Commit d9e651bc authored by Dhananjay Phadke's avatar Dhananjay Phadke Committed by Jeff Garzik

netxen: cut-through rx changes

NX3031 supports cut-through operation where ingress packets are
directly dma'ed into host buffers to reduce latency.

This requires larger dma buffers (2kb) and different alignemnt.

The buffer posting logic is changed a bit. The free rx buffers
are maintained in linked list, since the received reference
handles can be out of order. However rx descriptors are still
posted sequentially, indexed by producer.
Signed-off-by: default avatarDhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent c9fc891f
...@@ -140,6 +140,7 @@ ...@@ -140,6 +140,7 @@
#define NX_RX_NORMAL_BUF_MAX_LEN (NX_MAX_ETHERHDR + NX_ETHERMTU) #define NX_RX_NORMAL_BUF_MAX_LEN (NX_MAX_ETHERHDR + NX_ETHERMTU)
#define NX_P2_RX_JUMBO_BUF_MAX_LEN (NX_MAX_ETHERHDR + P2_MAX_MTU) #define NX_P2_RX_JUMBO_BUF_MAX_LEN (NX_MAX_ETHERHDR + P2_MAX_MTU)
#define NX_P3_RX_JUMBO_BUF_MAX_LEN (NX_MAX_ETHERHDR + P3_MAX_MTU) #define NX_P3_RX_JUMBO_BUF_MAX_LEN (NX_MAX_ETHERHDR + P3_MAX_MTU)
#define NX_CT_DEFAULT_RX_BUF_LEN 2048
#define MAX_RX_BUFFER_LENGTH 1760 #define MAX_RX_BUFFER_LENGTH 1760
#define MAX_RX_JUMBO_BUFFER_LENGTH 8062 #define MAX_RX_JUMBO_BUFFER_LENGTH 8062
...@@ -391,8 +392,8 @@ struct rcv_desc { ...@@ -391,8 +392,8 @@ struct rcv_desc {
}; };
/* opcode field in status_desc */ /* opcode field in status_desc */
#define RCV_NIC_PKT (0xA) #define NETXEN_NIC_RXPKT_DESC 0x04
#define STATUS_NIC_PKT ((RCV_NIC_PKT) << 12) #define NETXEN_OLD_RXPKT_DESC 0x3f
/* for status field in status_desc */ /* for status field in status_desc */
#define STATUS_NEED_CKSUM (1) #define STATUS_NEED_CKSUM (1)
...@@ -424,6 +425,8 @@ struct rcv_desc { ...@@ -424,6 +425,8 @@ struct rcv_desc {
(((sts_data) >> 28) & 0xFFFF) (((sts_data) >> 28) & 0xFFFF)
#define netxen_get_sts_prot(sts_data) \ #define netxen_get_sts_prot(sts_data) \
(((sts_data) >> 44) & 0x0F) (((sts_data) >> 44) & 0x0F)
#define netxen_get_sts_pkt_offset(sts_data) \
(((sts_data) >> 48) & 0x1F)
#define netxen_get_sts_opcode(sts_data) \ #define netxen_get_sts_opcode(sts_data) \
(((sts_data) >> 58) & 0x03F) (((sts_data) >> 58) & 0x03F)
...@@ -438,17 +441,30 @@ struct rcv_desc { ...@@ -438,17 +441,30 @@ struct rcv_desc {
struct status_desc { struct status_desc {
/* Bit pattern: 0-3 port, 4-7 status, 8-11 type, 12-27 total_length /* Bit pattern: 0-3 port, 4-7 status, 8-11 type, 12-27 total_length
28-43 reference_handle, 44-47 protocol, 48-52 unused 28-43 reference_handle, 44-47 protocol, 48-52 pkt_offset
53-55 desc_cnt, 56-57 owner, 58-63 opcode 53-55 desc_cnt, 56-57 owner, 58-63 opcode
*/ */
__le64 status_desc_data; __le64 status_desc_data;
__le32 hash_value; union {
u8 hash_type; struct {
u8 msg_type; __le32 hash_value;
u8 unused; u8 hash_type;
/* Bit pattern: 0-6 lro_count indicates frag sequence, u8 msg_type;
7 last_frag indicates last frag */ u8 unused;
u8 lro; union {
/* Bit pattern: 0-6 lro_count indicates frag
* sequence, 7 last_frag indicates last frag
*/
u8 lro;
