[v3,5/5] net: ethernet: ti: cpsw: add ethtool channels support
diff mbox

Message ID 1471303549-4134-6-git-send-email-ivan.khoronzhuk@linaro.org
State New
Headers show

Commit Message

Ivan Khoronzhuk Aug. 15, 2016, 11:25 p.m. UTC
These ops allow to control number of channels driver is allowed to
work with at cpdma level. The maximum number of channels is 8 for
rx and 8 for tx. In dual_emac mode the h/w channels are shared
between two interfaces and changing number on one interface changes
number of channels on another.

How many channels are supported and enabled:
$ ethtool -l ethX

Change number of channels (up to 8)
$ ethtool -L ethX rx 6 tx 6

Per-channel statistic:
$ ethtool -S ethX

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
---
 drivers/net/ethernet/ti/cpsw.c | 180 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 176 insertions(+), 4 deletions(-)

Comments

Mugunthan V N Aug. 17, 2016, 6:22 a.m. UTC | #1
On Tuesday 16 August 2016 04:55 AM, Ivan Khoronzhuk wrote:
> These ops allow to control number of channels driver is allowed to
> work with at cpdma level. The maximum number of channels is 8 for
> rx and 8 for tx. In dual_emac mode the h/w channels are shared
> between two interfaces and changing number on one interface changes
> number of channels on another.
> 
> How many channels are supported and enabled:
> $ ethtool -l ethX
> 
> Change number of channels (up to 8)
> $ ethtool -L ethX rx 6 tx 6
> 
> Per-channel statistic:
> $ ethtool -S ethX
> 
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> ---
>  drivers/net/ethernet/ti/cpsw.c | 180 ++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 176 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> index 6dcbd8a..f02e577 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -735,6 +735,11 @@ static void cpsw_rx_handler(void *token, int len, int status)
>  	}
>  
>  requeue:
> +	if (netif_dormant(ndev)) {
> +		dev_kfree_skb_any(new_skb);
> +		return;
> +	}
> +
>  	ch = cpsw->rxch[skb_get_queue_mapping(new_skb)];
>  	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
>  				skb_tailroom(new_skb), 0);
> @@ -1267,9 +1272,8 @@ static void cpsw_init_host_port(struct cpsw_priv *priv)
>  	}
>  }
>  
> -static int cpsw_fill_rx_channels(struct net_device *ndev)
> +static int cpsw_fill_rx_channels(struct cpsw_priv *priv)

This change can be moved to patch 1/5 where the function definition is
added at first.

