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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/net/meth.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/net/meth.c')
-rw-r--r--drivers/net/meth.c843
1 files changed, 843 insertions, 0 deletions
diff --git a/drivers/net/meth.c b/drivers/net/meth.c
new file mode 100644
index 000000000000..e23655f5049f
--- /dev/null
+++ b/drivers/net/meth.c
@@ -0,0 +1,843 @@
+/*
+ * meth.c -- O2 Builtin 10/100 Ethernet driver
+ *
+ * Copyright (C) 2001-2003 Ilya Volynets
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/sched.h>
+#include <linux/kernel.h> /* printk() */
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/errno.h> /* error codes */
+#include <linux/types.h> /* size_t */
+#include <linux/interrupt.h> /* mark_bh */
+
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/device.h> /* struct device, et al */
+#include <linux/netdevice.h> /* struct device, and other headers */
+#include <linux/etherdevice.h> /* eth_type_trans */
+#include <linux/ip.h> /* struct iphdr */
+#include <linux/tcp.h> /* struct tcphdr */
+#include <linux/skbuff.h>
+#include <linux/mii.h> /* MII definitions */
+
+#include <asm/ip32/mace.h>
+#include <asm/ip32/ip32_ints.h>
+
+#include <asm/io.h>
+#include <asm/checksum.h>
+#include <asm/scatterlist.h>
+#include <linux/dma-mapping.h>
+
+#include "meth.h"
+
+#ifndef MFE_DEBUG
+#define MFE_DEBUG 0
+#endif
+
+#if MFE_DEBUG>=1
+#define DPRINTK(str,args...) printk(KERN_DEBUG "meth: %s: " str, __FUNCTION__ , ## args)
+#define MFE_RX_DEBUG 2
+#else
+#define DPRINTK(str,args...)
+#define MFE_RX_DEBUG 0
+#endif
+
+
+static const char *meth_str="SGI O2 Fast Ethernet";
+MODULE_AUTHOR("Ilya Volynets <ilya@theIlya.com>");
+MODULE_DESCRIPTION("SGI O2 Builtin Fast Ethernet driver");
+
+#define HAVE_TX_TIMEOUT
+/* The maximum time waited (in jiffies) before assuming a Tx failed. (400ms) */
+#define TX_TIMEOUT (400*HZ/1000)
+
+#ifdef HAVE_TX_TIMEOUT
+static int timeout = TX_TIMEOUT;
+MODULE_PARM(timeout, "i");
+#endif
+
+/*
+ * This structure is private to each device. It is used to pass
+ * packets in and out, so there is place for a packet
+ */
+struct meth_private {
+ struct net_device_stats stats;
+ /* in-memory copy of MAC Control register */
+ unsigned long mac_ctrl;
+ /* in-memory copy of DMA Control register */
+ unsigned long dma_ctrl;
+ /* address of PHY, used by mdio_* functions, initialized in mdio_probe */
+ unsigned long phy_addr;
+ tx_packet *tx_ring;
+ dma_addr_t tx_ring_dma;
+ struct sk_buff *tx_skbs[TX_RING_ENTRIES];
+ dma_addr_t tx_skb_dmas[TX_RING_ENTRIES];
+ unsigned long tx_read, tx_write, tx_count;
+
