- 根目录:
- drivers
- net
- wireless
- wl1251
- tx.c
/*
* This file is part of wl1251
*
* Copyright (c) 1998-2007 Texas Instruments Incorporated
* Copyright (C) 2008 Nokia Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include "wl1251.h"
#include "reg.h"
#include "tx.h"
#include "ps.h"
#include "io.h"
static bool wl1251_tx_double_buffer_busy(struct wl1251 *wl, u32 data_out_count)
{
int used, data_in_count;
data_in_count = wl->data_in_count;
if (data_in_count < data_out_count)
/* data_in_count has wrapped */
data_in_count += TX_STATUS_DATA_OUT_COUNT_MASK + 1;
used = data_in_count - data_out_count;
WARN_ON(used < 0);
WARN_ON(used > DP_TX_PACKET_RING_CHUNK_NUM);
if (used >= DP_TX_PACKET_RING_CHUNK_NUM)
return true;
else
return false;
}
static int wl1251_tx_path_status(struct wl1251 *wl)
{
u32 status, addr, data_out_count;
bool busy;
addr = wl->data_path->tx_control_addr;
status = wl1251_mem_read32(wl, addr);
data_out_count = status & TX_STATUS_DATA_OUT_COUNT_MASK;
busy = wl1251_tx_double_buffer_busy(wl, data_out_count);
if (busy)
return -EBUSY;
return 0;
}
static int wl1251_tx_id(struct wl1251 *wl, struct sk_buff *skb)
{
int i;
for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++)
if (wl->tx_frames[i] == NULL) {
wl->tx_frames[i] = skb;
return i;
}
return -EBUSY;
}
static void wl1251_tx_control(struct tx_double_buffer_desc *tx_hdr,
struct ieee80211_tx_info *control, u16 fc)
{
*(u16 *)&tx_hdr->control = 0;
tx_hdr->control.rate_policy = 0;
/* 802.11 packets */
tx_hdr->control.packet_type = 0;
if (control->flags & IEEE80211_TX_CTL_NO_ACK)
tx_hdr->control.ack_policy = 1;
tx_hdr->control.tx_complete = 1;
if ((fc & IEEE80211_FTYPE_DATA) &&
((fc & IEEE80211_STYPE_QOS_DATA) ||
(fc & IEEE80211_STYPE_QOS_NULLFUNC)))
tx_hdr->control.qos = 1;
}
/* RSN + MIC = 8 + 8 = 16 bytes (worst case - AES). */
#define MAX_MSDU_SECURITY_LENGTH 16
#define MAX_MPDU_SECURITY_LENGTH 16
#define WLAN_QOS_HDR_LEN 26
#define MAX_MPDU_HEADER_AND_SECURITY (MAX_MPDU_SECURITY_LENGTH + \
WLAN_QOS_HDR_LEN)
#define HW_BLOCK_SIZE 252
static void wl1251_tx_frag_block_num(struct tx_double_buffer_desc *tx_hdr)
{
u16 payload_len, frag_threshold, mem_blocks;
u16 num_mpdus, mem_blocks_per_frag;
frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD;
tx_hdr->frag_threshold = cpu_to_le16(frag_threshold);
payload_len = le16_to_cpu(tx_hdr->length) + MAX_MSDU_SECURITY_LENGTH;
if (payload_len > frag_threshold) {
mem_blocks_per_frag =
((frag_threshold + MAX_MPDU_HEADER_AND_SECURITY) /
HW_BLOCK_SIZE) + 1;
num_mpdus = payload_len / frag_threshold;
mem_blocks = num_mpdus * mem_blocks_per_frag;
payload_len -= num_mpdus * frag_threshold;
num_mpdus++;
} else {
mem_blocks_per_frag = 0;
mem_blocks = 0;
num_mpdus = 1;
}
mem_blocks += (payload_len / HW_BLOCK_SIZE) + 1;
if (num_mpdus > 1)
mem_blocks += min(num_mpdus, mem_blocks_per_frag);
