[RFC PATCH 0/6] net: ethernet: ti: cpsw: add MQPRIO and CBS Qdisc offload

[RFC PATCH 0/6] net: ethernet: ti: cpsw: add MQPRIO and CBS Qdisc offload

[Ivan Khoronzhuk]

This series adds MQPRIO and CBS Qdisc offload for TI cpsw driver.
It potentially can be used in audio video bridging (AVB) and time
sensitive networking (TSN).

Patchset was tested on AM572x EVM and BBB boards. Last patch from this
series adds detailed description of configuration with examples. For
consistency reasons, in role of talker and listener, tools from
patchset "TSN: Add qdisc based config interface for CBS" were used and
can be seen here: https://www.spinics.net/lists/netdev/msg460869.html

Based on net-next/master

Ivan Khoronzhuk (6):
  net: ethernet: ti: cpsw: use cpdma channels in backward order for txq
  net: ethernet: ti: cpdma: fit rated channels in backward order
  net: ethernet: ti: cpsw: add MQPRIO Qdisc offload
  net: ethernet: ti: cpsw: add CBS Qdisc offload
  net: ethernet: ti: cpsw: restore shaper configuration while down/up
  Documentation: networking: cpsw: add MQPRIO & CBS offload examples

 Documentation/networking/cpsw.txt       | 540 ++++++++++++++++++++++++
 drivers/net/ethernet/ti/cpsw.c          | 364 +++++++++++++++-
 drivers/net/ethernet/ti/davinci_cpdma.c |  31 +-
 3 files changed, 913 insertions(+), 22 deletions(-)
 create mode 100644 Documentation/networking/cpsw.txt

-- 
2.17.0

[RFC PATCH 1/6] net: ethernet: ti: cpsw: use cpdma channels in backward order for txq

[Ivan Khoronzhuk]

The cpdma channel highest priority is from hi to lo number.
The driver has limited number of descriptors that are shared between
number of cpdma channels. Number of queues can be tuned with ethtool,
that allows to not spend descriptors on not needed cpdma channels.
In AVB usually only 2 tx queues can be enough with rate limitation.
The rate limitation can be used only for hi priority queues. Thus, to
use only 2 queues the 8 has to be created. It's wasteful.

So, in order to allow using only needed number of rate limited
tx queues, save resources, and be able to set rate limitation for
them, let assign tx cpdma channels in backward order to queues.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index a7285dddfd29..9bd615da04d3 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -967,8 +967,8 @@ static int cpsw_tx_mq_poll(struct napi_struct *napi_tx, int budget)
 
 	/* process every unprocessed channel */
 	ch_map = cpdma_ctrl_txchs_state(cpsw->dma);
-	for (ch = 0, num_tx = 0; ch_map; ch_map >>= 1, ch++) {
-		if (!(ch_map & 0x01))
+	for (ch = 0, num_tx = 0; ch_map & 0xff; ch_map <<= 1, ch++) {
+		if (!(ch_map & 0x80))
 			continue;
 
 		txv = &cpsw->txv[ch];
@@ -2431,7 +2431,7 @@ static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
 	void (*handler)(void *, int, int);
 	struct netdev_queue *queue;
 	struct cpsw_vector *vec;
-	int ret, *ch;
+	int ret, *ch, vch;
 
 	if (rx) {
 		ch = &cpsw->rx_ch_num;
@@ -2444,7 +2444,8 @@ static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
 	}
 
 	while (*ch < ch_num) {
-		vec[*ch].ch = cpdma_chan_create(cpsw->dma, *ch, handler, rx);
+		vch = rx ? *ch : 7 - *ch;
+		vec[*ch].ch = cpdma_chan_create(cpsw->dma, vch, handler, rx);
 		queue = netdev_get_tx_queue(priv->ndev, *ch);
 		queue->tx_maxrate = 0;
 
@@ -2980,7 +2981,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	u32 slave_offset, sliver_offset, slave_size;
 	const struct soc_device_attribute *soc;
 	struct cpsw_common		*cpsw;
-	int ret = 0, i;
+	int ret = 0, i, ch;
 	int irq;
 
 	cpsw = devm_kzalloc(&pdev->dev, sizeof(struct cpsw_common), GFP_KERNEL);
@@ -3155,7 +3156,8 @@ static int cpsw_probe(struct platform_device *pdev)
 	if (soc)
 		cpsw->quirk_irq = 1;
 
-	cpsw->txv[0].ch = cpdma_chan_create(cpsw->dma, 0, cpsw_tx_handler, 0);
+	ch = cpsw->quirk_irq ? 0 : 7;
+	cpsw->txv[0].ch = cpdma_chan_create(cpsw->dma, ch, cpsw_tx_handler, 0);
 	if (IS_ERR(cpsw->txv[0].ch)) {
 		dev_err(priv->dev, "error initializing tx dma channel\n");
 		ret = PTR_ERR(cpsw->txv[0].ch);
-- 
2.17.0

[RFC PATCH 2/6] net: ethernet: ti: cpdma: fit rated channels in backward order

[Ivan Khoronzhuk]

According to TRM tx rated channels should be in 7..0 order,
so correct it.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/davinci_cpdma.c | 31 ++++++++++++-------------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c
index 31ae04117f0a..37fbdc668cc7 100644
--- a/drivers/net/ethernet/ti/davinci_cpdma.c
+++ b/drivers/net/ethernet/ti/davinci_cpdma.c
@@ -406,37 +406,36 @@ static int cpdma_chan_fit_rate(struct cpdma_chan *ch, u32 rate,
 	struct cpdma_chan *chan;
 	u32 old_rate = ch->rate;
 	u32 new_rmask = 0;
-	int rlim = 1;
+	int rlim = 0;
 	int i;
 
-	*prio_mode = 0;
 	for (i = tx_chan_num(0); i < tx_chan_num(CPDMA_MAX_CHANNELS); i++) {
 		chan = ctlr->channels[i];
-		if (!chan) {
-			rlim = 0;
+		if (!chan)
 			continue;
-		}
 
 		if (chan == ch)
 			chan->rate = rate;
 
 		if (chan->rate) {
-			if (rlim) {
-				new_rmask |= chan->mask;
-			} else {
-				ch->rate = old_rate;
-				dev_err(ctlr->dev, "Prev channel of %dch is not rate limited\n",
-					chan->chan_num);
-				return -EINVAL;
-			}
-		} else {
-			*prio_mode = 1;
-			rlim = 0;
+			rlim = 1;
+			new_rmask |= chan->mask;
+			continue;
 		}
+
+		if (rlim)
+			goto err;
 	}
 
 	*rmask = new_rmask;
+	*prio_mode = rlim;
 	return 0;
+
+err:
+	ch->rate = old_rate;
+	dev_err(ctlr->dev, "Upper cpdma ch%d is not rate limited\n",
+		chan->chan_num);
+	return -EINVAL;
 }
 
 static u32 cpdma_chan_set_factors(struct cpdma_ctlr *ctlr,
-- 
2.17.0

[RFC PATCH 3/6] net: ethernet: ti: cpsw: add MQPRIO Qdisc offload

[Ivan Khoronzhuk]

That's possible to offload vlan to tc priority mapping with
assumption sk_prio == L2 prio.

