summaryrefslogtreecommitdiff
path: root/drivers/net/macmace.c
diff options
context:
space:
mode:
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/macmace.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/macmace.c')
-rw-r--r--drivers/net/macmace.c710
1 files changed, 710 insertions, 0 deletions
diff --git a/drivers/net/macmace.c b/drivers/net/macmace.c
new file mode 100644
index 000000000000..79a6fc139757
--- /dev/null
+++ b/drivers/net/macmace.c
@@ -0,0 +1,710 @@
+/*
+ * Driver for the Macintosh 68K onboard MACE controller with PSC
+ * driven DMA. The MACE driver code is derived from mace.c. The
+ * Mac68k theory of operation is courtesy of the MacBSD wizards.
+ *
+ * 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.
+ *
+ * Copyright (C) 1996 Paul Mackerras.
+ * Copyright (C) 1998 Alan Cox <alan@redhat.com>
+ *
+ * Modified heavily by Joshua M. Thompson based on Dave Huang's NetBSD driver
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/crc32.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/macintosh.h>
+#include <asm/macints.h>
+#include <asm/mac_psc.h>
+#include <asm/page.h>
+#include "mace.h"
+
+#define N_TX_RING 1
+#define N_RX_RING 8
+#define N_RX_PAGES ((N_RX_RING * 0x0800 + PAGE_SIZE - 1) / PAGE_SIZE)
+#define TX_TIMEOUT HZ
+
+/* Bits in transmit DMA status */
+#define TX_DMA_ERR 0x80
+
+/* The MACE is simply wired down on a Mac68K box */
+
+#define MACE_BASE (void *)(0x50F1C000)
+#define MACE_PROM (void *)(0x50F08001)
+
+struct mace_data {
+ volatile struct mace *mace;
+ volatile unsigned char *tx_ring;
+ volatile unsigned char *tx_ring_phys;
+ volatile unsigned char *rx_ring;
+ volatile unsigned char *rx_ring_phys;
+ int dma_intr;
+ struct net_device_stats stats;
+ int rx_slot, rx_tail;
+ int tx_slot, tx_sloti, tx_count;
+};
+
+struct mace_frame {
+ u16 len;
+ u16 status;
+ u16 rntpc;
+ u16 rcvcc;
+ u32 pad1;
+ u32 pad2;
+ u8 data[1];
+ /* And frame continues.. */
+};
+
+#define PRIV_BYTES sizeof(struct mace_data)
+
+extern void psc_debug_dump(void);
+
+static int mace_open(struct net_device *dev);
+static int mace_close(struct net_device *dev);
+static int mace_xmit_start(struct sk_buff *skb, struct net_device *dev);
+static struct net_device_stats *mace_stats(struct net_device *dev);
+static void mace_set_multicast(struct net_device *dev);
+static int mace_set_address(struct net_device *dev, void *addr);
+static irqreturn_t mace_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static irqreturn_t mace_dma_intr(int irq, void *dev_id, struct pt_regs *regs);
+static void mace_tx_timeout(struct net_device *dev);
+
+/* Bit-reverse one byte of an ethernet hardware address. */
+
+static int bitrev(int b)
+{
+ int d = 0, i;
+
+ for (i = 0; i < 8; ++i, b >>= 1) {
+ d = (d << 1) | (b & 1);
+ }
+
+ return d;
+}
+
+/*
+ * Load a receive DMA channel with a base address and ring length
+ */
+
+static void mace_load_rxdma_base(struct net_device *dev, int set)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+
+ psc_write_word(PSC_ENETRD_CMD + set, 0x0100);
+ psc_write_long(PSC_ENETRD_ADDR + set, (u32) mp->rx_ring_phys);
+ psc_write_long(PSC_ENETRD_LEN + set, N_RX_RING);
+ psc_write_word(PSC_ENETRD_CMD + set, 0x9800);
+ mp->rx_tail = 0;
+}
+
+/*
+ * Reset the receive DMA subsystem
+ */
+
+static void mace_rxdma_reset(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mace = mp->mace;