/* chained buffers */
u8 nr_frags;
};
};
struct {
__le16 frag_handles[4];
};
};
} __attribute__ ((aligned(16))); } __attribute__ ((aligned(16)));
enum { enum {
...@@ -774,6 +790,7 @@ struct netxen_cmd_buffer { ...@@ -774,6 +790,7 @@ struct netxen_cmd_buffer {
/* In rx_buffer, we do not need multiple fragments as is a single buffer */ /* In rx_buffer, we do not need multiple fragments as is a single buffer */
struct netxen_rx_buffer { struct netxen_rx_buffer {
struct list_head list;
struct sk_buff *skb; struct sk_buff *skb;
u64 dma; u64 dma;
u16 ref_handle; u16 ref_handle;
...@@ -854,6 +871,7 @@ struct nx_host_rds_ring { ...@@ -854,6 +871,7 @@ struct nx_host_rds_ring {
u32 dma_size; u32 dma_size;
u32 skb_size; u32 skb_size;
struct netxen_rx_buffer *rx_buf_arr; /* rx buffers for receive */ struct netxen_rx_buffer *rx_buf_arr; /* rx buffers for receive */
struct list_head free_list;
int begin_alloc; int begin_alloc;
}; };
......
This diff is collapsed.
...@@ -262,17 +262,30 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter) ...@@ -262,17 +262,30 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter)
rds_ring->max_rx_desc_count = rds_ring->max_rx_desc_count =
adapter->max_rx_desc_count; adapter->max_rx_desc_count;
rds_ring->flags = RCV_DESC_NORMAL; rds_ring->flags = RCV_DESC_NORMAL;
rds_ring->dma_size = RX_DMA_MAP_LEN; if (adapter->ahw.cut_through) {
rds_ring->skb_size = MAX_RX_BUFFER_LENGTH; rds_ring->dma_size =
NX_CT_DEFAULT_RX_BUF_LEN;
rds_ring->skb_size =
NX_CT_DEFAULT_RX_BUF_LEN;
} else {
rds_ring->dma_size = RX_DMA_MAP_LEN;
rds_ring->skb_size =
MAX_RX_BUFFER_LENGTH;
}
break; break;
case RCV_DESC_JUMBO: case RCV_DESC_JUMBO:
rds_ring->max_rx_desc_count = rds_ring->max_rx_desc_count =
adapter->max_jumbo_rx_desc_count; adapter->max_jumbo_rx_desc_count;
rds_ring->flags = RCV_DESC_JUMBO; rds_ring->flags = RCV_DESC_JUMBO;
rds_ring->dma_size = RX_JUMBO_DMA_MAP_LEN; if (NX_IS_REVISION_P3(adapter->ahw.revision_id))
rds_ring->dma_size =
NX_P3_RX_JUMBO_BUF_MAX_LEN;
else
rds_ring->dma_size =
NX_P2_RX_JUMBO_BUF_MAX_LEN;
rds_ring->skb_size = rds_ring->skb_size =
MAX_RX_JUMBO_BUFFER_LENGTH; rds_ring->dma_size + NET_IP_ALIGN;
break; break;
case RCV_RING_LRO: case RCV_RING_LRO:
...@@ -294,6 +307,7 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter) ...@@ -294,6 +307,7 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter)
goto err_out; goto err_out;
} }
memset(rds_ring->rx_buf_arr, 0, RCV_BUFFSIZE); memset(rds_ring->rx_buf_arr, 0, RCV_BUFFSIZE);
INIT_LIST_HEAD(&rds_ring->free_list);
rds_ring->begin_alloc = 0; rds_ring->begin_alloc = 0;
/* /*
* Now go through all of them, set reference handles * Now go through all of them, set reference handles
...@@ -302,6 +316,8 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter) ...@@ -302,6 +316,8 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter)
num_rx_bufs = rds_ring->max_rx_desc_count; num_rx_bufs = rds_ring->max_rx_desc_count;
rx_buf = rds_ring->rx_buf_arr; rx_buf = rds_ring->rx_buf_arr;
for (i = 0; i < num_rx_bufs; i++) { for (i = 0; i < num_rx_bufs; i++) {
