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-rw-r--r--drivers/net/ethernet/natsemi/sonic.c150
-rw-r--r--drivers/net/ethernet/natsemi/sonic.h18
2 files changed, 105 insertions, 63 deletions
diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c
index 9d2bddc4951b..26848acec63d 100644
--- a/drivers/net/ethernet/natsemi/sonic.c
+++ b/drivers/net/ethernet/natsemi/sonic.c
@@ -428,6 +428,59 @@ static int index_from_addr(struct sonic_local *lp, dma_addr_t addr,
return -ENOENT;
}
+/* Allocate and map a new skb to be used as a receive buffer. */
+static bool sonic_alloc_rb(struct net_device *dev, struct sonic_local *lp,
+ struct sk_buff **new_skb, dma_addr_t *new_addr)
+{
+ *new_skb = netdev_alloc_skb(dev, SONIC_RBSIZE + 2);
+ if (!*new_skb)
+ return false;
+
+ if (SONIC_BUS_SCALE(lp->dma_bitmode) == 2)
+ skb_reserve(*new_skb, 2);
+
+ *new_addr = dma_map_single(lp->device, skb_put(*new_skb, SONIC_RBSIZE),
+ SONIC_RBSIZE, DMA_FROM_DEVICE);
+ if (!*new_addr) {
+ dev_kfree_skb(*new_skb);
+ *new_skb = NULL;
+ return false;
+ }
+
+ return true;
+}
+
+/* Place a new receive resource in the Receive Resource Area and update RWP. */
+static void sonic_update_rra(struct net_device *dev, struct sonic_local *lp,
+ dma_addr_t old_addr, dma_addr_t new_addr)
+{
+ unsigned int entry = sonic_rr_entry(dev, SONIC_READ(SONIC_RWP));
+ unsigned int end = sonic_rr_entry(dev, SONIC_READ(SONIC_RRP));
+ u32 buf;
+
+ /* The resources in the range [RRP, RWP) belong to the SONIC. This loop
+ * scans the other resources in the RRA, those in the range [RWP, RRP).
+ */
+ do {
+ buf = (sonic_rra_get(dev, entry, SONIC_RR_BUFADR_H) << 16) |
+ sonic_rra_get(dev, entry, SONIC_RR_BUFADR_L);
+
+ if (buf == old_addr)
+ break;
+
+ entry = (entry + 1) & SONIC_RRS_MASK;
+ } while (entry != end);
+
+ WARN_ONCE(buf != old_addr, "failed to find resource!\n");
+
+ sonic_rra_put(dev, entry, SONIC_RR_BUFADR_H, new_addr >> 16);
+ sonic_rra_put(dev, entry, SONIC_RR_BUFADR_L, new_addr & 0xffff);
+
+ entry = (entry + 1) & SONIC_RRS_MASK;
+
+ SONIC_WRITE(SONIC_RWP, sonic_rr_addr(dev, entry));
+}
+
/*
* We have a good packet(s), pass it/them up the network stack.