+ u8 maccc = mace->maccc;
+
+ mace->maccc = maccc & ~ENRCV;
+
+ psc_write_word(PSC_ENETRD_CTL, 0x8800);
+ mace_load_rxdma_base(dev, 0x00);
+ psc_write_word(PSC_ENETRD_CTL, 0x0400);
+
+ psc_write_word(PSC_ENETRD_CTL, 0x8800);
+ mace_load_rxdma_base(dev, 0x10);
+ psc_write_word(PSC_ENETRD_CTL, 0x0400);
+
+ mace->maccc = maccc;
+ mp->rx_slot = 0;
+
+ psc_write_word(PSC_ENETRD_CMD + PSC_SET0, 0x9800);
+ psc_write_word(PSC_ENETRD_CMD + PSC_SET1, 0x9800);
+}
+
+/*
+ * Reset the transmit DMA subsystem
+ */
+
+static void mace_txdma_reset(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mace = mp->mace;
+ u8 maccc;
+
+ psc_write_word(PSC_ENETWR_CTL, 0x8800);
+
+ maccc = mace->maccc;
+ mace->maccc = maccc & ~ENXMT;
+
+ mp->tx_slot = mp->tx_sloti = 0;
+ mp->tx_count = N_TX_RING;
+
+ psc_write_word(PSC_ENETWR_CTL, 0x0400);
+ mace->maccc = maccc;
+}
+
+/*
+ * Disable DMA
+ */
+
+static void mace_dma_off(struct net_device *dev)
+{
+ psc_write_word(PSC_ENETRD_CTL, 0x8800);
+ psc_write_word(PSC_ENETRD_CTL, 0x1000);
+ psc_write_word(PSC_ENETRD_CMD + PSC_SET0, 0x1100);
+ psc_write_word(PSC_ENETRD_CMD + PSC_SET1, 0x1100);
+
+ psc_write_word(PSC_ENETWR_CTL, 0x8800);
+ psc_write_word(PSC_ENETWR_CTL, 0x1000);
+ psc_write_word(PSC_ENETWR_CMD + PSC_SET0, 0x1100);
+ psc_write_word(PSC_ENETWR_CMD + PSC_SET1, 0x1100);
+}
+
+/*
+ * Not really much of a probe. The hardware table tells us if this
+ * model of Macintrash has a MACE (AV macintoshes)
+ */
+
+struct net_device *mace_probe(int unit)
+{
+ int j;
+ struct mace_data *mp;
+ unsigned char *addr;
+ struct net_device *dev;
+ unsigned char checksum = 0;
+ static int found = 0;
+ int err;
+
+ if (found || macintosh_config->ether_type != MAC_ETHER_MACE)
+ return ERR_PTR(-ENODEV);
+
+ found = 1; /* prevent 'finding' one on every device probe */
+
+ dev = alloc_etherdev(PRIV_BYTES);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ if (unit >= 0)
+ sprintf(dev->name, "eth%d", unit);
+
+ mp = (struct mace_data *) dev->priv;
+ dev->base_addr = (u32)MACE_BASE;
+ mp->mace = (volatile struct mace *) MACE_BASE;
+
+ dev->irq = IRQ_MAC_MACE;
+ mp->dma_intr = IRQ_MAC_MACE_DMA;
+
+ /*
+ * The PROM contains 8 bytes which total 0xFF when XOR'd
+ * together. Due to the usual peculiar apple brain damage
+ * the bytes are spaced out in a strange boundary and the
+ * bits are reversed.
+ */
+
+ addr = (void *)MACE_PROM;
+
+ for (j = 0; j < 6; ++j) {
+ u8 v=bitrev(addr[j<<4]);
+ checksum ^= v;
+ dev->dev_addr[j] = v;
+ }
+ for (; j < 8; ++j) {
+ checksum ^= bitrev(addr[j<<4]);
+ }
+
+ if (checksum != 0xFF) {
+ free_netdev(dev);
+ return ERR_PTR(-ENODEV);
+ }
+
+ memset(&mp->stats, 0, sizeof(mp->stats));
+
+ dev->open = mace_open;
+ dev->stop = mace_close;
+ dev->hard_start_xmit = mace_xmit_start;
+ dev->tx_timeout = mace_tx_timeout;
+ dev->watchdog_timeo = TX_TIMEOUT;
+ dev->get_stats = mace_stats;
+ dev->set_multicast_list = mace_set_multicast;
+ dev->set_mac_address = mace_set_address;
+
+ printk(KERN_INFO "%s: 68K MACE, hardware address %.2X", dev->name, dev->dev_addr[0]);
+ for (j = 1 ; j < 6 ; j++) printk(":%.2X", dev->dev_addr[j]);
+ printk("\n");
+
+ err = register_netdev(dev);
+ if (!err)
+ return dev;
+
+ free_netdev(dev);
+ return ERR_PTR(err);
+}
+
+/*
+ * Load the address on a mace controller.
