From: Ivo van Doorn <ivdoorn@gmail.com>
To: "John W. Linville" <linville@tuxdriver.com>
Cc: linux-wireless@vger.kernel.org, users@rt2x00.serialmonkey.com
Subject: [PATCH 08/23] rt2800usb: read TX_STA_FIFO asynchronously
Date: Mon, 18 Apr 2011 15:29:12 +0200 [thread overview]
Message-ID: <201104181529.13131.IvDoorn@gmail.com> (raw)
In-Reply-To: <201104181528.51457.IvDoorn@gmail.com>
From: Johannes Stezenbach <js@sig21.net>
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 <js@sig21.net>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
---
drivers/net/wireless/rt2x00/rt2800lib.c | 34 ++++++--------------
drivers/net/wireless/rt2x00/rt2800usb.c | 31 ++++++++++++++++++
drivers/net/wireless/rt2x00/rt2x00.h | 1 +
drivers/net/wireless/rt2x00/rt2x00usb.c | 53 +++++++++++++++++++++++++++++++
drivers/net/wireless/rt2x00/rt2x00usb.h | 15 +++++++++
5 files changed, 110 insertions(+), 24 deletions(-)
diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index 0e2c006..d79c8fd 100644
--- a/drivers/net/wireless/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/rt2x00/rt2800lib.c
@@ -730,34 +730,20 @@ void rt2800_txdone(struct rt2x00_dev *rt2x00dev)
struct data_queue *queue;
struct queue_entry *entry;
u32 reg;
- u8 pid;
- int i;
+ u8 qid;
- /*
- * TX_STA_FIFO is a stack of X entries, hence read TX_STA_FIFO
- * at most X times and also stop processing once the TX_STA_FIFO_VALID
- * flag is not set anymore.
- *
- * The legacy drivers use X=TX_RING_SIZE but state in a comment
- * that the TX_STA_FIFO stack has a size of 16. We stick to our
- * tx ring size for now.
- */
- for (i = 0; i < rt2x00dev->ops->tx->entry_num; i++) {
- rt2800_register_read(rt2x00dev, TX_STA_FIFO, ®);
- if (!rt2x00_get_field32(reg, TX_STA_FIFO_VALID))
- break;
+ while (kfifo_get(&rt2x00dev->txstatus_fifo, ®)) {
- /*
- * Skip this entry when it contains an invalid
- * queue identication number.
+ /* TX_STA_FIFO_PID_QUEUE is a 2-bit field, thus
+ * qid is guaranteed to be one of the TX QIDs
*/
- pid = rt2x00_get_field32(reg, TX_STA_FIFO_PID_QUEUE);
- if (pid >= QID_RX)
- continue;
-
- queue = rt2x00queue_get_tx_queue(rt2x00dev, pid);
- if (unlikely(!queue))
+ qid = rt2x00_get_field32(reg, TX_STA_FIFO_PID_QUEUE);
+ queue = rt2x00queue_get_tx_queue(rt2x00dev, qid);
+ if (unlikely(!queue)) {
+ WARNING(rt2x00dev, "Got TX status for an unavailable "
+ "queue %u, dropping\n", qid);
continue;
+ }
/*
* Inside each queue, we process each entry in a chronological
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index f3ce5e8..862430e 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,
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 79c385a..e3b9b51 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -571,6 +571,7 @@ struct rt2x00lib_ops {
void (*kick_queue) (struct data_queue *queue);
void (*stop_queue) (struct data_queue *queue);
void (*flush_queue) (struct data_queue *queue);
+ void (*tx_dma_done) (struct queue_entry *entry);
/*
* TX control handlers
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index 0bc8dcc..5fbab6f 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -165,6 +165,56 @@ int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
}
EXPORT_SYMBOL_GPL(rt2x00usb_regbusy_read);
+
+struct rt2x00_async_read_data {
+ __le32 reg;
+ struct usb_ctrlrequest cr;
+ struct rt2x00_dev *rt2x00dev;
+ void (*callback)(struct rt2x00_dev *,int,u32);
+};
+
+static void rt2x00usb_register_read_async_cb(struct urb *urb)
+{
+ struct rt2x00_async_read_data *rd = urb->context;
+ rd->callback(rd->rt2x00dev, urb->status, le32_to_cpu(rd->reg));
+ kfree(urb->context);
+}
+
+void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset,
+ void (*callback)(struct rt2x00_dev*,int,u32))
+{
+ struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
+ struct urb *urb;
+ struct rt2x00_async_read_data *rd;
+
+ rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
+ if (!rd)
+ return;
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb) {
+ kfree(rd);
+ return;
+ }
+
+ rd->rt2x00dev = rt2x00dev;
+ rd->callback = callback;
+ rd->cr.bRequestType = USB_VENDOR_REQUEST_IN;
+ rd->cr.bRequest = USB_MULTI_READ;
+ rd->cr.wValue = 0;
+ rd->cr.wIndex = cpu_to_le16(offset);
+ rd->cr.wLength = cpu_to_le16(sizeof(u32));
+
+ usb_fill_control_urb(urb, usb_dev, usb_rcvctrlpipe(usb_dev, 0),
+ (unsigned char *)(&rd->cr), &rd->reg, sizeof(rd->reg),
+ rt2x00usb_register_read_async_cb, rd);
+ if (usb_submit_urb(urb, GFP_ATOMIC) < 0)
+ kfree(rd);
+ usb_free_urb(urb);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_register_read_async);
+
/*
* TX data handlers.
