[4/4] net: ethernet: ti: cpsw: add ethtool channels support
diff mbox

Message ID 1467313478-22919-5-git-send-email-ivan.khoronzhuk@linaro.org
State New
Headers show

Commit Message

Ivan Khoronzhuk June 30, 2016, 7:04 p.m. UTC
These ops allow to control number of channels driver is allowed to
work with. The maximum number of channels is 8 for rx and 8 for tx.
After this patch the following commands are possible:

$ ethtool -l eth0
$ ethtool -L eth0 rx 6 tx 6

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 188 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 188 insertions(+)

Comments

Grygorii Strashko July 8, 2016, 1:33 p.m. UTC | #1
On 06/30/2016 10:04 PM, Ivan Khoronzhuk wrote:
> These ops allow to control number of channels driver is allowed to
> work with. The maximum number of channels is 8 for rx and 8 for tx.
> After this patch the following commands are possible:
> 
> $ ethtool -l eth0
> $ ethtool -L eth0 rx 6 tx 6


Could you add some description here about switch vs dual_mac behavior? 

> 
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> ---
>   drivers/net/ethernet/ti/cpsw.c | 188 +++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 188 insertions(+)
> 
> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> index 595ed56..729b8be 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -740,6 +740,11 @@ static void cpsw_rx_handler(void *token, int len, int status)
>   	}
>   
>   requeue:
> +	if (netif_dormant(ndev)) {
> +		dev_kfree_skb_any(new_skb);
> +		return;
> +	}
> +
>   	ch = priv->rxch[skb_get_queue_mapping(new_skb)];
>   	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
>   				skb_tailroom(new_skb), 0);
> @@ -2077,6 +2082,187 @@ static void cpsw_ethtool_op_complete(struct net_device *ndev)
>   		cpsw_err(priv, drv, "ethtool complete failed %d\n", ret);
>   }
>   
> +static void cpsw_get_channels(struct net_device *dev,
> +			      struct ethtool_channels *ch)
> +{
> +	struct cpsw_priv *priv = netdev_priv(dev);
> +
> +	ch->max_combined = 0;
> +	ch->max_rx = CPSW_MAX_QUEUES;
> +	ch->max_tx = CPSW_MAX_QUEUES;
> +	ch->max_other = 0;
> +	ch->other_count = 0;
> +	ch->rx_count = priv->rx_ch_num;
> +	ch->tx_count = priv->tx_ch_num;
> +	ch->combined_count = 0;
> +}
> +
> +static int cpsw_check_ch_settings(struct cpsw_priv *priv,
> +				  struct ethtool_channels *ch)
> +{
> +	if (ch->combined_count)
> +		return -EINVAL;
> +
> +	/* verify we have at least one channel in each direction */
> +	if (!ch->rx_count || !ch->tx_count)
> +		return -EINVAL;
> +
> +	if (ch->rx_count > priv->data.channels ||
> +	    ch->tx_count > priv->data.channels)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static void cpsw_sync_dual_ch_list(struct net_device *sdev,
> +				   struct net_device *ddev)
> +{
> +	struct cpsw_priv *priv_s, *priv_d;
> +	int i;
> +
> +	priv_s = netdev_priv(sdev);
> +	priv_d = netdev_priv(ddev);
> +
> +	priv_d->rx_ch_num = priv_s->rx_ch_num;
> +	priv_d->tx_ch_num = priv_s->tx_ch_num;
> +
> +	for (i = 0; i < priv_d->tx_ch_num; i++)
> +		priv_d->txch[i] = priv_s->txch[i];
> +	for (i = 0; i < priv_d->rx_ch_num; i++)
> +		priv_d->rxch[i] = priv_s->rxch[i];
> +}
> +
> +static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
> +{
> +	int (*poll)(struct napi_struct *, int);
> +	void (*handler)(void *, int, int);
> +	struct cpdma_chan **chan;
> +	int *ch;
> +	int ret;
> +
> +	if (rx) {
> +		ch = &priv->rx_ch_num;
> +		chan = priv->rxch;
> +		handler = cpsw_rx_handler;
> +		poll = cpsw_rx_poll;
> +	} else {
> +		ch = &priv->tx_ch_num;
> +		chan = priv->txch;
> +		handler = cpsw_tx_handler;
> +		poll = cpsw_tx_poll;
> +	}
> +
> +	while (*ch < ch_num) {
> +		chan[*ch] = cpdma_chan_create(priv->dma, *ch, handler, rx);
> +
> +		if (IS_ERR(chan[*ch]))
> +			return PTR_ERR(chan[*ch]);
> +
> +		if (!chan[*ch])
> +			return -EINVAL;
> +
> +		dev_info(priv->dev, "created new %d %s channel\n", *ch,
> +			 (rx ? "rx" : "tx"));
> +		(*ch)++;
> +	}
> +
> +	while (*ch > ch_num) {
> +		int tch = *ch - 1;