+ */
+
+static int mace_set_address(struct net_device *dev, void *addr)
+{
+ unsigned char *p = addr;
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+ int i;
+ unsigned long flags;
+ u8 maccc;
+
+ local_irq_save(flags);
+
+ maccc = mb->maccc;
+
+ /* load up the hardware address */
+ mb->iac = ADDRCHG | PHYADDR;
+ while ((mb->iac & ADDRCHG) != 0);
+
+ for (i = 0; i < 6; ++i) {
+ mb->padr = dev->dev_addr[i] = p[i];
+ }
+
+ mb->maccc = maccc;
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+/*
+ * Open the Macintosh MACE. Most of this is playing with the DMA
+ * engine. The ethernet chip is quite friendly.
+ */
+
+static int mace_open(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+#if 0
+ int i;
+
+ i = 200;
+ while (--i) {
+ mb->biucc = SWRST;
+ if (mb->biucc & SWRST) {
+ udelay(10);
+ continue;
+ }
+ break;
+ }
+ if (!i) {
+ printk(KERN_ERR "%s: software reset failed!!\n", dev->name);
+ return -EAGAIN;
+ }
+#endif
+
+ mb->biucc = XMTSP_64;
+ mb->fifocc = XMTFW_16 | RCVFW_64 | XMTFWU | RCVFWU | XMTBRST | RCVBRST;
+ mb->xmtfc = AUTO_PAD_XMIT;
+ mb->plscc = PORTSEL_AUI;
+ /* mb->utr = RTRD; */
+
+ if (request_irq(dev->irq, mace_interrupt, 0, dev->name, dev)) {
+ printk(KERN_ERR "%s: can't get irq %d\n", dev->name, dev->irq);
+ return -EAGAIN;
+ }
+ if (request_irq(mp->dma_intr, mace_dma_intr, 0, dev->name, dev)) {
+ printk(KERN_ERR "%s: can't get irq %d\n", dev->name, mp->dma_intr);
+ free_irq(dev->irq, dev);
+ return -EAGAIN;
+ }
+
+ /* Allocate the DMA ring buffers */
+
+ mp->rx_ring = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, N_RX_PAGES);
+ mp->tx_ring = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, 0);
+
+ if (mp->tx_ring==NULL || mp->rx_ring==NULL) {
+ if (mp->rx_ring) free_pages((u32) mp->rx_ring, N_RX_PAGES);
+ if (mp->tx_ring) free_pages((u32) mp->tx_ring, 0);
+ free_irq(dev->irq, dev);
+ free_irq(mp->dma_intr, dev);
+ printk(KERN_ERR "%s: unable to allocate DMA buffers\n", dev->name);
+ return -ENOMEM;
+ }
+
+ mp->rx_ring_phys = (unsigned char *) virt_to_bus((void *)mp->rx_ring);
+ mp->tx_ring_phys = (unsigned char *) virt_to_bus((void *)mp->tx_ring);
+
+ /* We want the Rx buffer to be uncached and the Tx buffer to be writethrough */
+
+ kernel_set_cachemode((void *)mp->rx_ring, N_RX_PAGES * PAGE_SIZE, IOMAP_NOCACHE_NONSER);
+ kernel_set_cachemode((void *)mp->tx_ring, PAGE_SIZE, IOMAP_WRITETHROUGH);
+
+ mace_dma_off(dev);
+
+ /* Not sure what these do */
+
+ psc_write_word(PSC_ENETWR_CTL, 0x9000);
+ psc_write_word(PSC_ENETRD_CTL, 0x9000);
+ psc_write_word(PSC_ENETWR_CTL, 0x0400);
+ psc_write_word(PSC_ENETRD_CTL, 0x0400);
+
+#if 0
+ /* load up the hardware address */
+
+ mb->iac = ADDRCHG | PHYADDR;
+
+ while ((mb->iac & ADDRCHG) != 0);
+
+ for (i = 0; i < 6; ++i)
+ mb->padr = dev->dev_addr[i];
+
+ /* clear the multicast filter */
+ mb->iac = ADDRCHG | LOGADDR;
+
+ while ((mb->iac & ADDRCHG) != 0);
+
+ for (i = 0; i < 8; ++i)
+ mb->ladrf = 0;
+
+ mb->plscc = PORTSEL_GPSI + ENPLSIO;
+
+ mb->maccc = ENXMT | ENRCV;
+ mb->imr = RCVINT;
+#endif
+
+ mace_rxdma_reset(dev);
+ mace_txdma_reset(dev);
+
+ return 0;
+}
+
+/*
+ * Shut down the mace and its interrupt channel
+ */
+
+static int mace_close(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+
+ mb->maccc = 0; /* disable rx and tx */
+ mb->imr = 0xFF; /* disable all irqs */
