m68k: macmace fixes

Fix a race condition in the transmit code, where the dma interrupt could update
the free tx buffer count concurrently and wedge the tx queue.

Fix the misuse of the rx frame status and rx frame length registers: no more
"fifo overrun" errors caused by the OFLOW bit being tested in the frame length
register (instead of the status register), and no more missed packets due to
incorrect length taken from status register (instead of the frame length
register).

Fix a panic (skb_over_panic BUG) caused by allocating and then copying an
incoming packet while the packet length register was changing.

Cut-and-paste the reset code from the powermac mace driver (mace.c), so the NIC
functions when MacOS does not initialise it (important for anyone wanting to
use the Emile boot loader).

Cut-and-paste the error counting and timeout recovery code from mace.c.

Fix over allocation of rx buffer memory (it's page order, not page count).

Converted to driver model.

Converted to DMA API.

Since I've run out of ways to make it fail, and since it performs well now,
promote the driver from EXPERIMENTAL status. Tested on both quadra 840av and
660av.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 364 insertions, 235 deletions

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 092e4cf07430..69dba62e0bad 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -337,8 +337,8 @@ config MACSONIC
 	  be called macsonic.
 
 config MACMACE
-	bool "Macintosh (AV) onboard MACE ethernet (EXPERIMENTAL)"
-	depends on NET_ETHERNET && MAC && EXPERIMENTAL
+	bool "Macintosh (AV) onboard MACE ethernet"
+	depends on NET_ETHERNET && MAC
 	select CRC32
 	help
 	  Support for the onboard AMD 79C940 MACE Ethernet controller used in
diff --git a/drivers/net/Space.c b/drivers/net/Space.c
index dd8ed456c8b2..1c3e293fbaf7 100644
--- a/drivers/net/Space.c
+++ b/drivers/net/Space.c
@@ -83,7 +83,6 @@ extern struct net_device *bagetlance_probe(int unit);
 extern struct net_device *mvme147lance_probe(int unit);
 extern struct net_device *tc515_probe(int unit);
 extern struct net_device *lance_probe(int unit);
-extern struct net_device *mace_probe(int unit);
 extern struct net_device *mac8390_probe(int unit);
 extern struct net_device *mac89x0_probe(int unit);
 extern struct net_device *mc32_probe(int unit);
@@ -274,9 +273,6 @@ static struct devprobe2 m68k_probes[] __initdata = {
 #ifdef CONFIG_MVME147_NET	/* MVME147 internal Ethernet */
 	{mvme147lance_probe, 0},
 #endif
-#ifdef CONFIG_MACMACE		/* Mac 68k Quadra AV builtin Ethernet */
-	{mace_probe, 0},
-#endif
 #ifdef CONFIG_MAC8390           /* NuBus NS8390-based cards */
 	{mac8390_probe, 0},
 #endif
diff --git a/drivers/net/macmace.c b/drivers/net/macmace.c
index 27911c07558d..fef3193121f9 100644
--- a/drivers/net/macmace.c
+++ b/drivers/net/macmace.c
@@ -12,6 +12,11 @@
  *	Copyright (C) 1998 Alan Cox <alan@redhat.com>
  *
  *	Modified heavily by Joshua M. Thompson based on Dave Huang's NetBSD driver
+ *
+ *	Copyright (C) 2007 Finn Thain
+ *
+ *	Converted to DMA API, converted to unified driver model,
+ *	sync'd some routines with mace.c and fixed various bugs.
  */
 
 
@@ -23,8 +28,9 @@
 #include <linux/string.h>
 #include <linux/crc32.h>
 #include <linux/bitrev.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
 #include <asm/io.h>
-#include <asm/pgtable.h>
 #include <asm/irq.h>
 #include <asm/macintosh.h>
 #include <asm/macints.h>
@@ -32,13 +38,20 @@
 #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)
+static char mac_mace_string[] = "macmace";
+static struct platform_device *mac_mace_device;
+
+#define N_TX_BUFF_ORDER	0
+#define N_TX_RING	(1 << N_TX_BUFF_ORDER)
+#define N_RX_BUFF_ORDER	3
+#define N_RX_RING	(1 << N_RX_BUFF_ORDER)
+
 #define TX_TIMEOUT	HZ
 
-/* Bits in transmit DMA status */
-#define TX_DMA_ERR	0x80
+#define MACE_BUFF_SIZE	0x800
+
+/* Chip rev needs workaround on HW & multicast addr change */
+#define BROKEN_ADDRCHG_REV	0x0941
 
