cns3xxx: fix ethernet jumbo-frame support, use single-page rx buffers and skb fragment lists

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@33491 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 317 insertions, 0 deletions

diff --git a/target/linux/cns3xxx/patches-3.3/410-ethernet_fix_jumbo_frame.patch b/target/linux/cns3xxx/patches-3.3/410-ethernet_fix_jumbo_frame.patch
new file mode 100644
index 000000000..268770ffb
--- /dev/null
+++ b/target/linux/cns3xxx/patches-3.3/410-ethernet_fix_jumbo_frame.patch
@@ -0,0 +1,317 @@
+--- a/drivers/net/ethernet/cavium/cns3xxx_eth.c
++++ b/drivers/net/ethernet/cavium/cns3xxx_eth.c
+@@ -26,15 +26,18 @@
+ 
+ #define DRV_NAME "cns3xxx_eth"
+ 
+-#define RX_DESCS 512
+-#define TX_DESCS 512
+-#define SKB_DMA_REALIGN ((PAGE_SIZE - NET_SKB_PAD) % SMP_CACHE_BYTES)
++#define RX_DESCS 128
++#define TX_DESCS 128
+ 
+ #define RX_POOL_ALLOC_SIZE (sizeof(struct rx_desc) * RX_DESCS)
+ #define TX_POOL_ALLOC_SIZE (sizeof(struct tx_desc) * TX_DESCS)
+ #define REGS_SIZE 336
+-#define MAX_MRU (1536 + SKB_DMA_REALIGN)
+-#define CNS3XXX_MAX_MTU (1536)
++
++#define SKB_HEAD_ALIGN (((PAGE_SIZE - NET_SKB_PAD) % SMP_CACHE_BYTES) + NET_SKB_PAD + NET_IP_ALIGN)
++#define RX_SEGMENT_ALLOC_SIZE 4096
++#define RX_SEGMENT_BUFSIZE (SKB_WITH_OVERHEAD(RX_SEGMENT_ALLOC_SIZE))
++#define RX_SEGMENT_MRU ((RX_SEGMENT_BUFSIZE - SKB_HEAD_ALIGN))
++#define MAX_MTU	9500
+ 
+ #define NAPI_WEIGHT 64
+ 
+@@ -266,7 +269,7 @@ struct _rx_ring {
+ 	struct rx_desc *desc;
+ 	dma_addr_t phys_addr;
+ 	struct rx_desc *cur_addr;
+-	struct sk_buff *buff_tab[RX_DESCS];
++	void *buff_tab[RX_DESCS];
+ 	unsigned int phys_tab[RX_DESCS];
+ 	u32 cur_index;
+ 	u32 alloc_index;
+@@ -280,6 +283,8 @@ struct sw {
+ 	struct cns3xxx_plat_info *plat;
+ 	struct _tx_ring *tx_ring;
+ 	struct _rx_ring *rx_ring;
++	struct sk_buff *frag_first;
++	struct sk_buff *frag_last;
+ };
+ 
+ struct port {
+@@ -500,37 +505,35 @@ static void cns3xxx_alloc_rx_buf(struct 
+ 	struct _rx_ring *rx_ring = sw->rx_ring;
+ 	unsigned int i = rx_ring->alloc_index;
+ 	struct rx_desc *desc = &(rx_ring)->desc[i];
+-	struct sk_buff *skb;
++	void *buf;
+ 	unsigned int phys;
+ 
+ 	for (received += rx_ring->alloc_count; received > 0; received--) {
+-		if ((skb = dev_alloc_skb(MAX_MRU))) {
+-			if (SKB_DMA_REALIGN)
+-				skb_reserve(skb, SKB_DMA_REALIGN);
+-			skb_reserve(skb, NET_IP_ALIGN);
+-			phys = dma_map_single(NULL, skb->data,
+-				    CNS3XXX_MAX_MTU, DMA_FROM_DEVICE);
+-			if (dma_mapping_error(NULL, phys)) {
+-				dev_kfree_skb(skb);
+-				/* Failed to map, better luck next time */
+-				goto out;;
+-			}
+-			desc->sdp = phys;
+-		} else {
+-			/* Failed to allocate skb, try again next time */
++		buf = kzalloc(RX_SEGMENT_ALLOC_SIZE, GFP_ATOMIC);
++		if (!buf)
++			goto out;
++
++		phys = dma_map_single(NULL, buf + SKB_HEAD_ALIGN,
++				      RX_SEGMENT_MRU, DMA_FROM_DEVICE);
++		if (dma_mapping_error(NULL, phys)) {
++			kfree(buf);
+ 			goto out;
+ 		}
+ 
++		desc->sdl = RX_SEGMENT_MRU;
++		desc->sdp = phys;
++
+ 		/* put the new buffer on RX-free queue */