+ mace_dma_off(dev); /* disable rx and tx dma */
+
+ free_irq(dev->irq, dev);
+ free_irq(IRQ_MAC_MACE_DMA, dev);
+
+ free_pages((u32) mp->rx_ring, N_RX_PAGES);
+ free_pages((u32) mp->tx_ring, 0);
+
+ return 0;
+}
+
+/*
+ * Transmit a frame
+ */
+
+static int mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+
+ /* Stop the queue if the buffer is full */
+
+ if (!mp->tx_count) {
+ netif_stop_queue(dev);
+ return 1;
+ }
+ mp->tx_count--;
+
+ mp->stats.tx_packets++;
+ mp->stats.tx_bytes += skb->len;
+
+ /* We need to copy into our xmit buffer to take care of alignment and caching issues */
+
+ memcpy((void *) mp->tx_ring, skb->data, skb->len);
+
+ /* load the Tx DMA and fire it off */
+
+ psc_write_long(PSC_ENETWR_ADDR + mp->tx_slot, (u32) mp->tx_ring_phys);
+ psc_write_long(PSC_ENETWR_LEN + mp->tx_slot, skb->len);
+ psc_write_word(PSC_ENETWR_CMD + mp->tx_slot, 0x9800);
+
+ mp->tx_slot ^= 0x10;
+
+ dev_kfree_skb(skb);
+
+ return 0;
+}
+
+static struct net_device_stats *mace_stats(struct net_device *dev)
+{
+ struct mace_data *p = (struct mace_data *) dev->priv;
+ return &p->stats;
+}
+
+static void mace_set_multicast(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+ int i, j;
+ u32 crc;
+ u8 maccc;
+
+ maccc = mb->maccc;
+ mb->maccc &= ~PROM;
+
+ if (dev->flags & IFF_PROMISC) {
+ mb->maccc |= PROM;
+ } else {
+ unsigned char multicast_filter[8];
+ struct dev_mc_list *dmi = dev->mc_list;
+
+ if (dev->flags & IFF_ALLMULTI) {
+ for (i = 0; i < 8; i++) {
+ multicast_filter[i] = 0xFF;
+ }
+ } else {
+ for (i = 0; i < 8; i++)
+ multicast_filter[i] = 0;
+ for (i = 0; i < dev->mc_count; i++) {
+ crc = ether_crc_le(6, dmi->dmi_addr);
+ j = crc >> 26; /* bit number in multicast_filter */
+ multicast_filter[j >> 3] |= 1 << (j & 7);
+ dmi = dmi->next;
+ }
+ }
+
+ mb->iac = ADDRCHG | LOGADDR;
+ while (mb->iac & ADDRCHG);
+
+ for (i = 0; i < 8; ++i) {
+ mb->ladrf = multicast_filter[i];
+ }
+ }
+
+ mb->maccc = maccc;
+}
+
+/*
+ * Miscellaneous interrupts are handled here. We may end up
+ * having to bash the chip on the head for bad errors
+ */
+
+static void mace_handle_misc_intrs(struct mace_data *mp, int intr)
+{
+ volatile struct mace *mb = mp->mace;
+ static int mace_babbles, mace_jabbers;
+
+ if (intr & MPCO) {
+ mp->stats.rx_missed_errors += 256;
+ }
+ mp->stats.rx_missed_errors += mb->mpc; /* reading clears it */
+
+ if (intr & RNTPCO) {
+ mp->stats.rx_length_errors += 256;
+ }
+ mp->stats.rx_length_errors += mb->rntpc; /* reading clears it */
+
+ if (intr & CERR) {
+ ++mp->stats.tx_heartbeat_errors;
+ }
+ if (intr & BABBLE) {
+ if (mace_babbles++ < 4) {
+ printk(KERN_DEBUG "mace: babbling transmitter\n");
+ }
+ }
+ if (intr & JABBER) {
+ if (mace_jabbers++ < 4) {
+ printk(KERN_DEBUG "mace: jabbering transceiver\n");
+ }
+ }
+}
+
+/*
+ * A transmit error has occurred. (We kick the transmit side from
+ * the DMA completion)
+ */
+
+static void mace_xmit_error(struct net_device *dev)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+ u8 xmtfs, xmtrc;
+
+ xmtfs = mb->xmtfs;
+ xmtrc = mb->xmtrc;
+
+ if (xmtfs & XMTSV) {
+ if (xmtfs & UFLO) {
+ printk("%s: DMA underrun.\n", dev->name);
+ mp->stats.tx_errors++;
+ mp->stats.tx_fifo_errors++;
+ mace_txdma_reset(dev);
+ }
+ if (xmtfs & RTRY) {
+ mp->stats.collisions++;
+ }
+ }
+}
+
+/*
+ * A receive interrupt occurred.
+ */
+
+static void mace_recv_interrupt(struct net_device *dev)
+{
+/* struct mace_data *mp = (struct mace_data *) dev->priv; */
+// volatile struct mace *mb = mp->mace;
+}
+
+/*
+ * Process the chip interrupt
+ */
+
+static irqreturn_t mace_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct net_device *dev = (struct net_device *) dev_id;
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ volatile struct mace *mb = mp->mace;
+ u8 ir;
+
+ ir = mb->ir;
+ mace_handle_misc_intrs(mp, ir);
+
+ if (ir & XMTINT) {
+ mace_xmit_error(dev);
+ }
+ if (ir & RCVINT) {
+ mace_recv_interrupt(dev);
+ }
+ return IRQ_HANDLED;
+}
+
+static void mace_tx_timeout(struct net_device *dev)
+{
+/* struct mace_data *mp = (struct mace_data *) dev->priv; */
+// volatile struct mace *mb = mp->mace;
+}
+
+/*
+ * Handle a newly arrived frame
+ */
+
+static void mace_dma_rx_frame(struct net_device *dev, struct mace_frame *mf)
+{
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ struct sk_buff *skb;
+
+ if (mf->status & RS_OFLO) {
+ printk("%s: fifo overflow.\n", dev->name);
+ mp->stats.rx_errors++;
+ mp->stats.rx_fifo_errors++;
+ }
+ if (mf->status&(RS_CLSN|RS_FRAMERR|RS_FCSERR))
+ mp->stats.rx_errors++;
+
+ if (mf->status&RS_CLSN) {
+ mp->stats.collisions++;
+ }
+ if (mf->status&RS_FRAMERR) {
+ mp->stats.rx_frame_errors++;
+ }
+ if (mf->status&RS_FCSERR) {
+ mp->stats.rx_crc_errors++;
+ }
+
+ skb = dev_alloc_skb(mf->len+2);
+ if (!skb) {
+ mp->stats.rx_dropped++;
+ return;
+ }
+ skb_reserve(skb,2);
+ memcpy(skb_put(skb, mf->len), mf->data, mf->len);
+
+ skb->dev = dev;
+ skb->protocol = eth_type_trans(skb, dev);
+ netif_rx(skb);
+ dev->last_rx = jiffies;
+ mp->stats.rx_packets++;
+ mp->stats.rx_bytes += mf->len;
+}
+
+/*
+ * The PSC has passed us a DMA interrupt event.
+ */
+
+static irqreturn_t mace_dma_intr(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct net_device *dev = (struct net_device *) dev_id;
+ struct mace_data *mp = (struct mace_data *) dev->priv;
+ int left, head;
+ u16 status;
+ u32 baka;
+
+ /* Not sure what this does */
+
+ while ((baka = psc_read_long(PSC_MYSTERY)) != psc_read_long(PSC_MYSTERY));
+ if (!(baka & 0x60000000)) return IRQ_NONE;
+
+ /*
+ * Process the read queue
+ */
+
+ status = psc_read_word(PSC_ENETRD_CTL);
+
+ if (status & 0x2000) {
+ mace_rxdma_reset(dev);
+ } else if (status & 0x0100) {
+ psc_write_word(PSC_ENETRD_CMD + mp->rx_slot, 0x1100);
+
+ left = psc_read_long(PSC_ENETRD_LEN + mp->rx_slot);
+ head = N_RX_RING - left;
+
+ /* Loop through the ring buffer and process new packages */
+
+ while (mp->rx_tail < head) {
+ mace_dma_rx_frame(dev, (struct mace_frame *) (mp->rx_ring + (mp->rx_tail * 0x0800)));
+ mp->rx_tail++;
+ }
+
+ /* If we're out of buffers in this ring then switch to */
+ /* the other set, otherwise just reactivate this one. */
+
+ if (!left) {
+ mace_load_rxdma_base(dev, mp->rx_slot);
+ mp->rx_slot ^= 0x10;
+ } else {
+ psc_write_word(PSC_ENETRD_CMD + mp->rx_slot, 0x9800);
+ }
+ }
+
+ /*
+ * Process the write queue
+ */
+
+ status = psc_read_word(PSC_ENETWR_CTL);
+
+ if (status & 0x2000) {
+ mace_txdma_reset(dev);
+ } else if (status & 0x0100) {
+ psc_write_word(PSC_ENETWR_CMD + mp->tx_sloti, 0x0100);
+ mp->tx_sloti ^= 0x10;
+ mp->tx_count++;
+ netif_wake_queue(dev);
+ }
+ return IRQ_HANDLED;
+}
+
+MODULE_LICENSE("GPL");