/*
* This file is part of wl1271
*
* Copyright (C) 2009 Nokia Corporation
*
* Contact: Luciano Coelho <luciano.coelho@nokia.com>
*
* 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 "wl1271.h"
#include "wl1271_spi.h"
#include "wl1271_reg.h"
#include "wl1271_ps.h"
#include "wl1271_tx.h"
static int wl1271_tx_id(struct wl1271 *wl, struct sk_buff *skb)
{
int i;
for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
if (wl->tx_frames[i] == NULL) {
wl->tx_frames[i] = skb;
return i;
}
return -EBUSY;
}
static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra)
{
struct wl1271_tx_hw_descr *desc;
u32 total_len = skb->len + sizeof(struct wl1271_tx_hw_descr) + extra;
u32 total_blocks, excluded;
int id, ret = -EBUSY;
/* allocate free identifier for the packet */
id = wl1271_tx_id(wl, skb);
if (id < 0)
return id;
/* approximate the number of blocks required for this packet
in the firmware */
/* FIXME: try to figure out what is done here and make it cleaner */
total_blocks = (total_len + 20) >> TX_HW_BLOCK_SHIFT_DIV;
excluded = (total_blocks << 2) + ((total_len + 20) & 0xff) + 34;
total_blocks += (excluded > 252) ? 2 : 1;
total_blocks += TX_HW_BLOCK_SPARE;
if (total_blocks <= wl->tx_blocks_available) {
desc = (struct wl1271_tx_hw_descr *)skb_push(
skb, total_len - skb->len);
desc->extra_mem_blocks = TX_HW_BLOCK_SPARE;
desc->total_mem_blocks = total_blocks;
desc->id = id;
wl->tx_blocks_available -= total_blocks;
ret = 0;
wl1271_debug(DEBUG_TX,
"tx_allocate: size: %d, blocks: %d, id: %d",
total_len, total_blocks, id);
} else
wl->tx_frames[id] = NULL;
return ret;
}
static int wl1271_tx_fill_hdr(struct wl1271 *wl, struct sk_buff *skb,
u32 extra, struct ieee80211_tx_info *control)
{
struct wl1271_tx_hw_descr *desc;
int pad;
u16 tx_attr;
desc = (struct wl1271_tx_hw_descr *) skb->data;
/* relocate space for security header */
if (extra) {
void *framestart = skb->data + sizeof(*desc);
u16 fc = *(u16 *)(framestart + extra);
int hdrlen = ieee80211_hdrlen(cpu_to_le16(fc));
memmove(framestart, framestart + extra, hdrlen);
}
/* configure packet life time */
desc->start_time = cpu_to_le32(jiffies_to_usecs(jiffies) -
wl->time_offset);
desc->life_time = cpu_to_le16(TX_HW_MGMT_PKT_LIFETIME_TU);
/* configure the tx attributes */
tx_attr = wl->session_counter << TX_HW_ATTR_OFST_SESSION_COUNTER;
/* FIXME: do we know the packet priority? can we identify mgmt
packets, and use max prio for them at least? */
desc->tid = 0;
desc->aid = TX_HW_DEFAULT_AID;
desc->reserved = 0;
/* align the length (and store in terms of words) */
pad = WL1271_TX_ALIGN(skb->len);
desc->length = cpu_to_le16(pad >> 2);
/* calculate number of padding bytes */
pad = pad - skb->len;
tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD;
/* if the packets are destined for AP (have a STA entry) send them
with AP rate policies, otherwise use default basic rates */
if (control->control.sta)
tx_attr |= ACX_TX_AP_FULL_RATE << TX_HW_ATTR_OFST_RATE_POLICY;
desc->tx_attr = cpu_to_le16(tx_attr);
wl1271_debug(DEBUG_TX, "tx_fill_hdr: pad: %d", pad);
return 0;
}
static int wl1271_tx_send_packet(struct wl1271 *wl, struct sk_buff *skb,
struct ieee80211_tx_info *control)
{
struct wl1271_tx_hw_descr *desc;
int len;
/* FIXME: 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;
