wl12xx: implement SW Tx watchdog

Track freed FW blocks during Tx. If no blocks were freed during a
predefined timeout, initiate a HW recovery. This helps in situations
when the FW watchdog fails.

Don't trigger recovery during activities that can temporarily stop
Tx. This includes:
- scanning
- buffering packets for sleeping stations (AP role)
- ROC on any role

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
This commit is contained in:
Arik Nemtsov 2012-03-03 22:18:00 +02:00 committed by Luciano Coelho
parent 8ccd16e6cb
commit 55df5afb13
7 changed files with 135 additions and 0 deletions

View File

@ -1818,6 +1818,14 @@ int wl12xx_croc(struct wl1271 *wl, u8 role_id)
goto out;
__clear_bit(role_id, wl->roc_map);
/*
* Rearm the tx watchdog when removing the last ROC. This prevents
* recoveries due to just finished ROCs - when Tx hasn't yet had
* a chance to get out.
*/
if (find_first_bit(wl->roc_map, WL12XX_MAX_ROLES) >= WL12XX_MAX_ROLES)
wl12xx_rearm_tx_watchdog_locked(wl);
out:
return ret;
}

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@ -690,6 +690,9 @@ struct conf_tx_settings {
*/
u8 tmpl_short_retry_limit;
u8 tmpl_long_retry_limit;
/* Time in ms for Tx watchdog timer to expire */
u32 tx_watchdog_timeout;
};
enum {

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@ -217,6 +217,7 @@ static struct conf_drv_settings default_conf = {
.basic_rate_5 = CONF_HW_BIT_RATE_6MBPS,
.tmpl_short_retry_limit = 10,
.tmpl_long_retry_limit = 10,
.tx_watchdog_timeout = 5000,
},
.conn = {
.wake_up_event = CONF_WAKE_UP_EVENT_DTIM,
@ -553,6 +554,80 @@ static void wl1271_rx_streaming_timer(unsigned long data)
ieee80211_queue_work(wl->hw, &wlvif->rx_streaming_disable_work);
}
/* wl->mutex must be taken */
void wl12xx_rearm_tx_watchdog_locked(struct wl1271 *wl)
{
/* if the watchdog is not armed, don't do anything */
if (wl->tx_allocated_blocks == 0)
return;
cancel_delayed_work(&wl->tx_watchdog_work);
ieee80211_queue_delayed_work(wl->hw, &wl->tx_watchdog_work,
msecs_to_jiffies(wl->conf.tx.tx_watchdog_timeout));
}
static void wl12xx_tx_watchdog_work(struct work_struct *work)
{
struct delayed_work *dwork;
struct wl1271 *wl;
dwork = container_of(work, struct delayed_work, work);
wl = container_of(dwork, struct wl1271, tx_watchdog_work);
mutex_lock(&wl->mutex);
if (unlikely(wl->state == WL1271_STATE_OFF))
goto out;
/* Tx went out in the meantime - everything is ok */
if (unlikely(wl->tx_allocated_blocks == 0))
goto out;
/*
* if a ROC is in progress, we might not have any Tx for a long
* time (e.g. pending Tx on the non-ROC channels)
*/
if (find_first_bit(wl->roc_map, WL12XX_MAX_ROLES) < WL12XX_MAX_ROLES) {
wl1271_debug(DEBUG_TX, "No Tx (in FW) for %d ms due to ROC",
wl->conf.tx.tx_watchdog_timeout);
wl12xx_rearm_tx_watchdog_locked(wl);
goto out;
}
/*
* if a scan is in progress, we might not have any Tx for a long
* time
*/
if (wl->scan.state != WL1271_SCAN_STATE_IDLE) {
wl1271_debug(DEBUG_TX, "No Tx (in FW) for %d ms due to scan",
wl->conf.tx.tx_watchdog_timeout);
wl12xx_rearm_tx_watchdog_locked(wl);
goto out;
}
/*
* AP might cache a frame for a long time for a sleeping station,
* so rearm the timer if there's an AP interface with stations. If
* Tx is genuinely stuck we will most hopefully discover it when all
* stations are removed due to inactivity.
*/
if (wl->active_sta_count) {
wl1271_debug(DEBUG_TX, "No Tx (in FW) for %d ms. AP has "
" %d stations",
wl->conf.tx.tx_watchdog_timeout,
wl->active_sta_count);
wl12xx_rearm_tx_watchdog_locked(wl);
goto out;
}
wl1271_error("Tx stuck (in FW) for %d ms. Starting recovery",
wl->conf.tx.tx_watchdog_timeout);
wl12xx_queue_recovery_work(wl);
out:
mutex_unlock(&wl->mutex);
}
static void wl1271_conf_init(struct wl1271 *wl)
{
@ -745,6 +820,18 @@ static void wl12xx_fw_status(struct wl1271 *wl,
wl->tx_allocated_blocks -= freed_blocks;
/*
* If the FW freed some blocks:
* If we still have allocated blocks - re-arm the timer, Tx is
* not stuck. Otherwise, cancel the timer (no Tx currently).
*/
if (freed_blocks) {
if (wl->tx_allocated_blocks)
wl12xx_rearm_tx_watchdog_locked(wl);
else
cancel_delayed_work(&wl->tx_watchdog_work);
}
avail = le32_to_cpu(status->tx_total) - wl->tx_allocated_blocks;
/*
@ -1418,6 +1505,7 @@ int wl1271_plt_stop(struct wl1271 *wl)
cancel_work_sync(&wl->netstack_work);
cancel_work_sync(&wl->recovery_work);
cancel_delayed_work_sync(&wl->elp_work);
cancel_delayed_work_sync(&wl->tx_watchdog_work);
mutex_lock(&wl->mutex);
wl1271_power_off(wl);
@ -1789,6 +1877,7 @@ static void wl1271_op_stop(struct ieee80211_hw *hw)
cancel_work_sync(&wl->netstack_work);
cancel_work_sync(&wl->tx_work);
cancel_delayed_work_sync(&wl->elp_work);
cancel_delayed_work_sync(&wl->tx_watchdog_work);
/* let's notify MAC80211 about the remaining pending TX frames */
wl12xx_tx_reset(wl, true);
@ -2218,6 +2307,12 @@ static void __wl1271_op_remove_interface(struct wl1271 *wl,
if (wl->scan.state != WL1271_SCAN_STATE_IDLE &&
wl->scan_vif == vif) {
/*
* Rearm the tx watchdog just before idling scan. This
* prevents just-finished scans from triggering the watchdog
*/
wl12xx_rearm_tx_watchdog_locked(wl);
wl->scan.state = WL1271_SCAN_STATE_IDLE;
memset(wl->scan.scanned_ch, 0, sizeof(wl->scan.scanned_ch));
wl->scan_vif = NULL;
@ -3129,6 +3224,13 @@ static void wl1271_op_cancel_hw_scan(struct ieee80211_hw *hw,
if (ret < 0)
goto out_sleep;
}
/*
* Rearm the tx watchdog just before idling scan. This
* prevents just-finished scans from triggering the watchdog
*/
wl12xx_rearm_tx_watchdog_locked(wl);
wl->scan.state = WL1271_SCAN_STATE_IDLE;
memset(wl->scan.scanned_ch, 0, sizeof(wl->scan.scanned_ch));
wl->scan_vif = NULL;
@ -4138,6 +4240,13 @@ void wl1271_free_sta(struct wl1271 *wl, struct wl12xx_vif *wlvif, u8 hlid)
__clear_bit(hlid, (unsigned long *)&wl->ap_fw_ps_map);
wl12xx_free_link(wl, wlvif, &hlid);
wl->active_sta_count--;
/*
* rearm the tx watchdog when the last STA is freed - give the FW a
* chance to return STA-buffered packets before complaining.
*/
if (wl->active_sta_count == 0)
wl12xx_rearm_tx_watchdog_locked(wl);
}
static int wl12xx_sta_add(struct wl1271 *wl,
@ -5212,6 +5321,7 @@ static struct ieee80211_hw *wl1271_alloc_hw(void)
INIT_WORK(&wl->tx_work, wl1271_tx_work);
INIT_WORK(&wl->recovery_work, wl1271_recovery_work);
INIT_DELAYED_WORK(&wl->scan_complete_work, wl1271_scan_complete_work);
INIT_DELAYED_WORK(&wl->tx_watchdog_work, wl12xx_tx_watchdog_work);
wl->freezable_wq = create_freezable_workqueue("wl12xx_wq");
if (!wl->freezable_wq) {