list_add_tail(&rx_buf->list,
&rds_ring->free_list);
rx_buf->ref_handle = i; rx_buf->ref_handle = i;
rx_buf->state = NETXEN_BUFFER_FREE; rx_buf->state = NETXEN_BUFFER_FREE;
rx_buf++; rx_buf++;
...@@ -1137,15 +1153,47 @@ int netxen_receive_peg_ready(struct netxen_adapter *adapter) ...@@ -1137,15 +1153,47 @@ int netxen_receive_peg_ready(struct netxen_adapter *adapter)
return 0; return 0;
} }
static struct sk_buff *netxen_process_rxbuf(struct netxen_adapter *adapter,
struct nx_host_rds_ring *rds_ring, u16 index, u16 cksum)
{
struct netxen_rx_buffer *buffer;
struct sk_buff *skb;
buffer = &rds_ring->rx_buf_arr[index];
pci_unmap_single(adapter->pdev, buffer->dma, rds_ring->dma_size,
PCI_DMA_FROMDEVICE);
skb = buffer->skb;
if (!skb)
goto no_skb;
if (likely(adapter->rx_csum && cksum == STATUS_CKSUM_OK)) {
adapter->stats.csummed++;
skb->ip_summed = CHECKSUM_UNNECESSARY;
} else
skb->ip_summed = CHECKSUM_NONE;
skb->dev = adapter->netdev;
buffer->skb = NULL;
no_skb:
buffer->state = NETXEN_BUFFER_FREE;
buffer->lro_current_frags = 0;
buffer->lro_expected_frags = 0;
list_add_tail(&buffer->list, &rds_ring->free_list);
return skb;
}
/* /*
* netxen_process_rcv() send the received packet to the protocol stack. * netxen_process_rcv() send the received packet to the protocol stack.
* and if the number of receives exceeds RX_BUFFERS_REFILL, then we * and if the number of receives exceeds RX_BUFFERS_REFILL, then we
* invoke the routine to send more rx buffers to the Phantom... * invoke the routine to send more rx buffers to the Phantom...
*/ */
static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid, static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid,
struct status_desc *desc) struct status_desc *desc, struct status_desc *frag_desc)
{ {
struct pci_dev *pdev = adapter->pdev;
struct net_device *netdev = adapter->netdev; struct net_device *netdev = adapter->netdev;
u64 sts_data = le64_to_cpu(desc->status_desc_data); u64 sts_data = le64_to_cpu(desc->status_desc_data);
int index = netxen_get_sts_refhandle(sts_data); int index = netxen_get_sts_refhandle(sts_data);
...@@ -1154,8 +1202,8 @@ static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid, ...@@ -1154,8 +1202,8 @@ static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid,
struct sk_buff *skb; struct sk_buff *skb;
u32 length = netxen_get_sts_totallength(sts_data); u32 length = netxen_get_sts_totallength(sts_data);
u32 desc_ctx; u32 desc_ctx;
u16 pkt_offset = 0, cksum;
struct nx_host_rds_ring *rds_ring; struct nx_host_rds_ring *rds_ring;
int ret;
desc_ctx = netxen_get_sts_type(sts_data); desc_ctx = netxen_get_sts_type(sts_data);
if (unlikely(desc_ctx >= NUM_RCV_DESC_RINGS)) { if (unlikely(desc_ctx >= NUM_RCV_DESC_RINGS)) {
...@@ -1191,41 +1239,52 @@ static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid, ...@@ -1191,41 +1239,52 @@ static void netxen_process_rcv(struct netxen_adapter *adapter, int ctxid,
} }
} }
pci_unmap_single(pdev, buffer->dma, rds_ring->dma_size, cksum = netxen_get_sts_status(sts_data);
PCI_DMA_FROMDEVICE);
