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rt2x00: Convert rt61pci to use tasklets 

Fix interrupt processing on slow machines by using individual tasklets
for each different device interrupt. This ensures that while a RX or TX
status tasklet is scheduled only the according device interrupt is
masked and other interrupts such as TBTT can still be processed.

Also, this allows us to use tasklet_hi_schedule for TBTT processing
which is required to not send out beacons with a wrong DTIM count (due
to delayed periodic beacon updates). Furthermore, this improves the
latency between the TBTT and sending out buffered multi- and broadcast
traffic.

As a nice bonus, the interrupt handling overhead should be much lower.

Compile-tested only.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Helmut Schaa 2011-01-30 13:19:08 +01:00 committed by John W. Linville
parent a9d61e9e77
commit 5846a550b5
1 changed files with 136 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

187
drivers/net/wireless/rt2x00/rt61pci.c
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@ -1142,6 +1142,11 @@ static void rt61pci_start_queue(struct data_queue *queue)
rt2x00pci_register_write(rt2x00dev, TXRX_CSR0, reg);
break;
case QID_BEACON:
/*
* Allow the tbtt tasklet to be scheduled.
*/
tasklet_enable(&rt2x00dev->tbtt_tasklet);
rt2x00pci_register_read(rt2x00dev, TXRX_CSR9, &reg);
rt2x00_set_field32(&reg, TXRX_CSR9_TSF_TICKING, 1);
rt2x00_set_field32(&reg, TXRX_CSR9_TBTT_ENABLE, 1);
@ -1221,6 +1226,11 @@ static void rt61pci_stop_queue(struct data_queue *queue)
rt2x00_set_field32(&reg, TXRX_CSR9_TBTT_ENABLE, 0);
rt2x00_set_field32(&reg, TXRX_CSR9_BEACON_GEN, 0);
rt2x00pci_register_write(rt2x00dev, TXRX_CSR9, reg);
/*
* Wait for possibly running tbtt tasklets.
*/
tasklet_disable(&rt2x00dev->tbtt_tasklet);
break;
default:
break;
@ -1710,6 +1720,7 @@ static void rt61pci_toggle_irq(struct rt2x00_dev *rt2x00dev,
int mask = (state == STATE_RADIO_IRQ_OFF) ||
(state == STATE_RADIO_IRQ_OFF_ISR);
u32 reg;
unsigned long flags;
/*
* When interrupts are being enabled, the interrupt registers
@ -1721,12 +1732,21 @@ static void rt61pci_toggle_irq(struct rt2x00_dev *rt2x00dev,
rt2x00pci_register_read(rt2x00dev, MCU_INT_SOURCE_CSR, &reg);
rt2x00pci_register_write(rt2x00dev, MCU_INT_SOURCE_CSR, reg);
/*
* Enable tasklets.
*/
tasklet_enable(&rt2x00dev->txstatus_tasklet);
tasklet_enable(&rt2x00dev->rxdone_tasklet);
tasklet_enable(&rt2x00dev->autowake_tasklet);
}
/*
* Only toggle the interrupts bits we are going to use.
* Non-checked interrupt bits are disabled by default.
*/
spin_lock_irqsave(&rt2x00dev->irqmask_lock, flags);
rt2x00pci_register_read(rt2x00dev, INT_MASK_CSR, &reg);
rt2x00_set_field32(&reg, INT_MASK_CSR_TXDONE, mask);
rt2x00_set_field32(&reg, INT_MASK_CSR_RXDONE, mask);
@ -1746,6 +1766,17 @@ static void rt61pci_toggle_irq(struct rt2x00_dev *rt2x00dev,
rt2x00_set_field32(&reg, MCU_INT_MASK_CSR_7, mask);
rt2x00_set_field32(&reg, MCU_INT_MASK_CSR_TWAKEUP, mask);
