From 0e0d39e5f3a3e59c8513b59d4feeeadcb93b707d Mon Sep 17 00:00:00 2001 From: Johannes Stezenbach Date: Mon, 18 Apr 2011 15:29:12 +0200 Subject: rt2800usb: read TX_STA_FIFO asynchronously Trying to fix the "TX status report missed" warnings by reading the TX_STA_FIFO entries as quickly as possible. The TX_STA_FIFO is too small in hardware, thus reading it only from the workqueue is too slow and entries get lost. Start an asynchronous read of the TX_STA_FIFO directly from the TX URB completion callback (atomic context, thus it cannot use the blocking rt2800_register_read()). If the async read returns a valid FIFO entry, it is pushed into a larger FIFO inside struct rt2x00_dev, until rt2800_txdone() picks it up. A .tx_dma_done callback is added to struct rt2x00lib_ops to trigger the async read from the URB completion callback. Signed-off-by: Johannes Stezenbach Signed-off-by: Ivo van Doorn Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2800usb.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'drivers/net/wireless/rt2x00/rt2800usb.c') diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c index f3ce5e854be6..862430e600ad 100644 --- a/drivers/net/wireless/rt2x00/rt2800usb.c +++ b/drivers/net/wireless/rt2x00/rt2800usb.c @@ -98,6 +98,35 @@ static void rt2800usb_stop_queue(struct data_queue *queue) } } +static void rt2800usb_tx_sta_fifo_read_completed(struct rt2x00_dev *rt2x00dev, + int urb_status, u32 tx_status) +{ + if (urb_status) { + WARNING(rt2x00dev, "rt2x00usb_register_read_async failed: %d\n", urb_status); + return; + } + + /* try to read all TX_STA_FIFO entries before scheduling txdone_work */ + if (rt2x00_get_field32(tx_status, TX_STA_FIFO_VALID)) { + if (!kfifo_put(&rt2x00dev->txstatus_fifo, &tx_status)) { + WARNING(rt2x00dev, "TX status FIFO overrun, " + "drop tx status report.\n"); + queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work); + } else + rt2x00usb_register_read_async(rt2x00dev, TX_STA_FIFO, + rt2800usb_tx_sta_fifo_read_completed); + } else if (!kfifo_is_empty(&rt2x00dev->txstatus_fifo)) + queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work); +} + +static void rt2800usb_tx_dma_done(struct queue_entry *entry) +{ + struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev; + + rt2x00usb_register_read_async(rt2x00dev, TX_STA_FIFO, + rt2800usb_tx_sta_fifo_read_completed); +} + /* * Firmware functions */ @@ -565,6 +594,7 @@ static int rt2800usb_probe_hw(struct rt2x00_dev *rt2x00dev) __set_bit(CAPABILITY_HW_CRYPTO, &rt2x00dev->cap_flags); __set_bit(CAPABILITY_LINK_TUNING, &rt2x00dev->cap_flags); __set_bit(REQUIRE_HT_TX_DESC, &rt2x00dev->cap_flags); + __set_bit(REQUIRE_TXSTATUS_FIFO, &rt2x00dev->cap_flags); /* * Set the rssi offset. @@ -635,6 +665,7 @@ static const struct rt2x00lib_ops rt2800usb_rt2x00_ops = { .kick_queue = rt2x00usb_kick_queue, .stop_queue = rt2800usb_stop_queue, .flush_queue = rt2x00usb_flush_queue, + .tx_dma_done = rt2800usb_tx_dma_done, .write_tx_desc = rt2800usb_write_tx_desc, .write_tx_data = rt2800usb_write_tx_data, .write_beacon = rt2800_write_beacon, -- cgit v1.2.3-55-g7522