 /* The MACE is simply wired down on a Mac68K box */
 
@@ -47,40 +60,46 @@
 
 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;
+	unsigned char *tx_ring;
+	dma_addr_t tx_ring_phys;
+	unsigned char *rx_ring;
+	dma_addr_t rx_ring_phys;
 	int dma_intr;
 	struct net_device_stats stats;
 	int rx_slot, rx_tail;
 	int tx_slot, tx_sloti, tx_count;
+	int chipid;
+	struct device *device;
 };
 
 struct mace_frame {
-	u16	len;
-	u16	status;
-	u16	rntpc;
-	u16	rcvcc;
-	u32	pad1;
-	u32	pad2;
+	u8	rcvcnt;
+	u8	pad1;
+	u8	rcvsts;
+	u8	pad2;
+	u8	rntpc;
+	u8	pad3;
+	u8	rcvcc;
+	u8	pad4;
+	u32	pad5;
+	u32	pad6;
 	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 void mace_reset(struct net_device *dev);
 static irqreturn_t mace_interrupt(int irq, void *dev_id);
 static irqreturn_t mace_dma_intr(int irq, void *dev_id);
 static void mace_tx_timeout(struct net_device *dev);
+static void __mace_set_address(struct net_device *dev, void *addr);
 
 /*
  * Load a receive DMA channel with a base address and ring length
@@ -88,7 +107,7 @@ static void mace_tx_timeout(struct net_device *dev);
 
 static void mace_load_rxdma_base(struct net_device *dev, int set)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 
 	psc_write_word(PSC_ENETRD_CMD + set, 0x0100);
 	psc_write_long(PSC_ENETRD_ADDR + set, (u32) mp->rx_ring_phys);
@@ -103,7 +122,7 @@ static void mace_load_rxdma_base(struct net_device *dev, int set)
 
 static void mace_rxdma_reset(struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mace = mp->mace;
 	u8 maccc = mace->maccc;
 
@@ -130,7 +149,7 @@ static void mace_rxdma_reset(struct net_device *dev)
 
 static void mace_txdma_reset(struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mace = mp->mace;
 	u8 maccc;
 
@@ -168,7 +187,7 @@ static void mace_dma_off(struct net_device *dev)
  * model of Macintrash has a MACE (AV macintoshes)
  */
 
-struct net_device *mace_probe(int unit)
+static int __devinit mace_probe(struct platform_device *pdev)
 {
 	int j;
 	struct mace_data *mp;
@@ -179,24 +198,28 @@ struct net_device *mace_probe(int unit)
 	int err;
 
 	if (found || macintosh_config->ether_type != MAC_ETHER_MACE)
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 
 	found = 1;	/* prevent 'finding' one on every device probe */
 
 	dev = alloc_etherdev(PRIV_BYTES);
 	if (!dev)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
-	if (unit >= 0)
-		sprintf(dev->name, "eth%d", unit);
+	mp = netdev_priv(dev);
+
+	mp->device = &pdev->dev;
+	SET_NETDEV_DEV(dev, &pdev->dev);
+ 	SET_MODULE_OWNER(dev);
 
-	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;
 
+	mp->chipid = mp->mace->chipid_hi << 8 | mp->mace->chipid_lo;
+
 	/*
 	 * The PROM contains 8 bytes which total 0xFF when XOR'd
 	 * together. Due to the usual peculiar apple brain damage
@@ -217,7 +240,7 @@ struct net_device *mace_probe(int unit)
 
 	if (checksum != 0xFF) {
 		free_netdev(dev);
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 	}
 
 	memset(&mp->stats, 0, sizeof(mp->stats));
@@ -237,22 +260,98 @@ struct net_device *mace_probe(int unit)
 
 	err = register_netdev(dev);
 	if (!err)
-		return dev;
+		return 0;
 