Example:
$ ethtool -L eth0 rx 1 tx 4

$ qdisc replace dev eth0 handle 100: parent root mqprio num_tc 3 \
map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 1

$ tc -g class show dev eth0
+---(100:ffe2) mqprio
|    +---(100:3) mqprio
|    +---(100:4) mqprio
|    
+---(100:ffe1) mqprio
|    +---(100:2) mqprio
|    
+---(100:ffe0) mqprio
     +---(100:1) mqprio

Here, 100:1 is txq0, 100:2 is txq1, 100:3 is txq2, 100:4 is txq3
txq0 belongs to tc0, txq1 to tc1, txq2 and txq3 to tc2
The offload part only maps L2 prio to classes of traffic, but not
to transmit queues, so to direct traffic to traffic class vlan has
to be created with appropriate egress map.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 82 ++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 9bd615da04d3..4b232cda5436 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -39,6 +39,7 @@
 #include <linux/sys_soc.h>
 
 #include <linux/pinctrl/consumer.h>
+#include <net/pkt_cls.h>
 
 #include "cpsw.h"
 #include "cpsw_ale.h"
@@ -153,6 +154,8 @@ do {								\
 #define IRQ_NUM			2
 #define CPSW_MAX_QUEUES		8
 #define CPSW_CPDMA_DESCS_POOL_SIZE_DEFAULT 256
+#define CPSW_TC_NUM			4
+#define CPSW_FIFO_SHAPERS_NUM		(CPSW_TC_NUM - 1)
 
 #define CPSW_RX_VLAN_ENCAP_HDR_PRIO_SHIFT	29
 #define CPSW_RX_VLAN_ENCAP_HDR_PRIO_MSK		GENMASK(2, 0)
@@ -453,6 +456,7 @@ struct cpsw_priv {
 	u8				mac_addr[ETH_ALEN];
 	bool				rx_pause;
 	bool				tx_pause;
+	bool				mqprio_hw;
 	u32 emac_port;
 	struct cpsw_common *cpsw;
 };
@@ -1577,6 +1581,14 @@ static void cpsw_slave_stop(struct cpsw_slave *slave, struct cpsw_common *cpsw)
 	soft_reset_slave(slave);
 }
 
+static int cpsw_tc_to_fifo(int tc, int num_tc)
+{
+	if (tc == num_tc - 1)
+		return 0;
+
+	return CPSW_FIFO_SHAPERS_NUM - tc;
+}
+
 static int cpsw_ndo_open(struct net_device *ndev)
 {
 	struct cpsw_priv *priv = netdev_priv(ndev);
@@ -2190,6 +2202,75 @@ static int cpsw_ndo_set_tx_maxrate(struct net_device *ndev, int queue, u32 rate)
 	return ret;
 }
 
+static int cpsw_set_tc(struct net_device *ndev, void *type_data)
+{
+	struct tc_mqprio_qopt_offload *mqprio = type_data;
+	struct cpsw_priv *priv = netdev_priv(ndev);
+	struct cpsw_common *cpsw = priv->cpsw;
+	int fifo, num_tc, count, offset;
+	struct cpsw_slave *slave;
+	u32 tx_prio_map = 0;
+	int i, tc, ret;
+
+	num_tc = mqprio->qopt.num_tc;
+	if (num_tc > CPSW_TC_NUM)
+		return -EINVAL;
+
+	if (mqprio->mode != TC_MQPRIO_MODE_DCB)
+		return -EINVAL;
+
+	ret = pm_runtime_get_sync(cpsw->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(cpsw->dev);
+		return ret;
+	}
+
+	if (num_tc) {
+		for (i = 0; i < 8; i++) {
+			tc = mqprio->qopt.prio_tc_map[i];
+			fifo = cpsw_tc_to_fifo(tc, num_tc);
+			tx_prio_map |= fifo << (4 * i);
+		}
+
+		netdev_set_num_tc(ndev, num_tc);
+		for (i = 0; i < num_tc; i++) {
+			count = mqprio->qopt.count[i];
+			offset = mqprio->qopt.offset[i];
+			netdev_set_tc_queue(ndev, i, count, offset);
+		}
+	}
+
+	if (!mqprio->qopt.hw) {
+		/* restore default configuration */
+		netdev_reset_tc(ndev);
+		tx_prio_map = TX_PRIORITY_MAPPING;
+	}
+
+	priv->mqprio_hw = mqprio->qopt.hw;
+
+	offset = cpsw->version == CPSW_VERSION_1 ?
+		 CPSW1_TX_PRI_MAP : CPSW2_TX_PRI_MAP;
+
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	slave_write(slave, tx_prio_map, offset);
+
+	pm_runtime_put_sync(cpsw->dev);
+
+	return 0;
+}
+
+static int cpsw_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
+			     void *type_data)
+{
+	switch (type) {
+	case TC_SETUP_QDISC_MQPRIO:
+		return cpsw_set_tc(ndev, type_data);
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static const struct net_device_ops cpsw_netdev_ops = {
 	.ndo_open		= cpsw_ndo_open,
 	.ndo_stop		= cpsw_ndo_stop,
@@ -2205,6 +2286,7 @@ static const struct net_device_ops cpsw_netdev_ops = {
 #endif
 	.ndo_vlan_rx_add_vid	= cpsw_ndo_vlan_rx_add_vid,
 	.ndo_vlan_rx_kill_vid	= cpsw_ndo_vlan_rx_kill_vid,
+	.ndo_setup_tc           = cpsw_ndo_setup_tc,
 };
 
 static int cpsw_get_regs_len(struct net_device *ndev)
-- 
2.17.0

[RFC PATCH 4/6] net: ethernet: ti: cpsw: add CBS Qdisc offload

[Ivan Khoronzhuk]

The cpsw has up to 4 FIFOs per port and upper 3 FIFOs can feed rate
limited queue with shaping. In order to set and enable shaping for
those 3 FIFOs queues the network device with CBS qdisc attached is
needed. The CBS configuration is added for dual-emac/single port mode
only, but potentially can be used in switch mode also, based on
switchdev for instance.

Despite the FIFO shapers can work w/o cpdma level shapers the base
usage must be in combine with cpdma level shapers as described in TRM,
that are set as maximum rates for interface queues with sysfs.

One of the possible configuration with txq shapers and CBS shapers:

                      Configured with echo RATE >
                  /sys/class/net/eth0/queues/tx-0/tx_maxrate
             /---------------------------------------------------
            /
           /            cpdma level shapers
        +----+ +----+ +----+ +----+ +----+ +----+ +----+ +----+
        | c7 | | c6 | | c5 | | c4 | | c3 | | c2 | | c1 | | c0 |
        \    / \    / \    / \    / \    / \    / \    / \    /
         \  /   \  /   \  /   \  /   \  /   \  /   \  /   \  /
          \/     \/     \/     \/     \/     \/     \/     \/
+---------|------|------|------|-------------------------------------+
|    +----+      |      |  +---+                                     |
|    |      +----+      |  |                                         |
|    v      v           v  v                                         |
| +----+ +----+ +----+ +----+ p        p+----+ +----+ +----+ +----+  |
| |    | |    | |    | |    | o        o|    | |    | |    | |    |  |
| | f3 | | f2 | | f1 | | f0 | r  CPSW  r| f3 | | f2 | | f1 | | f0 |  |
| |    | |    | |    | |    | t        t|    | |    | |    | |    |  |
| \    / \    / \    / \    / 0        1\    / \    / \    / \    /  |
|  \  X   \  /   \  /   \  /             \  /   \  /   \  /   \  /   |
|   \/ \   \/     \/     \/               \/     \/     \/     \/    |
+-------\------------------------------------------------------------+
         \
          \ FIFO shaper, set with CBS offload added in this patch,
           \ FIFO0 cannot be rate limited
            ------------------------------------------------------

CBS shaper configuration is supposed to be used with root MQPRIO Qdisc
offload allowing to add sk_prio->tc->txq maps that direct traffic to
appropriate tx queue and maps L2 priority to FIFO shaper.

