE_CLOSED)
return FM10K_MBX_ERR_BUSY;
/* mailbox timeout can now become active */
mbx->timeout = FM10K_MBX_INIT_TIMEOUT;
/* Place mbx in ready to connect state */
mbx->state = FM10K_STATE_CONNECT;
mbx->max_size = FM10K_MBX_MSG_MAX_SIZE;
/* reset interface back to connect */
fm10k_sm_mbx_connect_reset(mbx);
/* enable interrupt and notify other party of new message */
mbx->mbx_lock = FM10K_MBX_REQ_INTERRUPT | FM10K_MBX_ACK_INTERRUPT |
FM10K_MBX_INTERRUPT_ENABLE;
/* generate and load connect header into mailbox */
fm10k_sm_mbx_create_connect_hdr(mbx, 0);
fm10k_mbx_write(hw, mbx);
return 0;
}
/**
* fm10k_sm_mbx_disconnect - Shutdown mailbox connection
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will shut down the mailbox. It places the mailbox first
* in the disconnect state, it then allows up to a predefined timeout for
* the mailbox to transition to close on its own. If this does not occur
* then the mailbox will be forced into the closed state.
*
* Any mailbox transactions not completed before calling this function
* are not guaranteed to complete and may be dropped.
**/
static void fm10k_sm_mbx_disconnect(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
int timeout = mbx->timeout ? FM10K_MBX_DISCONNECT_TIMEOUT : 0;
/* Place mbx in ready to disconnect state */
mbx->state = FM10K_STATE_DISCONNECT;
/* trigger interrupt to start shutdown process */
fm10k_write_reg(hw, mbx->mbx_reg, FM10K_MBX_REQ |
FM10K_MBX_INTERRUPT_DISABLE);
do {
udelay(FM10K_MBX_POLL_DELAY);
mbx->ops.process(hw, mbx);
timeout -= FM10K_MBX_POLL_DELAY;
} while ((timeout > 0) && (mbx->state != FM10K_STATE_CLOSED));
/* in case we didn't close just force the mailbox into shutdown */
mbx->state = FM10K_STATE_CLOSED;
mbx->remote = 0;
fm10k_mbx_reset_work(mbx);
fm10k_fifo_drop_all(&mbx->tx);
fm10k_write_reg(hw, mbx->mbmem_reg, 0);
}
/**
* fm10k_sm_mbx_validate_fifo_hdr - Validate fields in the remote FIFO header
* @mbx: pointer to mailbox
*
* This function will parse up the fields in the mailbox header and return
* an error if the header contains any of a number of invalid configurations
* including unrecognized offsets or version numbers.
**/
static s32 fm10k_sm_mbx_validate_fifo_hdr(struct fm10k_mbx_info *mbx)
{
const u32 *hdr = &mbx->mbx_hdr;
u16 tail, head, ver;
tail = FM10K_MSG_HDR_FIELD_GET(*hdr, SM_TAIL);
ver = FM10K_MSG_HDR_FIELD_GET(*hdr, SM_VER);
head = FM10K_MSG_HDR_FIELD_GET(*hdr, SM_HEAD);
switch (ver) {
case 0:
break;
case FM10K_SM_MBX_VERSION:
if (!head || head > FM10K_SM_MBX_FIFO_LEN)
return FM10K_MBX_ERR_HEAD;
if (!tail || tail > FM10K_SM_MBX_FIFO_LEN)
return FM10K_MBX_ERR_TAIL;
if (mbx->tail < head)
head += mbx->mbmem_len - 1;
if (tail < mbx->head)
tail += mbx->mbmem_len - 1;
if (fm10k_mbx_index_len(mbx, head, mbx->tail) > mbx->tail_len)
return FM10K_MBX_ERR_HEAD;
if (fm10k_mbx_index_len(mbx, mbx->head, tail) < mbx->mbmem_len)
break;
return FM10K_MBX_ERR_TAIL;
default:
return FM10K_MBX_ERR_SRC;
}
return 0;
}
/**
* fm10k_sm_mbx_process_error - Process header with error flag set
* @mbx: pointer to mailbox
*
* This function is meant to respond to a request where the error flag
* is set. As a result we will terminate a connection if one is present
* and fall back into the reset state with a connection header of version
* 0 (RESET).