+ rx_packet *rx_ring[RX_RING_ENTRIES];
+ dma_addr_t rx_ring_dmas[RX_RING_ENTRIES];
+ struct sk_buff *rx_skbs[RX_RING_ENTRIES];
+ unsigned long rx_write;
+
+ spinlock_t meth_lock;
+};
+
+static void meth_tx_timeout(struct net_device *dev);
+static irqreturn_t meth_interrupt(int irq, void *dev_id, struct pt_regs *pregs);
+
+/* global, initialized in ip32-setup.c */
+char o2meth_eaddr[8]={0,0,0,0,0,0,0,0};
+
+static inline void load_eaddr(struct net_device *dev)
+{
+ int i;
+ DPRINTK("Loading MAC Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
+ (int)o2meth_eaddr[0]&0xFF,(int)o2meth_eaddr[1]&0xFF,(int)o2meth_eaddr[2]&0xFF,
+ (int)o2meth_eaddr[3]&0xFF,(int)o2meth_eaddr[4]&0xFF,(int)o2meth_eaddr[5]&0xFF);
+ for (i = 0; i < 6; i++)
+ dev->dev_addr[i] = o2meth_eaddr[i];
+ mace->eth.mac_addr = (*(unsigned long*)o2meth_eaddr) >> 16;
+}
+
+/*
+ * Waits for BUSY status of mdio bus to clear
+ */
+#define WAIT_FOR_PHY(___rval) \
+ while ((___rval = mace->eth.phy_data) & MDIO_BUSY) { \
+ udelay(25); \
+ }
+/*read phy register, return value read */
+static unsigned long mdio_read(struct meth_private *priv, unsigned long phyreg)
+{
+ unsigned long rval;
+ WAIT_FOR_PHY(rval);
+ mace->eth.phy_regs = (priv->phy_addr << 5) | (phyreg & 0x1f);
+ udelay(25);
+ mace->eth.phy_trans_go = 1;
+ udelay(25);
+ WAIT_FOR_PHY(rval);
+ return rval & MDIO_DATA_MASK;
+}
+
+static int mdio_probe(struct meth_private *priv)
+{
+ int i;
+ unsigned long p2, p3;
+ /* check if phy is detected already */
+ if(priv->phy_addr>=0&&priv->phy_addr<32)
+ return 0;
+ spin_lock(&priv->meth_lock);
+ for (i=0;i<32;++i){
+ priv->phy_addr=i;
+ p2=mdio_read(priv,2);
+ p3=mdio_read(priv,3);
+#if MFE_DEBUG>=2
+ switch ((p2<<12)|(p3>>4)){
+ case PHY_QS6612X:
+ DPRINTK("PHY is QS6612X\n");
+ break;
+ case PHY_ICS1889:
+ DPRINTK("PHY is ICS1889\n");
+ break;
+ case PHY_ICS1890:
+ DPRINTK("PHY is ICS1890\n");
+ break;
+ case PHY_DP83840:
+ DPRINTK("PHY is DP83840\n");
+ break;
+ }
+#endif
+ if(p2!=0xffff&&p2!=0x0000){
+ DPRINTK("PHY code: %x\n",(p2<<12)|(p3>>4));
+ break;
+ }
+ }
+ spin_unlock(&priv->meth_lock);
+ if(priv->phy_addr<32) {
+ return 0;
+ }
+ DPRINTK("Oopsie! PHY is not known!\n");
+ priv->phy_addr=-1;
+ return -ENODEV;
+}
+
+static void meth_check_link(struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ unsigned long mii_advertising = mdio_read(priv, 4);
+ unsigned long mii_partner = mdio_read(priv, 5);
+ unsigned long negotiated = mii_advertising & mii_partner;
+ unsigned long duplex, speed;
+
+ if (mii_partner == 0xffff)
+ return;
+
+ speed = (negotiated & 0x0380) ? METH_100MBIT : 0;
+ duplex = ((negotiated & 0x0100) || (negotiated & 0x01C0) == 0x0040) ?