+-		rx_ring->buff_tab[i] = skb;
++		rx_ring->buff_tab[i] = buf;
+ 		rx_ring->phys_tab[i] = phys;
+ 		if (i == RX_DESCS - 1) {
+ 			i = 0;
+ 			desc->config0 = END_OF_RING | FIRST_SEGMENT |
+-					LAST_SEGMENT | CNS3XXX_MAX_MTU;
++					LAST_SEGMENT | RX_SEGMENT_MRU;
+ 			desc = &(rx_ring)->desc[i];
+ 		} else {
+-			desc->config0 = FIRST_SEGMENT | LAST_SEGMENT | CNS3XXX_MAX_MTU;
++			desc->config0 = FIRST_SEGMENT | LAST_SEGMENT |
++					RX_SEGMENT_MRU;
+ 			i++;
+ 			desc++;
+ 		}
+@@ -588,49 +591,78 @@ static int eth_poll(struct napi_struct *
+ 
+ 	while (desc->cown) {
+ 		struct sk_buff *skb;
++		int reserve = SKB_HEAD_ALIGN;
+ 
+ 		if (received >= budget)
+ 			break;
+ 
+-		skb = rx_ring->buff_tab[i];
++		/* process received frame */
++		dma_unmap_single(&dev->dev, rx_ring->phys_tab[i],
++				 RX_SEGMENT_MRU, DMA_FROM_DEVICE);
++
++		skb = build_skb(rx_ring->buff_tab[i]);
++		if (!skb)
++			break;
+ 
+ 		dev = switch_port_tab[desc->sp]->netdev;
+ 
+ 		length = desc->sdl;
+-		/* process received frame */
+-		dma_unmap_single(&dev->dev, rx_ring->phys_tab[i],
+-				 length, DMA_FROM_DEVICE);
++		if (desc->fsd && !desc->lsd)
++			length = RX_SEGMENT_MRU;
+ 
++		if (!desc->fsd) {
++			reserve -= NET_IP_ALIGN;
++			if (!desc->lsd)
++				length += NET_IP_ALIGN;
++		}
++
++		skb_reserve(skb, reserve);
+ 		skb_put(skb, length);
+ 
+-		skb->dev = dev;
+-		skb->protocol = eth_type_trans(skb, dev);
++		if (!sw->frag_first)
++			sw->frag_first = skb;
++		else {
++			if (sw->frag_first == sw->frag_last)
++				skb_frag_add_head(sw->frag_first, skb);
++			sw->frag_last->next = skb;
++			sw->frag_first->len += skb->len;
++			sw->frag_first->data_len += skb->len;
++			sw->frag_first->truesize += skb->truesize;
++		}
++		sw->frag_last = skb;
+ 
+-		dev->stats.rx_packets++;
+-		dev->stats.rx_bytes += length;
++		if (desc->lsd) {
++			skb = sw->frag_first;
++			skb->protocol = eth_type_trans(skb, dev);
++
++			dev->stats.rx_packets++;
++			dev->stats.rx_bytes += skb->len;
++
++			/* RX Hardware checksum offload */
++			skb->ip_summed = CHECKSUM_NONE;
++			switch (desc->prot) {
++				case 1:
++				case 2:
++				case 5:
++				case 6:
++				case 13:
++				case 14:
++					if (desc->l4f)
++						break;
+ 
+-		/* RX Hardware checksum offload */
+-		switch (desc->prot) {
+-			case 1:
+-			case 2:
+-			case 5:
+-			case 6:
+-			case 13:
+-			case 14:
+-				if (desc->l4f)
+-					skb->ip_summed = CHECKSUM_NONE;
+-				else
+ 					skb->ip_summed = CHECKSUM_UNNECESSARY;
+-			break;
+-			default:
+-				skb->ip_summed = CHECKSUM_NONE;
+-			break;
+-		}
++					break;
++				default:
++				break;
++			}
+ 
+-		napi_gro_receive(napi, skb);
++			napi_gro_receive(napi, skb);
+ 
+-		received++;
++			sw->frag_first = NULL;
++			sw->frag_last = NULL;
++		}
+ 
++		received++;
+ 		if (++i == RX_DESCS) {
+ 			i = 0;
+ 			desc = &(rx_ring)->desc[i];
+@@ -671,12 +703,6 @@ static int eth_xmit(struct sk_buff *skb,
+ 	if (pmap == 8)
+ 		pmap = (1 << 4);
+ 
+-	if (skb->len > CNS3XXX_MAX_MTU) {
+-		dev_kfree_skb(skb);