skb = (struct sk_buff *)buffer->skb;
if (likely(adapter->rx_csum && skb = netxen_process_rxbuf(adapter, rds_ring, index, cksum);
netxen_get_sts_status(sts_data) == STATUS_CKSUM_OK)) { if (!skb)
adapter->stats.csummed++; return;
skb->ip_summed = CHECKSUM_UNNECESSARY;
} else
skb->ip_summed = CHECKSUM_NONE;
skb->dev = netdev;
if (desc_ctx == RCV_DESC_LRO_CTXID) { if (desc_ctx == RCV_DESC_LRO_CTXID) {
/* True length was only available on the last pkt */ /* True length was only available on the last pkt */
skb_put(skb, buffer->lro_length); skb_put(skb, buffer->lro_length);
} else { } else {
skb_put(skb, length); if (length > rds_ring->skb_size)
skb_put(skb, rds_ring->skb_size);
else
skb_put(skb, length);
pkt_offset = netxen_get_sts_pkt_offset(sts_data);
if (pkt_offset)
skb_pull(skb, pkt_offset);
} }
skb->protocol = eth_type_trans(skb, netdev); skb->protocol = eth_type_trans(skb, netdev);
ret = netif_receive_skb(skb);
netdev->last_rx = jiffies;
/* /*
* We just consumed one buffer so post a buffer. * rx buffer chaining is disabled, walk and free
* any spurious rx buffer chain.
*/ */
buffer->skb = NULL; if (frag_desc) {
buffer->state = NETXEN_BUFFER_FREE; u16 i, nr_frags = desc->nr_frags;
buffer->lro_current_frags = 0;
buffer->lro_expected_frags = 0; dev_kfree_skb_any(skb);
for (i = 0; i < nr_frags; i++) {
index = frag_desc->frag_handles[i];
skb = netxen_process_rxbuf(adapter,
rds_ring, index, cksum);
if (skb)
dev_kfree_skb_any(skb);
}
adapter->stats.rxdropped++;
} else {
adapter->stats.no_rcv++; netif_receive_skb(skb);
adapter->stats.rxbytes += length; netdev->last_rx = jiffies;
adapter->stats.no_rcv++;
adapter->stats.rxbytes += length;
}
} }
/* Process Receive status ring */ /* Process Receive status ring */
...@@ -1233,9 +1292,11 @@ u32 netxen_process_rcv_ring(struct netxen_adapter *adapter, int ctxid, int max) ...@@ -1233,9 +1292,11 @@ u32 netxen_process_rcv_ring(struct netxen_adapter *adapter, int ctxid, int max)
{ {
struct netxen_recv_context *recv_ctx = &(adapter->recv_ctx[ctxid]); struct netxen_recv_context *recv_ctx = &(adapter->recv_ctx[ctxid]);
struct status_desc *desc_head = recv_ctx->rcv_status_desc_head; struct status_desc *desc_head = recv_ctx->rcv_status_desc_head;
struct status_desc *desc; /* used to read status desc here */ struct status_desc *desc, *frag_desc;
u32 consumer = recv_ctx->status_rx_consumer; u32 consumer = recv_ctx->status_rx_consumer;
int count = 0, ring; int count = 0, ring;
u64 sts_data;
u16 opcode;
while (count < max) { while (count < max) {
desc = &desc_head[consumer]; desc = &desc_head[consumer];
...@@ -1244,9 +1305,26 @@ u32 netxen_process_rcv_ring(struct netxen_adapter *adapter, int ctxid, int max) ...@@ -1244,9 +1305,26 @@ u32 netxen_process_rcv_ring(struct netxen_adapter *adapter, int ctxid, int max)
netxen_get_sts_owner(desc)); netxen_get_sts_owner(desc));
break; break;
} }
netxen_process_rcv(adapter, ctxid, desc);
sts_data = le64_to_cpu(desc->status_desc_data);
opcode = netxen_get_sts_opcode(sts_data);
frag_desc = NULL;
if (opcode == NETXEN_NIC_RXPKT_DESC) {