rt2x00pci_register_write(rt2x00dev, MCU_INT_MASK_CSR, reg);
spin_unlock_irqrestore(&rt2x00dev->irqmask_lock, flags);
if (state == STATE_RADIO_IRQ_OFF) {
/*
* Ensure that all tasklets are finished.
*/
tasklet_disable(&rt2x00dev->txstatus_tasklet);
tasklet_disable(&rt2x00dev->rxdone_tasklet);
tasklet_disable(&rt2x00dev->autowake_tasklet);
}
}
static int rt61pci_enable_radio(struct rt2x00_dev *rt2x00dev)
@ -2223,61 +2254,80 @@ static void rt61pci_wakeup(struct rt2x00_dev *rt2x00dev)
rt61pci_config(rt2x00dev, &libconf, IEEE80211_CONF_CHANGE_PS);
}
static irqreturn_t rt61pci_interrupt_thread(int irq, void *dev_instance)
static void rt61pci_enable_interrupt(struct rt2x00_dev *rt2x00dev,
struct rt2x00_field32 irq_field)
{
struct rt2x00_dev *rt2x00dev = dev_instance;
u32 reg = rt2x00dev->irqvalue[0];
u32 reg_mcu = rt2x00dev->irqvalue[1];
unsigned long flags;
u32 reg;
/*
* Handle interrupts, walk through all bits
* and run the tasks, the bits are checked in order of
* priority.
* Enable a single interrupt. The interrupt mask register
* access needs locking.
*/
spin_lock_irqsave(&rt2x00dev->irqmask_lock, flags);
/*
* 1 - Rx ring done interrupt.
*/
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_RXDONE))
rt2x00pci_rxdone(rt2x00dev);
rt2x00pci_register_read(rt2x00dev, INT_MASK_CSR, &reg);
rt2x00_set_field32(&reg, irq_field, 0);
rt2x00pci_register_write(rt2x00dev, INT_MASK_CSR, reg);
/*
* 2 - Tx ring done interrupt.
*/
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_TXDONE))
rt61pci_txdone(rt2x00dev);
/*
* 3 - Handle MCU command done.
*/
if (reg_mcu)
rt2x00pci_register_write(rt2x00dev,
M2H_CMD_DONE_CSR, 0xffffffff);
/*
* 4 - MCU Autowakeup interrupt.
*/
if (rt2x00_get_field32(reg_mcu, MCU_INT_SOURCE_CSR_TWAKEUP))
rt61pci_wakeup(rt2x00dev);
/*
* 5 - Beacon done interrupt.
*/
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_BEACON_DONE))
rt2x00lib_beacondone(rt2x00dev);
/* Enable interrupts again. */
rt2x00dev->ops->lib->set_device_state(rt2x00dev,
STATE_RADIO_IRQ_ON_ISR);
return IRQ_HANDLED;
spin_unlock_irqrestore(&rt2x00dev->irqmask_lock, flags);
}
static void rt61pci_enable_mcu_interrupt(struct rt2x00_dev *rt2x00dev,
struct rt2x00_field32 irq_field)
{
unsigned long flags;
u32 reg;
/*
* Enable a single MCU interrupt. The interrupt mask register
* access needs locking.
*/
spin_lock_irqsave(&rt2x00dev->irqmask_lock, flags);
rt2x00pci_register_read(rt2x00dev, MCU_INT_MASK_CSR, &reg);
rt2x00_set_field32(&reg, irq_field, 0);
rt2x00pci_register_write(rt2x00dev, MCU_INT_MASK_CSR, reg);
spin_unlock_irqrestore(&rt2x00dev->irqmask_lock, flags);
}
static void rt61pci_txstatus_tasklet(unsigned long data)
{
struct rt2x00_dev *rt2x00dev = (struct rt2x00_dev *)data;
rt61pci_txdone(rt2x00dev);
rt61pci_enable_interrupt(rt2x00dev, INT_MASK_CSR_TXDONE);
}
static void rt61pci_tbtt_tasklet(unsigned long data)
{
struct rt2x00_dev *rt2x00dev = (struct rt2x00_dev *)data;
rt2x00lib_beacondone(rt2x00dev);