tx_hdr->num_mem_blocks = mem_blocks;
}
static int wl1251_tx_fill_hdr(struct wl1251 *wl, struct sk_buff *skb,
struct ieee80211_tx_info *control)
{
struct tx_double_buffer_desc *tx_hdr;
struct ieee80211_rate *rate;
int id;
u16 fc;
if (!skb)
return -EINVAL;
id = wl1251_tx_id(wl, skb);
if (id < 0)
return id;
fc = *(u16 *)skb->data;
tx_hdr = (struct tx_double_buffer_desc *) skb_push(skb,
sizeof(*tx_hdr));
tx_hdr->length = cpu_to_le16(skb->len - sizeof(*tx_hdr));
rate = ieee80211_get_tx_rate(wl->hw, control);
tx_hdr->rate = cpu_to_le16(rate->hw_value);
tx_hdr->expiry_time = cpu_to_le32(1 << 16);
tx_hdr->id = id;
tx_hdr->xmit_queue = wl1251_tx_get_queue(skb_get_queue_mapping(skb));
wl1251_tx_control(tx_hdr, control, fc);
wl1251_tx_frag_block_num(tx_hdr);
return 0;
}
/* We copy the packet to the target */
static int wl1251_tx_send_packet(struct wl1251 *wl, struct sk_buff *skb,
struct ieee80211_tx_info *control)
{
struct tx_double_buffer_desc *tx_hdr;
int len;
u32 addr;
if (!skb)
return -EINVAL;
tx_hdr = (struct tx_double_buffer_desc *) skb->data;
if (control->control.hw_key &&
control->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
int hdrlen;
__le16 fc;
u16 length;
u8 *pos;
fc = *(__le16 *)(skb->data + sizeof(*tx_hdr));
length = le16_to_cpu(tx_hdr->length) + WL1251_TKIP_IV_SPACE;
tx_hdr->length = cpu_to_le16(length);
hdrlen = ieee80211_hdrlen(fc);
pos = skb_push(skb, WL1251_TKIP_IV_SPACE);
memmove(pos, pos + WL1251_TKIP_IV_SPACE,
sizeof(*tx_hdr) + hdrlen);
}
/* Revisit. This is a workaround for getting non-aligned packets.
This happens at least with EAPOL packets from the user space.
Our DMA requires packets to be aligned on a 4-byte boundary.
*/
if (unlikely((long)skb->data & 0x03)) {
int offset = (4 - (long)skb->data) & 0x03;
wl1251_debug(DEBUG_TX, "skb offset %d", offset);
/* check whether the current skb can be used */
if (skb_cloned(skb) || (skb_tailroom(skb) < offset)) {
struct sk_buff *newskb = skb_copy_expand(skb, 0, 3,
GFP_KERNEL);
if (unlikely(newskb == NULL)) {
wl1251_error("Can't allocate skb!");
return -EINVAL;
}
tx_hdr = (struct tx_double_buffer_desc *) newskb->data;
dev_kfree_skb_any(skb);
wl->tx_frames[tx_hdr->id] = skb = newskb;
offset = (4 - (long)skb->data) & 0x03;
wl1251_debug(DEBUG_TX, "new skb offset %d", offset);
}
/* align the buffer on a 4-byte boundary */
if (offset) {
unsigned char *src = skb->data;
skb_reserve(skb, offset);
memmove(skb->data, src, skb->len);
tx_hdr = (struct tx_double_buffer_desc *) skb->data;
}
}
/* Our skb->data at this point includes the HW header */
len = WL1251_TX_ALIGN(skb->len);
if (wl->data_in_count & 0x1)
addr = wl->data_path->tx_packet_ring_addr +
wl->data_path->tx_packet_ring_chunk_size;
else
addr = wl->data_path->tx_packet_ring_addr;
wl1251_mem_write(wl, addr, skb->data, len);
wl1251_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u rate 0x%x "