>  {
> -	struct cpsw_priv *priv = netdev_priv(ndev);
>  	struct cpsw_common *cpsw = priv->cpsw;
>  	struct sk_buff *skb;
>  	int ch, i, ret;
> @@ -1279,7 +1283,7 @@ static int cpsw_fill_rx_channels(struct net_device *ndev)
>  
>  		ch_buf_num = cpdma_chan_get_rx_buf_num(cpsw->rxch[ch]);
>  		for (i = 0; i < ch_buf_num; i++) {
> -			skb = __netdev_alloc_skb_ip_align(ndev,
> +			skb = __netdev_alloc_skb_ip_align(priv->ndev,
>  							  cpsw->rx_packet_max,
>  							  GFP_KERNEL);
>  			if (!skb) {
> @@ -1397,7 +1401,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
>  			enable_irq(cpsw->irqs_table[0]);
>  		}
>  
> -		ret = cpsw_fill_rx_channels(ndev);
> +		ret = cpsw_fill_rx_channels(priv);
>  		if (ret < 0)
>  			goto err_cleanup;
>  
> @@ -2060,6 +2064,172 @@ 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 *ndev,
> +			      struct ethtool_channels *ch)
> +{
> +	struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
> +
> +	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 = cpsw->rx_ch_num;
> +	ch->tx_count = cpsw->tx_ch_num;
> +	ch->combined_count = 0;
> +}
> +
> +static int cpsw_check_ch_settings(struct cpsw_common *cpsw,
> +				  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 > cpsw->data.channels ||
> +	    ch->tx_count > cpsw->data.channels)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
> +{
> +	int (*poll)(struct napi_struct *, int);
> +	struct cpsw_common *cpsw = priv->cpsw;
> +	void (*handler)(void *, int, int);
> +	struct cpdma_chan **chan;
> +	int ret, *ch;
> +
> +	if (rx) {
> +		ch = &cpsw->rx_ch_num;
> +		chan = cpsw->rxch;
> +		handler = cpsw_rx_handler;
> +		poll = cpsw_rx_poll;
> +	} else {
> +		ch = &cpsw->tx_ch_num;
> +		chan = cpsw->txch;
> +		handler = cpsw_tx_handler;
> +		poll = cpsw_tx_poll;
> +	}
> +
> +	while (*ch < ch_num) {
> +		chan[*ch] = cpdma_chan_create(cpsw->dma, *ch, handler, rx);
> +
> +		if (IS_ERR(chan[*ch]))
> +			return PTR_ERR(chan[*ch]);
> +
> +		if (!chan[*ch])
> +			return -EINVAL;
> +
> +		cpsw_info(priv, ifup, "created new %d %s channel\n", *ch,
> +			  (rx ? "rx" : "tx"));
> +		(*ch)++;
> +	}
> +
> +	while (*ch > ch_num) {
> +		(*ch)--;
> +
> +		ret = cpdma_chan_destroy(chan[*ch]);
> +		if (ret)
> +			return ret;
> +
> +		cpsw_info(priv, ifup, "destroyed %d %s channel\n", *ch,
> +			  (rx ? "rx" : "tx"));
> +	}
> +
> +	return 0;
> +}
> +
> +static int cpsw_update_channels(struct cpsw_priv *priv,
> +				struct ethtool_channels *ch)
> +{
> +	int ret;
> +
> +	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;
> +
> +	return 0;
> +}
> +
> +static int cpsw_set_channels(struct net_device *ndev,
> +			     struct ethtool_channels *chs)
> +{
> +	struct cpsw_priv *priv = netdev_priv(ndev);
> +	struct cpsw_common *cpsw = priv->cpsw;
> +	struct cpsw_slave *slave;
> +	int i, ret;
> +
> +	ret = cpsw_check_ch_settings(cpsw, chs);
> +	if (ret < 0)
> +		return ret;
> +
> +	cpsw_intr_disable(cpsw);
> +
> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
> +		if (!(slave->ndev && netif_running(slave->ndev)))
> +			continue;
> +
> +		netif_tx_stop_all_queues(slave->ndev);
> +		netif_dormant_on(slave->ndev);
> +	}
> +
> +	cpdma_ctlr_stop(cpsw->dma);
> +	ret = cpsw_update_channels(priv, chs);
> +	if (ret)
> +		goto err;
> +
> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
> +		if (!(slave->ndev && netif_running(slave->ndev)))
> +			continue;
> +
> +		/* inform stack about new count of queues */
> +		ret = netif_set_real_num_tx_queues(slave->ndev,
> +						   cpsw->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(slave->ndev,
> +						   cpsw->rx_ch_num);
> +		if (ret) {
> +			dev_err(priv->dev, "cannot set real number of rx queues\n");
> +			goto err;
> +		}
> +
> +		netif_dormant_off(slave->ndev);
> +	}
> +
> +	if (cpsw_common_res_usage_state(cpsw)) {
> +		if (cpsw_fill_rx_channels(priv))
> +			goto err;
> +
> +		cpdma_ctlr_start(cpsw->dma);
> +		cpsw_intr_enable(cpsw);
> +	}
> +
> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
> +		if (!(slave->ndev && netif_running(slave->ndev)))
> +			continue;
> +		netif_tx_start_all_queues(slave->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,
> @@ -2081,6 +2251,8 @@ 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_common *cpsw,
> 

