Commit a9e60cf0 authored by Grygorii Strashko's avatar Grygorii Strashko Committed by Jakub Kicinski
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net: ethernet: ti: am65-cpsw: prepare xmit/rx path for multi-port devices in mac-only mode 



This patch adds multi-port support to TI AM65x CPSW driver xmit/rx path in
preparation for adding support for multi-port devices, like Main CPSW0 on
K3 J721E SoC or future CPSW3g on K3 AM64x SoC.
Hence DMA channels are common/shared for all ext Ports and the RX/TX NAPI
and DMA processing going to be assigned to first available netdev this patch:
 - ensures all RX descriptors fields are initialized;
 - adds synchronization for TX DMA push/pop operation (locking) as
Networking core locks are not enough any more;
 - updates TX bql processing for every packet in
am65_cpsw_nuss_tx_compl_packets() as every completed TX skb can have
different ndev assigned (come from different netdevs).

To avoid performance issues for existing one-port CPSW2g devices the above
changes are done only for multi-port devices by splitting xmit path for
one-port and multi-port devices.

Signed-off-by: default avatarGrygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: default avatarJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 97067aaf

drivers/net/ethernet/ti/am65-cpsw-nuss.c

+107 −34
Original line number Diff line number Diff line
@@ -375,7 +375,7 @@ static int am65_cpsw_nuss_rx_push(struct am65_cpsw_common *common, 


	cppi5_hdesc_init(desc_rx, CPPI5_INFO0_HDESC_EPIB_PRESENT,

			 AM65_CPSW_NAV_PS_DATA_SIZE);

	cppi5_hdesc_attach_buf(desc_rx, 0, 0, buf_dma, skb_tailroom(skb));

	cppi5_hdesc_attach_buf(desc_rx, buf_dma, skb_tailroom(skb), buf_dma, skb_tailroom(skb));

	swdata = cppi5_hdesc_get_swdata(desc_rx);

	*((void **)swdata) = skb;
@@ -911,10 +911,57 @@ static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma) 
	dev_kfree_skb_any(skb);

}



static struct sk_buff *

am65_cpsw_nuss_tx_compl_packet(struct am65_cpsw_tx_chn *tx_chn,

			       dma_addr_t desc_dma)

{

	struct am65_cpsw_ndev_priv *ndev_priv;

	struct am65_cpsw_ndev_stats *stats;

	struct cppi5_host_desc_t *desc_tx;

	struct net_device *ndev;

	struct sk_buff *skb;

	void **swdata;



	desc_tx = k3_cppi_desc_pool_dma2virt(tx_chn->desc_pool,

					     desc_dma);

	swdata = cppi5_hdesc_get_swdata(desc_tx);

	skb = *(swdata);

	am65_cpsw_nuss_xmit_free(tx_chn, tx_chn->common->dev, desc_tx);



	ndev = skb->dev;



	am65_cpts_tx_timestamp(tx_chn->common->cpts, skb);



	ndev_priv = netdev_priv(ndev);

	stats = this_cpu_ptr(ndev_priv->stats);

	u64_stats_update_begin(&stats->syncp);

	stats->tx_packets++;

	stats->tx_bytes += skb->len;

	u64_stats_update_end(&stats->syncp);



	return skb;

}



static void am65_cpsw_nuss_tx_wake(struct am65_cpsw_tx_chn *tx_chn, struct net_device *ndev,

				   struct netdev_queue *netif_txq)

{

	if (netif_tx_queue_stopped(netif_txq)) {

		/* Check whether the queue is stopped due to stalled

		 * tx dma, if the queue is stopped then wake the queue

		 * as we have free desc for tx

		 */

		__netif_tx_lock(netif_txq, smp_processor_id());

		if (netif_running(ndev) &&

		    (k3_cppi_desc_pool_avail(tx_chn->desc_pool) >= MAX_SKB_FRAGS))

			netif_tx_wake_queue(netif_txq);



		__netif_tx_unlock(netif_txq);

	}

}



static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,

					   int chn, unsigned int budget)

{

	struct cppi5_host_desc_t *desc_tx;

	struct device *dev = common->dev;

	struct am65_cpsw_tx_chn *tx_chn;

	struct netdev_queue *netif_txq;
@@ -923,15 +970,13 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common, 
	struct sk_buff *skb;

	dma_addr_t desc_dma;

	int res, num_tx = 0;

	void **swdata;



	tx_chn = &common->tx_chns[chn];



	while (true) {

		struct am65_cpsw_ndev_priv *ndev_priv;

		struct am65_cpsw_ndev_stats *stats;



		spin_lock(&tx_chn->lock);

		res = k3_udma_glue_pop_tx_chn(tx_chn->tx_chn, &desc_dma);

		spin_unlock(&tx_chn->lock);

		if (res == -ENODATA)

			break;
@@ -941,23 +986,52 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common, 
			break;