why tch? can you use more informative names

> +
> +		ret = cpdma_chan_destroy(chan[tch]);
> +		if (ret)
> +			return ret;
> +
> +		dev_info(priv->dev, "destroyed %d %s channel\n", tch,
> +			 (rx ? "rx" : "tx"));
> +		(*ch)--;
> +	}
> +
> +	return 0;
> +}
> +
> +static int cpsw_update_channels(struct net_device *dev,
> +				struct ethtool_channels *ch)
> +{
> +	struct cpsw_priv *priv;
> +	int ret;
> +
> +	priv = netdev_priv(dev);
> +
> +	ret = cpsw_update_channels_res(priv, ch->rx_count, 1);
> +	if (ret)
> +		return ret;
> +
> +	ret = cpsw_update_channels_res(priv, ch->tx_count, 0);
> +	if (ret)
> +		return ret;
> +
> +	if (priv->data.dual_emac) {
> +		int i;
> +		/* mirror channels for another SL */
> +		for (i = 0; i < priv->data.slaves; i++) {
> +			if (priv->slaves[i].ndev == dev)
> +				continue;
> +
> +			cpsw_sync_dual_ch_list(dev, priv->slaves[i].ndev);
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int cpsw_set_channels(struct net_device *ndev,
> +			     struct ethtool_channels *chs)
> +{
> +	struct cpsw_priv *priv = netdev_priv(ndev);
> +	int ret;
> +
> +	ret = cpsw_check_ch_settings(priv, chs);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (netif_running(ndev)) {
> +		netif_tx_stop_all_queues(ndev);
> +		cpsw_intr_disable(priv);
> +		netif_dormant_on(ndev);
> +		cpdma_ctlr_stop(priv->dma);
> +	}
> +
> +	ret = cpsw_update_channels(ndev, chs);
> +	if (ret)
> +		goto err;
> +
> +	if (netif_running(ndev)) {
> +		/* inform stach about new count of queues */
> +		ret = netif_set_real_num_tx_queues(ndev, priv->tx_ch_num);
> +		if (ret) {
> +			dev_err(priv->dev, "cannot set real number of tx queues\n");
> +			goto err;
> +		}
> +
> +		ret = netif_set_real_num_rx_queues(ndev, priv->rx_ch_num);
> +		if (ret) {
> +			dev_err(priv->dev, "cannot set real number of rx queues\n");
> +			goto err;
> +		}

You're synchronizing slaves channels for dual_mac mode above, but updating netif real_num_XY_queues()
only for current netdev. Is it correct?