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@ -55,6 +55,12 @@ void wl1271_scan_complete_work(struct work_struct *work)
vif = wl->scan_vif;
wlvif = wl12xx_vif_to_data(vif);
/*
* Rearm the tx watchdog just before idling scan. This
* prevents just-finished scans from triggering the watchdog
*/
wl12xx_rearm_tx_watchdog_locked(wl);
wl->scan.state = WL1271_SCAN_STATE_IDLE;
memset(wl->scan.scanned_ch, 0, sizeof(wl->scan.scanned_ch));
wl->scan.req = NULL;

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@ -226,6 +226,10 @@ static int wl1271_tx_allocate(struct wl1271 *wl, struct wl12xx_vif *wlvif,
wl->tx_blocks_available -= total_blocks;
wl->tx_allocated_blocks += total_blocks;
/* If the FW was empty before, arm the Tx watchdog */
if (wl->tx_allocated_blocks == total_blocks)
wl12xx_rearm_tx_watchdog_locked(wl);
ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
wl->tx_allocated_pkts[ac]++;

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@ -227,5 +227,6 @@ void wl12xx_rearm_rx_streaming(struct wl1271 *wl, unsigned long *active_hlids);
/* from main.c */
void wl1271_free_sta(struct wl1271 *wl, struct wl12xx_vif *wlvif, u8 hlid);
void wl12xx_rearm_tx_watchdog_locked(struct wl1271 *wl);
#endif

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@ -495,6 +495,9 @@ struct wl1271 {
/* last wlvif we transmitted from */
struct wl12xx_vif *last_wlvif;
/* work to fire when Tx is stuck */
struct delayed_work tx_watchdog_work;
};
struct wl1271_station {