"queue %d", tx_hdr->id, skb, tx_hdr->length,
tx_hdr->rate, tx_hdr->xmit_queue);
return 0;
}
static void wl1251_tx_trigger(struct wl1251 *wl)
{
u32 data, addr;
if (wl->data_in_count & 0x1) {
addr = ACX_REG_INTERRUPT_TRIG_H;
data = INTR_TRIG_TX_PROC1;
} else {
addr = ACX_REG_INTERRUPT_TRIG;
data = INTR_TRIG_TX_PROC0;
}
wl1251_reg_write32(wl, addr, data);
/* Bumping data in */
wl->data_in_count = (wl->data_in_count + 1) &
TX_STATUS_DATA_OUT_COUNT_MASK;
}
/* caller must hold wl->mutex */
static int wl1251_tx_frame(struct wl1251 *wl, struct sk_buff *skb)
{
struct ieee80211_tx_info *info;
int ret = 0;
u8 idx;
info = IEEE80211_SKB_CB(skb);
if (info->control.hw_key) {
idx = info->control.hw_key->hw_key_idx;
if (unlikely(wl->default_key != idx)) {
ret = wl1251_acx_default_key(wl, idx);
if (ret < 0)
return ret;
}
}
ret = wl1251_tx_path_status(wl);
if (ret < 0)
return ret;
ret = wl1251_tx_fill_hdr(wl, skb, info);
if (ret < 0)
return ret;
ret = wl1251_tx_send_packet(wl, skb, info);
if (ret < 0)
return ret;
wl1251_tx_trigger(wl);
return ret;
}
void wl1251_tx_work(struct work_struct *work)
{
struct wl1251 *wl = container_of(work, struct wl1251, tx_work);
struct sk_buff *skb;
bool woken_up = false;
int ret;
mutex_lock(&wl->mutex);
if (unlikely(wl->state == WL1251_STATE_OFF))
goto out;
while ((skb = skb_dequeue(&wl->tx_queue))) {
if (!woken_up) {
ret = wl1251_ps_elp_wakeup(wl);
if (ret < 0)
goto out;
woken_up = true;
}
ret = wl1251_tx_frame(wl, skb);
if (ret == -EBUSY) {
skb_queue_head(&wl->tx_queue, skb);
goto out;
} else if (ret < 0) {
dev_kfree_skb(skb);
goto out;
}
}
out:
if (woken_up)
wl1251_ps_elp_sleep(wl);
mutex_unlock(&wl->mutex);
}
static const char *wl1251_tx_parse_status(u8 status)
{
/* 8 bit status field, one character per bit plus null */
static char buf[9];
int i = 0;
memset(buf, 0, sizeof(buf));
if (status & TX_DMA_ERROR)
buf[i++] = 'm';
if (status & TX_DISABLED)
buf[i++] = 'd';
if (status & TX_RETRY_EXCEEDED)
buf[i++] = 'r';
if (status & TX_TIMEOUT)
buf[i++] = 't';
if (status & TX_KEY_NOT_FOUND)
buf[i++] = 'k';
if (status & TX_ENCRYPT_FAIL)
buf[i++] = 'e';
if (status & TX_UNAVAILABLE_PRIORITY)
buf[i++] = 'p';
/* bit 0 is unused apparently */
return buf;
}
static void wl1251_tx_packet_cb(struct wl1251 *wl,
struct tx_result *result)
{
struct ieee80211_tx_info *info;
struct sk_buff *skb;
int hdrlen;
u8 *frame;
skb = wl->tx_frames[result->id];
if (skb == NULL) {
wl1251_error("SKB for packet %d is NULL", result->id);
return;
}
info = IEEE80211_SKB_CB(skb);
if (!(info->flags & IEEE80211_TX_CTL_NO_ACK) &&
(result->status == TX_SUCCESS))
info->flags |= IEEE80211_TX_STAT_ACK;
info->status.rates[0].count = result->ack_failures + 1;
wl->stats.retry_count += result->ack_failures;
/*
* We have to remove our private TX header before pushing
* the skb back to mac80211.