The CBS shaper is intended to be used for AVB where L2 priority
(pcp field) is used to differentiate class of traffic. So additionally
vlan needs to be created with appropriate egress sk_prio->l2 prio map.

If CBS has several tx queues assigned to it, the sum of their
bandwidth has not overlap bandwidth set for CBS. It's recomended the
CBS bandwidth to be a little bit more.

The CBS shaper is configured with CBS qdisc offload interface using tc
tool from iproute2 packet.

For instance:

$ tc qdisc replace dev eth0 handle 100: parent root mqprio num_tc 3 \
map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 1

$ tc -g class show dev eth0
+---(100:ffe2) mqprio
|    +---(100:3) mqprio
|    +---(100:4) mqprio
|    
+---(100:ffe1) mqprio
|    +---(100:2) mqprio
|    
+---(100:ffe0) mqprio
     +---(100:1) mqprio

$ tc qdisc add dev eth0 parent 100:1 cbs locredit -1440 \
hicredit 60 sendslope -960000 idleslope 40000 offload 1

$ tc qdisc add dev eth0 parent 100:2 cbs locredit -1470 \
hicredit 62 sendslope -980000 idleslope 20000 offload 1

The above code set CBS shapers for tc0 and tc1, for that txq0 and
txq1 is used. Pay attention, the real set bandwidth can differ a bit
due to discreteness of configuration parameters.

Here parameters like locredit, hicredit and sendslope are ignored
internally and are supposed to be set with assumption that maximum
frame size for frame - 1500.

It's supposed that interface speed is not changed while reconnection,
not always is true, so inform user in case speed of interface was
changed, as it can impact on dependent shapers configuration.

For more examples see Documentation.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 221 +++++++++++++++++++++++++++++++++
 1 file changed, 221 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 4b232cda5436..c7710b0e1c17 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -46,6 +46,8 @@
 #include "cpts.h"
 #include "davinci_cpdma.h"
 
+#include <net/pkt_sched.h>
+
 #define CPSW_DEBUG	(NETIF_MSG_HW		| NETIF_MSG_WOL		| \
 			 NETIF_MSG_DRV		| NETIF_MSG_LINK	| \
 			 NETIF_MSG_IFUP		| NETIF_MSG_INTR	| \
@@ -154,8 +156,12 @@ do {								\
 #define IRQ_NUM			2
 #define CPSW_MAX_QUEUES		8
 #define CPSW_CPDMA_DESCS_POOL_SIZE_DEFAULT 256
+#define CPSW_FIFO_QUEUE_TYPE_SHIFT	16
+#define CPSW_FIFO_SHAPE_EN_SHIFT	16
+#define CPSW_FIFO_RATE_EN_SHIFT		20
 #define CPSW_TC_NUM			4
 #define CPSW_FIFO_SHAPERS_NUM		(CPSW_TC_NUM - 1)
+#define CPSW_PCT_MASK			0x7f
 
 #define CPSW_RX_VLAN_ENCAP_HDR_PRIO_SHIFT	29
 #define CPSW_RX_VLAN_ENCAP_HDR_PRIO_MSK		GENMASK(2, 0)
@@ -457,6 +463,8 @@ struct cpsw_priv {
 	bool				rx_pause;
 	bool				tx_pause;
 	bool				mqprio_hw;
+	int				fifo_bw[CPSW_TC_NUM];
+	int				shp_cfg_speed;
 	u32 emac_port;
 	struct cpsw_common *cpsw;
 };
@@ -1081,6 +1089,38 @@ static void cpsw_set_slave_mac(struct cpsw_slave *slave,
 	slave_write(slave, mac_lo(priv->mac_addr), SA_LO);
 }
 
+static bool cpsw_shp_is_off(struct cpsw_priv *priv)
+{
+	struct cpsw_common *cpsw = priv->cpsw;
+	struct cpsw_slave *slave;
+	u32 shift, mask, val;
+
+	val = readl_relaxed(&cpsw->regs->ptype);
+
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	shift = CPSW_FIFO_SHAPE_EN_SHIFT + 3 * slave->slave_num;
+	mask = 7 << shift;
+	val = val & mask;
+
+	return !val;
+}
+
+static void cpsw_fifo_shp_on(struct cpsw_priv *priv, int fifo, int on)
+{
+	struct cpsw_common *cpsw = priv->cpsw;
+	struct cpsw_slave *slave;
+	u32 shift, mask, val;
+
+	val = readl_relaxed(&cpsw->regs->ptype);
+
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	shift = CPSW_FIFO_SHAPE_EN_SHIFT + 3 * slave->slave_num;
+	mask = (1 << --fifo) << shift;
+	val = on ? val | mask : val & ~mask;
+
+	writel_relaxed(val, &cpsw->regs->ptype);
+}
+
 static void _cpsw_adjust_link(struct cpsw_slave *slave,
 			      struct cpsw_priv *priv, bool *link)
 {
@@ -1120,6 +1160,12 @@ static void _cpsw_adjust_link(struct cpsw_slave *slave,
 			mac_control |= BIT(4);
 
 		*link = true;
+
+		if (priv->shp_cfg_speed &&
+		    priv->shp_cfg_speed != slave->phy->speed &&
+		    !cpsw_shp_is_off(priv))
+			dev_warn(priv->dev,
+				 "Speed was changed, CBS sahper speeds are changed!");
 	} else {
 		mac_control = 0;
 		/* disable forwarding */
@@ -1589,6 +1635,178 @@ static int cpsw_tc_to_fifo(int tc, int num_tc)
 	return CPSW_FIFO_SHAPERS_NUM - tc;
 }
 
