4.19-stable review patch. If anyone has any objections, please let me know.
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From: Bryan Whitehead Bryan.Whitehead@microchip.com
[ Upstream commit 90490ef7269906423a1c1b917fc24be8b1602658 ]
It has been observed that tx queue stalls while downloading from certain web sites (example www.speedtest.net)
The cause has been tracked down to a corner case where dma descriptors where not setup properly. And there for a tx completion interrupt was not signaled.
This fix corrects the problem by properly marking the end of a multi descriptor transmission.
Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Bryan Whitehead Bryan.Whitehead@microchip.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/microchip/lan743x_main.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)
--- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -1403,7 +1403,8 @@ static int lan743x_tx_frame_start(struct }
static void lan743x_tx_frame_add_lso(struct lan743x_tx *tx, - unsigned int frame_length) + unsigned int frame_length, + int nr_frags) { /* called only from within lan743x_tx_xmit_frame. * assuming tx->ring_lock has already been acquired. @@ -1413,6 +1414,10 @@ static void lan743x_tx_frame_add_lso(str
/* wrap up previous descriptor */ tx->frame_data0 |= TX_DESC_DATA0_EXT_; + if (nr_frags <= 0) { + tx->frame_data0 |= TX_DESC_DATA0_LS_; + tx->frame_data0 |= TX_DESC_DATA0_IOC_; + } tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail]; tx_descriptor->data0 = tx->frame_data0;
@@ -1517,8 +1522,11 @@ static void lan743x_tx_frame_end(struct u32 tx_tail_flags = 0;
/* wrap up previous descriptor */ - tx->frame_data0 |= TX_DESC_DATA0_LS_; - tx->frame_data0 |= TX_DESC_DATA0_IOC_; + if ((tx->frame_data0 & TX_DESC_DATA0_DTYPE_MASK_) == + TX_DESC_DATA0_DTYPE_DATA_) { + tx->frame_data0 |= TX_DESC_DATA0_LS_; + tx->frame_data0 |= TX_DESC_DATA0_IOC_; + }
tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail]; buffer_info = &tx->buffer_info[tx->frame_tail]; @@ -1603,7 +1611,7 @@ static netdev_tx_t lan743x_tx_xmit_frame }
if (gso) - lan743x_tx_frame_add_lso(tx, frame_length); + lan743x_tx_frame_add_lso(tx, frame_length, nr_frags);
if (nr_frags <= 0) goto finish;