From 702a2f8430a28bf936f2891f34b57d5f965059bf Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 10 Apr 2011 16:23:39 +0000
Subject: [PATCH] ath5k: decrease interrupt load for rx/tx interrupts

SVN-Revision: 26579
---
 .../patches/470-ath5k_decrease_irq_load.patch | 140 ++++++++++++++++++
 1 file changed, 140 insertions(+)
 create mode 100644 package/mac80211/patches/470-ath5k_decrease_irq_load.patch

diff --git a/package/mac80211/patches/470-ath5k_decrease_irq_load.patch b/package/mac80211/patches/470-ath5k_decrease_irq_load.patch
new file mode 100644
index 0000000000..5273bb075a
--- /dev/null
+++ b/package/mac80211/patches/470-ath5k_decrease_irq_load.patch
@@ -0,0 +1,140 @@
+--- a/drivers/net/wireless/ath/ath5k/ath5k.h
++++ b/drivers/net/wireless/ath/ath5k/ath5k.h
+@@ -872,6 +872,19 @@ enum ath5k_int {
+ 	AR5K_INT_QTRIG	=	0x40000000, /* Non common */
+ 	AR5K_INT_GLOBAL =	0x80000000,
+ 
++	AR5K_INT_TX_ALL = AR5K_INT_TXOK
++		| AR5K_INT_TXDESC
++		| AR5K_INT_TXERR
++		| AR5K_INT_TXEOL
++		| AR5K_INT_TXURN,
++
++	AR5K_INT_RX_ALL = AR5K_INT_RXOK
++		| AR5K_INT_RXDESC
++		| AR5K_INT_RXERR
++		| AR5K_INT_RXNOFRM
++		| AR5K_INT_RXEOL
++		| AR5K_INT_RXORN,
++
+ 	AR5K_INT_COMMON  = AR5K_INT_RXOK
+ 		| AR5K_INT_RXDESC
+ 		| AR5K_INT_RXERR
+--- a/drivers/net/wireless/ath/ath5k/base.c
++++ b/drivers/net/wireless/ath/ath5k/base.c
+@@ -1444,6 +1444,21 @@ ath5k_receive_frame_ok(struct ath5k_soft
+ }
+ 
+ static void
++ath5k_set_current_imask(struct ath5k_softc *sc)
++{
++	enum ath5k_int imask = sc->imask;
++	unsigned long flags;
++
++	spin_lock_irqsave(&sc->irqlock, flags);
++	if (sc->rx_pending)
++		imask &= ~AR5K_INT_RX_ALL;
++	if (sc->tx_pending)
++		imask &= ~AR5K_INT_TX_ALL;
++	ath5k_hw_set_imr(sc->ah, imask);
++	spin_unlock_irqrestore(&sc->irqlock, flags);
++}
++
++static void
+ ath5k_tasklet_rx(unsigned long data)
+ {
+ 	struct ath5k_rx_status rs = {};
+@@ -1506,6 +1521,8 @@ next:
+ 	} while (ath5k_rxbuf_setup(sc, bf) == 0);
+ unlock:
+ 	spin_unlock(&sc->rxbuflock);
++	sc->rx_pending = false;
++	ath5k_set_current_imask(sc);
+ }
+ 
+ 
+@@ -1693,6 +1710,9 @@ ath5k_tasklet_tx(unsigned long data)
+ 	for (i=0; i < AR5K_NUM_TX_QUEUES; i++)
+ 		if (sc->txqs[i].setup && (sc->ah->ah_txq_isr & BIT(i)))
+ 			ath5k_tx_processq(sc, &sc->txqs[i]);
++
++	sc->tx_pending = false;
++	ath5k_set_current_imask(sc);
+ }
+ 
+ 
+@@ -2122,6 +2142,20 @@ ath5k_intr_calibration_poll(struct ath5k
+ 	 * AR5K_REG_ENABLE_BITS(ah, AR5K_CR, AR5K_CR_SWI); */
+ }
+ 
++static void
++ath5k_schedule_rx(struct ath5k_softc *sc)
++{
++	sc->rx_pending = true;
++	tasklet_schedule(&sc->rxtq);
++}
++
++static void
++ath5k_schedule_tx(struct ath5k_softc *sc)
++{
++	sc->tx_pending = true;
++	tasklet_schedule(&sc->txtq);
++}
++
+ irqreturn_t
+ ath5k_intr(int irq, void *dev_id)
+ {
+@@ -2164,7 +2198,7 @@ ath5k_intr(int irq, void *dev_id)
+ 				ieee80211_queue_work(sc->hw, &sc->reset_work);
+ 			}
+ 			else
+-				tasklet_schedule(&sc->rxtq);
++				ath5k_schedule_rx(sc);
+ 		} else {
+ 			if (status & AR5K_INT_SWBA) {
+ 				tasklet_hi_schedule(&sc->beacontq);
+@@ -2182,10 +2216,10 @@ ath5k_intr(int irq, void *dev_id)
+ 				ath5k_hw_update_tx_triglevel(ah, true);
+ 			}
+ 			if (status & (AR5K_INT_RXOK | AR5K_INT_RXERR))
+-				tasklet_schedule(&sc->rxtq);
++				ath5k_schedule_rx(sc);
+ 			if (status & (AR5K_INT_TXOK | AR5K_INT_TXDESC
+ 					| AR5K_INT_TXERR | AR5K_INT_TXEOL))
+-				tasklet_schedule(&sc->txtq);
++				ath5k_schedule_tx(sc);
+ 			if (status & AR5K_INT_BMISS) {
+ 				/* TODO */
+ 			}
+@@ -2204,6 +2238,9 @@ ath5k_intr(int irq, void *dev_id)
+ 
+ 	} while (ath5k_hw_is_intr_pending(ah) && --counter > 0);
+ 
++	if (sc->rx_pending || sc->tx_pending)
++		ath5k_set_current_imask(sc);
++
+ 	if (unlikely(!counter))
+ 		ATH5K_WARN(sc, "too many interrupts, giving up for now\n");
+ 
+@@ -2575,6 +2612,8 @@ done:
+ 
+ static void stop_tasklets(struct ath5k_softc *sc)
+ {
++	sc->rx_pending = false;
++	sc->tx_pending = false;
+ 	tasklet_kill(&sc->rxtq);
+ 	tasklet_kill(&sc->txtq);
+ 	tasklet_kill(&sc->calib);
+--- a/drivers/net/wireless/ath/ath5k/base.h
++++ b/drivers/net/wireless/ath/ath5k/base.h
+@@ -207,6 +207,10 @@ struct ath5k_softc {
+ 
+ 	enum ath5k_int		imask;		/* interrupt mask copy */
+ 
++	spinlock_t		irqlock;
++	bool			rx_pending;	/* rx tasklet pending */
++	bool			tx_pending;	/* tx tasklet pending */
++
+ 	u8			lladdr[ETH_ALEN];
+ 	u8			bssidmask[ETH_ALEN];
+