137 lines
4.1 KiB
Diff
137 lines
4.1 KiB
Diff
From 5e67d4f8a46d19748b501c2ef86de3f50d3cfd51 Mon Sep 17 00:00:00 2001
|
|
From: Gabor Juhos <juhosg@openwrt.org>
|
|
Date: Sun, 24 Mar 2013 19:26:27 +0100
|
|
Subject: [PATCH] rt2x00: rt2800mmio: add a workaround for spurious
|
|
TX_FIFO_STATUS interrupts
|
|
|
|
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
|
|
---
|
|
drivers/net/wireless/ralink/rt2x00/rt2800mmio.c | 72 +++++++++++++++++++++++++-----
|
|
drivers/net/wireless/ralink/rt2x00/rt2x00.h | 5 +++
|
|
2 files changed, 65 insertions(+), 12 deletions(-)
|
|
|
|
--- a/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c
|
|
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800mmio.c
|
|
@@ -415,9 +415,9 @@ void rt2800mmio_autowake_tasklet(unsigne
|
|
}
|
|
EXPORT_SYMBOL_GPL(rt2800mmio_autowake_tasklet);
|
|
|
|
-static void rt2800mmio_txstatus_interrupt(struct rt2x00_dev *rt2x00dev)
|
|
+static void rt2800mmio_txstatus_interrupt(struct rt2x00_dev *rt2x00dev,
|
|
+ u32 status)
|
|
{
|
|
- u32 status;
|
|
int i;
|
|
|
|
/*
|
|
@@ -438,29 +438,77 @@ static void rt2800mmio_txstatus_interrup
|
|
* Since we have only one producer and one consumer we don't
|
|
* need to lock the kfifo.
|
|
*/
|
|
- for (i = 0; i < rt2x00dev->tx->limit; i++) {
|
|
- rt2x00mmio_register_read(rt2x00dev, TX_STA_FIFO, &status);
|
|
-
|
|
- if (!rt2x00_get_field32(status, TX_STA_FIFO_VALID))
|
|
- break;
|
|
-
|
|
+ i = 0;
|
|
+ do {
|
|
if (!kfifo_put(&rt2x00dev->txstatus_fifo, status)) {
|
|
- rt2x00_warn(rt2x00dev, "TX status FIFO overrun, drop tx status report\n");
|
|
+ rt2x00_warn(rt2x00dev,
|
|
+ "TX status FIFO overrun, drop TX status report\n");
|
|
break;
|
|
}
|
|
- }
|
|
+
|
|
+ if (++i >= rt2x00dev->tx->limit)
|
|
+ break;
|
|
+
|
|
+ rt2x00mmio_register_read(rt2x00dev, TX_STA_FIFO, &status);
|
|
+ } while (rt2x00_get_field32(status, TX_STA_FIFO_VALID));
|
|
|
|
/* Schedule the tasklet for processing the tx status. */
|
|
tasklet_schedule(&rt2x00dev->txstatus_tasklet);
|
|
}
|
|
|
|
+#define RT2800MMIO_TXSTATUS_IRQ_MAX_RETRIES 4
|
|
+
|
|
+static bool rt2800mmio_txstatus_is_spurious(struct rt2x00_dev *rt2x00dev,
|
|
+ u32 txstatus)
|
|
+{
|
|
+ if (likely(rt2x00_get_field32(txstatus, TX_STA_FIFO_VALID))) {
|
|
+ rt2x00dev->txstatus_irq_retries = 0;
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ rt2x00dev->txstatus_irq_retries++;
|
|
+
|
|
+ /* Ensure that we don't go into an infinite IRQ loop. */
|
|
+ if (rt2x00dev->txstatus_irq_retries >=
|
|
+ RT2800MMIO_TXSTATUS_IRQ_MAX_RETRIES) {
|
|
+ rt2x00_warn(rt2x00dev,
|
|
+ "%u spurious TX_FIFO_STATUS interrupt(s)\n",
|
|
+ rt2x00dev->txstatus_irq_retries);
|
|
+ rt2x00dev->txstatus_irq_retries = 0;
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ return true;
|
|
+}
|
|
+
|
|
irqreturn_t rt2800mmio_interrupt(int irq, void *dev_instance)
|
|
{
|
|
struct rt2x00_dev *rt2x00dev = dev_instance;
|
|
u32 reg, mask;
|
|
+ u32 txstatus = 0;
|
|
|
|
- /* Read status and ACK all interrupts */
|
|
+ /* Read status */
|
|
rt2x00mmio_register_read(rt2x00dev, INT_SOURCE_CSR, ®);
|
|
+
|
|
+ if (rt2x00_get_field32(reg, INT_SOURCE_CSR_TX_FIFO_STATUS)) {
|
|
+ /* Due to unknown reason the hardware generates a
|
|
+ * TX_FIFO_STATUS interrupt before the TX_STA_FIFO
|
|
+ * register contain valid data. Read the TX status
|
|
+ * here to see if we have to process the actual
|
|
+ * request.
|
|
+ */
|
|
+ rt2x00mmio_register_read(rt2x00dev, TX_STA_FIFO, &txstatus);
|
|
+ if (rt2800mmio_txstatus_is_spurious(rt2x00dev, txstatus)) {
|
|
+ /* Remove the TX_FIFO_STATUS bit so it won't be
|
|
+ * processed in this turn. The hardware will
|
|
+ * generate another IRQ for us.
|
|
+ */
|
|
+ rt2x00_set_field32(®,
|
|
+ INT_SOURCE_CSR_TX_FIFO_STATUS, 0);
|
|
+ }
|
|
+ }
|
|
+
|
|
+ /* ACK interrupts */
|
|
rt2x00mmio_register_write(rt2x00dev, INT_SOURCE_CSR, reg);
|
|
|
|
if (!reg)
|
|
@@ -477,7 +525,7 @@ irqreturn_t rt2800mmio_interrupt(int irq
|
|
mask = ~reg;
|
|
|
|
if (rt2x00_get_field32(reg, INT_SOURCE_CSR_TX_FIFO_STATUS)) {
|
|
- rt2800mmio_txstatus_interrupt(rt2x00dev);
|
|
+ rt2800mmio_txstatus_interrupt(rt2x00dev, txstatus);
|
|
/*
|
|
* Never disable the TX_FIFO_STATUS interrupt.
|
|
*/
|
|
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00.h
|
|
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00.h
|
|
@@ -989,6 +989,11 @@ struct rt2x00_dev {
|
|
int rf_channel;
|
|
|
|
/*
|
|
+ * Counter for tx status irq retries (rt2800pci).
|
|
+ */
|
|
+ unsigned int txstatus_irq_retries;
|
|
+
|
|
+ /*
|
|
* Protect the interrupt mask register.
|
|
*/
|
|
spinlock_t irqmask_lock;
|