Same devices can generate interrupt without properly setting bit in INT_SOURCE_CSR register (spurious interrupt), what will cause IRQ line will be disabled by interrupts controller driver. We discovered that clearing INT_MASK_CSR stops such behaviour. We previously first read that register, and then clear all know interrupt sources bits and do not touch reserved bits. After this patch, we write to all register content (I believe writing to reserved bits on that register will not cause any problems, I tested that on my rt2800pci device). This fix very bad performance problem, practically making device unusable (since worked without interrupts), reported in: https://bugzilla.redhat.com/show_bug.cgi?id=658451 We previously tried to workaround that issue in commit 4ba7d9997869d25bd223dea7536fc1ce9fab3b3b "rt2800pci: handle spurious interrupts", but it was reverted in commit 82e5fc2a34fa9ffea38f00c4066b7e600a0ca5e6 as thing, that will prevent to detect real spurious interrupts. Reported-and-tested-by: Amir Hedayaty <hedayaty@xxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Stanislaw Gruszka <sgruszka@xxxxxxxxxx> --- drivers/net/wireless/rt2x00/rt2800pci.c | 28 ++++++++-------------------- 1 files changed, 8 insertions(+), 20 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2800pci.c b/drivers/net/wireless/rt2x00/rt2800pci.c index 4941a1a..dc88bae 100644 --- a/drivers/net/wireless/rt2x00/rt2800pci.c +++ b/drivers/net/wireless/rt2x00/rt2800pci.c @@ -422,7 +422,6 @@ static int rt2800pci_init_queues(struct rt2x00_dev *rt2x00dev) static void rt2800pci_toggle_irq(struct rt2x00_dev *rt2x00dev, enum dev_state state) { - int mask = (state == STATE_RADIO_IRQ_ON); u32 reg; unsigned long flags; @@ -436,25 +435,14 @@ static void rt2800pci_toggle_irq(struct rt2x00_dev *rt2x00dev, } spin_lock_irqsave(&rt2x00dev->irqmask_lock, flags); - rt2x00pci_register_read(rt2x00dev, INT_MASK_CSR, ®); - rt2x00_set_field32(®, INT_MASK_CSR_RXDELAYINT, 0); - rt2x00_set_field32(®, INT_MASK_CSR_TXDELAYINT, 0); - rt2x00_set_field32(®, INT_MASK_CSR_RX_DONE, mask); - rt2x00_set_field32(®, INT_MASK_CSR_AC0_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_AC1_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_AC2_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_AC3_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_HCCA_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_MGMT_DMA_DONE, 0); - rt2x00_set_field32(®, INT_MASK_CSR_MCU_COMMAND, 0); - rt2x00_set_field32(®, INT_MASK_CSR_RXTX_COHERENT, 0); - rt2x00_set_field32(®, INT_MASK_CSR_TBTT, mask); - rt2x00_set_field32(®, INT_MASK_CSR_PRE_TBTT, mask); - rt2x00_set_field32(®, INT_MASK_CSR_TX_FIFO_STATUS, mask); - rt2x00_set_field32(®, INT_MASK_CSR_AUTO_WAKEUP, mask); - rt2x00_set_field32(®, INT_MASK_CSR_GPTIMER, 0); - rt2x00_set_field32(®, INT_MASK_CSR_RX_COHERENT, 0); - rt2x00_set_field32(®, INT_MASK_CSR_TX_COHERENT, 0); + reg = 0; + if (state == STATE_RADIO_IRQ_ON) { + rt2x00_set_field32(®, INT_MASK_CSR_RX_DONE, 1); + rt2x00_set_field32(®, INT_MASK_CSR_TBTT, 1); + rt2x00_set_field32(®, INT_MASK_CSR_PRE_TBTT, 1); + rt2x00_set_field32(®, INT_MASK_CSR_TX_FIFO_STATUS, 1); + rt2x00_set_field32(®, INT_MASK_CSR_AUTO_WAKEUP, 1); + } rt2x00pci_register_write(rt2x00dev, INT_MASK_CSR, reg); spin_unlock_irqrestore(&rt2x00dev->irqmask_lock, flags); -- 1.7.1 -- 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