**/
static void fm10k_sm_mbx_process_error(struct fm10k_mbx_info *mbx)
{
const enum fm10k_mbx_state state = mbx->state;
switch (state) {
case FM10K_STATE_DISCONNECT:
/* if there is an error just disconnect */
mbx->remote = 0;
break;
case FM10K_STATE_OPEN:
/* flush any uncompleted work */
fm10k_sm_mbx_connect_reset(mbx);
break;
case FM10K_STATE_CONNECT:
/* try connecting at lower version */
if (mbx->remote) {
while (mbx->local > 1)
mbx->local--;
mbx->remote = 0;
}
break;
default:
break;
}
fm10k_sm_mbx_create_connect_hdr(mbx, 0);
}
/**
* fm10k_sm_mbx_create_error_msg - Process an error in FIFO header
* @mbx: pointer to mailbox
* @err: local error encountered
*
* This function will interpret the error provided by err, and based on
* that it may set the error bit in the local message header
**/
static void fm10k_sm_mbx_create_error_msg(struct fm10k_mbx_info *mbx, s32 err)
{
/* only generate an error message for these types */
switch (err) {
case FM10K_MBX_ERR_TAIL:
case FM10K_MBX_ERR_HEAD:
case FM10K_MBX_ERR_SRC:
case FM10K_MBX_ERR_SIZE:
case FM10K_MBX_ERR_RSVD0:
break;
default:
return;
}
/* process it as though we received an error, and send error reply */
fm10k_sm_mbx_process_error(mbx);
fm10k_sm_mbx_create_connect_hdr(mbx, 1);
}
/**
* fm10k_sm_mbx_receive - Take message from Rx mailbox FIFO and put it in Rx
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @tail: tail index of message
*
* This function will dequeue one message from the Rx switch manager mailbox
* FIFO and place it in the Rx mailbox FIFO for processing by software.
**/
static s32 fm10k_sm_mbx_receive(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx,
u16 tail)
{
/* reduce length by 1 to convert to a mask */
u16 mbmem_len = mbx->mbmem_len - 1;
s32 err;
/* push tail in front of head */
if (tail < mbx->head)
tail += mbmem_len;
/* copy data to the Rx FIFO */
err = fm10k_mbx_push_tail(hw, mbx, tail);
if (err < 0)
return err;
/* process messages if we have received any */
fm10k_mbx_dequeue_rx(hw, mbx);
/* guarantee head aligns with the end of the last message */
mbx->head = fm10k_mbx_head_sub(mbx, mbx->pushed);
mbx->pushed = 0;
/* clear any extra bits left over since index adds 1 extra bit */
if (mbx->head > mbmem_len)
mbx->head -= mbmem_len;
return err;
}
/**
* fm10k_sm_mbx_transmit - Take message from Tx and put it in Tx mailbox FIFO
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @head: head index of message
*
* This function will dequeue one message from the Tx mailbox FIFO and place
* it in the Tx switch manager mailbox FIFO for processing by hardware.
**/
static void fm10k_sm_mbx_transmit(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx, u16 head)
{
struct fm10k_mbx_fifo *fifo = &mbx->tx;
/* reduce length by 1 to convert to a mask */
u16 mbmem_len = mbx->mbmem_len - 1;
u16 tail_len, len = 0;
/* push head behind tail */
if (mbx->tail < head)
head += mbmem_len;
fm10k_mbx_pull_head(hw, mbx, head);
/* determine msg aligned offset for end of buffer */
do {
u32 *msg;
msg = fifo->buffer + fm10k_fifo_head_offset(fifo, len);
tail_len = len;
len += FM10K_TLV_DWORD_LEN(*msg);
} while ((len <= mbx->tail_len) && (len < mbmem_len));
/* guarantee we stop on a message boundary */
if (mbx->tail_len > tail_len) {
mbx->tail = fm10k_mbx_tail_sub(mbx, mbx->tail_len - tail_len);
mbx->tail_len = tail_len;
}
/* clear any extra bits left over since index adds 1 extra bit */
if (mbx->tail > mbmem_len)
mbx->tail -= mbmem_len;
}
/**
* fm10k_sm_mbx_create_reply - Generate reply based on state and remote head
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @head: acknowledgement number
*
* This function will generate an outgoing message based on the current
* mailbox state and the remote FIFO head. It will return the length
* of the outgoing message excluding header on success, and a negative value
* on error.
**/
static void fm10k_sm_mbx_create_reply(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx, u16 head)
{
switch (mbx->state) {
case FM10K_STATE_OPEN:
case FM10K_STATE_DISCONNECT:
/* flush out Tx data */
fm10k_sm_mbx_transmit(hw, mbx, head);
/* generate new header based on data */
if (mbx->tail_len || (mbx->state == FM10K_STATE_OPEN)) {
fm10k_sm_mbx_create_data_hdr(mbx);
} else {
mbx->remote = 0;
fm10k_sm_mbx_create_connect_hdr(mbx, 0);
}
break;
case FM10K_STATE_CONNECT:
case FM10K_STATE_CLOSED:
fm10k_sm_mbx_create_connect_hdr(mbx, 0);
break;
default:
break;
}
}
/**
* fm10k_sm_mbx_process_reset - Process header with version == 0 (RESET)
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function is meant to respond to a request where the version data
* is set to 0. As such we will either terminate the connection or go
* into the connect state in order to re-establish the connection. This
* function can also be used to respond to an error as the connection
* resetting would also be a means of dealing with errors.
**/
static s32 fm10k_sm_mbx_process_reset(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
s32 err = 0;
const enum fm10k_mbx_state state = mbx->state;
switch (state) {
case FM10K_STATE_DISCONNECT:
/* drop remote connections and disconnect */
mbx->state = FM10K_STATE_CLOSED;
mbx->remote = 0;
mbx->local = 0;
break;
case FM10K_STATE_OPEN:
/* flush any incomplete work */
fm10k_sm_mbx_connect_reset(mbx);
err = FM10K_ERR_RESET_REQUESTED;
break;
case FM10K_STATE_CONNECT:
/* Update remote value to match local value */
mbx->remote = mbx->local;
break;
default:
break;
}
fm10k_sm_mbx_create_reply(hw, mbx, mbx->tail);
return err;
}
/**
* fm10k_sm_mbx_process_version_1 - Process header with version == 1
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function is meant to process messages received when the remote
* mailbox is active.
**/
static s32 fm10k_sm_mbx_process_version_1(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
const u32 *hdr = &mbx->mbx_hdr;
u16 head, tail;
s32 len;
/* pull all fields needed for verification */
tail = FM10K_MSG_HDR_FIELD_GET(*hdr, SM_TAIL);
head = FM10K_MSG_HDR_FIELD_GET(*hdr, SM_HEAD);
/* if we are in connect and wanting version 1 then start up and go */
if (mbx->state == FM10K_STATE_CONNECT) {
if (!mbx->remote)
goto send_reply;
if (mbx->remote != 1)
return FM10K_MBX_ERR_SRC;
mbx->state = FM10K_STATE_OPEN;
}
do {
/* abort on message size errors */
len = fm10k_sm_mbx_receive(hw, mbx, tail);
if (len < 0)
return len;
/* continue until we have flushed the Rx FIFO */
} while (len);
send_reply:
fm10k_sm_mbx_create_reply(hw, mbx, head);
return 0;
}
/**
* fm10k_sm_mbx_process - Process switch manager mailbox interrupt
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
*
* This function will process incoming mailbox events and generate mailbox
* replies. It will return a value indicating the number of DWORDs
* transmitted excluding header on success or a negative value on error.
