diff options
author | Simon Guinot <simon.guinot@sequanux.org> | 2017-11-13 16:27:02 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-11-14 21:52:25 +0900 |
commit | 0d63785c6b94b5d2f095f90755825f90eea791f5 (patch) | |
tree | 017d1bcdb1e2a4153c08e4ebb3d8ee49b27f9921 /drivers | |
parent | 096d1dd0f03211fb42d6c2457f248827604b7f0e (diff) | |
download | op-kernel-dev-0d63785c6b94b5d2f095f90755825f90eea791f5.zip op-kernel-dev-0d63785c6b94b5d2f095f90755825f90eea791f5.tar.gz |
net: mvneta: fix handling of the Tx descriptor counter
The mvneta controller provides a 8-bit register to update the pending
Tx descriptor counter. Then, a maximum of 255 Tx descriptors can be
added at once. In the current code the mvneta_txq_pend_desc_add function
assumes the caller takes care of this limit. But it is not the case. In
some situations (xmit_more flag), more than 255 descriptors are added.
When this happens, the Tx descriptor counter register is updated with a
wrong value, which breaks the whole Tx queue management.
This patch fixes the issue by allowing the mvneta_txq_pend_desc_add
function to process more than 255 Tx descriptors.
Fixes: 2a90f7e1d5d0 ("net: mvneta: add xmit_more support")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/ethernet/marvell/mvneta.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 64a0497..bc93b69 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -816,11 +816,14 @@ static void mvneta_txq_pend_desc_add(struct mvneta_port *pp, { u32 val; - /* Only 255 descriptors can be added at once ; Assume caller - * process TX desriptors in quanta less than 256 - */ - val = pend_desc + txq->pending; - mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val); + pend_desc += txq->pending; + + /* Only 255 Tx descriptors can be added at once */ + do { + val = min(pend_desc, 255); + mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val); + pend_desc -= val; + } while (pend_desc > 0); txq->pending = 0; } |