if (desc->nr_frags) {
consumer = get_next_index(consumer,
adapter->max_rx_desc_count);
frag_desc = &desc_head[consumer];
netxen_set_sts_owner(frag_desc,
STATUS_OWNER_PHANTOM);
}
}
netxen_process_rcv(adapter, ctxid, desc, frag_desc);
netxen_set_sts_owner(desc, STATUS_OWNER_PHANTOM); netxen_set_sts_owner(desc, STATUS_OWNER_PHANTOM);
consumer = (consumer + 1) & (adapter->max_rx_desc_count - 1);
consumer = get_next_index(consumer,
adapter->max_rx_desc_count);
count++; count++;
} }
for (ring = 0; ring < adapter->max_rds_rings; ring++) for (ring = 0; ring < adapter->max_rds_rings; ring++)
...@@ -1348,36 +1426,31 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid) ...@@ -1348,36 +1426,31 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid)
int index = 0; int index = 0;
netxen_ctx_msg msg = 0; netxen_ctx_msg msg = 0;
dma_addr_t dma; dma_addr_t dma;
struct list_head *head;
rds_ring = &recv_ctx->rds_rings[ringid]; rds_ring = &recv_ctx->rds_rings[ringid];
producer = rds_ring->producer; producer = rds_ring->producer;
index = rds_ring->begin_alloc; index = rds_ring->begin_alloc;
buffer = &rds_ring->rx_buf_arr[index]; head = &rds_ring->free_list;
/* We can start writing rx descriptors into the phantom memory. */ /* We can start writing rx descriptors into the phantom memory. */
while (buffer->state == NETXEN_BUFFER_FREE) { while (!list_empty(head)) {
skb = dev_alloc_skb(rds_ring->skb_size); skb = dev_alloc_skb(rds_ring->skb_size);
if (unlikely(!skb)) { if (unlikely(!skb)) {
/*
* TODO
* We need to schedule the posting of buffers to the pegs.
*/
rds_ring->begin_alloc = index; rds_ring->begin_alloc = index;
DPRINTK(ERR, "netxen_post_rx_buffers: "
" allocated only %d buffers\n", count);
break; break;
} }
buffer = list_entry(head->next, struct netxen_rx_buffer, list);
list_del(&buffer->list);
count++; /* now there should be no failure */ count++; /* now there should be no failure */
pdesc = &rds_ring->desc_head[producer]; pdesc = &rds_ring->desc_head[producer];
#if defined(XGB_DEBUG) if (!adapter->ahw.cut_through)
*(unsigned long *)(skb->head) = 0xc0debabe; skb_reserve(skb, 2);
if (skb_is_nonlinear(skb)) {
printk("Allocated SKB @%p is nonlinear\n");
}
#endif
skb_reserve(skb, 2);
/* This will be setup when we receive the /* This will be setup when we receive the
* buffer after it has been filled FSL TBD TBD * buffer after it has been filled FSL TBD TBD
* skb->dev = netdev; * skb->dev = netdev;
...@@ -1395,7 +1468,6 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid) ...@@ -1395,7 +1468,6 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid)
producer = producer =
get_next_index(producer, rds_ring->max_rx_desc_count); get_next_index(producer, rds_ring->max_rx_desc_count);
index = get_next_index(index, rds_ring->max_rx_desc_count); index = get_next_index(index, rds_ring->max_rx_desc_count);
buffer = &rds_ring->rx_buf_arr[index];
} }
/* if we did allocate buffers, then write the count to Phantom */ /* if we did allocate buffers, then write the count to Phantom */
if (count) { if (count) {