+-		dev->stats.tx_errors++;
+-		return NETDEV_TX_OK;
+-	}
+-
+ 	spin_lock(&tx_lock);
+ 
+ 	if ((tx_ring->num_used + nr_frags) >= TX_DESCS) {
+@@ -701,8 +727,7 @@ static int eth_xmit(struct sk_buff *skb,
+ 
+ 		len = skb->len;
+ 
+-		phys = dma_map_single(NULL, skb->data, len,
+-				      	DMA_TO_DEVICE);
++		phys = dma_map_single(NULL, skb->data, len, DMA_TO_DEVICE);
+ 
+ 		tx_desc->sdp = phys;
+ 		tx_desc->pmap = pmap;
+@@ -849,24 +874,24 @@ static int init_rings(struct sw *sw)
+ 	/* Setup RX buffers */
+ 	for (i = 0; i < RX_DESCS; i++) {
+ 		struct rx_desc *desc = &(rx_ring)->desc[i];
+-		struct sk_buff *skb;
+-		if (!(skb = dev_alloc_skb(MAX_MRU)))
++		void *buf;
++
++		buf = kzalloc(RX_SEGMENT_ALLOC_SIZE, GFP_KERNEL);
++		if (!buf)
+ 			return -ENOMEM;
+-		if (SKB_DMA_REALIGN)
+-			skb_reserve(skb, SKB_DMA_REALIGN);
+-		skb_reserve(skb, NET_IP_ALIGN);
+-		desc->sdl = CNS3XXX_MAX_MTU;
++
++		desc->sdl = RX_SEGMENT_MRU;
+ 		if (i == (RX_DESCS - 1))
+ 			desc->eor = 1;
+ 		desc->fsd = 1;
+ 		desc->lsd = 1;
+ 
+-		desc->sdp = dma_map_single(NULL, skb->data,
+-					    CNS3XXX_MAX_MTU, DMA_FROM_DEVICE);
+-		if (dma_mapping_error(NULL, desc->sdp)) {
++		desc->sdp = dma_map_single(NULL, buf + SKB_HEAD_ALIGN,
++					   RX_SEGMENT_MRU, DMA_FROM_DEVICE);
++		if (dma_mapping_error(NULL, desc->sdp))
+ 			return -EIO;
+-		}
+-		rx_ring->buff_tab[i] = skb;
++
++		rx_ring->buff_tab[i] = buf;
+ 		rx_ring->phys_tab[i] = desc->sdp;
+ 		desc->cown = 0;
+ 	}
+@@ -905,12 +930,13 @@ static void destroy_rings(struct sw *sw)
+ 			struct _rx_ring *rx_ring = sw->rx_ring;
+ 			struct rx_desc *desc = &(rx_ring)->desc[i];
+ 			struct sk_buff *skb = sw->rx_ring->buff_tab[i];
+-			if (skb) {
+-				dma_unmap_single(NULL,
+-						 desc->sdp,
+-						 CNS3XXX_MAX_MTU, DMA_FROM_DEVICE);
+-				dev_kfree_skb(skb);
+-			}
++
++			if (!skb)
++				continue;
++
++			dma_unmap_single(NULL, desc->sdp, RX_SEGMENT_MRU,
++					 DMA_FROM_DEVICE);
++			dev_kfree_skb(skb);
+ 		}
+ 		dma_pool_free(rx_dma_pool, sw->rx_ring->desc, sw->rx_ring->phys_addr);
+ 		dma_pool_destroy(rx_dma_pool);
+@@ -1085,13 +1111,22 @@ static int eth_set_mac(struct net_device
+ 	return 0;
+ }
+ 
++static int cns3xxx_change_mtu(struct net_device *dev, int new_mtu)
++{
++	if (new_mtu > MAX_MTU)
++		return -EINVAL;
++
++	dev->mtu = new_mtu;
++	return 0;
++}
++
+ static const struct net_device_ops cns3xxx_netdev_ops = {
+ 	.ndo_open = eth_open,
+ 	.ndo_stop = eth_close,
+ 	.ndo_start_xmit = eth_xmit,
+ 	.ndo_set_rx_mode = eth_rx_mode,
+ 	.ndo_do_ioctl = eth_ioctl,
+-	.ndo_change_mtu = eth_change_mtu,
++	.ndo_change_mtu = cns3xxx_change_mtu,
+ 	.ndo_set_mac_address = eth_set_mac,
+ 	.ndo_validate_addr = eth_validate_addr,
+ };
+@@ -1124,6 +1159,10 @@ static int __devinit eth_init_one(struct
+ 		goto err_free;
+ 	}
+ 
++	temp = __raw_readl(&sw->regs->phy_auto_addr);
++	temp |= (3 << 30); /* maximum frame length: 9600 bytes */
++	__raw_writel(temp, &sw->regs->phy_auto_addr);
++
+ 	for (i = 0; i < 4; i++) {
+ 		temp = __raw_readl(&sw->regs->mac_cfg[i]);
+ 		temp |= (PORT_DISABLE);