rt61pci_enable_interrupt(rt2x00dev, INT_MASK_CSR_BEACON_DONE);
}
static void rt61pci_rxdone_tasklet(unsigned long data)
{
struct rt2x00_dev *rt2x00dev = (struct rt2x00_dev *)data;
rt2x00pci_rxdone(rt2x00dev);
rt61pci_enable_interrupt(rt2x00dev, INT_MASK_CSR_RXDONE);
}
static void rt61pci_autowake_tasklet(unsigned long data)
{
struct rt2x00_dev *rt2x00dev = (struct rt2x00_dev *)data;
rt61pci_wakeup(rt2x00dev);
rt2x00pci_register_write(rt2x00dev,
M2H_CMD_DONE_CSR, 0xffffffff);
rt61pci_enable_mcu_interrupt(rt2x00dev, MCU_INT_MASK_CSR_TWAKEUP);
}
static irqreturn_t rt61pci_interrupt(int irq, void *dev_instance)
{
struct rt2x00_dev *rt2x00dev = dev_instance;
u32 reg_mcu;
u32 reg;
u32 reg_mcu, mask_mcu;
u32 reg, mask;
unsigned long flags;
/*
* Get the interrupt sources & saved to local variable.
@ -2295,14 +2345,46 @@ static irqreturn_t rt61pci_interrupt(int irq, void *dev_instance)
if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags))
return IRQ_HANDLED;
/* Store irqvalues for use in the interrupt thread. */
rt2x00dev->irqvalue[0] = reg;
rt2x00dev->irqvalue[1] = reg_mcu;
/*
* Schedule tasklets for interrupt handling.
*/
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_RXDONE))
tasklet_schedule(&rt2x00dev->rxdone_tasklet);
/* Disable interrupts, will be enabled again in the interrupt thread. */
rt2x00dev->ops->lib->set_device_state(rt2x00dev,
STATE_RADIO_IRQ_OFF_ISR);
return IRQ_WAKE_THREAD;
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_TXDONE))
tasklet_schedule(&rt2x00dev->txstatus_tasklet);
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_BEACON_DONE))
tasklet_hi_schedule(&rt2x00dev->tbtt_tasklet);
if (rt2x00_get_field32(reg_mcu, MCU_INT_SOURCE_CSR_TWAKEUP))
tasklet_schedule(&rt2x00dev->autowake_tasklet);
/*
* Since INT_MASK_CSR and INT_SOURCE_CSR use the same bits
* for interrupts and interrupt masks we can just use the value of
* INT_SOURCE_CSR to create the interrupt mask.
*/
mask = reg;
mask_mcu = reg_mcu;
/*
* Disable all interrupts for which a tasklet was scheduled right now,
* the tasklet will reenable the appropriate interrupts.
*/
spin_lock_irqsave(&rt2x00dev->irqmask_lock, flags);
rt2x00pci_register_read(rt2x00dev, INT_MASK_CSR, &reg);
reg |= mask;
rt2x00pci_register_write(rt2x00dev, INT_MASK_CSR, reg);
rt2x00pci_register_read(rt2x00dev, MCU_INT_MASK_CSR, &reg);
reg |= mask_mcu;
rt2x00pci_register_write(rt2x00dev, MCU_INT_MASK_CSR, reg);
spin_unlock_irqrestore(&rt2x00dev->irqmask_lock, flags);
return IRQ_HANDLED;
}
/*
@ -2896,7 +2978,10 @@ static const struct ieee80211_ops rt61pci_mac80211_ops = {
static const struct rt2x00lib_ops rt61pci_rt2x00_ops = {
.irq_handler = rt61pci_interrupt,
.irq_handler_thread = rt61pci_interrupt_thread,
.txstatus_tasklet = rt61pci_txstatus_tasklet,
.tbtt_tasklet = rt61pci_tbtt_tasklet,
.rxdone_tasklet = rt61pci_rxdone_tasklet,
.autowake_tasklet = rt61pci_autowake_tasklet,
.probe_hw = rt61pci_probe_hw,
.get_firmware_name = rt61pci_get_firmware_name,
.check_firmware = rt61pci_check_firmware,