+ METH_PHY_FDX : 0;
+
+ if ((priv->mac_ctrl & METH_PHY_FDX) ^ duplex) {
+ DPRINTK("Setting %s-duplex\n", duplex ? "full" : "half");
+ if (duplex)
+ priv->mac_ctrl |= METH_PHY_FDX;
+ else
+ priv->mac_ctrl &= ~METH_PHY_FDX;
+ mace->eth.mac_ctrl = priv->mac_ctrl;
+ }
+
+ if ((priv->mac_ctrl & METH_100MBIT) ^ speed) {
+ DPRINTK("Setting %dMbs mode\n", speed ? 100 : 10);
+ if (duplex)
+ priv->mac_ctrl |= METH_100MBIT;
+ else
+ priv->mac_ctrl &= ~METH_100MBIT;
+ mace->eth.mac_ctrl = priv->mac_ctrl;
+ }
+}
+
+
+static int meth_init_tx_ring(struct meth_private *priv)
+{
+ /* Init TX ring */
+ priv->tx_ring = dma_alloc_coherent(NULL, TX_RING_BUFFER_SIZE,
+ &priv->tx_ring_dma, GFP_ATOMIC);
+ if (!priv->tx_ring)
+ return -ENOMEM;
+ memset(priv->tx_ring, 0, TX_RING_BUFFER_SIZE);
+ priv->tx_count = priv->tx_read = priv->tx_write = 0;
+ mace->eth.tx_ring_base = priv->tx_ring_dma;
+ /* Now init skb save area */
+ memset(priv->tx_skbs, 0, sizeof(priv->tx_skbs));
+ memset(priv->tx_skb_dmas, 0, sizeof(priv->tx_skb_dmas));
+ return 0;
+}
+
+static int meth_init_rx_ring(struct meth_private *priv)
+{
+ int i;
+
+ for (i = 0; i < RX_RING_ENTRIES; i++) {
+ priv->rx_skbs[i] = alloc_skb(METH_RX_BUFF_SIZE, 0);
+ /* 8byte status vector + 3quad padding + 2byte padding,
+ * to put data on 64bit aligned boundary */
+ skb_reserve(priv->rx_skbs[i],METH_RX_HEAD);
+ priv->rx_ring[i]=(rx_packet*)(priv->rx_skbs[i]->head);
+ /* I'll need to re-sync it after each RX */
+ priv->rx_ring_dmas[i] =
+ dma_map_single(NULL, priv->rx_ring[i],
+ METH_RX_BUFF_SIZE, DMA_FROM_DEVICE);
+ mace->eth.rx_fifo = priv->rx_ring_dmas[i];
+ }
+ priv->rx_write = 0;
+ return 0;
+}
+static void meth_free_tx_ring(struct meth_private *priv)
+{
+ int i;
+
+ /* Remove any pending skb */
+ for (i = 0; i < TX_RING_ENTRIES; i++) {
+ if (priv->tx_skbs[i])
+ dev_kfree_skb(priv->tx_skbs[i]);
+ priv->tx_skbs[i] = NULL;
+ }
+ dma_free_coherent(NULL, TX_RING_BUFFER_SIZE, priv->tx_ring,
+ priv->tx_ring_dma);
+}
+
+/* Presumes RX DMA engine is stopped, and RX fifo ring is reset */
+static void meth_free_rx_ring(struct meth_private *priv)
+{
+ int i;
+
+ for (i = 0; i < RX_RING_ENTRIES; i++) {
+ dma_unmap_single(NULL, priv->rx_ring_dmas[i],
+ METH_RX_BUFF_SIZE, DMA_FROM_DEVICE);
+ priv->rx_ring[i] = 0;
+ priv->rx_ring_dmas[i] = 0;
+ kfree_skb(priv->rx_skbs[i]);
+ }
+}
+
+int meth_reset(struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+
+ /* Reset card */
+ mace->eth.mac_ctrl = SGI_MAC_RESET;
+ udelay(1);
+ mace->eth.mac_ctrl = 0;
+ udelay(25);
+
+ /* Load ethernet address */
+ load_eaddr(dev);
+ /* Should load some "errata", but later */
+
+ /* Check for device */
+ if (mdio_probe(priv) < 0) {
+ DPRINTK("Unable to find PHY\n");
+ return -ENODEV;
+ }
+
+ /* Initial mode: 10 | Half-duplex | Accept normal packets */
+ priv->mac_ctrl = METH_ACCEPT_MCAST | METH_DEFAULT_IPG;
+ if (dev->flags | IFF_PROMISC)
+ priv->mac_ctrl |= METH_PROMISC;
+ mace->eth.mac_ctrl = priv->mac_ctrl;
+
+ /* Autonegotiate speed and duplex mode */
+ meth_check_link(dev);
+
+ /* Now set dma control, but don't enable DMA, yet */
+ priv->dma_ctrl = (4 << METH_RX_OFFSET_SHIFT) |
+ (RX_RING_ENTRIES << METH_RX_DEPTH_SHIFT);
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ return 0;
