diff options
author | Thommy Jakobsson <thommyj@gmail.com> | 2013-04-23 21:45:11 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-05-19 11:38:29 -0700 |
commit | 548ebaffd93a8a3d54ddccf89b126e10a3c2a81e (patch) | |
tree | ca577154883e492d4be0815f8faf5ad44e1aeca7 /drivers/net/wireless/b43/main.c | |
parent | ab08ba324788b122edc3e983d7b7083fa20d6bc4 (diff) |
B43: Handle DMA RX descriptor underrun
commit 73b82bf0bfbf58e6ff328d3726934370585f6e78 upstream.
Add handling of rx descriptor underflow. This fixes a fault that could
happen on slow machines, where data is received faster than the CPU can
handle. In such a case the device will use up all rx descriptors and
refuse to send any more data before confirming that it is ok. This
patch enables necessary interrupt to discover such a situation and will
handle them by dropping everything in the ring buffer.
Reviewed-by: Michael Buesch <m@bues.ch>
Signed-off-by: Thommy Jakobsson <thommyj@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/wireless/b43/main.c')
-rw-r--r-- | drivers/net/wireless/b43/main.c | 43 |
1 files changed, 18 insertions, 25 deletions
diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index 05682736e46..64b637a8b5b 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -1895,30 +1895,18 @@ static void b43_do_interrupt_thread(struct b43_wldev *dev) } } - if (unlikely(merged_dma_reason & (B43_DMAIRQ_FATALMASK | - B43_DMAIRQ_NONFATALMASK))) { - if (merged_dma_reason & B43_DMAIRQ_FATALMASK) { - b43err(dev->wl, "Fatal DMA error: " - "0x%08X, 0x%08X, 0x%08X, " - "0x%08X, 0x%08X, 0x%08X\n", - dma_reason[0], dma_reason[1], - dma_reason[2], dma_reason[3], - dma_reason[4], dma_reason[5]); - b43err(dev->wl, "This device does not support DMA " + if (unlikely(merged_dma_reason & (B43_DMAIRQ_FATALMASK))) { + b43err(dev->wl, + "Fatal DMA error: 0x%08X, 0x%08X, 0x%08X, 0x%08X, 0x%08X, 0x%08X\n", + dma_reason[0], dma_reason[1], + dma_reason[2], dma_reason[3], + dma_reason[4], dma_reason[5]); + b43err(dev->wl, "This device does not support DMA " "on your system. It will now be switched to PIO.\n"); - /* Fall back to PIO transfers if we get fatal DMA errors! */ - dev->use_pio = true; - b43_controller_restart(dev, "DMA error"); - return; - } - if (merged_dma_reason & B43_DMAIRQ_NONFATALMASK) { - b43err(dev->wl, "DMA error: " - "0x%08X, 0x%08X, 0x%08X, " - "0x%08X, 0x%08X, 0x%08X\n", - dma_reason[0], dma_reason[1], - dma_reason[2], dma_reason[3], - dma_reason[4], dma_reason[5]); - } + /* Fall back to PIO transfers if we get fatal DMA errors! */ + dev->use_pio = true; + b43_controller_restart(dev, "DMA error"); + return; } if (unlikely(reason & B43_IRQ_UCODE_DEBUG)) @@ -1937,6 +1925,11 @@ static void b43_do_interrupt_thread(struct b43_wldev *dev) handle_irq_noise(dev); /* Check the DMA reason registers for received data. */ + if (dma_reason[0] & B43_DMAIRQ_RDESC_UFLOW) { + if (B43_DEBUG) + b43warn(dev->wl, "RX descriptor underrun\n"); + b43_dma_handle_rx_overflow(dev->dma.rx_ring); + } if (dma_reason[0] & B43_DMAIRQ_RX_DONE) { if (b43_using_pio_transfers(dev)) b43_pio_rx(dev->pio.rx_queue); @@ -1994,7 +1987,7 @@ static irqreturn_t b43_do_interrupt(struct b43_wldev *dev) return IRQ_NONE; dev->dma_reason[0] = b43_read32(dev, B43_MMIO_DMA0_REASON) - & 0x0001DC00; + & 0x0001FC00; dev->dma_reason[1] = b43_read32(dev, B43_MMIO_DMA1_REASON) & 0x0000DC00; dev->dma_reason[2] = b43_read32(dev, B43_MMIO_DMA2_REASON) @@ -3126,7 +3119,7 @@ static int b43_chip_init(struct b43_wldev *dev) b43_write32(dev, 0x018C, 0x02000000); } b43_write32(dev, B43_MMIO_GEN_IRQ_REASON, 0x00004000); - b43_write32(dev, B43_MMIO_DMA0_IRQ_MASK, 0x0001DC00); + b43_write32(dev, B43_MMIO_DMA0_IRQ_MASK, 0x0001FC00); b43_write32(dev, B43_MMIO_DMA1_IRQ_MASK, 0x0000DC00); b43_write32(dev, B43_MMIO_DMA2_IRQ_MASK, 0x0000DC00); b43_write32(dev, B43_MMIO_DMA3_IRQ_MASK, 0x0001DC00); |