I have updated the dmfe.c network driver for 2.4.0-test by adding proper
locking (I hope), and also made transmission much efficient.
I would appreciate any feedback from people using this driver, to confirm
that I did not break it.
It would also be great if someone could take a look at the lock handling,
to confirm that is is correct and sufficient.
/Tobias
--- dmfe.c.orig Wed Nov 15 19:53:48 2000
+++ dmfe.c Wed Nov 15 21:35:24 2000
@@ -57,6 +57,11 @@
Resource usage cleanups.
Report driver version to user.
+ Tobias Ringström <zajbot@goteborg.utfors.se> :
+ Added proper locking.
+ Rewrote the transmit code to actually use the ring buffer,
+ and to generate a lot fewer interrupts.
+
TODO
Implement pci_driver::suspend() and pci_driver::resume()
@@ -108,6 +113,7 @@
#define TX_MAX_SEND_CNT 0x1 /* Maximum tx packet per time */
#define TX_DESC_CNT 0x10 /* Allocated Tx descriptors */
#define RX_DESC_CNT 0x10 /* Allocated Rx descriptors */
+#define TX_IRQ_THR 12
#define DESC_ALL_CNT TX_DESC_CNT+RX_DESC_CNT
#define TX_BUF_ALLOC 0x600
#define RX_ALLOC_SIZE 0x620
@@ -188,6 +194,8 @@
u32 cr7_data;
u32 cr15_data;
+ spinlock_t lock;
+
/* descriptor pointer */
unsigned char *buf_pool_ptr; /* Tx buffer pool memory */
unsigned char *buf_pool_start; /* Tx buffer pool align dword */
@@ -198,8 +206,7 @@
struct rx_desc *first_rx_desc;
struct rx_desc *rx_insert_ptr;
struct rx_desc *rx_ready_ptr; /* packet come pointer */
- u32 tx_packet_cnt; /* transmitted packet count */
- u32 tx_queue_cnt; /* wait to send packet count */
+ u32 tx_live_cnt; /* number of used/live tx slots */
u32 rx_avail_cnt; /* available rx descriptor count */
u32 interval_rx_cnt; /* rx packet count a callback time */
@@ -490,8 +497,6 @@
/* system variable init */
db->cr6_data = CR6_DEFAULT | dmfe_cr6_user_set;
- db->tx_packet_cnt = 0;
- db->tx_queue_cnt = 0;
db->rx_avail_cnt = 0;
db->link_failed = 0;
db->wait_reset = 0;
@@ -595,46 +600,42 @@
{
struct dmfe_board_info *db = dev->priv;
struct tx_desc *txptr;
+ static unsigned pkt_num = TX_IRQ_THR;
DMFE_DBUG(0, "dmfe_start_xmit", 0);
-
- netif_stop_queue(dev);
-
- /* Too large packet check */
- if (skb->len > MAX_PACKET_SIZE) {
- printk(KERN_ERR "%s: oversized frame (%d bytes) for transmit.\n", dev->name, (u16) skb->len);
- dev_kfree_skb(skb);
- return 0;
- }
- /* No Tx resource check, it never happen nromally */
- if (db->tx_packet_cnt >= TX_FREE_DESC_CNT) {
- return 1;
- }
+
+ spin_lock_irq(&db->lock);
/* transmit this packet */
txptr = db->tx_insert_ptr;
memcpy((char *) txptr->tx_buf_ptr, (char *) skb->data, skb->len);
- txptr->tdes1 = 0xe1000000 | skb->len;
+ if (--pkt_num == 0)
+ {
+ txptr->tdes1 = 0xe1000000 | skb->len;
+ pkt_num = TX_IRQ_THR;
+ }
+ else
+ txptr->tdes1 = 0x61000000 | skb->len;
+
+ /* Transmit Packet Process */
+ txptr->tdes0 = 0x80000000; /* set owner bit to DM910X */
+ outl(0x1, dev->base_addr + DCR1); /* Issue Tx polling comand */
+ dev->trans_start = jiffies; /* saved the time stamp */
/* Point to next transmit free descriptor */
- db->tx_insert_ptr = (struct tx_desc *) txptr->next_tx_desc;
+ txptr = (struct tx_desc *)txptr->next_tx_desc;
- /* Transmit Packet Process */
- if (db->tx_packet_cnt < TX_MAX_SEND_CNT) {
- txptr->tdes0 = 0x80000000; /* set owner bit to DM910X */
- db->tx_packet_cnt++; /* Ready to send count */
- outl(0x1, dev->base_addr + DCR1); /* Issue Tx polling comand */
- } else {
- db->tx_queue_cnt++; /* queue the tx packet */
- outl(0x1, dev->base_addr + DCR1); /* Issue Tx polling comand */
- }
+ if (txptr->tdes0 & 0x80000000)
+ netif_stop_queue(dev);
- /* Tx resource check */
- if (db->tx_packet_cnt < TX_FREE_DESC_CNT)
- netif_wake_queue(dev);
+ db->tx_insert_ptr = txptr;
+ db->tx_live_cnt++;
+
+ spin_unlock_irq(&tp->lock);
/* free this SKB */
dev_kfree_skb(skb);
+
return 0;
}
@@ -713,12 +714,14 @@
outl(0, ioaddr + DCR7); /* disable all interrupt */