+static int cpsw_set_fifo_bw(struct cpsw_priv *priv, int fifo, int bw)
+{
+	struct cpsw_common *cpsw = priv->cpsw;
+	u32 val = 0, send_pct, shift;
+	struct cpsw_slave *slave;
+	int pct = 0, i;
+
+	if (bw > priv->shp_cfg_speed * 1000)
+		goto err;
+
+	/* shaping has to stay enabled for highest fifos linearly
+	 * and fifo bw no more then interface can allow
+	 */
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	send_pct = slave_read(slave, SEND_PERCENT);
+	for (i = CPSW_FIFO_SHAPERS_NUM; i > 0; i--) {
+		if (!bw) {
+			if (i >= fifo || !priv->fifo_bw[i])
+				continue;
+
+			dev_warn(priv->dev, "Prev FIFO%d is shaped", i);
+			continue;
+		}
+
+		if (!priv->fifo_bw[i] && i > fifo) {
+			dev_err(priv->dev, "Upper FIFO%d is not shaped", i);
+			return -EINVAL;
+		}
+
+		shift = (i - 1) * 8;
+		if (i == fifo) {
+			send_pct &= ~(CPSW_PCT_MASK << shift);
+			val = DIV_ROUND_UP(bw, priv->shp_cfg_speed * 10);
+			if (!val)
+				val = 1;
+
+			send_pct |= val << shift;
+			pct += val;
+			continue;
+		}
+
+		if (priv->fifo_bw[i])
+			pct += (send_pct >> shift) & CPSW_PCT_MASK;
+	}
+
+	if (pct >= 100)
+		goto err;
+
+	slave_write(slave, send_pct, SEND_PERCENT);
+	priv->fifo_bw[fifo] = bw;
+
+	dev_warn(priv->dev, "set FIFO%d bw = %d\n", fifo,
+		 DIV_ROUND_CLOSEST(val * priv->shp_cfg_speed, 100));
+
+	return 0;
+err:
+	dev_err(priv->dev, "Bandwidth doesn't fit in tc configuration");
+	return -EINVAL;
+}
+
+static int cpsw_set_fifo_rlimit(struct cpsw_priv *priv, int fifo, int bw)
+{
+	struct cpsw_common *cpsw = priv->cpsw;
+	struct cpsw_slave *slave;
+	u32 tx_in_ctl_rg, val;
+	int ret;
+
+	ret = cpsw_set_fifo_bw(priv, fifo, bw);
+	if (ret)
+		return ret;
+
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	tx_in_ctl_rg = cpsw->version == CPSW_VERSION_1 ?
+		       CPSW1_TX_IN_CTL : CPSW2_TX_IN_CTL;
+
+	if (!bw)
+		cpsw_fifo_shp_on(priv, fifo, bw);
+
+	val = slave_read(slave, tx_in_ctl_rg);
+	if (cpsw_shp_is_off(priv)) {
+		/* disable FIFOs rate limited queues */
+		val &= ~(0xf << CPSW_FIFO_RATE_EN_SHIFT);
+
+		/* set type of FIFO queues to normal priority mode */
+		val &= ~(3 << CPSW_FIFO_QUEUE_TYPE_SHIFT);
+
+		/* set type of FIFO queues to be rate limited */
+		if (bw)
+			val |= 2 << CPSW_FIFO_QUEUE_TYPE_SHIFT;
+		else
+			priv->shp_cfg_speed = 0;
+	}
+
+	/* toggle a FIFO rate limited queue */
+	if (bw)
+		val |= BIT(fifo + CPSW_FIFO_RATE_EN_SHIFT);
+	else
+		val &= ~BIT(fifo + CPSW_FIFO_RATE_EN_SHIFT);
+	slave_write(slave, val, tx_in_ctl_rg);
+
+	/* FIFO transmit shape enable */
+	cpsw_fifo_shp_on(priv, fifo, bw);
+	return 0;
+}
+
+/* Defaults:
+ * class A - prio 3
+ * class B - prio 2
+ * shaping for class A should be set first
+ */
+static int cpsw_set_cbs(struct net_device *ndev,
+			struct tc_cbs_qopt_offload *qopt)
+{
+	struct cpsw_priv *priv = netdev_priv(ndev);
+	struct cpsw_common *cpsw = priv->cpsw;
+	struct cpsw_slave *slave;
+	int prev_speed = 0;
+	int tc, ret, fifo;
+	u32 bw = 0;
+
+	tc = netdev_txq_to_tc(priv->ndev, qopt->queue);
+
+	/* enable channels in backward order, as highest FIFOs must be rate
+	 * limited first and for compliance with CPDMA rate limited channels
+	 * that also used in bacward order. FIFO0 cannot be rate limited.
+	 */
+	fifo = cpsw_tc_to_fifo(tc, ndev->num_tc);
+	if (!fifo) {
+		dev_err(priv->dev, "Last tc%d can't be rate limited", tc);
+		return -EINVAL;
+	}
+
+	/* do nothing, it's disabled anyway */
+	if (!qopt->enable && !priv->fifo_bw[fifo])
+		return 0;
+
+	/* shapers can be set if link speed is known */
+	slave = &cpsw->slaves[cpsw_slave_index(cpsw, priv)];
+	if (slave->phy && slave->phy->link) {
+		if (priv->shp_cfg_speed &&
+		    priv->shp_cfg_speed != slave->phy->speed)
+			prev_speed = priv->shp_cfg_speed;
+
+		priv->shp_cfg_speed = slave->phy->speed;
+	}
+
+	if (!priv->shp_cfg_speed) {
+		dev_err(priv->dev, "Link speed is not known");
+		return -1;
+	}
+
+	ret = pm_runtime_get_sync(cpsw->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(cpsw->dev);
+		return ret;
+	}
+
+	bw = qopt->enable ? qopt->idleslope : 0;
+	ret = cpsw_set_fifo_rlimit(priv, fifo, bw);
+	if (ret) {
+		priv->shp_cfg_speed = prev_speed;
+		prev_speed = 0;
+	}
+
+	if (bw && prev_speed)
+		dev_warn(priv->dev,
+			 "Speed was changed, CBS sahper speeds are changed!");
+
+	pm_runtime_put_sync(cpsw->dev);
+	return ret;
+}
+
 static int cpsw_ndo_open(struct net_device *ndev)
 {
 	struct cpsw_priv *priv = netdev_priv(ndev);
@@ -2263,6 +2481,9 @@ static int cpsw_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
 			     void *type_data)
 {
 	switch (type) {
+	case TC_SETUP_QDISC_CBS:
+		return cpsw_set_cbs(ndev, type_data);
+
 	case TC_SETUP_QDISC_MQPRIO:
 		return cpsw_set_tc(ndev, type_data);
 
-- 
2.17.0

[RFC PATCH 5/6] net: ethernet: ti: cpsw: restore shaper configuration while down/up

[Ivan Khoronzhuk]

Need to restore shapers configuration after interface was down/up.
This is needed as appropriate configuration is still replicated in
kernel settings. This only shapers context restore, so vlan
configuration should be restored by user if needed, especially for
devices with one port where vlan frames are sent via ALE.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 47 ++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index c7710b0e1c17..c3e88be36c1b 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1807,6 +1807,51 @@ static int cpsw_set_cbs(struct net_device *ndev,
 	return ret;
 }
 
+static void cpsw_cbs_resume(struct cpsw_slave *slave, struct cpsw_priv *priv)
+{
+	int fifo, bw;
+
+	for (fifo = CPSW_FIFO_SHAPERS_NUM; fifo > 0; fifo--) {
+		bw = priv->fifo_bw[fifo];
+		if (!bw)
+			continue;
+
+		cpsw_set_fifo_rlimit(priv, fifo, bw);
+	}
+}
+
+static void cpsw_mqprio_resume(struct cpsw_slave *slave, struct cpsw_priv *priv)
+{
+	struct cpsw_common *cpsw = priv->cpsw;
+	u32 tx_prio_map = 0;
+	int i, tc, fifo;
+	u32 tx_prio_rg;
+
+	if (!priv->mqprio_hw)
+		return;
+
+	for (i = 0; i < 8; i++) {
+		tc = netdev_get_prio_tc_map(priv->ndev, i);
+		fifo = CPSW_FIFO_SHAPERS_NUM - tc;
+		tx_prio_map |= fifo << (4 * i);
+	}
+
+	tx_prio_rg = cpsw->version == CPSW_VERSION_1 ?
+		     CPSW1_TX_PRI_MAP : CPSW2_TX_PRI_MAP;
+
+	slave_write(slave, tx_prio_map, tx_prio_rg);
+}
+
+/* restore resources after port reset */
+static void cpsw_restore(struct cpsw_priv *priv)
+{
+	/* restore MQPRIO offload */
+	for_each_slave(priv, cpsw_mqprio_resume, priv);
+
+	/* restore CBS offload */
+	for_each_slave(priv, cpsw_cbs_resume, priv);
+}
+
 static int cpsw_ndo_open(struct net_device *ndev)
 {
 	struct cpsw_priv *priv = netdev_priv(ndev);
@@ -1886,6 +1931,8 @@ static int cpsw_ndo_open(struct net_device *ndev)
 
 	}
 
+	cpsw_restore(priv);
+
 	/* Enable Interrupt pacing if configured */
 	if (cpsw->coal_intvl != 0) {
 		struct ethtool_coalesce coal;
-- 
2.17.0

[RFC PATCH 6/6] Documentation: networking: cpsw: add MQPRIO & CBS offload examples

[Ivan Khoronzhuk]

This document describes MQPRIO and CBS Qdisc offload configuration
for cpsw driver based on examples. It potentially can be used in
audio video bridging (AVB) and time sensitive networking (TSN).