		}



		desc_tx = k3_cppi_desc_pool_dma2virt(tx_chn->desc_pool,

						     desc_dma);

		swdata = cppi5_hdesc_get_swdata(desc_tx);

		skb = *(swdata);

		am65_cpsw_nuss_xmit_free(tx_chn, dev, desc_tx);



		skb = am65_cpsw_nuss_tx_compl_packet(tx_chn, desc_dma);

		total_bytes = skb->len;

		ndev = skb->dev;

		napi_consume_skb(skb, budget);

		num_tx++;



		am65_cpts_tx_timestamp(common->cpts, skb);

		netif_txq = netdev_get_tx_queue(ndev, chn);



		ndev_priv = netdev_priv(ndev);

		stats = this_cpu_ptr(ndev_priv->stats);

		u64_stats_update_begin(&stats->syncp);

		stats->tx_packets++;

		stats->tx_bytes += skb->len;

		u64_stats_update_end(&stats->syncp);

		netdev_tx_completed_queue(netif_txq, num_tx, total_bytes);



		am65_cpsw_nuss_tx_wake(tx_chn, ndev, netif_txq);

	}



	dev_dbg(dev, "%s:%u pkt:%d\n", __func__, chn, num_tx);



	return num_tx;

}



static int am65_cpsw_nuss_tx_compl_packets_2g(struct am65_cpsw_common *common,

					      int chn, unsigned int budget)

{

	struct device *dev = common->dev;

	struct am65_cpsw_tx_chn *tx_chn;

	struct netdev_queue *netif_txq;

	unsigned int total_bytes = 0;

	struct net_device *ndev;

	struct sk_buff *skb;

	dma_addr_t desc_dma;

	int res, num_tx = 0;



	tx_chn = &common->tx_chns[chn];



	while (true) {

		res = k3_udma_glue_pop_tx_chn(tx_chn->tx_chn, &desc_dma);

		if (res == -ENODATA)

			break;



		if (cppi5_desc_is_tdcm(desc_dma)) {

			if (atomic_dec_and_test(&common->tdown_cnt))

				complete(&common->tdown_complete);

			break;

		}



		skb = am65_cpsw_nuss_tx_compl_packet(tx_chn, desc_dma);



		ndev = skb->dev;

		total_bytes += skb->len;

		napi_consume_skb(skb, budget);

		num_tx++;
@@ -970,19 +1044,8 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common, 


	netdev_tx_completed_queue(netif_txq, num_tx, total_bytes);



	if (netif_tx_queue_stopped(netif_txq)) {

		/* Check whether the queue is stopped due to stalled tx dma,

		 * if the queue is stopped then wake the queue as

		 * we have free desc for tx

		 */

		__netif_tx_lock(netif_txq, smp_processor_id());

		if (netif_running(ndev) &&

		    (k3_cppi_desc_pool_avail(tx_chn->desc_pool) >=

		     MAX_SKB_FRAGS))

			netif_tx_wake_queue(netif_txq);

	am65_cpsw_nuss_tx_wake(tx_chn, ndev, netif_txq);



		__netif_tx_unlock(netif_txq);

	}

	dev_dbg(dev, "%s:%u pkt:%d\n", __func__, chn, num_tx);



	return num_tx;
@@ -993,8 +1056,11 @@ static int am65_cpsw_nuss_tx_poll(struct napi_struct *napi_tx, int budget) 
	struct am65_cpsw_tx_chn *tx_chn = am65_cpsw_napi_to_tx_chn(napi_tx);

	int num_tx;



	num_tx = am65_cpsw_nuss_tx_compl_packets(tx_chn->common, tx_chn->id,

						 budget);

	if (AM65_CPSW_IS_CPSW2G(tx_chn->common))

		num_tx = am65_cpsw_nuss_tx_compl_packets_2g(tx_chn->common, tx_chn->id, budget);

	else

		num_tx = am65_cpsw_nuss_tx_compl_packets(tx_chn->common, tx_chn->id, budget);



	num_tx = min(num_tx, budget);

	if (num_tx < budget) {

		napi_complete(napi_tx);
@@ -1139,7 +1205,13 @@ static netdev_tx_t am65_cpsw_nuss_ndo_slave_xmit(struct sk_buff *skb, 


	cppi5_hdesc_set_pktlen(first_desc, pkt_len);

	desc_dma = k3_cppi_desc_pool_virt2dma(tx_chn->desc_pool, first_desc);

	if (AM65_CPSW_IS_CPSW2G(common)) {

		ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn, first_desc, desc_dma);

	} else {

		spin_lock_bh(&tx_chn->lock);

		ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn, first_desc, desc_dma);

		spin_unlock_bh(&tx_chn->lock);

	}

	if (ret) {

		dev_err(dev, "can't push desc %d\n", ret);

		/* inform bql */
@@ -1470,6 +1542,7 @@ static int am65_cpsw_nuss_init_tx_chns(struct am65_cpsw_common *common) 
		snprintf(tx_chn->tx_chn_name,

			 sizeof(tx_chn->tx_chn_name), "tx%d", i);



		spin_lock_init(&tx_chn->lock);

		tx_chn->common = common;

		tx_chn->id = i;

		tx_chn->descs_num = max_desc_num;

drivers/net/ethernet/ti/am65-cpsw-nuss.h

+1 −0
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ struct am65_cpsw_tx_chn { 
	struct am65_cpsw_common	*common;

	struct k3_cppi_desc_pool *desc_pool;

	struct k3_udma_glue_tx_channel *tx_chn;

	spinlock_t lock; /* protect TX rings in multi-port mode */

	int irq;

	u32 id;

	u32 descs_num;