Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-29 22:31:32 +00:00
Code Issues Packages Projects Releases Wiki Activity

ath9k: fix stopping tx dma on reset

Browse Source 
In some situations, stopping Tx DMA frequently fails, leading to messages
like this:

ath: Failed to stop TX DMA in 100 msec after killing last frame
ath: Failed to stop TX DMA!

This patch uses a few MAC features to abort DMA globally instead of iterating
over all hardware queues and attempting to stop them individually.
Not only is that faster and works with a shorter timeout, it also makes the
process much more reliable.

With this change, I can no longer trigger these messages on AR9380,
and on AR9280 they become much more rare.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Felix Fietkau 2011-03-11 21:38:18 +01:00 committed by John W. Linville
parent 997941d7ef
commit 0d51cccc24
3 changed files with 35 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
drivers/net/wireless/ath/ath9k/mac.c
View File

@ -143,6 +143,34 @@ bool ath9k_hw_updatetxtriglevel(struct ath_hw *ah, bool bIncTrigLevel)
}
EXPORT_SYMBOL(ath9k_hw_updatetxtriglevel);
void ath9k_hw_abort_tx_dma(struct ath_hw *ah)
{
int i, q;
REG_WRITE(ah, AR_Q_TXD, AR_Q_TXD_M);
REG_SET_BIT(ah, AR_PCU_MISC, AR_PCU_FORCE_QUIET_COLL | AR_PCU_CLEAR_VMF);
REG_SET_BIT(ah, AR_DIAG_SW, AR_DIAG_FORCE_CH_IDLE_HIGH);
REG_SET_BIT(ah, AR_D_GBL_IFS_MISC, AR_D_GBL_IFS_MISC_IGNORE_BACKOFF);
for (q = 0; q < AR_NUM_QCU; q++) {
for (i = 0; i < 1000; i++) {
if (i)
udelay(5);
if (!ath9k_hw_numtxpending(ah, q))
break;
}
}
REG_CLR_BIT(ah, AR_PCU_MISC, AR_PCU_FORCE_QUIET_COLL | AR_PCU_CLEAR_VMF);
REG_CLR_BIT(ah, AR_DIAG_SW, AR_DIAG_FORCE_CH_IDLE_HIGH);
REG_CLR_BIT(ah, AR_D_GBL_IFS_MISC, AR_D_GBL_IFS_MISC_IGNORE_BACKOFF);
REG_WRITE(ah, AR_Q_TXD, 0);
}
EXPORT_SYMBOL(ath9k_hw_abort_tx_dma);
bool ath9k_hw_stoptxdma(struct ath_hw *ah, u32 q)
{
#define ATH9K_TX_STOP_DMA_TIMEOUT 4000 /* usec */

1
drivers/net/wireless/ath/ath9k/mac.h
View File

@ -677,6 +677,7 @@ void ath9k_hw_cleartxdesc(struct ath_hw *ah, void *ds);
u32 ath9k_hw_numtxpending(struct ath_hw *ah, u32 q);
bool ath9k_hw_updatetxtriglevel(struct ath_hw *ah, bool bIncTrigLevel);
bool ath9k_hw_stoptxdma(struct ath_hw *ah, u32 q);
void ath9k_hw_abort_tx_dma(struct ath_hw *ah);
void ath9k_hw_gettxintrtxqs(struct ath_hw *ah, u32 *txqs);
bool ath9k_hw_set_txq_props(struct ath_hw *ah, int q,
const struct ath9k_tx_queue_info *qinfo);

14
drivers/net/wireless/ath/ath9k/xmit.c
View File

@ -1194,16 +1194,14 @@ bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
if (sc->sc_flags & SC_OP_INVALID)
return true;
/* Stop beacon queue */
ath9k_hw_stoptxdma(sc->sc_ah, sc->beacon.beaconq);
ath9k_hw_abort_tx_dma(ah);
/* Stop data queues */
/* Check if any queue remains active */
for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
if (ATH_TXQ_SETUP(sc, i)) {
txq = &sc->tx.txq[i];
ath9k_hw_stoptxdma(ah, txq->axq_qnum);
npend += ath9k_hw_numtxpending(ah, txq->axq_qnum);
}
if (!ATH_TXQ_SETUP(sc, i))
continue;
npend += ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum);
}
if (npend)