return;
}
+
+ spin_lock(&db->lock);
+
/* Free the transmitted descriptor */
txptr = db->tx_remove_ptr;
- while (db->tx_packet_cnt) {
+ while (db->tx_live_cnt > 0 && (txptr->tdes0 & 0x80000000) == 0)
+ {
/* printk("tdes0=%x\n", txptr->tdes0); */
- if (txptr->tdes0 & 0x80000000)
- break;
db->stats.tx_packets++;
if ((txptr->tdes0 & TDES0_ERR_MASK) && (txptr->tdes0 != 0x7fffffff)) {
@@ -734,23 +737,16 @@
db->stats.tx_errors++;
}
txptr = (struct tx_desc *) txptr->next_tx_desc;
- db->tx_packet_cnt--;
+ db->tx_live_cnt--;
}
/* Update TX remove pointer to next */
db->tx_remove_ptr = (struct tx_desc *) txptr;
- /* Send the Tx packet in queue */
- if ((db->tx_packet_cnt < TX_MAX_SEND_CNT) && db->tx_queue_cnt) {
- txptr->tdes0 = 0x80000000; /* set owner bit to DM910X */
- db->tx_packet_cnt++; /* Ready to send count */
- outl(0x1, ioaddr + DCR1); /* Issue Tx polling command */
- dev->trans_start = jiffies; /* saved the time stamp */
- db->tx_queue_cnt--;
- }
- /* Resource available check */
- if (db->tx_packet_cnt < TX_FREE_DESC_CNT)
+ if ((db->tx_insert_ptr->tdes0 & 0x80000000) == 0)
netif_wake_queue(dev);
+ spin_unlock(&db->lock);
+
/* Received the coming packet */
if (db->rx_avail_cnt)
dmfe_rx_packet(dev, db);
@@ -930,12 +926,14 @@
db->interval_rx_cnt = 0;
- if (db->wait_reset | (db->tx_packet_cnt &&
- ((jiffies - dev->trans_start) > DMFE_TX_TIMEOUT)) | (db->rx_error_cnt > 3)) {
+ if (db->wait_reset ||
+ (db->tx_live_cnt > 0 &&
+ ((jiffies - dev->trans_start) > DMFE_TX_TIMEOUT)) ||
+ (db->rx_error_cnt > 3)) {
/*
printk("wait_reset %x, tx cnt %x, rx err %x, time %x\n", db->wait_reset, db->tx_packet_cnt, db->rx_error_cnt, jiffies-dev->trans_start);
*/
- DMFE_DBUG(0, "Warn!! Warn!! Tx/Rx moniotr step1", db->tx_packet_cnt);
+ DMFE_DBUG(0, "Warn!! Warn!! Tx/Rx monitor step1", 0);
dmfe_dynamic_reset(dev);
db->timer.expires = DMFE_TIMER_WUT;
add_timer(&db->timer);
@@ -1022,8 +1020,7 @@
dmfe_free_rxbuffer(db);
/* system variable init */
- db->tx_packet_cnt = 0;
- db->tx_queue_cnt = 0;
+ db->tx_live_cnt = 0;
db->rx_avail_cnt = 0;
db->link_failed = 0;
db->wait_reset = 0;
@@ -1182,22 +1179,32 @@
}
/* Send a setup frame for DM9102/DM9102A
- This setup frame initilize DM910X addres filter mode
+ This setup frame initilize DM910X address filter mode
*/
static void send_filter_frame(struct net_device *dev, int mc_cnt)
{
struct dmfe_board_info *db = dev->priv;
struct dev_mc_list *mcptr;
struct tx_desc *txptr;
+ unsigned long flags;
u16 *addrptr;
u32 *suptr;
int i;
DMFE_DBUG(0, "send_filetr_frame()", 0);
+ spin_lock_irqsave(&db->lock, flags);
+
txptr = db->tx_insert_ptr;
suptr = (u32 *) txptr->tx_buf_ptr;
+ if (txptr->tdes0 & 0x80000000) {
+ spin_unlock_irq(&tp->lock);
+ printk(KERN_WARNING "%s: Too busy to send filter frame\n",
+ dev->name);
+ return;
+ }
+
/* Node address */
addrptr = (u16 *) dev->dev_addr;
*suptr++ = addrptr[0];
@@ -1224,19 +1231,15 @@
}
/* prepare the setup frame */
db->tx_insert_ptr = (struct tx_desc *) txptr->next_tx_desc;
+ db->tx_live_cnt++;
txptr->tdes1 = 0x890000c0;
- /* Resource Check and Send the setup packet */
- if (!db->tx_packet_cnt) {
- /* Resource Empty */
- db->tx_packet_cnt++;
- txptr->tdes0 = 0x80000000;
- update_cr6(db->cr6_data | 0x2000, dev->base_addr);
- outl(0x1, dev->base_addr + DCR1); /* Issue Tx polling command */
- update_cr6(db->cr6_data, dev->base_addr);
- } else {
- /* Put into TX queue */
- db->tx_queue_cnt++;
- }
+ /* Send the setup packet */
+ txptr->tdes0 = 0x80000000;
+ update_cr6(db->cr6_data | 0x2000, dev->base_addr);
+ outl(0x1, dev->base_addr + DCR1); /* Issue Tx polling command */
+ update_cr6(db->cr6_data, dev->base_addr);
+
+ spin_unlock_irqrestore(&tp->lock, flags);
}
/*
-
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This archive was generated by hypermail 2b29 : Wed Nov 15 2000 - 21:00:28 EST