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 Documentation/networking/cpsw.txt | 540 ++++++++++++++++++++++++++++++
 1 file changed, 540 insertions(+)
 create mode 100644 Documentation/networking/cpsw.txt

diff --git a/Documentation/networking/cpsw.txt b/Documentation/networking/cpsw.txt
new file mode 100644
index 000000000000..28c64896d59d
--- /dev/null
+++ b/Documentation/networking/cpsw.txt
@@ -0,0 +1,540 @@
+* Texas Instruments CPSW ethernet driver
+
+Multiqueue & CBS & MQPRIO
+=====================================================================
+=====================================================================
+
+The cpsw has 3 CBS shapers for each external ports. This document
+describes MQPRIO and CBS Qdisc offload configuration for cpsw driver
+based on examples. It potentially can be used in audio video bridging
+(AVB) and time sensitive networking (TSN).
+
+The following examples was tested on AM572x EVM and BBB boards.
+
+Test setup
+==========
+
+Under consideration two examples with AM52xx EVM running cpsw driver
+in dual_emac mode.
+
+Several prerequisites:
+- TX queues must be rated starting from txq0 that has highest priority
+- Traffic classes are used starting from 0, that has highest priority
+- CBS shapers should be used with rated queues
+- The bandwidth for CBS shapers has to be set a little bit more then
+  potential incoming rate, thus, rate of all incoming tx queues has
+  to be a little less
+- Real rates can differ, due to discreetness
+- Map skb-priority to txq is not enough, also skb-priority to l2 prio
+  map has to be created with ip or vconfig tool
+- Any l2/socket prio (0 - 7) for classes can be used, but for
+  simplicity default values are used: 3 and 2
+- only 2 classes tested: A and B, but checked and can work with more,
+  maximum allowed 4, but only for 3 rate can be set.
+
+Test setup for examples
+=======================
+                                    +-------------------------------+
+                                    |--+                            |
+                                    |  |      Workstation0          |
+                                    |E |  MAC 18:03:73:66:87:42     |
++-----------------------------+  +--|t |                            |
+|                    | 1  | E |  |  |h |./tsn_listener -d \         |
+|  Target board:     | 0  | t |--+  |0 | 18:03:73:66:87:42 -i eth0 \|
+|  AM572x EVM        | 0  | h |     |  | -s 1500                    |
+|                    | 0  | 0 |     |--+                            |
+|  Only 2 classes:   |Mb  +---|     +-------------------------------+
+|  class A, class B  |        |
+|                    |    +---|     +-------------------------------+
+|                    | 1  | E |     |--+                            |
+|                    | 0  | t |     |  |      Workstation1          |
+|                    | 0  | h |--+  |E |  MAC 20:cf:30:85:7d:fd     |
+|                    |Mb  | 1 |  +--|t |                            |
++-----------------------------+     |h |./tsn_listener -d \         |
+                                    |0 | 20:cf:30:85:7d:fd -i eth0 \|
+                                    |  | -s 1500                    |
+                                    |--+                            |
+                                    +-------------------------------+
+
+*********************************************************************
+*********************************************************************
+*********************************************************************
+Example 1: One port tx AVB configuration scheme for target board
+----------------------------------------------------------------------
+(prints and scheme for AM52xx evm, applicable for single port boards)
+
+tc - traffic class
+txq - transmit queue
+p - priority
+f - fifo (cpsw fifo)
+S - shaper configured
+
++------------------------------------------------------------------+ u
+| +---------------+  +---------------+  +------+ +------+          | s
+| |               |  |               |  |      | |      |          | e
+| | App 1         |  | App 2         |  | Apps | | Apps |          | r
+| | Class A       |  | Class B       |  | Rest | | Rest |          |
+| | Eth0          |  | Eth0          |  | Eth0 | | Eth1 |          | s
+| | VLAN100       |  | VLAN100       |  |   |  | |   |  |          | p
+| | 40 Mb/s       |  | 20 Mb/s       |  |   |  | |   |  |          | a
+| | SO_PRIORITY=3 |  | SO_PRIORITY=2 |  |   |  | |   |  |          | c
+| |   |           |  |   |           |  |   |  | |   |  |          | e
+| +---|-----------+  +---|-----------+  +---|--+ +---|--+          |
++-----|------------------|------------------|--------|-------------+
+    +-+     +------------+                  |        |
+    |       |             +-----------------+     +--+
+    |       |             |                       |
++---|-------|-------------|-----------------------|----------------+
+| +----+ +----+ +----+ +----+                   +----+             |
+| | p3 | | p2 | | p1 | | p0 |                   | p0 |             | k
+| \    / \    / \    / \    /                   \    /             | e
+|  \  /   \  /   \  /   \  /                     \  /              | r
+|   \/     \/     \/     \/                       \/               | n
+|    |     |             |                        |                | e
+|    |     |       +-----+                        |                | l
+|    |     |       |                              |                |
+| +----+ +----+ +----+                          +----+             | s
+| |tc0 | |tc1 | |tc2 |                          |tc0 |             | p
+| \    / \    / \    /                          \    /             | a
+|  \  /   \  /   \  /                            \  /              | c
+|   \/     \/     \/                              \/               | e
+|   |      |       +-----+                        |                |
+|   |      |       |     |                        |                |
+|   |      |       |     |                        |                |
+|   |      |       |     |                        |                |
+| +----+ +----+ +----+ +----+                   +----+             |
+| |txq0| |txq1| |txq2| |txq3|                   |txq4|             |
+| \    / \    / \    / \    /                   \    /             |
+|  \  /   \  /   \  /   \  /                     \  /              |
+|   \/     \/     \/     \/                       \/               |
+| +-|------|------|------|--+                  +--|--------------+ |
+| | |      |      |      |  | Eth0.100         |  |     Eth1     | |
++---|------|------|------|------------------------|----------------+
+    |      |      |      |                        |
+    p      p      p      p                        |
+    3      2      0-1, 4-7  <- L2 priority        |
+    |      |      |      |                        |
+    |      |      |      |                        |
++---|------|------|------|------------------------|----------------+
+|   |      |      |      |             |----------+                |
+| +----+ +----+ +----+ +----+       +----+                         |
+| |dma7| |dma6| |dma5| |dma4|       |dma4|                         |
+| \    / \    / \    / \    /       \    /                         | c
+|  \S /   \S /   \  /   \  /         \  /                          | p
+|   \/     \/     \/     \/           \/                           | s
+|   |      |      | +-----            |                            | w
+|   |      |      | |                 |                            |