*/
@@ -436,18 +489,15 @@ static void sonic_rx(struct net_device *dev)
struct sonic_local *lp = netdev_priv(dev);
int entry = lp->cur_rx;
int prev_entry = lp->eol_rx;
+ bool rbe = false;
while (sonic_rda_get(dev, entry, SONIC_RD_IN_USE) == 0) {
- struct sk_buff *used_skb;
- struct sk_buff *new_skb;
- dma_addr_t new_laddr;
- u16 bufadr_l;
- u16 bufadr_h;
- int pkt_len;
u16 status = sonic_rda_get(dev, entry, SONIC_RD_STATUS);
/* If the RD has LPKT set, the chip has finished with the RB */
if ((status & SONIC_RCR_PRX) && (status & SONIC_RCR_LPKT)) {
+ struct sk_buff *new_skb;
+ dma_addr_t new_laddr;
u32 addr = (sonic_rda_get(dev, entry,
SONIC_RD_PKTPTR_H) << 16) |
sonic_rda_get(dev, entry, SONIC_RD_PKTPTR_L);
@@ -458,55 +508,35 @@ static void sonic_rx(struct net_device *dev)
break;
}
- /* Malloc up new buffer. */
- new_skb = netdev_alloc_skb(dev, SONIC_RBSIZE + 2);
- if (new_skb == NULL) {
+ if (sonic_alloc_rb(dev, lp, &new_skb, &new_laddr)) {
+ struct sk_buff *used_skb = lp->rx_skb[i];
+ int pkt_len;
+
+ /* Pass the used buffer up the stack */
+ dma_unmap_single(lp->device, addr, SONIC_RBSIZE,
+ DMA_FROM_DEVICE);
+
+ pkt_len = sonic_rda_get(dev, entry,
+ SONIC_RD_PKTLEN);
+ skb_trim(used_skb, pkt_len);
+ used_skb->protocol = eth_type_trans(used_skb,
+ dev);
+ netif_rx(used_skb);
+ lp->stats.rx_packets++;
+ lp->stats.rx_bytes += pkt_len;
+
+ lp->rx_skb[i] = new_skb;
+ lp->rx_laddr[i] = new_laddr;
+ } else {
+ /* Failed to obtain a new buffer so re-use it */
+ new_laddr = addr;
lp->stats.rx_dropped++;
- break;
}
- /* provide 16 byte IP header alignment unless DMA requires otherwise */
- if(SONIC_BUS_SCALE(lp->dma_bitmode) == 2)
- skb_reserve(new_skb, 2);
-
- new_laddr = dma_map_single(lp->device, skb_put(new_skb, SONIC_RBSIZE),
- SONIC_RBSIZE, DMA_FROM_DEVICE);
- if (!new_laddr) {
- dev_kfree_skb(new_skb);
- printk(KERN_ERR "%s: Failed to map rx buffer, dropping packet.\n", dev->name);
- lp->stats.rx_dropped++;
- break;
- }
-
- /* now we have a new skb to replace it, pass the used one up the stack */
- dma_unmap_single(lp->device, lp->rx_laddr[entry], SONIC_RBSIZE, DMA_FROM_DEVICE);
- used_skb = lp->rx_skb[i];
- pkt_len = sonic_rda_get(dev, entry, SONIC_RD_PKTLEN);
- skb_trim(used_skb, pkt_len);
- used_skb->protocol = eth_type_trans(used_skb, dev);
- netif_rx(used_skb);
- lp->stats.rx_packets++;
- lp->stats.rx_bytes += pkt_len;
-
- /* and insert the new skb */
- lp->rx_laddr[i] = new_laddr;
- lp->rx_skb[i] = new_skb;
-
- bufadr_l = (unsigned long)new_laddr & 0xffff;
- bufadr_h = (unsigned long)new_laddr >> 16;
- sonic_rra_put(dev, i, SONIC_RR_BUFADR_L, bufadr_l);
- sonic_rra_put(dev, i, SONIC_RR_BUFADR_H, bufadr_h);
- /*
- * this was the last packet out of the current receive buffer
- * give the buffer back to the SONIC
+ /* If RBE is already asserted when RWP advances then
+ * it's safe to clear RBE after processing this packet.