> +
> +		netif_dormant_off(ndev);
> +
> +		if (cpsw_fill_rx_channels(ndev))
> +			goto err;
> +
> +		cpdma_ctlr_start(priv->dma);
> +		cpsw_intr_enable(priv);
> +		netif_tx_start_all_queues(ndev);
> +	}
> +
> +	return 0;
> +err:
> +	dev_err(priv->dev, "cannot update channels number, closing device\n");
> +	dev_close(ndev);
> +	return ret;
> +}
> +
>   static const struct ethtool_ops cpsw_ethtool_ops = {
>   	.get_drvinfo	= cpsw_get_drvinfo,
>   	.get_msglevel	= cpsw_get_msglevel,
> @@ -2098,6 +2284,8 @@ static const struct ethtool_ops cpsw_ethtool_ops = {
>   	.get_regs	= cpsw_get_regs,
>   	.begin		= cpsw_ethtool_op_begin,
>   	.complete	= cpsw_ethtool_op_complete,
> +	.get_channels	= cpsw_get_channels,
> +	.set_channels	= cpsw_set_channels,
>   };
>   
>   static void cpsw_slave_init(struct cpsw_slave *slave, struct cpsw_priv *priv,
>
Ivan Khoronzhuk July 19, 2016, 1:39 p.m. UTC | #2
On 08.07.16 16:33, Grygorii Strashko wrote:
> On 06/30/2016 10:04 PM, Ivan Khoronzhuk wrote:
>> These ops allow to control number of channels driver is allowed to
>> work with. The maximum number of channels is 8 for rx and 8 for tx.
>> After this patch the following commands are possible:
>>
>> $ ethtool -l eth0
>> $ ethtool -L eth0 rx 6 tx 6
>
>
> Could you add some description here about switch vs dual_mac behavior?
I will add, but, maybe here should be some changes + info about how to share channels
between two interfaces. Would you like me to add some concrete description?

>
>>
>> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
>> ---
>>    drivers/net/ethernet/ti/cpsw.c | 188 +++++++++++++++++++++++++++++++++++++++++
>>    1 file changed, 188 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
>> index 595ed56..729b8be 100644
>> --- a/drivers/net/ethernet/ti/cpsw.c
>> +++ b/drivers/net/ethernet/ti/cpsw.c
>> @@ -740,6 +740,11 @@ static void cpsw_rx_handler(void *token, int len, int status)
>>    	}
>>
>>    requeue:
>> +	if (netif_dormant(ndev)) {
>> +		dev_kfree_skb_any(new_skb);
>> +		return;
>> +	}
>> +
>>    	ch = priv->rxch[skb_get_queue_mapping(new_skb)];
>>    	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
>>    				skb_tailroom(new_skb), 0);
>> @@ -2077,6 +2082,187 @@ static void cpsw_ethtool_op_complete(struct net_device *ndev)
>>    		cpsw_err(priv, drv, "ethtool complete failed %d\n", ret);
>>    }
>>
>> +static void cpsw_get_channels(struct net_device *dev,
>> +			      struct ethtool_channels *ch)
>> +{
>> +	struct cpsw_priv *priv = netdev_priv(dev);
>> +
>> +	ch->max_combined = 0;
>> +	ch->max_rx = CPSW_MAX_QUEUES;
>> +	ch->max_tx = CPSW_MAX_QUEUES;
>> +	ch->max_other = 0;
>> +	ch->other_count = 0;
>> +	ch->rx_count = priv->rx_ch_num;
>> +	ch->tx_count = priv->tx_ch_num;
>> +	ch->combined_count = 0;
>> +}
>> +
>> +static int cpsw_check_ch_settings(struct cpsw_priv *priv,
>> +				  struct ethtool_channels *ch)
>> +{
>> +	if (ch->combined_count)
>> +		return -EINVAL;
>> +
>> +	/* verify we have at least one channel in each direction */
>> +	if (!ch->rx_count || !ch->tx_count)
>> +		return -EINVAL;
>> +
>> +	if (ch->rx_count > priv->data.channels ||
>> +	    ch->tx_count > priv->data.channels)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static void cpsw_sync_dual_ch_list(struct net_device *sdev,
>> +				   struct net_device *ddev)
>> +{
>> +	struct cpsw_priv *priv_s, *priv_d;
>> +	int i;
>> +
>> +	priv_s = netdev_priv(sdev);
>> +	priv_d = netdev_priv(ddev);
>> +
>> +	priv_d->rx_ch_num = priv_s->rx_ch_num;
>> +	priv_d->tx_ch_num = priv_s->tx_ch_num;
>> +
>> +	for (i = 0; i < priv_d->tx_ch_num; i++)
>> +		priv_d->txch[i] = priv_s->txch[i];
>> +	for (i = 0; i < priv_d->rx_ch_num; i++)
>> +		priv_d->rxch[i] = priv_s->rxch[i];
>> +}
>> +
>> +static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
>> +{
>> +	int (*poll)(struct napi_struct *, int);
>> +	void (*handler)(void *, int, int);
>> +	struct cpdma_chan **chan;
>> +	int *ch;
>> +	int ret;
>> +
>> +	if (rx) {
>> +		ch = &priv->rx_ch_num;
>> +		chan = priv->rxch;
>> +		handler = cpsw_rx_handler;
>> +		poll = cpsw_rx_poll;
>> +	} else {
>> +		ch = &priv->tx_ch_num;
>> +		chan = priv->txch;
>> +		handler = cpsw_tx_handler;
>> +		poll = cpsw_tx_poll;
>> +	}
>> +
>> +	while (*ch < ch_num) {
>> +		chan[*ch] = cpdma_chan_create(priv->dma, *ch, handler, rx);
>> +
>> +		if (IS_ERR(chan[*ch]))
>> +			return PTR_ERR(chan[*ch]);
>> +
>> +		if (!chan[*ch])
>> +			return -EINVAL;
>> +
>> +		dev_info(priv->dev, "created new %d %s channel\n", *ch,
>> +			 (rx ? "rx" : "tx"));
>> +		(*ch)++;
>> +	}
>> +
>> +	while (*ch > ch_num) {
>> +		int tch = *ch - 1;
>
> why tch? can you use more informative names
Yep. Will correct.