+|   |      |      | |                 |                            | d
+| +----+ +----+ +----+p            p+----+                         | r
+| |    | |    | |    |o            o|    |                         | i
+| | f3 | | f2 | | f0 |r            r| f0 |                         | v
+| |tc0 | |tc1 | |tc2 |t            t|tc0 |                         | e
+| \CBS / \CBS / \CBS /1            2\CBS /                         | r
+|  \S /   \S /   \  /                \  /                          |
+|   \/     \/     \/                  \/                           |
++------------------------------------------------------------------+
+========================================Eth==========================>
+
+1)
+// Add 4 tx queues, for interface Eth0, and 1 tx queue for Eth1
+$ ethtool -L eth0 rx 1 tx 5
+rx unmodified, ignoring
+
+2)
+// Check if num of queues is set correctly:
+$ ethtool -l eth0
+Channel parameters for eth0:
+Pre-set maximums:
+RX:             8
+TX:             8
+Other:          0
+Combined:       0
+Current hardware settings:
+RX:             1
+TX:             5
+Other:          0
+Combined:       0
+
+3)
+// TX queues must be rated starting from 0, so set bws for tx0 and tx1
+// Set rates 40 and 20 Mb/s appropriately.
+// Pay attention, real speed can differ a bit due to discreetness.
+// Leave last 2 tx queues not rated.
+$ echo 40 > /sys/class/net/eth0/queues/tx-0/tx_maxrate
+$ echo 20 > /sys/class/net/eth0/queues/tx-1/tx_maxrate
+
+4)
+// Check maximum rate of tx (cpdma) queues:
+$ cat /sys/class/net/eth0/queues/tx-*/tx_maxrate
+40
+20
+0
+0
+0
+
+5)
+// Map skb->priority to traffic class:
+// 3pri -> tc0, 2pri -> tc1, (0,1,4-7)pri -> tc2
+// Map traffic class to transmit queue:
+// tc0 -> txq0, tc1 -> txq1, tc2 -> (txq2, txq3)
+$ tc qdisc replace dev eth0 handle 100: parent root mqprio num_tc 3 \
+map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 1
+
+5a)
+// As two interface sharing same set of tx queues, assign all traffic
+// coming to interface Eth1 to separate queue in order to not mix it
+// with traffic from interface Eth0, so use separate txq to send
+// packets to Eth1, so all prio -> tc0 and tc0 -> txq4
+// Here hw 0, so here still default configuration for eth1 in hw
+$ tc qdisc replace dev eth1 handle 100: parent root mqprio num_tc 1 \
+map 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 queues 1@4 hw 0
+
+6)
+// Check classes settings
+$ tc -g class show dev eth0
++---(100:ffe2) mqprio
+|    +---(100:3) mqprio
+|    +---(100:4) mqprio
+|
++---(100:ffe1) mqprio
+|    +---(100:2) mqprio
+|
++---(100:ffe0) mqprio
+     +---(100:1) mqprio
+
+$ tc -g class show dev eth1
++---(100:ffe0) mqprio
+     +---(100:5) mqprio
+
+7)
+// Set rate for class A - 41 Mbit (tc0, txq0) using CBS Qdisc
+// Set it +1 Mb for reserve (important!)
+// here only idle slope is important, others arg are ignored
+// Pay attention, real speed can differ a bit due to discreetness
+$ tc qdisc add dev eth0 parent 100:1 cbs locredit -1438 \
+hicredit 62 sendslope -959000 idleslope 41000 offload 1
+net eth0: set FIFO3 bw = 50
+
+8)
+// Set rate for class B - 21 Mbit (tc1, txq1) using CBS Qdisc:
+// Set it +1 Mb for reserve (important!)
+$ tc qdisc add dev eth0 parent 100:2 cbs locredit -1468 \
+hicredit 65 sendslope -979000 idleslope 21000 offload 1
+net eth0: set FIFO2 bw = 30
+
+9)
+// Create vlan 100 to map sk->priority to vlan qos
+$ ip link add link eth0 name eth0.100 type vlan id 100
+8021q: 802.1Q VLAN Support v1.8
+8021q: adding VLAN 0 to HW filter on device eth0
+8021q: adding VLAN 0 to HW filter on device eth1
+net eth0: Adding vlanid 100 to vlan filter
+
+10)
+// Map skb->priority to L2 prio, 1 to 1
+$ ip link set eth0.100 type vlan \
+egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+11)
+// Check egress map for vlan 100
+$ cat /proc/net/vlan/eth0.100
+[...]
+INGRESS priority mappings: 0:0  1:0  2:0  3:0  4:0  5:0  6:0 7:0
+EGRESS priority mappings: 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+12)
+// Run your appropriate tools with socket option "SO_PRIORITY"
+// to 3 for class A and/or to 2 for class B
+// (I took at https://www.spinics.net/lists/netdev/msg460869.html)
+./tsn_talker -d 18:03:73:66:87:42 -i eth0.100 -p3 -s 1500&
+./tsn_talker -d 18:03:73:66:87:42 -i eth0.100 -p2 -s 1500&
+
+13)
+// run your listener on workstation
+// (I took at https://www.spinics.net/lists/netdev/msg460869.html)
+./tsn_listener -d 18:03:73:66:87:42 -i enp5s0 -s 1500
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39000 kbps
+
+14)
+// Restore default configuration if needed
+$ ip link del eth0.100
+$ tc qdisc del dev eth1 root
+$ tc qdisc del dev eth0 root
+net eth0: Prev FIFO2 is shaped
+net eth0: set FIFO3 bw = 0
+net eth0: set FIFO2 bw = 0
+$ ethtool -L eth0 rx 1 tx 1
+
+*********************************************************************
+*********************************************************************
+*********************************************************************
+Example 2: Two port tx AVB configuration scheme for target board
+----------------------------------------------------------------------
+(prints and scheme for AM52xx evm, for dual emac boards only)
+
++------------------------------------------------------------------+ u
+| +----------+  +----------+  +------+  +----------+  +----------+ | s
+| |          |  |          |  |      |  |          |  |          | | e
+| | App 1    |  | App 2    |  | Apps |  | App 3    |  | App 4    | | r
+| | Class A  |  | Class B  |  | Rest |  | Class B  |  | Class A  | |
+| | Eth0     |  | Eth0     |  |   |  |  | Eth1     |  | Eth1     | | s
+| | VLAN100  |  | VLAN100  |  |   |  |  | VLAN100  |  | VLAN100  | | p
+| | 40 Mb/s  |  | 20 Mb/s  |  |   |  |  | 10 Mb/s  |  | 30 Mb/s  | | a
+| | SO_PRI=3 |  | SO_PRI=2 |  |   |  |  | SO_PRI=3 |  | SO_PRI=2 | | c
+| |   |      |  |   |      |  |   |  |  |   |      |  |   |      | | e
+| +---|------+  +---|------+  +---|--+  +---|------+  +---|------+ |
++-----|-------------|-------------|---------|-------------|--------+
+    +-+     +-------+             |         +----------+  +----+
+    |       |             +-------+------+             |       |
+    |       |             |              |             |       |
++---|-------|-------------|--------------|-------------|-------|---+
+| +----+ +----+ +----+ +----+          +-+--+ +----+ +----+ +----+ |
+| | p3 | | p2 | | p1 | | p0 |          | p0 | | p1 | | p2 | | p3 | | k
+| \    / \    / \    / \    /          \    / \    / \    / \    / | e
+|  \  /   \  /   \  /   \  /            \  /   \  /   \  /   \  /  | r
+|   \/     \/     \/     \/              \/     \/     \/     \/   | n
+|   |      |             |                |             |      |   | e
+|   |      |        +----+                +----+        |      |   | l
+|   |      |        |                          |        |      |   |
+| +----+ +----+ +----+                        +----+ +----+ +----+ | s
+| |tc0 | |tc1 | |tc2 |                        |tc2 | |tc1 | |tc0 | | p
+| \    / \    / \    /                        \    / \    / \    / | a
+|  \  /   \  /   \  /                          \  /   \  /   \  /  | c
+|   \/     \/     \/                            \/     \/     \/   | e
+|   |      |       +-----+                +-----+      |       |   |
+|   |      |       |     |                |     |      |       |   |
+|   |      |       |     |                |     |      |       |   |
+|   |      |       |     |    E      E    |     |      |       |   |
+| +----+ +----+ +----+ +----+ t      t +----+ +----+ +----+ +----+ |
+| |txq0| |txq1| |txq4| |txq5| h      h |txq6| |txq7| |txq3| |txq2| |
+| \    / \    / \    / \    / 0      1 \    / \    / \    / \    / |
+|  \  /   \  /   \  /   \  /  .      .  \  /   \  /   \  /   \  /  |
+|   \/     \/     \/     \/   1      1   \/     \/     \/     \/   |
+| +-|------|------|------|--+ 0      0 +-|------|------|------|--+ |
+| | |      |      |      |  | 0      0 | |      |      |      |  | |
++---|------|------|------|---------------|------|------|------|----+
+    |      |      |      |               |      |      |      |
+    p      p      p      p               p      p      p      p
+    3      2      0-1, 4-7   <-L2 pri->  0-1, 4-7      2      3
+    |      |      |      |               |      |      |      |
+    |      |      |      |               |      |      |      |
++---|------|------|------|---------------|------|------|------|----+
+|   |      |      |      |               |      |      |      |    |
+| +----+ +----+ +----+ +----+          +----+ +----+ +----+ +----+ |
+| |dma7| |dma6| |dma3| |dma2|          |dma1| |dma0| |dma4| |dma5| |
+| \    / \    / \    / \    /          \    / \    / \    / \    / | c
+|  \S /   \S /   \  /   \  /            \  /   \  /   \S /   \S /  | p
+|   \/     \/     \/     \/              \/     \/     \/     \/   | s
+|   |      |      | +-----                |      |      |      |   | w
+|   |      |      | |                     +----+ |      |      |   |
+|   |      |      | |                          | |      |      |   | d
+| +----+ +----+ +----+p                      p+----+ +----+ +----+ | r
+| |    | |    | |    |o                      o|    | |    | |    | | i
+| | f3 | | f2 | | f0 |r        CPSW          r| f3 | | f2 | | f0 | | v
+| |tc0 | |tc1 | |tc2 |t                      t|tc0 | |tc1 | |tc2 | | e
+| \CBS / \CBS / \CBS /1                      2\CBS / \CBS / \CBS / | r
+|  \S /   \S /   \  /                          \S /   \S /   \  /  |
+|   \/     \/     \/                            \/     \/     \/   |
++------------------------------------------------------------------+
+========================================Eth==========================>
+
+1)
+// Add 8 tx queues, for interface Eth0, but they are common, so are accessed
+// by two interfaces Eth0 and Eth1.
+$ ethtool -L eth1 rx 1 tx 8
+rx unmodified, ignoring
+
+2)
+// Check if num of queues is set correctly:
+$ ethtool -l eth0
+Channel parameters for eth0:
+Pre-set maximums:
+RX:             8
+TX:             8
+Other:          0
+Combined:       0
+Current hardware settings:
+RX:             1
+TX:             8
+Other:          0
+Combined:       0
+
+3)
+// TX queues must be rated starting from 0, so set bws for tx0 and tx1 for Eth0
+// and for tx2 and tx3 for Eth1. That is, rates 40 and 20 Mb/s appropriately
+// for Eth0 and 30 and 10 Mb/s for Eth1.
+// Real speed can differ a bit due to discreetness
+// Leave last 4 tx queues as not rated
+$ echo 40 > /sys/class/net/eth0/queues/tx-0/tx_maxrate
+$ echo 20 > /sys/class/net/eth0/queues/tx-1/tx_maxrate
+$ echo 30 > /sys/class/net/eth1/queues/tx-2/tx_maxrate
+$ echo 10 > /sys/class/net/eth1/queues/tx-3/tx_maxrate
+
+4)
+// Check maximum rate of tx (cpdma) queues:
+$ cat /sys/class/net/eth0/queues/tx-*/tx_maxrate
+40
+20
+30
+10
+0
+0
+0
+0
+
+5)
+// Map skb->priority to traffic class for Eth0:
+// 3pri -> tc0, 2pri -> tc1, (0,1,4-7)pri -> tc2
+// Map traffic class to transmit queue:
+// tc0 -> txq0, tc1 -> txq1, tc2 -> (txq4, txq5)
+$ tc qdisc replace dev eth0 handle 100: parent root mqprio num_tc 3 \
+map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@4 hw 1
+
+6)
+// Check classes settings
+$ tc -g class show dev eth0
++---(100:ffe2) mqprio
+|    +---(100:5) mqprio
+|    +---(100:6) mqprio
+|
++---(100:ffe1) mqprio
+|    +---(100:2) mqprio
+|
++---(100:ffe0) mqprio
+     +---(100:1) mqprio
+
+7)
+// Set rate for class A - 41 Mbit (tc0, txq0) using CBS Qdisc for Eth0
+// here only idle slope is important, others ignored
+// Real speed can differ a bit due to discreetness
+$ tc qdisc add dev eth0 parent 100:1 cbs locredit -1470 \
+hicredit 62 sendslope -959000 idleslope 41000 offload 1
+net eth0: set FIFO3 bw = 50
+
+8)
+// Set rate for class B - 21 Mbit (tc1, txq1) using CBS Qdisc for Eth0
+$ tc qdisc add dev eth0 parent 100:2 cbs locredit -1470 \
+hicredit 65 sendslope -979000 idleslope 21000 offload 1
+net eth0: set FIFO2 bw = 30
+
+9)
+// Create vlan 100 to map sk->priority to vlan qos for Eth0
+$ ip link add link eth0 name eth0.100 type vlan id 100
+net eth0: Adding vlanid 100 to vlan filter
+
+10)
+// Map skb->priority to L2 prio for Eth0.100, one to one
+$ ip link set eth0.100 type vlan \
+egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+11)
+// Check egress map for vlan 100
+$ cat /proc/net/vlan/eth0.100
+[...]
+INGRESS priority mappings: 0:0  1:0  2:0  3:0  4:0  5:0  6:0 7:0
+EGRESS priority mappings: 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+12)
+// Map skb->priority to traffic class for Eth1:
+// 3pri -> tc0, 2pri -> tc1, (0,1,4-7)pri -> tc2
+// Map traffic class to transmit queue:
+// tc0 -> txq2, tc1 -> txq3, tc2 -> (txq6, txq7)
+$ tc qdisc replace dev eth1 handle 100: parent root mqprio num_tc 3 \
+map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@2 1@3 2@6 hw 1
+
+13)
+// Check classes settings
+$ tc -g class show dev eth1
++---(100:ffe2) mqprio
+|    +---(100:7) mqprio
+|    +---(100:8) mqprio
+|
++---(100:ffe1) mqprio
+|    +---(100:4) mqprio
+|
++---(100:ffe0) mqprio
+     +---(100:3) mqprio
+
+14)
+// Set rate for class A - 31 Mbit (tc0, txq2) using CBS Qdisc for Eth1
+// here only idle slope is important, others ignored
+// Set it +1 Mb for reserve (important!)
+$ tc qdisc add dev eth1 parent 100:1 cbs locredit -1453 \
+hicredit 47 sendslope -969000 idleslope 31000 offload 1
+net eth1: set FIFO3 bw = 40
+
+15)
+// Set rate for class B - 11 Mbit (tc1, txq3) using CBS Qdisc for Eth1
+// Set it +1 Mb for reserve (important!)
+$ tc qdisc add dev eth1 parent 100:2 cbs locredit -1483 \
+hicredit 34 sendslope -989000 idleslope 11000 offload 1
+net eth1: set FIFO2 bw = 20
+
+16)
+// Create vlan 100 to map sk->priority to vlan qos for Eth1
+$ ip link add link eth1 name eth1.100 type vlan id 100
+net eth1: Adding vlanid 100 to vlan filter
+
+17)
+// Map skb->priority to L2 prio for Eth1.100, one to one
+$ ip link set eth1.100 type vlan \
+egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+18)
+// Check egress map for vlan 100
+$ cat /proc/net/vlan/eth1.100
+[...]
+INGRESS priority mappings: 0:0  1:0  2:0  3:0  4:0  5:0  6:0 7:0
+EGRESS priority mappings: 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+19)
+// Run appropriate tools with socket option "SO_PRIORITY" to 3
+// for class A and to 2 for class B. For both interfaces
+./tsn_talker -d 18:03:73:66:87:42 -i eth0.100 -p2 -s 1500&
+./tsn_talker -d 18:03:73:66:87:42 -i eth0.100 -p3 -s 1500&
+./tsn_talker -d 20:cf:30:85:7d:fd -i eth1.100 -p2 -s 1500&
+./tsn_talker -d 20:cf:30:85:7d:fd -i eth1.100 -p3 -s 1500&
+
+20)
+// run your listeners on workstations
+// (I took at https://www.spinics.net/lists/netdev/msg460869.html)
+./tsn_listener -d 18:03:73:66:87:42 -i enp5s0 -s 1500
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39012 kbps
+Receiving data rate: 39000 kbps
+
+21)
+// Restore default configuration if needed
+$ ip link del eth1.100
+$ ip link del eth0.100
+$ tc qdisc del dev eth1 root
+net eth1: Prev FIFO2 is shaped
+net eth1: set FIFO3 bw = 0
+net eth1: set FIFO2 bw = 0
+$ tc qdisc del dev eth0 root
+net eth0: Prev FIFO2 is shaped
+net eth0: set FIFO3 bw = 0
+net eth0: set FIFO2 bw = 0
+$ ethtool -L eth0 rx 1 tx 1
-- 
2.17.0