*/
- lp->cur_rwp += SIZEOF_SONIC_RR * SONIC_BUS_SCALE(lp->dma_bitmode);
- if (lp->cur_rwp >= lp->rra_end) lp->cur_rwp = lp->rra_laddr & 0xffff;
- SONIC_WRITE(SONIC_RWP, lp->cur_rwp);
- if (SONIC_READ(SONIC_ISR) & SONIC_INT_RBE) {
- netif_dbg(lp, rx_err, dev, "%s: rx buffer exhausted\n",
- __func__);
- SONIC_WRITE(SONIC_ISR, SONIC_INT_RBE); /* clear the flag */
- }
+ rbe = rbe || SONIC_READ(SONIC_ISR) & SONIC_INT_RBE;
+ sonic_update_rra(dev, lp, addr, new_laddr);
}
/*
* give back the descriptor
@@ -528,6 +558,9 @@ static void sonic_rx(struct net_device *dev)
sonic_rda_get(dev, lp->eol_rx, SONIC_RD_LINK));
lp->eol_rx = prev_entry;
}
+
+ if (rbe)
+ SONIC_WRITE(SONIC_ISR, SONIC_INT_RBE);
/*
* If any worth-while packets have been received, netif_rx()
* has done a mark_bh(NET_BH) for us and will work on them
@@ -642,15 +675,10 @@ static int sonic_init(struct net_device *dev)
}
/* initialize all RRA registers */
- lp->rra_end = (lp->rra_laddr + SONIC_NUM_RRS * SIZEOF_SONIC_RR *
- SONIC_BUS_SCALE(lp->dma_bitmode)) & 0xffff;
- lp->cur_rwp = (lp->rra_laddr + (SONIC_NUM_RRS - 1) * SIZEOF_SONIC_RR *
- SONIC_BUS_SCALE(lp->dma_bitmode)) & 0xffff;
-
- SONIC_WRITE(SONIC_RSA, lp->rra_laddr & 0xffff);
- SONIC_WRITE(SONIC_REA, lp->rra_end);
- SONIC_WRITE(SONIC_RRP, lp->rra_laddr & 0xffff);
- SONIC_WRITE(SONIC_RWP, lp->cur_rwp);
+ SONIC_WRITE(SONIC_RSA, sonic_rr_addr(dev, 0));
+ SONIC_WRITE(SONIC_REA, sonic_rr_addr(dev, SONIC_NUM_RRS));
+ SONIC_WRITE(SONIC_RRP, sonic_rr_addr(dev, 0));
+ SONIC_WRITE(SONIC_RWP, sonic_rr_addr(dev, SONIC_NUM_RRS - 1));
SONIC_WRITE(SONIC_URRA, lp->rra_laddr >> 16);
SONIC_WRITE(SONIC_EOBC, (SONIC_RBSIZE >> 1) - (lp->dma_bitmode ? 2 : 1));
diff --git a/drivers/net/ethernet/natsemi/sonic.h b/drivers/net/ethernet/natsemi/sonic.h
index e6d47e45c5c2..cc2f7b4b77e3 100644
--- a/drivers/net/ethernet/natsemi/sonic.h
+++ b/drivers/net/ethernet/natsemi/sonic.h
@@ -314,8 +314,6 @@ struct sonic_local {
u32 rda_laddr; /* logical DMA address of RDA */
dma_addr_t rx_laddr[SONIC_NUM_RRS]; /* logical DMA addresses of rx skbuffs */
dma_addr_t tx_laddr[SONIC_NUM_TDS]; /* logical DMA addresses of tx skbuffs */
- unsigned int rra_end;
- unsigned int cur_rwp;
unsigned int cur_rx;
unsigned int cur_tx; /* first unacked transmit packet */
unsigned int eol_rx;
@@ -450,6 +448,22 @@ static inline __u16 sonic_rra_get(struct net_device* dev, int entry,
(entry * SIZEOF_SONIC_RR) + offset);
}
+static inline u16 sonic_rr_addr(struct net_device *dev, int entry)
+{
+ struct sonic_local *lp = netdev_priv(dev);
+
+ return lp->rra_laddr +
+ entry * SIZEOF_SONIC_RR * SONIC_BUS_SCALE(lp->dma_bitmode);
+}
+
+static inline u16 sonic_rr_entry(struct net_device *dev, u16 addr)
+{
+ struct sonic_local *lp = netdev_priv(dev);
+
+ return (addr - (u16)lp->rra_laddr) / (SIZEOF_SONIC_RR *
+ SONIC_BUS_SCALE(lp->dma_bitmode));
+}
+
static const char version[] =
"sonic.c:v0.92 20.9.98 tsbogend@alpha.franken.de\n";
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.