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Ivan Khoronzhuk Aug. 17, 2016, 7:22 a.m. UTC | #2
On 17.08.16 09:22, Mugunthan V N wrote:
> On Tuesday 16 August 2016 04:55 AM, Ivan Khoronzhuk wrote:
>> These ops allow to control number of channels driver is allowed to
>> work with at cpdma level. The maximum number of channels is 8 for
>> rx and 8 for tx. In dual_emac mode the h/w channels are shared
>> between two interfaces and changing number on one interface changes
>> number of channels on another.
>>
>> How many channels are supported and enabled:
>> $ ethtool -l ethX
>>
>> Change number of channels (up to 8)
>> $ ethtool -L ethX rx 6 tx 6
>>
>> Per-channel statistic:
>> $ ethtool -S ethX
>>
>> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
>> ---
>>  drivers/net/ethernet/ti/cpsw.c | 180 ++++++++++++++++++++++++++++++++++++++++-
>>  1 file changed, 176 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
>> index 6dcbd8a..f02e577 100644
>> --- a/drivers/net/ethernet/ti/cpsw.c
>> +++ b/drivers/net/ethernet/ti/cpsw.c
>> @@ -735,6 +735,11 @@ static void cpsw_rx_handler(void *token, int len, int status)
>>  	}
>>
>>  requeue:
>> +	if (netif_dormant(ndev)) {
>> +		dev_kfree_skb_any(new_skb);
>> +		return;
>> +	}
>> +
>>  	ch = cpsw->rxch[skb_get_queue_mapping(new_skb)];
>>  	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
>>  				skb_tailroom(new_skb), 0);
>> @@ -1267,9 +1272,8 @@ static void cpsw_init_host_port(struct cpsw_priv *priv)
>>  	}
>>  }
>>
>> -static int cpsw_fill_rx_channels(struct net_device *ndev)
>> +static int cpsw_fill_rx_channels(struct cpsw_priv *priv)
>
> This change can be moved to patch 1/5 where the function definition is
> added at first.
Yes. Will do it in v4.

>
>>  {
>> -	struct cpsw_priv *priv = netdev_priv(ndev);
>>  	struct cpsw_common *cpsw = priv->cpsw;
>>  	struct sk_buff *skb;
>>  	int ch, i, ret;
>> @@ -1279,7 +1283,7 @@ static int cpsw_fill_rx_channels(struct net_device *ndev)
>>
>>  		ch_buf_num = cpdma_chan_get_rx_buf_num(cpsw->rxch[ch]);
>>  		for (i = 0; i < ch_buf_num; i++) {
>> -			skb = __netdev_alloc_skb_ip_align(ndev,
>> +			skb = __netdev_alloc_skb_ip_align(priv->ndev,
>>  							  cpsw->rx_packet_max,
>>  							  GFP_KERNEL);
>>  			if (!skb) {
>> @@ -1397,7 +1401,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
>>  			enable_irq(cpsw->irqs_table[0]);
>>  		}
>>
>> -		ret = cpsw_fill_rx_channels(ndev);
>> +		ret = cpsw_fill_rx_channels(priv);
>>  		if (ret < 0)
>>  			goto err_cleanup;
>>
>> @@ -2060,6 +2064,172 @@ 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 *ndev,
>> +			      struct ethtool_channels *ch)
>> +{
>> +	struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>> +
>> +	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 = cpsw->rx_ch_num;
>> +	ch->tx_count = cpsw->tx_ch_num;
>> +	ch->combined_count = 0;
>> +}
>> +
>> +static int cpsw_check_ch_settings(struct cpsw_common *cpsw,
>> +				  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 > cpsw->data.channels ||
>> +	    ch->tx_count > cpsw->data.channels)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
>> +{
>> +	int (*poll)(struct napi_struct *, int);
>> +	struct cpsw_common *cpsw = priv->cpsw;
>> +	void (*handler)(void *, int, int);
>> +	struct cpdma_chan **chan;
>> +	int ret, *ch;
>> +
>> +	if (rx) {
>> +		ch = &cpsw->rx_ch_num;
>> +		chan = cpsw->rxch;
>> +		handler = cpsw_rx_handler;
>> +		poll = cpsw_rx_poll;
>> +	} else {
>> +		ch = &cpsw->tx_ch_num;
>> +		chan = cpsw->txch;
>> +		handler = cpsw_tx_handler;
>> +		poll = cpsw_tx_poll;
>> +	}
>> +
>> +	while (*ch < ch_num) {
>> +		chan[*ch] = cpdma_chan_create(cpsw->dma, *ch, handler, rx);
>> +
>> +		if (IS_ERR(chan[*ch]))
>> +			return PTR_ERR(chan[*ch]);
>> +
>> +		if (!chan[*ch])
>> +			return -EINVAL;
>> +
>> +		cpsw_info(priv, ifup, "created new %d %s channel\n", *ch,
>> +			  (rx ? "rx" : "tx"));
>> +		(*ch)++;
>> +	}
>> +
>> +	while (*ch > ch_num) {
>> +		(*ch)--;
>> +
>> +		ret = cpdma_chan_destroy(chan[*ch]);
>> +		if (ret)
>> +			return ret;
>> +
>> +		cpsw_info(priv, ifup, "destroyed %d %s channel\n", *ch,
>> +			  (rx ? "rx" : "tx"));
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int cpsw_update_channels(struct cpsw_priv *priv,
>> +				struct ethtool_channels *ch)
>> +{
>> +	int ret;
>> +
>> +	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;
>> +
>> +	return 0;
>> +}
>> +
>> +static int cpsw_set_channels(struct net_device *ndev,
>> +			     struct ethtool_channels *chs)
>> +{
>> +	struct cpsw_priv *priv = netdev_priv(ndev);
>> +	struct cpsw_common *cpsw = priv->cpsw;
>> +	struct cpsw_slave *slave;
>> +	int i, ret;
>> +
>> +	ret = cpsw_check_ch_settings(cpsw, chs);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	cpsw_intr_disable(cpsw);
>> +
>> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
>> +		if (!(slave->ndev && netif_running(slave->ndev)))
>> +			continue;
>> +
>> +		netif_tx_stop_all_queues(slave->ndev);
>> +		netif_dormant_on(slave->ndev);
>> +	}
>> +
>> +	cpdma_ctlr_stop(cpsw->dma);
>> +	ret = cpsw_update_channels(priv, chs);
>> +	if (ret)
>> +		goto err;
>> +
>> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
>> +		if (!(slave->ndev && netif_running(slave->ndev)))
>> +			continue;
>> +
>> +		/* inform stack about new count of queues */
>> +		ret = netif_set_real_num_tx_queues(slave->ndev,
>> +						   cpsw->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(slave->ndev,
>> +						   cpsw->rx_ch_num);
>> +		if (ret) {
>> +			dev_err(priv->dev, "cannot set real number of rx queues\n");
>> +			goto err;
>> +		}
>> +
>> +		netif_dormant_off(slave->ndev);
>> +	}
>> +
>> +	if (cpsw_common_res_usage_state(cpsw)) {
>> +		if (cpsw_fill_rx_channels(priv))
>> +			goto err;
>> +
>> +		cpdma_ctlr_start(cpsw->dma);
>> +		cpsw_intr_enable(cpsw);
>> +	}
>> +
>> +	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
>> +		if (!(slave->ndev && netif_running(slave->ndev)))
>> +			continue;
>> +		netif_tx_start_all_queues(slave->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,
>> @@ -2081,6 +2251,8 @@ 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_common *cpsw,
>>
>
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Patch
diff mbox

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 6dcbd8a..f02e577 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -735,6 +735,11 @@  static void cpsw_rx_handler(void *token, int len, int status)
 	}
 
 requeue:
+	if (netif_dormant(ndev)) {
+		dev_kfree_skb_any(new_skb);
+		return;
+	}
+
 	ch = cpsw->rxch[skb_get_queue_mapping(new_skb)];
 	ret = cpdma_chan_submit(ch, new_skb, new_skb->data,
 				skb_tailroom(new_skb), 0);
@@ -1267,9 +1272,8 @@  static void cpsw_init_host_port(struct cpsw_priv *priv)
 	}
 }
 
-static int cpsw_fill_rx_channels(struct net_device *ndev)
+static int cpsw_fill_rx_channels(struct cpsw_priv *priv)
 {
-	struct cpsw_priv *priv = netdev_priv(ndev);
 	struct cpsw_common *cpsw = priv->cpsw;
 	struct sk_buff *skb;
 	int ch, i, ret;
@@ -1279,7 +1283,7 @@  static int cpsw_fill_rx_channels(struct net_device *ndev)
 
 		ch_buf_num = cpdma_chan_get_rx_buf_num(cpsw->rxch[ch]);
 		for (i = 0; i < ch_buf_num; i++) {
-			skb = __netdev_alloc_skb_ip_align(ndev,
+			skb = __netdev_alloc_skb_ip_align(priv->ndev,
 							  cpsw->rx_packet_max,
 							  GFP_KERNEL);
 			if (!skb) {
@@ -1397,7 +1401,7 @@  static int cpsw_ndo_open(struct net_device *ndev)
 			enable_irq(cpsw->irqs_table[0]);
 		}
 
-		ret = cpsw_fill_rx_channels(ndev);
+		ret = cpsw_fill_rx_channels(priv);
 		if (ret < 0)
 			goto err_cleanup;
 
@@ -2060,6 +2064,172 @@  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 *ndev,
+			      struct ethtool_channels *ch)
+{
+	struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
+
+	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 = cpsw->rx_ch_num;
+	ch->tx_count = cpsw->tx_ch_num;
+	ch->combined_count = 0;
+}
+
+static int cpsw_check_ch_settings(struct cpsw_common *cpsw,
+				  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 > cpsw->data.channels ||
+	    ch->tx_count > cpsw->data.channels)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int cpsw_update_channels_res(struct cpsw_priv *priv, int ch_num, int rx)
+{
+	int (*poll)(struct napi_struct *, int);
+	struct cpsw_common *cpsw = priv->cpsw;
+	void (*handler)(void *, int, int);
+	struct cpdma_chan **chan;
+	int ret, *ch;
+
+	if (rx) {
+		ch = &cpsw->rx_ch_num;
+		chan = cpsw->rxch;
+		handler = cpsw_rx_handler;
+		poll = cpsw_rx_poll;
+	} else {
+		ch = &cpsw->tx_ch_num;
+		chan = cpsw->txch;
+		handler = cpsw_tx_handler;
+		poll = cpsw_tx_poll;
+	}
+
+	while (*ch < ch_num) {
+		chan[*ch] = cpdma_chan_create(cpsw->dma, *ch, handler, rx);
+
+		if (IS_ERR(chan[*ch]))
+			return PTR_ERR(chan[*ch]);
+
+		if (!chan[*ch])
+			return -EINVAL;
+
+		cpsw_info(priv, ifup, "created new %d %s channel\n", *ch,
+			  (rx ? "rx" : "tx"));
+		(*ch)++;
+	}
+
+	while (*ch > ch_num) {
+		(*ch)--;
+
+		ret = cpdma_chan_destroy(chan[*ch]);
+		if (ret)
+			return ret;
+
+		cpsw_info(priv, ifup, "destroyed %d %s channel\n", *ch,
+			  (rx ? "rx" : "tx"));
+	}
+
+	return 0;
+}
+
+static int cpsw_update_channels(struct cpsw_priv *priv,
+				struct ethtool_channels *ch)
+{
+	int ret;
+
+	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;
+
+	return 0;
+}
+
+static int cpsw_set_channels(struct net_device *ndev,
+			     struct ethtool_channels *chs)
+{
+	struct cpsw_priv *priv = netdev_priv(ndev);
+	struct cpsw_common *cpsw = priv->cpsw;
+	struct cpsw_slave *slave;
+	int i, ret;
+
+	ret = cpsw_check_ch_settings(cpsw, chs);
+	if (ret < 0)
+		return ret;
+
+	cpsw_intr_disable(cpsw);
+
+	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
+		if (!(slave->ndev && netif_running(slave->ndev)))
+			continue;
+
+		netif_tx_stop_all_queues(slave->ndev);
+		netif_dormant_on(slave->ndev);
+	}
+
+	cpdma_ctlr_stop(cpsw->dma);
+	ret = cpsw_update_channels(priv, chs);
+	if (ret)
+		goto err;
+
+	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
+		if (!(slave->ndev && netif_running(slave->ndev)))
+			continue;
+
+		/* inform stack about new count of queues */
+		ret = netif_set_real_num_tx_queues(slave->ndev,
+						   cpsw->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(slave->ndev,
+						   cpsw->rx_ch_num);
+		if (ret) {
+			dev_err(priv->dev, "cannot set real number of rx queues\n");
+			goto err;
+		}
+
+		netif_dormant_off(slave->ndev);
+	}
+
+	if (cpsw_common_res_usage_state(cpsw)) {
+		if (cpsw_fill_rx_channels(priv))
+			goto err;
+
+		cpdma_ctlr_start(cpsw->dma);
+		cpsw_intr_enable(cpsw);
+	}
+
+	for (i = cpsw->data.slaves, slave = cpsw->slaves; i; i--, slave++) {
+		if (!(slave->ndev && netif_running(slave->ndev)))
+			continue;
+		netif_tx_start_all_queues(slave->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,
@@ -2081,6 +2251,8 @@  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_common *cpsw,