+}
+
+/*============End Helper Routines=====================*/
+
+/*
+ * Open and close
+ */
+static int meth_open(struct net_device *dev)
+{
+ struct meth_private *priv = dev->priv;
+ int ret;
+
+ priv->phy_addr = -1; /* No PHY is known yet... */
+
+ /* Initialize the hardware */
+ ret = meth_reset(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Allocate the ring buffers */
+ ret = meth_init_tx_ring(priv);
+ if (ret < 0)
+ return ret;
+ ret = meth_init_rx_ring(priv);
+ if (ret < 0)
+ goto out_free_tx_ring;
+
+ ret = request_irq(dev->irq, meth_interrupt, 0, meth_str, dev);
+ if (ret) {
+ printk(KERN_ERR "%s: Can't get irq %d\n", dev->name, dev->irq);
+ goto out_free_rx_ring;
+ }
+
+ /* Start DMA */
+ priv->dma_ctrl |= METH_DMA_TX_EN | /*METH_DMA_TX_INT_EN |*/
+ METH_DMA_RX_EN | METH_DMA_RX_INT_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ DPRINTK("About to start queue\n");
+ netif_start_queue(dev);
+
+ return 0;
+
+out_free_rx_ring:
+ meth_free_rx_ring(priv);
+out_free_tx_ring:
+ meth_free_tx_ring(priv);
+
+ return ret;
+}
+
+static int meth_release(struct net_device *dev)
+{
+ struct meth_private *priv = dev->priv;
+
+ DPRINTK("Stopping queue\n");
+ netif_stop_queue(dev); /* can't transmit any more */
+ /* shut down DMA */
+ priv->dma_ctrl &= ~(METH_DMA_TX_EN | METH_DMA_TX_INT_EN |
+ METH_DMA_RX_EN | METH_DMA_RX_INT_EN);
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+ free_irq(dev->irq, dev);
+ meth_free_tx_ring(priv);
+ meth_free_rx_ring(priv);
+
+ return 0;
+}
+
+/*
+ * Receive a packet: retrieve, encapsulate and pass over to upper levels
+ */
+static void meth_rx(struct net_device* dev, unsigned long int_status)
+{
+ struct sk_buff *skb;
+ unsigned long status;
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ unsigned long fifo_rptr = (int_status & METH_INT_RX_RPTR_MASK) >> 8;
+
+ spin_lock(&priv->meth_lock);
+ priv->dma_ctrl &= ~METH_DMA_RX_INT_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+ spin_unlock(&priv->meth_lock);
+
+ if (int_status & METH_INT_RX_UNDERFLOW) {
+ fifo_rptr = (fifo_rptr - 1) & 0x0f;
+ }
+ while (priv->rx_write != fifo_rptr) {
+ dma_unmap_single(NULL, priv->rx_ring_dmas[priv->rx_write],
+ METH_RX_BUFF_SIZE, DMA_FROM_DEVICE);
+ status = priv->rx_ring[priv->rx_write]->status.raw;
+#if MFE_DEBUG
+ if (!(status & METH_RX_ST_VALID)) {
+ DPRINTK("Not received? status=%016lx\n",status);
+ }
+#endif
+ if ((!(status & METH_RX_STATUS_ERRORS)) && (status & METH_RX_ST_VALID)) {
+ int len = (status & 0xffff) - 4; /* omit CRC */
+ /* length sanity check */
+ if (len < 60 || len > 1518) {
+ printk(KERN_DEBUG "%s: bogus packet size: %ld, status=%#2lx.\n",
+ dev->name, priv->rx_write,
+ priv->rx_ring[priv->rx_write]->status.raw);
+ priv->stats.rx_errors++;
+ priv->stats.rx_length_errors++;
+ skb = priv->rx_skbs[priv->rx_write];
+ } else {
+ skb = alloc_skb(METH_RX_BUFF_SIZE, GFP_ATOMIC | GFP_DMA);
+ if (!skb) {
+ /* Ouch! No memory! Drop packet on the floor */
+ DPRINTK("No mem: dropping packet\n");
+ priv->stats.rx_dropped++;
+ skb = priv->rx_skbs[priv->rx_write];
+ } else {
+ struct sk_buff *skb_c = priv->rx_skbs[priv->rx_write];
+ /* 8byte status vector + 3quad padding + 2byte padding,
+ * to put data on 64bit aligned boundary */