...@@ -1439,32 +1511,29 @@ static void netxen_post_rx_buffers_nodb(struct netxen_adapter *adapter, ...@@ -1439,32 +1511,29 @@ static void netxen_post_rx_buffers_nodb(struct netxen_adapter *adapter,
struct netxen_rx_buffer *buffer; struct netxen_rx_buffer *buffer;
int count = 0; int count = 0;
int index = 0; int index = 0;
struct list_head *head;
rds_ring = &recv_ctx->rds_rings[ringid]; rds_ring = &recv_ctx->rds_rings[ringid];
producer = rds_ring->producer; producer = rds_ring->producer;
index = rds_ring->begin_alloc; index = rds_ring->begin_alloc;
buffer = &rds_ring->rx_buf_arr[index]; head = &rds_ring->free_list;
/* We can start writing rx descriptors into the phantom memory. */ /* We can start writing rx descriptors into the phantom memory. */
while (buffer->state == NETXEN_BUFFER_FREE) { while (!list_empty(head)) {
skb = dev_alloc_skb(rds_ring->skb_size); skb = dev_alloc_skb(rds_ring->skb_size);
if (unlikely(!skb)) { if (unlikely(!skb)) {
/*
* We need to schedule the posting of buffers to the pegs.
*/
rds_ring->begin_alloc = index; rds_ring->begin_alloc = index;
DPRINTK(ERR, "netxen_post_rx_buffers_nodb: "
" allocated only %d buffers\n", count);
break; break;
} }
buffer = list_entry(head->next, struct netxen_rx_buffer, list);
list_del(&buffer->list);
count++; /* now there should be no failure */ count++; /* now there should be no failure */
pdesc = &rds_ring->desc_head[producer]; pdesc = &rds_ring->desc_head[producer];
skb_reserve(skb, 2); if (!adapter->ahw.cut_through)
/* skb_reserve(skb, 2);
* This will be setup when we receive the
* buffer after it has been filled
* skb->dev = netdev;
*/
buffer->skb = skb; buffer->skb = skb;
buffer->state = NETXEN_BUFFER_BUSY; buffer->state = NETXEN_BUFFER_BUSY;
buffer->dma = pci_map_single(pdev, skb->data, buffer->dma = pci_map_single(pdev, skb->data,
......
...@@ -844,17 +844,18 @@ netxen_nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent) ...@@ -844,17 +844,18 @@ netxen_nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
/* Handshake with the card before we register the devices. */ /* Handshake with the card before we register the devices. */
netxen_phantom_init(adapter, NETXEN_NIC_PEG_TUNE); netxen_phantom_init(adapter, NETXEN_NIC_PEG_TUNE);
if (NX_IS_REVISION_P3(revision_id)) {
adapter->hw_read_wx(adapter,
NETXEN_MIU_MN_CONTROL, &val, 4);
adapter->ahw.cut_through = (val & 0x4) ? 1 : 0;
dev_info(&pdev->dev, "firmware running in %s mode\n",
adapter->ahw.cut_through ? "cut through" : "legacy");
}
} /* first_driver */ } /* first_driver */
netxen_nic_flash_print(adapter); netxen_nic_flash_print(adapter);
if (NX_IS_REVISION_P3(revision_id)) {
adapter->hw_read_wx(adapter,
NETXEN_MIU_MN_CONTROL, &val, 4);
adapter->ahw.cut_through = (val & 0x4) ? 1 : 0;
dev_info(&pdev->dev, "firmware running in %s mode\n",
adapter->ahw.cut_through ? "cut through" : "legacy");
}
/* /*
* See if the firmware gave us a virtual-physical port mapping. * See if the firmware gave us a virtual-physical port mapping.
*/ */
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment