b43legacy: Remove unnecessary MMIO in interrupt hotpath
This removes unnecessary MMIO accesses in the interrupt hotpath. The
patch by Michael Buesch for b43 has been ported to b43legacy.
Signed-off-by: Stefano Brivio <stefano.brivio@polimi.it>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/b43legacy/main.c b/drivers/net/wireless/b43legacy/main.c
index 07c7898..0062b34 100644
--- a/drivers/net/wireless/b43legacy/main.c
+++ b/drivers/net/wireless/b43legacy/main.c
@@ -583,35 +583,6 @@
b43legacy_set_slot_time(dev, 20);
}
-/* Enable a Generic IRQ. "mask" is the mask of which IRQs to enable.
- * Returns the _previously_ enabled IRQ mask.
- */
-static inline u32 b43legacy_interrupt_enable(struct b43legacy_wldev *dev,
- u32 mask)
-{
- u32 old_mask;
-
- old_mask = b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_MASK);
- b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, old_mask |
- mask);
-
- return old_mask;
-}
-
-/* Disable a Generic IRQ. "mask" is the mask of which IRQs to disable.
- * Returns the _previously_ enabled IRQ mask.
- */
-static inline u32 b43legacy_interrupt_disable(struct b43legacy_wldev *dev,
- u32 mask)
-{
- u32 old_mask;
-
- old_mask = b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_MASK);
- b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, old_mask & ~mask);
-
- return old_mask;
-}
-
/* Synchronize IRQ top- and bottom-half.
* IRQs must be masked before calling this.
* This must not be called with the irq_lock held.
@@ -1200,7 +1171,7 @@
/* This is the bottom half of the asynchronous beacon update. */
/* Ignore interrupt in the future. */
- dev->irq_savedstate &= ~B43legacy_IRQ_BEACON;
+ dev->irq_mask &= ~B43legacy_IRQ_BEACON;
cmd = b43legacy_read32(dev, B43legacy_MMIO_MACCMD);
beacon0_valid = (cmd & B43legacy_MACCMD_BEACON0_VALID);
@@ -1209,7 +1180,7 @@
/* Schedule interrupt manually, if busy. */
if (beacon0_valid && beacon1_valid) {
b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_REASON, B43legacy_IRQ_BEACON);
- dev->irq_savedstate |= B43legacy_IRQ_BEACON;
+ dev->irq_mask |= B43legacy_IRQ_BEACON;
return;
}
@@ -1247,12 +1218,11 @@
dev = wl->current_dev;
if (likely(dev && (b43legacy_status(dev) >= B43legacy_STAT_INITIALIZED))) {
spin_lock_irq(&wl->irq_lock);
- /* update beacon right away or defer to irq */
- dev->irq_savedstate = b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_MASK);
+ /* Update beacon right away or defer to IRQ. */
handle_irq_beacon(dev);
/* The handler might have updated the IRQ mask. */
b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK,
- dev->irq_savedstate);
+ dev->irq_mask);
mmiowb();
spin_unlock_irq(&wl->irq_lock);
}
@@ -1398,7 +1368,7 @@
if (reason & B43legacy_IRQ_TX_OK)
handle_irq_transmit_status(dev);
- b43legacy_interrupt_enable(dev, dev->irq_savedstate);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, dev->irq_mask);
mmiowb();
spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
}
@@ -1450,18 +1420,18 @@
struct b43legacy_wldev *dev = dev_id;
u32 reason;
- if (!dev)
- return IRQ_NONE;
+ B43legacy_WARN_ON(!dev);
spin_lock(&dev->wl->irq_lock);
- if (b43legacy_status(dev) < B43legacy_STAT_STARTED)
+ if (unlikely(b43legacy_status(dev) < B43legacy_STAT_STARTED))
+ /* This can only happen on shared IRQ lines. */
goto out;
reason = b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_REASON);
if (reason == 0xffffffff) /* shared IRQ */
goto out;
ret = IRQ_HANDLED;
- reason &= b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_MASK);
+ reason &= dev->irq_mask;
if (!reason)
goto out;
@@ -1485,10 +1455,9 @@
& 0x0000DC00;