Re: [RFC PATCH 0/6] net: ethernet: ti: cpsw: add MQPRIO and CBS Qdisc offload

[Grygorii Strashko]

Hi Ivan,

On 05/18/2018 04:15 PM, Ivan Khoronzhuk wrote:
> This series adds MQPRIO and CBS Qdisc offload for TI cpsw driver.
> It potentially can be used in audio video bridging (AVB) and time
> sensitive networking (TSN).
> 
> Patchset was tested on AM572x EVM and BBB boards. Last patch from this
> series adds detailed description of configuration with examples. For
> consistency reasons, in role of talker and listener, tools from
> patchset "TSN: Add qdisc based config interface for CBS" were used and
> can be seen here: https://www.spinics.net/lists/netdev/msg460869.html
> 
> Based on net-next/master

Thanks a lot, it is great work.

In general I have no comments as of now, but I prefer to wait a bit (few 
weeks) for more comments and possible test reports.

If no comments, pls feel free to repost as final series.


> 
> Ivan Khoronzhuk (6):
>    net: ethernet: ti: cpsw: use cpdma channels in backward order for txq
>    net: ethernet: ti: cpdma: fit rated channels in backward order
>    net: ethernet: ti: cpsw: add MQPRIO Qdisc offload
>    net: ethernet: ti: cpsw: add CBS Qdisc offload
>    net: ethernet: ti: cpsw: restore shaper configuration while down/up
>    Documentation: networking: cpsw: add MQPRIO & CBS offload examples
> 
>   Documentation/networking/cpsw.txt       | 540 ++++++++++++++++++++++++
>   drivers/net/ethernet/ti/cpsw.c          | 364 +++++++++++++++-
>   drivers/net/ethernet/ti/davinci_cpdma.c |  31 +-
>   3 files changed, 913 insertions(+), 22 deletions(-)
>   create mode 100644 Documentation/networking/cpsw.txt
> 

-- 
regards,
-grygorii

Re: [RFC PATCH 0/6] net: ethernet: ti: cpsw: add MQPRIO and CBS Qdisc offload

[Vinicius Costa Gomes]

Hi Ivan,

Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> writes:

> This series adds MQPRIO and CBS Qdisc offload for TI cpsw driver.
> It potentially can be used in audio video bridging (AVB) and time
> sensitive networking (TSN).
>
> Patchset was tested on AM572x EVM and BBB boards. Last patch from this
> series adds detailed description of configuration with examples. For
> consistency reasons, in role of talker and listener, tools from
> patchset "TSN: Add qdisc based config interface for CBS" were used and
> can be seen here: https://www.spinics.net/lists/netdev/msg460869.html
>
> Based on net-next/master
>

I didn't test this, but it looks fine from my side.

I agree with Grygorii, that if no comments, this should be re-sent as a
patch series next.


> Ivan Khoronzhuk (6):
>   net: ethernet: ti: cpsw: use cpdma channels in backward order for txq
>   net: ethernet: ti: cpdma: fit rated channels in backward order
>   net: ethernet: ti: cpsw: add MQPRIO Qdisc offload
>   net: ethernet: ti: cpsw: add CBS Qdisc offload
>   net: ethernet: ti: cpsw: restore shaper configuration while down/up
>   Documentation: networking: cpsw: add MQPRIO & CBS offload examples
>
>  Documentation/networking/cpsw.txt       | 540 ++++++++++++++++++++++++
>  drivers/net/ethernet/ti/cpsw.c          | 364 +++++++++++++++-
>  drivers/net/ethernet/ti/davinci_cpdma.c |  31 +-
>  3 files changed, 913 insertions(+), 22 deletions(-)
>  create mode 100644 Documentation/networking/cpsw.txt
>
> -- 
> 2.17.0


Cheers,
--
Vinicius

Re: [RFC PATCH 0/6] net: ethernet: ti: cpsw: add MQPRIO and CBS Qdisc offload

[Ivan Khoronzhuk]

On Mon, Jun 04, 2018 at 02:23:56PM -0300, Vinicius Costa Gomes wrote:
>Hi Ivan,
>
>Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> writes:
>
>> This series adds MQPRIO and CBS Qdisc offload for TI cpsw driver.
>> It potentially can be used in audio video bridging (AVB) and time
>> sensitive networking (TSN).
>>
>> Patchset was tested on AM572x EVM and BBB boards. Last patch from this
>> series adds detailed description of configuration with examples. For
>> consistency reasons, in role of talker and listener, tools from
>> patchset "TSN: Add qdisc based config interface for CBS" were used and
>> can be seen here: https://www.spinics.net/lists/netdev/msg460869.html
>>
>> Based on net-next/master
>>
>
>I didn't test this, but it looks fine from my side.
>
>I agree with Grygorii, that if no comments, this should be re-sent as a
>patch series next.
Thanks, I'll do it on this week.

>
>
>> Ivan Khoronzhuk (6):
>>   net: ethernet: ti: cpsw: use cpdma channels in backward order for txq
>>   net: ethernet: ti: cpdma: fit rated channels in backward order
>>   net: ethernet: ti: cpsw: add MQPRIO Qdisc offload
>>   net: ethernet: ti: cpsw: add CBS Qdisc offload
>>   net: ethernet: ti: cpsw: restore shaper configuration while down/up
>>   Documentation: networking: cpsw: add MQPRIO & CBS offload examples
>>
>>  Documentation/networking/cpsw.txt       | 540 ++++++++++++++++++++++++
>>  drivers/net/ethernet/ti/cpsw.c          | 364 +++++++++++++++-
>>  drivers/net/ethernet/ti/davinci_cpdma.c |  31 +-
>>  3 files changed, 913 insertions(+), 22 deletions(-)
>>  create mode 100644 Documentation/networking/cpsw.txt
>>
>> --
>> 2.17.0
>
>
>Cheers,
>--
>Vinicius

-- 
Regards,
Ivan Khoronzhuk