1 From fa204fc76c3936c55315ba9423fa7c920af2f9a9 Mon Sep 17 00:00:00 2001
2 From: Ioana Radulescu <ruxandra.radulescu@nxp.com>
3 Date: Wed, 4 Sep 2019 20:32:56 +0300
4 Subject: [PATCH] dpaa2-eth: Add congestion group taildrop
6 The increase in number of ingress frame queues means we now risk
7 depleting the buffer pool before the FQ taildrop kicks in.
9 Congestion group taildrop allows us to control the number of frames
10 that can accumulate on a group of Rx frame queues belonging to the
13 This setting coexists with the frame queue based taildrop: whichever
14 limit gets hit first triggers the frame drop.
16 Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
18 drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 16 ++++++++++++++++
19 drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h | 9 +++++++++
20 2 files changed, 25 insertions(+)
22 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
23 +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
24 @@ -1257,6 +1257,22 @@ static void dpaa2_eth_set_rx_taildrop(st
28 + /* Congestion group taildrop: threshold is in frames, per group
29 + * of FQs belonging to the same traffic class
31 + td.threshold = DPAA2_ETH_CG_TAILDROP_THRESH(priv);
32 + td.units = DPNI_CONGESTION_UNIT_FRAMES;
33 + for (i = 0; i < dpaa2_eth_tc_count(priv); i++) {
34 + err = dpni_set_taildrop(priv->mc_io, 0, priv->mc_token,
35 + DPNI_CP_GROUP, DPNI_QUEUE_RX,
38 + netdev_err(priv->net_dev,
39 + "dpni_set_taildrop(CG) failed\n");
44 priv->rx_td_enabled = td.enable;
47 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
48 +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
50 #define DPAA2_ETH_REFILL_THRESH \
51 (DPAA2_ETH_NUM_BUFS - DPAA2_ETH_BUFS_PER_CMD)
53 +/* Congestion group taildrop threshold: number of frames allowed to accumulate
54 + * at any moment in a group of Rx queues belonging to the same traffic class.
55 + * Choose value such that we don't risk depleting the buffer pool before the
58 +#define DPAA2_ETH_CG_TAILDROP_THRESH(priv) \
59 + (DPAA2_ETH_MAX_FRAMES_PER_QUEUE * dpaa2_eth_queue_count(priv) / \
60 + dpaa2_eth_tc_count(priv))
62 /* Maximum number of buffers that can be acquired/released through a single