+ skb_reserve(skb, METH_RX_HEAD);
+ /* Write metadata, and then pass to the receive level */
+ skb_put(skb_c, len);
+ priv->rx_skbs[priv->rx_write] = skb;
+ skb_c->dev = dev;
+ skb_c->protocol = eth_type_trans(skb_c, dev);
+ dev->last_rx = jiffies;
+ priv->stats.rx_packets++;
+ priv->stats.rx_bytes += len;
+ netif_rx(skb_c);
+ }
+ }
+ } else {
+ priv->stats.rx_errors++;
+ skb=priv->rx_skbs[priv->rx_write];
+#if MFE_DEBUG>0
+ printk(KERN_WARNING "meth: RX error: status=0x%016lx\n",status);
+ if(status&METH_RX_ST_RCV_CODE_VIOLATION)
+ printk(KERN_WARNING "Receive Code Violation\n");
+ if(status&METH_RX_ST_CRC_ERR)
+ printk(KERN_WARNING "CRC error\n");
+ if(status&METH_RX_ST_INV_PREAMBLE_CTX)
+ printk(KERN_WARNING "Invalid Preamble Context\n");
+ if(status&METH_RX_ST_LONG_EVT_SEEN)
+ printk(KERN_WARNING "Long Event Seen...\n");
+ if(status&METH_RX_ST_BAD_PACKET)
+ printk(KERN_WARNING "Bad Packet\n");
+ if(status&METH_RX_ST_CARRIER_EVT_SEEN)
+ printk(KERN_WARNING "Carrier Event Seen\n");
+#endif
+ }
+ priv->rx_ring[priv->rx_write] = (rx_packet*)skb->head;
+ priv->rx_ring[priv->rx_write]->status.raw = 0;
+ priv->rx_ring_dmas[priv->rx_write] =
+ dma_map_single(NULL, priv->rx_ring[priv->rx_write],
+ METH_RX_BUFF_SIZE, DMA_FROM_DEVICE);
+ mace->eth.rx_fifo = priv->rx_ring_dmas[priv->rx_write];
+ ADVANCE_RX_PTR(priv->rx_write);
+ }
+ spin_lock(&priv->meth_lock);
+ /* In case there was underflow, and Rx DMA was disabled */
+ priv->dma_ctrl |= METH_DMA_RX_INT_EN | METH_DMA_RX_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+ mace->eth.int_stat = METH_INT_RX_THRESHOLD;
+ spin_unlock(&priv->meth_lock);
+}
+
+static int meth_tx_full(struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+
+ return (priv->tx_count >= TX_RING_ENTRIES - 1);
+}
+
+static void meth_tx_cleanup(struct net_device* dev, unsigned long int_status)
+{
+ struct meth_private *priv = dev->priv;
+ unsigned long status;
+ struct sk_buff *skb;
+ unsigned long rptr = (int_status&TX_INFO_RPTR) >> 16;
+
+ spin_lock(&priv->meth_lock);
+
+ /* Stop DMA notification */
+ priv->dma_ctrl &= ~(METH_DMA_TX_INT_EN);
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ while (priv->tx_read != rptr) {
+ skb = priv->tx_skbs[priv->tx_read];
+ status = priv->tx_ring[priv->tx_read].header.raw;
+#if MFE_DEBUG>=1
+ if (priv->tx_read == priv->tx_write)
+ DPRINTK("Auchi! tx_read=%d,tx_write=%d,rptr=%d?\n", priv->tx_read, priv->tx_write,rptr);
+#endif
+ if (status & METH_TX_ST_DONE) {
+ if (status & METH_TX_ST_SUCCESS){
+ priv->stats.tx_packets++;
+ priv->stats.tx_bytes += skb->len;
+ } else {
+ priv->stats.tx_errors++;
+#if MFE_DEBUG>=1
+ DPRINTK("TX error: status=%016lx <",status);
+ if(status & METH_TX_ST_SUCCESS)
+ printk(" SUCCESS");
+ if(status & METH_TX_ST_TOOLONG)
+ printk(" TOOLONG");
+ if(status & METH_TX_ST_UNDERRUN)
+ printk(" UNDERRUN");
+ if(status & METH_TX_ST_EXCCOLL)
+ printk(" EXCCOLL");
+ if(status & METH_TX_ST_DEFER)
+ printk(" DEFER");
+ if(status & METH_TX_ST_LATECOLL)
+ printk(" LATECOLL");
+ printk(" >\n");
+#endif
+ }
+ } else {
+ DPRINTK("RPTR points us here, but packet not done?\n");
+ break;
+ }
+ dev_kfree_skb_irq(skb);
+ priv->tx_skbs[priv->tx_read] = NULL;
+ priv->tx_ring[priv->tx_read].header.raw = 0;
+ priv->tx_read = (priv->tx_read+1)&(TX_RING_ENTRIES-1);
+ priv->tx_count--;
+ }
+
+ /* wake up queue if it was stopped */
+ if (netif_queue_stopped(dev) && !meth_tx_full(dev)) {
+ netif_wake_queue(dev);
+ }
+
+ mace->eth.int_stat = METH_INT_TX_EMPTY | METH_INT_TX_PKT;
+ spin_unlock(&priv->meth_lock);
+}
+
+static void meth_error(struct net_device* dev, unsigned status)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+
+ printk(KERN_WARNING "meth: error status: 0x%08x\n",status);
+ /* check for errors too... */
+ if (status & (METH_INT_TX_LINK_FAIL))
+ printk(KERN_WARNING "meth: link failure\n");
+ /* Should I do full reset in this case? */
+ if (status & (METH_INT_MEM_ERROR))
+ printk(KERN_WARNING "meth: memory error\n");
+ if (status & (METH_INT_TX_ABORT))
+ printk(KERN_WARNING "meth: aborted\n");
+ if (status & (METH_INT_RX_OVERFLOW))
+ printk(KERN_WARNING "meth: Rx overflow\n");
+ if (status & (METH_INT_RX_UNDERFLOW)) {
+ printk(KERN_WARNING "meth: Rx underflow\n");
+ spin_lock(&priv->meth_lock);
+ mace->eth.int_stat = METH_INT_RX_UNDERFLOW;
+ /* more underflow interrupts will be delivered,
+ * effectively throwing us into an infinite loop.
+ * Thus I stop processing Rx in this case. */
+ priv->dma_ctrl &= ~METH_DMA_RX_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+ DPRINTK("Disabled meth Rx DMA temporarily\n");
+ spin_unlock(&priv->meth_lock);
+ }
+ mace->eth.int_stat = METH_INT_ERROR;
+}
+
+/*
+ * The typical interrupt entry point
+ */
+static irqreturn_t meth_interrupt(int irq, void *dev_id, struct pt_regs *pregs)
+{
+ struct net_device *dev = (struct net_device *)dev_id;
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ unsigned long status;
+
+ status = mace->eth.int_stat;
+ while (status & 0xff) {
+ /* First handle errors - if we get Rx underflow,
+ * Rx DMA will be disabled, and Rx handler will reenable
+ * it. I don't think it's possible to get Rx underflow,
+ * without getting Rx interrupt */
+ if (status & METH_INT_ERROR) {
+ meth_error(dev, status);
+ }
+ if (status & (METH_INT_TX_EMPTY | METH_INT_TX_PKT)) {
+ /* a transmission is over: free the skb */
+ meth_tx_cleanup(dev, status);
+ }
+ if (status & METH_INT_RX_THRESHOLD) {
+ if (!(priv->dma_ctrl & METH_DMA_RX_INT_EN))
+ break;
+ /* send it to meth_rx for handling */
+ meth_rx(dev, status);
+ }
+ status = mace->eth.int_stat;
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Transmits packets that fit into TX descriptor (are <=120B)
+ */
+static void meth_tx_short_prepare(struct meth_private *priv,
+ struct sk_buff *skb)
+{
+ tx_packet *desc = &priv->tx_ring[priv->tx_write];
+ int len = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
+
+ desc->header.raw = METH_TX_CMD_INT_EN | (len-1) | ((128-len) << 16);
+ /* maybe I should set whole thing to 0 first... */
+ memcpy(desc->data.dt + (120 - len), skb->data, skb->len);
+ if (skb->len < len)
+ memset(desc->data.dt + 120 - len + skb->len, 0, len-skb->len);
+}
+#define TX_CATBUF1 BIT(25)
+static void meth_tx_1page_prepare(struct meth_private *priv,
+ struct sk_buff *skb)
+{
+ tx_packet *desc = &priv->tx_ring[priv->tx_write];
+ void *buffer_data = (void *)(((unsigned long)skb->data + 7) & ~7);
+ int unaligned_len = (int)((unsigned long)buffer_data - (unsigned long)skb->data);