wl1271_debug(DEBUG_TX, "skb offset %d", offset);
/* check whether the current skb can be used */
if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) {
unsigned char *src = skb->data;
/* align the buffer on a 4-byte boundary */
skb_reserve(skb, offset);
memmove(skb->data, src, skb->len);
} else {
wl1271_info("No handler, fixme!");
return -EINVAL;
}
}
len = WL1271_TX_ALIGN(skb->len);
/* perform a fixed address block write with the packet */
wl1271_spi_write(wl, WL1271_SLV_MEM_DATA, skb->data, len, true);
/* write packet new counter into the write access register */
wl->tx_packets_count++;
wl1271_spi_write32(wl, WL1271_HOST_WR_ACCESS, wl->tx_packets_count);
desc = (struct wl1271_tx_hw_descr *) skb->data;
wl1271_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u (%u words)",
desc->id, skb, len, desc->length);
return 0;
}
/* caller must hold wl->mutex */
static int wl1271_tx_frame(struct wl1271 *wl, struct sk_buff *skb)
{
struct ieee80211_tx_info *info;
u32 extra = 0;
int ret = 0;
u8 idx;
if (!skb)
return -EINVAL;
info = IEEE80211_SKB_CB(skb);
if (info->control.hw_key &&
info->control.hw_key->alg == ALG_TKIP)
extra = WL1271_TKIP_IV_SPACE;
if (info->control.hw_key) {
idx = info->control.hw_key->hw_key_idx;
/* FIXME: do we have to do this if we're not using WEP? */
if (unlikely(wl->default_key != idx)) {
ret = wl1271_cmd_set_default_wep_key(wl, idx);
if (ret < 0)
return ret;
}
}
ret = wl1271_tx_allocate(wl, skb, extra);
if (ret < 0)
return ret;
ret = wl1271_tx_fill_hdr(wl, skb, extra, info);
if (ret < 0)
return ret;
ret = wl1271_tx_send_packet(wl, skb, info);
if (ret < 0)
return ret;
return ret;
}
static u32 wl1271_tx_enabled_rates_get(struct wl1271 *wl, u32 rate_set)
{
struct ieee80211_supported_band *band;
u32 enabled_rates = 0;
int bit;
band = wl->hw->wiphy->bands[wl->band];
for (bit = 0; bit < band->n_bitrates; bit++) {
if (rate_set & 0x1)
enabled_rates |= band->bitrates[bit].hw_value;
rate_set >>= 1;
}
return enabled_rates;
}
void wl1271_tx_work(struct work_struct *work)
{
struct wl1271 *wl = container_of(work, struct wl1271, tx_work);
struct sk_buff *skb;
bool woken_up = false;
u32 sta_rates = 0;
int ret;
/* check if the rates supported by the AP have changed */
if (unlikely(test_and_clear_bit(WL1271_FLAG_STA_RATES_CHANGED,
&wl->flags))) {
unsigned long flags;
spin_lock_irqsave(&wl->wl_lock, flags);
sta_rates = wl->sta_rate_set;
spin_unlock_irqrestore(&wl->wl_lock, flags);
}
mutex_lock(&wl->mutex);
if (unlikely(wl->state == WL1271_STATE_OFF))
goto out;
/* if rates have changed, re-configure the rate policy */
if (unlikely(sta_rates)) {
wl->rate_set = wl1271_tx_enabled_rates_get(wl, sta_rates);
wl1271_acx_rate_policies(wl);
}
while ((skb = skb_dequeue(&wl->tx_queue))) {
if (!woken_up) {
ret = wl1271_ps_elp_wakeup(wl, false);
if (ret < 0)
goto out;
woken_up = true;
}
ret = wl1271_tx_frame(wl, skb);
if (ret == -EBUSY) {
/* firmware buffer is full, stop queues */
wl1271_debug(DEBUG_TX, "tx_work: fw buffer full, "
"stop queues");
ieee80211_stop_queues(wl->hw);
set_bit(WL1271_FLAG_TX_QUEUE_STOPPED, &wl->flags);
skb_queue_head(&wl->tx_queue, skb);
goto out;
} else if (ret < 0) {
dev_kfree_skb(skb);
goto out;
} else if (test_and_clear_bit(WL1271_FLAG_TX_QUEUE_STOPPED,
&wl->flags)) {
/* firmware buffer has space, restart queues */