*/
frame = skb_pull(skb, sizeof(struct tx_double_buffer_desc));
if (info->control.hw_key &&
info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
hdrlen = ieee80211_get_hdrlen_from_skb(skb);
memmove(frame + WL1251_TKIP_IV_SPACE, frame, hdrlen);
skb_pull(skb, WL1251_TKIP_IV_SPACE);
}
wl1251_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x"
" status 0x%x (%s)",
result->id, skb, result->ack_failures, result->rate,
result->status, wl1251_tx_parse_status(result->status));
ieee80211_tx_status(wl->hw, skb);
wl->tx_frames[result->id] = NULL;
}
/* Called upon reception of a TX complete interrupt */
void wl1251_tx_complete(struct wl1251 *wl)
{
int i, result_index, num_complete = 0, queue_len;
struct tx_result result[FW_TX_CMPLT_BLOCK_SIZE], *result_ptr;
unsigned long flags;
if (unlikely(wl->state != WL1251_STATE_ON))
return;
/* First we read the result */
wl1251_mem_read(wl, wl->data_path->tx_complete_addr,
result, sizeof(result));
result_index = wl->next_tx_complete;
for (i = 0; i < ARRAY_SIZE(result); i++) {
result_ptr = &result[result_index];
if (result_ptr->done_1 == 1 &&
result_ptr->done_2 == 1) {
wl1251_tx_packet_cb(wl, result_ptr);
result_ptr->done_1 = 0;
result_ptr->done_2 = 0;
result_index = (result_index + 1) &
(FW_TX_CMPLT_BLOCK_SIZE - 1);
num_complete++;
} else {
break;
}
}
queue_len = skb_queue_len(&wl->tx_queue);
if ((num_complete > 0) && (queue_len > 0)) {
/* firmware buffer has space, reschedule tx_work */
wl1251_debug(DEBUG_TX, "tx_complete: reschedule tx_work");
ieee80211_queue_work(wl->hw, &wl->tx_work);
}
if (wl->tx_queue_stopped &&
queue_len <= WL1251_TX_QUEUE_LOW_WATERMARK) {
/* tx_queue has space, restart queues */
wl1251_debug(DEBUG_TX, "tx_complete: waking queues");
spin_lock_irqsave(&wl->wl_lock, flags);
ieee80211_wake_queues(wl->hw);
wl->tx_queue_stopped = false;
spin_unlock_irqrestore(&wl->wl_lock, flags);
}
/* Every completed frame needs to be acknowledged */
if (num_complete) {
/*
* If we've wrapped, we have to clear
* the results in 2 steps.
*/
if (result_index > wl->next_tx_complete) {
/* Only 1 write is needed */
wl1251_mem_write(wl,
wl->data_path->tx_complete_addr +
(wl->next_tx_complete *
sizeof(struct tx_result)),
&result[wl->next_tx_complete],
num_complete *
sizeof(struct tx_result));
} else if (result_index < wl->next_tx_complete) {
/* 2 writes are needed */
wl1251_mem_write(wl,
wl->data_path->tx_complete_addr +
(wl->next_tx_complete *
sizeof(struct tx_result)),
&result[wl->next_tx_complete],
(FW_TX_CMPLT_BLOCK_SIZE -
wl->next_tx_complete) *
sizeof(struct tx_result));
wl1251_mem_write(wl,
wl->data_path->tx_complete_addr,
result,
(num_complete -
FW_TX_CMPLT_BLOCK_SIZE +
wl->next_tx_complete) *
sizeof(struct tx_result));
} else {
/* We have to write the whole array */
wl1251_mem_write(wl,
wl->data_path->tx_complete_addr,
result,
FW_TX_CMPLT_BLOCK_SIZE *
sizeof(struct tx_result));
}
}
wl->next_tx_complete = result_index;
}
/* caller must hold wl->mutex */
void wl1251_tx_flush(struct wl1251 *wl)
{
int i;
struct sk_buff *skb;
struct ieee80211_tx_info *info;
/* TX failure */
/* control->flags = 0; FIXME */
while ((skb = skb_dequeue(&wl->tx_queue))) {
info = IEEE80211_SKB_CB(skb);
wl1251_debug(DEBUG_TX, "flushing skb 0x%p", skb);
if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS))
continue;
ieee80211_tx_status(wl->hw, skb);
}
for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++)
if (wl->tx_frames[i] != NULL) {
skb = wl->tx_frames[i];
info = IEEE80211_SKB_CB(skb);
if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS))
continue;
ieee80211_tx_status(wl->hw, skb);
wl->tx_frames[i] = NULL;
}
}