>
>> +
>> +		ret = cpdma_chan_destroy(chan[tch]);
>> +		if (ret)
>> +			return ret;
>> +
>> +		dev_info(priv->dev, "destroyed %d %s channel\n", tch,
>> +			 (rx ? "rx" : "tx"));
>> +		(*ch)--;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int cpsw_update_channels(struct net_device *dev,
>> +				struct ethtool_channels *ch)
>> +{
>> +	struct cpsw_priv *priv;
>> +	int ret;
>> +
>> +	priv = netdev_priv(dev);
>> +
>> +	ret = cpsw_update_channels_res(priv, ch->rx_count, 1);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = cpsw_update_channels_res(priv, ch->tx_count, 0);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (priv->data.dual_emac) {
>> +		int i;
>> +		/* mirror channels for another SL */
>> +		for (i = 0; i < priv->data.slaves; i++) {
>> +			if (priv->slaves[i].ndev == dev)
>> +				continue;
>> +
>> +			cpsw_sync_dual_ch_list(dev, priv->slaves[i].ndev);
>> +		}
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int cpsw_set_channels(struct net_device *ndev,
>> +			     struct ethtool_channels *chs)
>> +{
>> +	struct cpsw_priv *priv = netdev_priv(ndev);
>> +	int ret;
>> +
>> +	ret = cpsw_check_ch_settings(priv, chs);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	if (netif_running(ndev)) {
>> +		netif_tx_stop_all_queues(ndev);
>> +		cpsw_intr_disable(priv);
>> +		netif_dormant_on(ndev);
>> +		cpdma_ctlr_stop(priv->dma);
>> +	}
>> +
>> +	ret = cpsw_update_channels(ndev, chs);
>> +	if (ret)
>> +		goto err;
>> +
>> +	if (netif_running(ndev)) {
>> +		/* inform stach about new count of queues */
>> +		ret = netif_set_real_num_tx_queues(ndev, priv->tx_ch_num);
>> +		if (ret) {
>> +			dev_err(priv->dev, "cannot set real number of tx queues\n");
>> +			goto err;
>> +		}
>> +
>> +		ret = netif_set_real_num_rx_queues(ndev, priv->rx_ch_num);
>> +		if (ret) {
>> +			dev_err(priv->dev, "cannot set real number of rx queues\n");
>> +			goto err;
>> +		}
>
> You're synchronizing slaves channels for dual_mac mode above, but updating netif real_num_XY_queues()
> only for current netdev. Is it correct?
It seems to be an issue. I'm going to change behavior for dual mode a little, and will keep it in mind.