*/
@@ -212,6 +262,9 @@ static void rt2x00usb_interrupt_txdone(struct urb *urb)
if (!test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
return;
+ if (rt2x00dev->ops->lib->tx_dma_done)
+ rt2x00dev->ops->lib->tx_dma_done(entry);
+
/*
* Report the frame as DMA done
*/
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.h b/drivers/net/wireless/rt2x00/rt2x00usb.h
index 6aaf51f..e3faca6 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.h
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.h
@@ -345,6 +345,21 @@ int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
const struct rt2x00_field32 field,
u32 *reg);
+/**
+ * rt2x00usb_register_read_async - Asynchronously read 32bit register word
+ * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
+ * @offset: Register offset
+ * @callback: Functon to call when read completes.
+ *
+ * Submit a control URB to read a 32bit register. This safe to
+ * be called from atomic context. The callback will be called
+ * when the URB completes. Otherwise the function is similar
+ * to rt2x00usb_register_read().
+ */
+void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
+ const unsigned int offset,
+ void (*callback)(struct rt2x00_dev*,int,u32));
+
/*
* Radio handlers
*/
--
1.7.2.3
next prev parent reply other threads:[~2011-04-18 13:35 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-18 13:26 [PATCH 01/23] Enable WLAN LED on Ralink SoC (rt305x) devices Ivo van Doorn
2011-04-18 13:26 ` [PATCH 02/23] rt2x00: Fix stuck queue in tx failure case Ivo van Doorn
2011-04-18 13:27 ` [PATCH 03/23] rt2x00: Split rt2x00dev->flags Ivo van Doorn
2011-04-18 13:27 ` [PATCH 04/23] rt2x00: Make rt2x00_queue_entry_for_each more flexible Ivo van Doorn
2011-04-18 13:28 ` [PATCH 05/23] rt2x00: Use correct TBTT_SYNC config in AP mode Ivo van Doorn
2011-04-18 13:28 ` [PATCH 06/23] rt2x00: Update TX_SW_CFG2 init value Ivo van Doorn
2011-04-18 13:28 ` [PATCH 07/23] rt2x00: Use TXOP_HTTXOP for beacons Ivo van Doorn
2011-04-18 13:29 ` Ivo van Doorn [this message]
2011-04-18 13:29 ` [PATCH 09/23] rt2x00: fix queue timeout checks Ivo van Doorn
2011-04-18 13:30 ` [PATCH 10/23] rt2800usb: handle TX status timeouts Ivo van Doorn
2011-04-18 13:30 ` [PATCH 11/23] rt2800usb: add timer to handle TX_STA_FIFO Ivo van Doorn
2011-04-18 13:31 ` [PATCH 12/23] Decrease association time for USB devices Ivo van Doorn
2011-04-18 13:31 ` [PATCH 13/23] rt2x00: Always inline rt2x00pci_enable_interrupt Ivo van Doorn
2011-04-18 13:31 ` [PATCH 14/23] rt2x00: Linksys WUSB600N rev2 is a RT3572 device Ivo van Doorn
2011-04-18 13:32 ` [PATCH 15/23] rt2x00: Allow dynamic addition of PCI/USB IDs Ivo van Doorn
2011-04-18 13:32 ` [PATCH 16/23] rt2x00: Add USB IDs Ivo van Doorn
2011-04-18 13:33 ` [PATCH 17/23] rt2x00: RT33xx device support is no longer experimental Ivo van Doorn
2011-04-18 13:33 ` [PATCH 18/23] rt2x00: Enable support for RT53xx PCI devices by default Ivo van Doorn
2011-04-18 13:33 ` [PATCH 19/23] rt2x00: Merge rt2x00ht.c contents in other files Ivo van Doorn
2011-04-18 13:34 ` [PATCH 20/23] rt2x00: Optimize register access in rt2800pci Ivo van Doorn
2011-04-18 13:34 ` [PATCH 21/23] rt2x00: Optimize register access in rt2800usb Ivo van Doorn
2011-04-18 13:34 ` [PATCH 22/23] rt2x00: Implement get_ringparam callback function Ivo van Doorn
2011-04-18 13:35 ` [PATCH 23/23] rt2x00: Implement get_antenna and set_antenna callback functions Ivo van Doorn
2011-04-18 13:56 ` [PATCH 21/23] rt2x00: Optimize register access in rt2800usb Rafał Miłecki
2011-04-18 14:06 ` Ivo Van Doorn
2011-04-18 14:14 ` Rafał Miłecki
2011-04-18 14:48 ` Helmut Schaa
2011-04-18 15:02 ` Rafał Miłecki
2011-04-28 2:55 ` [PATCH 04/23] rt2x00: Make rt2x00_queue_entry_for_each more flexible Yasushi SHOJI
2011-04-28 2:55 ` Yasushi SHOJI
2011-04-28 18:55 ` Ivo Van Doorn
2011-04-29 6:06 ` Gertjan van Wingerde
2011-04-30 14:01 ` Ivo van Doorn
2011-05-02 13:33 ` Yasushi SHOJI
2011-05-02 19:24 ` Ivo van Doorn
2011-05-09 8:08 ` Yasushi SHOJI
2011-05-09 8:50 ` Ivo Van Doorn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201104181529.13131.IvDoorn@gmail.com \
--to=ivdoorn@gmail.com \
--cc=linux-wireless@vger.kernel.org \
--cc=linville@tuxdriver.com \
--cc=users@rt2x00.serialmonkey.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.