From: Stefano Brivio <stefano.brivio@xxxxxxxxx>
This removes unnecessary MMIO accesses in the interrupt hotpath. The
patch by Michael Buesch for b43 has been ported to b43legacy.
Signed-off-by: Michael Buesch <mb@xxxxxxxxx>
Signed-off-by: Stefano Brivio <stefano.brivio@xxxxxxxxx>
Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
---
John,
This is 2.6.31 material. I am submitting this for Stefano because
this patch touches a section of the code that had to be changed
to fix the locking problem addressed in Patch 2/2.
I hope this patch does not cause any problems. My normal method
is not available while I'm away from home.
Larry
---
Index: wireless-testing/drivers/net/wireless/b43legacy/b43legacy.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43legacy/b43legacy.h
+++ wireless-testing/drivers/net/wireless/b43legacy/b43legacy.h
@@ -694,8 +694,8 @@ struct b43legacy_wldev {
/* Reason code of the last interrupt. */
u32 irq_reason;
u32 dma_reason[6];
- /* saved irq enable/disable state bitfield. */
- u32 irq_savedstate;
+ /* The currently active generic-interrupt mask. */
+ u32 irq_mask;
/* Link Quality calculation context. */
struct b43legacy_noise_calculation noisecalc;
/* if > 0 MAC is suspended. if == 0 MAC is enabled. */
Index: wireless-testing/drivers/net/wireless/b43legacy/main.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43legacy/main.c
+++ wireless-testing/drivers/net/wireless/b43legacy/main.c
@@ -583,35 +583,6 @@ static void b43legacy_short_slot_timing_
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 @@ static void handle_irq_beacon(struct b43
/* 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 @@ static void handle_irq_beacon(struct b43
/* 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 @@ static void b43legacy_beacon_update_trig
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 @@ static void b43legacy_interrupt_tasklet(
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);
}
@@ -1431,16 +1401,18 @@ static void b43legacy_interrupt_ack(stru
b43legacy_write32(dev, B43legacy_MMIO_DMA0_REASON,
dev->dma_reason[0]);
- b43legacy_write32(dev, B43legacy_MMIO_DMA1_REASON,
- dev->dma_reason[1]);
- b43legacy_write32(dev, B43legacy_MMIO_DMA2_REASON,
- dev->dma_reason[2]);
- b43legacy_write32(dev, B43legacy_MMIO_DMA3_REASON,
- dev->dma_reason[3]);
- b43legacy_write32(dev, B43legacy_MMIO_DMA4_REASON,
- dev->dma_reason[4]);
- b43legacy_write32(dev, B43legacy_MMIO_DMA5_REASON,
- dev->dma_reason[5]);
+/* Unused rings.
+ * b43legacy_write32(dev, B43legacy_MMIO_DMA1_REASON,
+ * dev->dma_reason[1]);
+ * b43legacy_write32(dev, B43legacy_MMIO_DMA2_REASON,
+ * dev->dma_reason[2]);
+ * b43legacy_write32(dev, B43legacy_MMIO_DMA3_REASON,
+ * dev->dma_reason[3]);
+ * b43legacy_write32(dev, B43legacy_MMIO_DMA4_REASON,
+ * dev->dma_reason[4]);
+ * b43legacy_write32(dev, B43legacy_MMIO_DMA5_REASON,
+ * dev->dma_reason[5]);
+ */
}
/* Interrupt handler top-half */
@@ -1450,45 +1422,46 @@ static irqreturn_t b43legacy_interrupt_h
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;
dev->dma_reason[0] = b43legacy_read32(dev,
B43legacy_MMIO_DMA0_REASON)
& 0x0001DC00;
- dev->dma_reason[1] = b43legacy_read32(dev,
- B43legacy_MMIO_DMA1_REASON)
- & 0x0000DC00;
- dev->dma_reason[2] = b43legacy_read32(dev,
- B43legacy_MMIO_DMA2_REASON)
- & 0x0000DC00;
- dev->dma_reason[3] = b43legacy_read32(dev,
- B43legacy_MMIO_DMA3_REASON)
- & 0x0001DC00;
- dev->dma_reason[4] = b43legacy_read32(dev,
- B43legacy_MMIO_DMA4_REASON)
- & 0x0000DC00;
- dev->dma_reason[5] = b43legacy_read32(dev,
- B43legacy_MMIO_DMA5_REASON)
- & 0x0000DC00;
+/* Unused rings.
+ * dev->dma_reason[1] = b43legacy_read32(dev,
+ * B43legacy_MMIO_DMA1_REASON)
+ * & 0x0000DC00;
+ * dev->dma_reason[2] = b43legacy_read32(dev,
+ * B43legacy_MMIO_DMA2_REASON)
+ * & 0x0000DC00;
+ * dev->dma_reason[3] = b43legacy_read32(dev,
+ * B43legacy_MMIO_DMA3_REASON)
+ * & 0x0001DC00;
+ * dev->dma_reason[4] = b43legacy_read32(dev,
+ * B43legacy_MMIO_DMA4_REASON)
+ * & 0x0000DC00;
+ * dev->dma_reason[5] = b43legacy_read32(dev,
+ * B43legacy_MMIO_DMA5_REASON)
+ * & 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 +1921,8 @@ void b43legacy_mac_enable(struct b43lega
/* 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 +1941,9 @@ void b43legacy_mac_suspend(struct b43leg
/* 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 +2632,6 @@ static int b43legacy_op_dev_config(struc
int antenna_tx;
int antenna_rx;
int err = 0;
- u32 savedirqs;
antenna_tx = B43legacy_ANTENNA_DEFAULT;
antenna_rx = B43legacy_ANTENNA_DEFAULT;
@@ -2699,7 +2671,7 @@ static int b43legacy_op_dev_config(struc
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 +2710,7 @@ static int b43legacy_op_dev_config(struc
}
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 +2773,6 @@ static void b43legacy_op_bss_info_change
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 +2788,7 @@ static void b43legacy_op_bss_info_change
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 +2833,7 @@ static void b43legacy_op_bss_info_change
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 +2893,7 @@ static void b43legacy_wireless_core_stop
* 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 +2933,7 @@ static int b43legacy_wireless_core_start
/* 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 +3096,7 @@ static void setup_struct_wldev_for_init(
/* 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;
Index: wireless-testing/drivers/net/wireless/b43legacy/pio.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43legacy/pio.c
+++ wireless-testing/drivers/net/wireless/b43legacy/pio.c
@@ -443,7 +443,7 @@ int b43legacy_pio_init(struct b43legacy_
pio->queue3 = queue;
if (dev->dev->id.revision < 3)
- dev->irq_savedstate |= B43legacy_IRQ_PIO_WORKAROUND;
+ dev->irq_mask |= B43legacy_IRQ_PIO_WORKAROUND;
b43legacydbg(dev->wl, "PIO initialized\n");
err = 0;
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