wl1271_debug(DEBUG_TX,
"complete_packet: waking queues");
ieee80211_wake_queues(wl->hw);
}
}
out:
if (woken_up)
wl1271_ps_elp_sleep(wl);
mutex_unlock(&wl->mutex);
}
static void wl1271_tx_complete_packet(struct wl1271 *wl,
struct wl1271_tx_hw_res_descr *result)
{
struct ieee80211_tx_info *info;
struct sk_buff *skb;
u16 seq;
int id = result->id;
/* check for id legality */
if (id >= ACX_TX_DESCRIPTORS || wl->tx_frames[id] == NULL) {
wl1271_warning("TX result illegal id: %d", id);
return;
}
skb = wl->tx_frames[id];
info = IEEE80211_SKB_CB(skb);
/* update packet status */
if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) {
if (result->status == TX_SUCCESS)
info->flags |= IEEE80211_TX_STAT_ACK;
if (result->status & TX_RETRY_EXCEEDED) {
/* FIXME */
/* info->status.excessive_retries = 1; */
wl->stats.excessive_retries++;
}
}
/* FIXME */
/* info->status.retry_count = result->ack_failures; */
wl->stats.retry_count += result->ack_failures;
/* update security sequence number */
seq = wl->tx_security_seq_16 +
(result->lsb_security_sequence_number -
wl->tx_security_last_seq);
wl->tx_security_last_seq = result->lsb_security_sequence_number;
if (seq < wl->tx_security_seq_16)
wl->tx_security_seq_32++;
wl->tx_security_seq_16 = seq;
/* remove private header from packet */
skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
/* remove TKIP header space if present */
if (info->control.hw_key &&
info->control.hw_key->alg == ALG_TKIP) {
int hdrlen = ieee80211_get_hdrlen_from_skb(skb);
memmove(skb->data + WL1271_TKIP_IV_SPACE, skb->data, hdrlen);
skb_pull(skb, WL1271_TKIP_IV_SPACE);
}
wl1271_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x"
" status 0x%x",
result->id, skb, result->ack_failures,
result->rate_class_index, result->status);
/* return the packet to the stack */
ieee80211_tx_status(wl->hw, skb);
wl->tx_frames[result->id] = NULL;
}
/* Called upon reception of a TX complete interrupt */
void wl1271_tx_complete(struct wl1271 *wl, u32 count)
{
struct wl1271_acx_mem_map *memmap =
(struct wl1271_acx_mem_map *)wl->target_mem_map;
u32 i;
wl1271_debug(DEBUG_TX, "tx_complete received, packets: %d", count);
/* read the tx results from the chipset */
wl1271_spi_read(wl, le32_to_cpu(memmap->tx_result),
wl->tx_res_if, sizeof(*wl->tx_res_if), false);
/* verify that the result buffer is not getting overrun */
if (count > TX_HW_RESULT_QUEUE_LEN) {
wl1271_warning("TX result overflow from chipset: %d", count);
count = TX_HW_RESULT_QUEUE_LEN;
}
/* process the results */
for (i = 0; i < count; i++) {
struct wl1271_tx_hw_res_descr *result;
u8 offset = wl->tx_results_count & TX_HW_RESULT_QUEUE_LEN_MASK;
/* process the packet */
result = &(wl->tx_res_if->tx_results_queue[offset]);
wl1271_tx_complete_packet(wl, result);
wl->tx_results_count++;
}
/* write host counter to chipset (to ack) */
wl1271_spi_write32(wl, le32_to_cpu(memmap->tx_result) +
offsetof(struct wl1271_tx_hw_res_if,
tx_result_host_counter),
le32_to_cpu(wl->tx_res_if->tx_result_fw_counter));
}
/* caller must hold wl->mutex */
void wl1271_tx_flush(struct wl1271 *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);
wl1271_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 < ACX_TX_DESCRIPTORS; 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;
}
}