+ int buffer_len = skb->len - unaligned_len;
+ dma_addr_t catbuf;
+
+ desc->header.raw = METH_TX_CMD_INT_EN | TX_CATBUF1 | (skb->len - 1);
+
+ /* unaligned part */
+ if (unaligned_len) {
+ memcpy(desc->data.dt + (120 - unaligned_len),
+ skb->data, unaligned_len);
+ desc->header.raw |= (128 - unaligned_len) << 16;
+ }
+
+ /* first page */
+ catbuf = dma_map_single(NULL, buffer_data, buffer_len,
+ DMA_TO_DEVICE);
+ desc->data.cat_buf[0].form.start_addr = catbuf >> 3;
+ desc->data.cat_buf[0].form.len = buffer_len - 1;
+}
+#define TX_CATBUF2 BIT(26)
+static void meth_tx_2page_prepare(struct meth_private *priv,
+ struct sk_buff *skb)
+{
+ tx_packet *desc = &priv->tx_ring[priv->tx_write];
+ void *buffer1_data = (void *)(((unsigned long)skb->data + 7) & ~7);
+ void *buffer2_data = (void *)PAGE_ALIGN((unsigned long)skb->data);
+ int unaligned_len = (int)((unsigned long)buffer1_data - (unsigned long)skb->data);
+ int buffer1_len = (int)((unsigned long)buffer2_data - (unsigned long)buffer1_data);
+ int buffer2_len = skb->len - buffer1_len - unaligned_len;
+ dma_addr_t catbuf1, catbuf2;
+
+ desc->header.raw = METH_TX_CMD_INT_EN | TX_CATBUF1 | TX_CATBUF2| (skb->len - 1);
+ /* unaligned part */
+ if (unaligned_len){
+ memcpy(desc->data.dt + (120 - unaligned_len),
+ skb->data, unaligned_len);
+ desc->header.raw |= (128 - unaligned_len) << 16;
+ }
+
+ /* first page */
+ catbuf1 = dma_map_single(NULL, buffer1_data, buffer1_len,
+ DMA_TO_DEVICE);
+ desc->data.cat_buf[0].form.start_addr = catbuf1 >> 3;
+ desc->data.cat_buf[0].form.len = buffer1_len - 1;
+ /* second page */
+ catbuf2 = dma_map_single(NULL, buffer2_data, buffer2_len,
+ DMA_TO_DEVICE);
+ desc->data.cat_buf[1].form.start_addr = catbuf2 >> 3;
+ desc->data.cat_buf[1].form.len = buffer2_len - 1;
+}
+
+static void meth_add_to_tx_ring(struct meth_private *priv, struct sk_buff *skb)
+{
+ /* Remember the skb, so we can free it at interrupt time */
+ priv->tx_skbs[priv->tx_write] = skb;
+ if (skb->len <= 120) {
+ /* Whole packet fits into descriptor */
+ meth_tx_short_prepare(priv, skb);
+ } else if (PAGE_ALIGN((unsigned long)skb->data) !=
+ PAGE_ALIGN((unsigned long)skb->data + skb->len - 1)) {
+ /* Packet crosses page boundary */
+ meth_tx_2page_prepare(priv, skb);
+ } else {
+ /* Packet is in one page */
+ meth_tx_1page_prepare(priv, skb);
+ }
+ priv->tx_write = (priv->tx_write + 1) & (TX_RING_ENTRIES - 1);
+ mace->eth.tx_info = priv->tx_write;
+ priv->tx_count++;
+}
+
+/*
+ * Transmit a packet (called by the kernel)
+ */
+static int meth_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->meth_lock, flags);
+ /* Stop DMA notification */
+ priv->dma_ctrl &= ~(METH_DMA_TX_INT_EN);
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ meth_add_to_tx_ring(priv, skb);
+ dev->trans_start = jiffies; /* save the timestamp */
+
+ /* If TX ring is full, tell the upper layer to stop sending packets */
+ if (meth_tx_full(dev)) {
+ printk(KERN_DEBUG "TX full: stopping\n");
+ netif_stop_queue(dev);
+ }
+
+ /* Restart DMA notification */
+ priv->dma_ctrl |= METH_DMA_TX_INT_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ spin_unlock_irqrestore(&priv->meth_lock, flags);
+
+ return 0;
+}
+
+/*
+ * Deal with a transmit timeout.
+ */
+static void meth_tx_timeout(struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ unsigned long flags;
+
+ printk(KERN_WARNING "%s: transmit timed out\n", dev->name);
+
+ /* Protect against concurrent rx interrupts */
+ spin_lock_irqsave(&priv->meth_lock,flags);
+
+ /* Try to reset the interface. */
+ meth_reset(dev);
+
+ priv->stats.tx_errors++;
+
+ /* Clear all rings */
+ meth_free_tx_ring(priv);
+ meth_free_rx_ring(priv);
+ meth_init_tx_ring(priv);
+ meth_init_rx_ring(priv);
+
+ /* Restart dma */
+ priv->dma_ctrl |= METH_DMA_TX_EN | METH_DMA_RX_EN | METH_DMA_RX_INT_EN;
+ mace->eth.dma_ctrl = priv->dma_ctrl;
+
+ /* Enable interrupt */
+ spin_unlock_irqrestore(&priv->meth_lock, flags);
+
+ dev->trans_start = jiffies;
+ netif_wake_queue(dev);
+
+ return;
+}
+
+/*
+ * Ioctl commands
+ */
+static int meth_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ /* XXX Not yet implemented */
+ switch(cmd) {
+ case SIOCGMIIPHY:
+ case SIOCGMIIREG:
+ case SIOCSMIIREG:
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+/*
+ * Return statistics to the caller
+ */
+static struct net_device_stats *meth_stats(struct net_device *dev)
+{
+ struct meth_private *priv = (struct meth_private *) dev->priv;
+ return &priv->stats;
+}
+
+/*
+ * The init function.
+ */
+static struct net_device *meth_init(void)
+{
+ struct net_device *dev;
+ struct meth_private *priv;
+ int ret;
+
+ dev = alloc_etherdev(sizeof(struct meth_private));
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ dev->open = meth_open;
+ dev->stop = meth_release;
+ dev->hard_start_xmit = meth_tx;
+ dev->do_ioctl = meth_ioctl;
+ dev->get_stats = meth_stats;
+#ifdef HAVE_TX_TIMEOUT
+ dev->tx_timeout = meth_tx_timeout;
+ dev->watchdog_timeo = timeout;
+#endif
+ dev->irq = MACE_ETHERNET_IRQ;
+ dev->base_addr = (unsigned long)&mace->eth;
+
+ priv = (struct meth_private *) dev->priv;
+ spin_lock_init(&priv->meth_lock);
+
+ ret = register_netdev(dev);
+ if (ret) {
+ free_netdev(dev);
+ return ERR_PTR(ret);
+ }
+
+ printk(KERN_INFO "%s: SGI MACE Ethernet rev. %d\n",
+ dev->name, (unsigned int)(mace->eth.mac_ctrl >> 29));
+ return 0;
+}
+
+static struct net_device *meth_dev;
+
+static int __init meth_init_module(void)
+{
+ meth_dev = meth_init();
+ if (IS_ERR(meth_dev))
+ return PTR_ERR(meth_dev);
+ return 0;
+}
+
+static void __exit meth_exit_module(void)
+{
+ unregister_netdev(meth_dev);
+ free_netdev(meth_dev);
+}
+
+module_init(meth_init_module);
+module_exit(meth_exit_module);