>
>> +
>> +		netif_dormant_off(ndev);
>> +
>> +		if (cpsw_fill_rx_channels(ndev))
>> +			goto err;
>> +
>> +		cpdma_ctlr_start(priv->dma);
>> +		cpsw_intr_enable(priv);
>> +		netif_tx_start_all_queues(ndev);
>> +	}
>> +
>> +	return 0;
>> +err:
>> +	dev_err(priv->dev, "cannot update channels number, closing device\n");
>> +	dev_close(ndev);
>> +	return ret;
>> +}
>> +
>>    static const struct ethtool_ops cpsw_ethtool_ops = {
>>    	.get_drvinfo	= cpsw_get_drvinfo,
>>    	.get_msglevel	= cpsw_get_msglevel,
>> @@ -2098,6 +2284,8 @@ static const struct ethtool_ops cpsw_ethtool_ops = {
>>    	.get_regs	= cpsw_get_regs,
>>    	.begin		= cpsw_ethtool_op_begin,
>>    	.complete	= cpsw_ethtool_op_complete,
>> +	.get_channels	= cpsw_get_channels,
>> +	.set_channels	= cpsw_set_channels,
>>    };
>>
>>    static void cpsw_slave_init(struct cpsw_slave *slave, struct cpsw_priv *priv,
>>
>
>

Patch
diff mbox

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 595ed56..729b8be 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -740,6 +740,11 @@  static void cpsw_rx_handler(void *token, int len, int status)
 	}
 
 requeue:
+	if (netif_dormant(ndev)) {
+		dev_kfree_skb_any(new_skb);
+		return;
+	}
+
 	ch = priv->rxch[skb_get_queue_mapping(new_skb)];
 	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
 				skb_tailroom(new_skb), 0);
@@ -2077,6 +2082,187 @@  static void cpsw_ethtool_op_complete(struct net_device *ndev)
 		cpsw_err(priv, drv, "ethtool complete failed %d\n", ret);
 }
 