**/
static s32 fm10k_sm_mbx_process(struct fm10k_hw *hw,
struct fm10k_mbx_info *mbx)
{
s32 err;
/* we do not read mailbox if closed */
if (mbx->state == FM10K_STATE_CLOSED)
return 0;
/* retrieve data from switch manager */
err = fm10k_mbx_read(hw, mbx);
if (err)
return err;
err = fm10k_sm_mbx_validate_fifo_hdr(mbx);
if (err < 0)
goto fifo_err;
if (FM10K_MSG_HDR_FIELD_GET(mbx->mbx_hdr, SM_ERR)) {
fm10k_sm_mbx_process_error(mbx);
goto fifo_err;
}
switch (FM10K_MSG_HDR_FIELD_GET(mbx->mbx_hdr, SM_VER)) {
case 0:
err = fm10k_sm_mbx_process_reset(hw, mbx);
break;
case FM10K_SM_MBX_VERSION:
err = fm10k_sm_mbx_process_version_1(hw, mbx);
break;
}
fifo_err:
if (err < 0)
fm10k_sm_mbx_create_error_msg(mbx, err);
/* report data to switch manager */
fm10k_mbx_write(hw, mbx);
return err;
}
/**
* fm10k_sm_mbx_init - Initialize mailbox memory for PF/SM mailbox
* @hw: pointer to hardware structure
* @mbx: pointer to mailbox
* @msg_data: handlers for mailbox events
*
* This function initializes the PF/SM mailbox for use. It will split the
* buffer provided and use that to populate both the Tx and Rx FIFO by
* evenly splitting it. In order to allow for easy masking of head/tail
* the value reported in size must be a power of 2 and is reported in
* DWORDs, not bytes. Any invalid values will cause the mailbox to return
* error.
**/
s32 fm10k_sm_mbx_init(struct fm10k_hw __always_unused *hw,
struct fm10k_mbx_info *mbx,
const struct fm10k_msg_data *msg_data)
{
mbx->mbx_reg = FM10K_GMBX;
mbx->mbmem_reg = FM10K_MBMEM_PF(0);
/* start out in closed state */
mbx->state = FM10K_STATE_CLOSED;
/* validate layout of handlers before assigning them */
if (fm10k_mbx_validate_handlers(msg_data))
return FM10K_ERR_PARAM;
/* initialize the message handlers */
mbx->msg_data = msg_data;
/* start mailbox as timed out and let the reset_hw call
* set the timeout value to begin communications
*/
mbx->timeout = 0;
mbx->udelay = FM10K_MBX_INIT_DELAY;
/* Split buffer for use by Tx/Rx FIFOs */
mbx->max_size = FM10K_MBX_MSG_MAX_SIZE;
mbx->mbmem_len = FM10K_MBMEM_PF_XOR;
/* initialize the FIFOs, sizes are in 4 byte increments */
fm10k_fifo_init(&mbx->tx, mbx->buffer, FM10K_MBX_TX_BUFFER_SIZE);
fm10k_fifo_init(&mbx->rx, &mbx->buffer[FM10K_MBX_TX_BUFFER_SIZE],
FM10K_MBX_RX_BUFFER_SIZE);
/* initialize function pointers */
mbx->ops.connect = fm10k_sm_mbx_connect;
mbx->ops.disconnect = fm10k_sm_mbx_disconnect;
mbx->ops.rx_ready = fm10k_mbx_rx_ready;
mbx->ops.tx_ready = fm10k_mbx_tx_ready;
mbx->ops.tx_complete = fm10k_mbx_tx_complete;
mbx->ops.enqueue_tx = fm10k_mbx_enqueue_tx;
mbx->ops.process = fm10k_sm_mbx_process;
mbx->ops.register_handlers = fm10k_mbx_register_handlers;
return 0;
}