b43legacy_interrupt_ack(dev, reason);
- /* disable all IRQs. They are enabled again in the bottom half. */
- dev->irq_savedstate = b43legacy_interrupt_disable(dev,
- B43legacy_IRQ_ALL);
- /* save the reason code and call our bottom half. */
+ /* Disable all IRQs. They are enabled again in the bottom half. */
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, 0);
+ /* Save the reason code and call our bottom half. */
dev->irq_reason = reason;
tasklet_schedule(&dev->isr_tasklet);
out:
@@ -1948,7 +1917,8 @@
/* Re-enable IRQs. */
spin_lock_irq(&dev->wl->irq_lock);
- b43legacy_interrupt_enable(dev, dev->irq_savedstate);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK,
+ dev->irq_mask);
spin_unlock_irq(&dev->wl->irq_lock);
}
}
@@ -1967,10 +1937,9 @@
/* Mask IRQs before suspending MAC. Otherwise
* the MAC stays busy and won't suspend. */
spin_lock_irq(&dev->wl->irq_lock);
- tmp = b43legacy_interrupt_disable(dev, B43legacy_IRQ_ALL);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, 0);
spin_unlock_irq(&dev->wl->irq_lock);
b43legacy_synchronize_irq(dev);
- dev->irq_savedstate = tmp;
b43legacy_power_saving_ctl_bits(dev, -1, 1);
b43legacy_write32(dev, B43legacy_MMIO_MACCTL,
@@ -2659,7 +2628,6 @@
int antenna_tx;
int antenna_rx;
int err = 0;
- u32 savedirqs;
antenna_tx = B43legacy_ANTENNA_DEFAULT;
antenna_rx = B43legacy_ANTENNA_DEFAULT;
@@ -2699,7 +2667,7 @@
spin_unlock_irqrestore(&wl->irq_lock, flags);
goto out_unlock_mutex;
}
- savedirqs = b43legacy_interrupt_disable(dev, B43legacy_IRQ_ALL);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, 0);
spin_unlock_irqrestore(&wl->irq_lock, flags);
b43legacy_synchronize_irq(dev);
@@ -2738,7 +2706,7 @@
}
spin_lock_irqsave(&wl->irq_lock, flags);
- b43legacy_interrupt_enable(dev, savedirqs);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, dev->irq_mask);
mmiowb();
spin_unlock_irqrestore(&wl->irq_lock, flags);
out_unlock_mutex:
@@ -2801,7 +2769,6 @@
struct b43legacy_wldev *dev;
struct b43legacy_phy *phy;
unsigned long flags;
- u32 savedirqs;
mutex_lock(&wl->mutex);
B43legacy_WARN_ON(wl->vif != vif);
@@ -2817,7 +2784,7 @@
spin_unlock_irqrestore(&wl->irq_lock, flags);
goto out_unlock_mutex;
}
- savedirqs = b43legacy_interrupt_disable(dev, B43legacy_IRQ_ALL);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, 0);
if (changed & BSS_CHANGED_BSSID) {
spin_unlock_irqrestore(&wl->irq_lock, flags);
@@ -2862,7 +2829,7 @@
b43legacy_mac_enable(dev);
spin_lock_irqsave(&wl->irq_lock, flags);
- b43legacy_interrupt_enable(dev, savedirqs);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, dev->irq_mask);
/* XXX: why? */
mmiowb();
spin_unlock_irqrestore(&wl->irq_lock, flags);
@@ -2922,8 +2889,7 @@
* setting the status to INITIALIZED, as the interrupt handler
* won't care about IRQs then. */
spin_lock_irqsave(&wl->irq_lock, flags);
- dev->irq_savedstate = b43legacy_interrupt_disable(dev,
- B43legacy_IRQ_ALL);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, 0);
b43legacy_read32(dev, B43legacy_MMIO_GEN_IRQ_MASK); /* flush */
spin_unlock_irqrestore(&wl->irq_lock, flags);
b43legacy_synchronize_irq(dev);
@@ -2963,7 +2929,7 @@
/* Start data flow (TX/RX) */
b43legacy_mac_enable(dev);
- b43legacy_interrupt_enable(dev, dev->irq_savedstate);
+ b43legacy_write32(dev, B43legacy_MMIO_GEN_IRQ_MASK, dev->irq_mask);
/* Start maintenance work */
b43legacy_periodic_tasks_setup(dev);
@@ -3126,7 +3092,7 @@
/* IRQ related flags */
dev->irq_reason = 0;
memset(dev->dma_reason, 0, sizeof(dev->dma_reason));
- dev->irq_savedstate = B43legacy_IRQ_MASKTEMPLATE;
+ dev->irq_mask = B43legacy_IRQ_MASKTEMPLATE;
dev->mac_suspended = 1;