+static void cpsw_get_channels(struct net_device *dev,
+			      struct ethtool_channels *ch)
+{
+	struct cpsw_priv *priv = netdev_priv(dev);
+
+	ch->max_combined = 0;
+	ch->max_rx = CPSW_MAX_QUEUES;
+	ch->max_tx = CPSW_MAX_QUEUES;
+	ch->max_other = 0;
+	ch->other_count = 0;
+	ch->rx_count = priv->rx_ch_num;
+	ch->tx_count = priv->tx_ch_num;
+	ch->combined_count = 0;
+}
+
+static int cpsw_check_ch_settings(struct cpsw_priv *priv,
+				  struct ethtool_channels *ch)
+{
+	if (ch->combined_count)
+		return -EINVAL;
+
+	/* verify we have at least one channel in each direction */
+	if (!ch->rx_count || !ch->tx_count)
+		return -EINVAL;
+
+	if (ch->rx_count > priv->data.channels ||
+	    ch->tx_count > priv->data.channels)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void cpsw_sync_dual_ch_list(struct net_device *sdev,
+				   struct net_device *ddev)
+{
+	struct cpsw_priv *priv_s, *priv_d;
+	int i;
+
+	priv_s = netdev_priv(sdev);
+	priv_d = netdev_priv(ddev);
+
+	priv_d->rx_ch_num = priv_s->rx_ch_num;
+	priv_d->tx_ch_num = priv_s->tx_ch_num;
+
+	for (i = 0; i < priv_d->tx_ch_num; i++)
+		priv_d->txch[i] = priv_s->txch[i];
+	for (i = 0; i < priv_d->rx_ch_num; i++)
+		priv_d->rxch[i] = priv_s->rxch[i];
+}
+
+static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
+{
+	int (*poll)(struct napi_struct *, int);
+	void (*handler)(void *, int, int);
+	struct cpdma_chan **chan;
+	int *ch;
+	int ret;
+
+	if (rx) {
+		ch = &priv->rx_ch_num;
+		chan = priv->rxch;
+		handler = cpsw_rx_handler;
+		poll = cpsw_rx_poll;
+	} else {
+		ch = &priv->tx_ch_num;
+		chan = priv->txch;
+		handler = cpsw_tx_handler;
+		poll = cpsw_tx_poll;
+	}
+
+	while (*ch < ch_num) {
+		chan[*ch] = cpdma_chan_create(priv->dma, *ch, handler, rx);
+
+		if (IS_ERR(chan[*ch]))
+			return PTR_ERR(chan[*ch]);
+
+		if (!chan[*ch])
+			return -EINVAL;
+
+		dev_info(priv->dev, "created new %d %s channel\n", *ch,
+			 (rx ? "rx" : "tx"));
+		(*ch)++;
+	}
+
+	while (*ch > ch_num) {
+		int tch = *ch - 1;
+
+		ret = cpdma_chan_destroy(chan[tch]);
+		if (ret)
+			return ret;
+
+		dev_info(priv->dev, "destroyed %d %s channel\n", tch,
+			 (rx ? "rx" : "tx"));
+		(*ch)--;
+	}
+
+	return 0;
+}
+
+static int cpsw_update_channels(struct net_device *dev,
+				struct ethtool_channels *ch)
+{
+	struct cpsw_priv *priv;
+	int ret;
+
+	priv = netdev_priv(dev);
+
+	ret = cpsw_update_channels_res(priv, ch->rx_count, 1);
+	if (ret)
+		return ret;
+
+	ret = cpsw_update_channels_res(priv, ch->tx_count, 0);
+	if (ret)
+		return ret;
+
+	if (priv->data.dual_emac) {
+		int i;
+		/* mirror channels for another SL */
+		for (i = 0; i < priv->data.slaves; i++) {
+			if (priv->slaves[i].ndev == dev)
+				continue;
+
+			cpsw_sync_dual_ch_list(dev, priv->slaves[i].ndev);
+		}
+	}
+
+	return 0;
+}
+
+static int cpsw_set_channels(struct net_device *ndev,
+			     struct ethtool_channels *chs)
+{
+	struct cpsw_priv *priv = netdev_priv(ndev);
+	int ret;
+
+	ret = cpsw_check_ch_settings(priv, chs);
+	if (ret < 0)
+		return ret;
+
+	if (netif_running(ndev)) {
+		netif_tx_stop_all_queues(ndev);
+		cpsw_intr_disable(priv);
+		netif_dormant_on(ndev);
+		cpdma_ctlr_stop(priv->dma);
+	}
+
+	ret = cpsw_update_channels(ndev, chs);
+	if (ret)
+		goto err;
+
+	if (netif_running(ndev)) {
+		/* inform stach about new count of queues */
+		ret = netif_set_real_num_tx_queues(ndev, priv->tx_ch_num);
+		if (ret) {
+			dev_err(priv->dev, "cannot set real number of tx queues\n");
+			goto err;
+		}
+
+		ret = netif_set_real_num_rx_queues(ndev, priv->rx_ch_num);
+		if (ret) {
+			dev_err(priv->dev, "cannot set real number of rx queues\n");
+			goto err;
+		}
+
+		netif_dormant_off(ndev);
+
+		if (cpsw_fill_rx_channels(ndev))
+			goto err;
+
+		cpdma_ctlr_start(priv->dma);
+		cpsw_intr_enable(priv);
+		netif_tx_start_all_queues(ndev);
+	}
+
+	return 0;
+err:
+	dev_err(priv->dev, "cannot update channels number, closing device\n");
+	dev_close(ndev);
+	return ret;
+}
+
 static const struct ethtool_ops cpsw_ethtool_ops = {
 	.get_drvinfo	= cpsw_get_drvinfo,
 	.get_msglevel	= cpsw_get_msglevel,
@@ -2098,6 +2284,8 @@  static const struct ethtool_ops cpsw_ethtool_ops = {
 	.get_regs	= cpsw_get_regs,
 	.begin		= cpsw_ethtool_op_begin,
 	.complete	= cpsw_ethtool_op_complete,
+	.get_channels	= cpsw_get_channels,
+	.set_channels	= cpsw_set_channels,
 };
 
 static void cpsw_slave_init(struct cpsw_slave *slave, struct cpsw_priv *priv,