 	free_netdev(dev);
-	return ERR_PTR(err);
+	return err;
+}
+
+/*
+ * Reset the chip.
+ */
+
+static void mace_reset(struct net_device *dev)
+{
+	struct mace_data *mp = netdev_priv(dev);
+	volatile struct mace *mb = mp->mace;
+	int i;
+
+	/* soft-reset the chip */
+	i = 200;
+	while (--i) {
+		mb->biucc = SWRST;
+		if (mb->biucc & SWRST) {
+			udelay(10);
+			continue;
+		}
+		break;
+	}
+	if (!i) {
+		printk(KERN_ERR "macmace: cannot reset chip!\n");
+		return;
+	}
+
+	mb->maccc = 0;	/* turn off tx, rx */
+	mb->imr = 0xFF;	/* disable all intrs for now */
+	i = mb->ir;
+
+	mb->biucc = XMTSP_64;
+	mb->utr = RTRD;
+	mb->fifocc = XMTFW_8 | RCVFW_64 | XMTFWU | RCVFWU;
+
+	mb->xmtfc = AUTO_PAD_XMIT; /* auto-pad short frames */
+	mb->rcvfc = 0;
+
+	/* load up the hardware address */
+	__mace_set_address(dev, dev->dev_addr);
+
+	/* clear the multicast filter */
+	if (mp->chipid == BROKEN_ADDRCHG_REV)
+		mb->iac = LOGADDR;
+	else {
+		mb->iac = ADDRCHG | LOGADDR;
+		while ((mb->iac & ADDRCHG) != 0)
+			;
+	}
+	for (i = 0; i < 8; ++i)
+		mb->ladrf = 0;
+
+	/* done changing address */
+	if (mp->chipid != BROKEN_ADDRCHG_REV)
+		mb->iac = 0;
+
+	mb->plscc = PORTSEL_AUI;
 }
 
 /*
  * Load the address on a mace controller.
  */
 
-static int mace_set_address(struct net_device *dev, void *addr)
+static void __mace_set_address(struct net_device *dev, void *addr)
 {
-	unsigned char *p = addr;
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mb = mp->mace;
+	unsigned char *p = addr;
 	int i;
+
+	/* load up the hardware address */
+	if (mp->chipid == BROKEN_ADDRCHG_REV)
+		mb->iac = PHYADDR;
+	else {
+		mb->iac = ADDRCHG | PHYADDR;
+		while ((mb->iac & ADDRCHG) != 0)
+			;
+	}
+	for (i = 0; i < 6; ++i)
+		mb->padr = dev->dev_addr[i] = p[i];
+	if (mp->chipid != BROKEN_ADDRCHG_REV)
+		mb->iac = 0;
+}
+
+static int mace_set_address(struct net_device *dev, void *addr)
+{
+	struct mace_data *mp = netdev_priv(dev);
+	volatile struct mace *mb = mp->mace;
 	unsigned long flags;
 	u8 maccc;
 
@@ -260,15 +359,10 @@ static int mace_set_address(struct net_device *dev, void *addr)
 
 	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];
-	}
+	__mace_set_address(dev, addr);
 
 	mb->maccc = maccc;
+
 	local_irq_restore(flags);
 
 	return 0;
@@ -281,31 +375,11 @@ static int mace_set_address(struct net_device *dev, void *addr)
 
 static int mace_open(struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	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; */
+	/* reset the chip */
+	mace_reset(dev);
 
 	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);
@@ -319,25 +393,21 @@ static int mace_open(struct net_device *dev)
 
 	/* 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->tx_ring = dma_alloc_coherent(mp->device,
+			N_TX_RING * MACE_BUFF_SIZE,
+			&mp->tx_ring_phys, GFP_KERNEL);
+	if (mp->tx_ring == NULL) {
+		printk(KERN_ERR "%s: unable to allocate DMA tx buffers\n", dev->name);
+		goto out1;
 	}
 
-	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);
+	mp->rx_ring = dma_alloc_coherent(mp->device,
+			N_RX_RING * MACE_BUFF_SIZE,
+			&mp->rx_ring_phys, GFP_KERNEL);
+	if (mp->rx_ring == NULL) {
+		printk(KERN_ERR "%s: unable to allocate DMA rx buffers\n", dev->name);
+		goto out2;
+	}
 
 	mace_dma_off(dev);
 
@@ -348,34 +418,22 @@ static int mace_open(struct net_device *dev)
 	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);
 
+	/* turn it on! */
+	mb->maccc = ENXMT | ENRCV;
+	/* enable all interrupts except receive interrupts */
+	mb->imr = RCVINT;
 	return 0;
+
+out2:
+	dma_free_coherent(mp->device, N_TX_RING * MACE_BUFF_SIZE,
+	                  mp->tx_ring, mp->tx_ring_phys);
+out1:
+	free_irq(dev->irq, dev);
+	free_irq(mp->dma_intr, dev);
+	return -ENOMEM;
 }
 
 /*
@@ -384,19 +442,13 @@ static int mace_open(struct net_device *dev)
 
 static int mace_close(struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	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;
 }
 
@@ -406,15 +458,20 @@ static int mace_close(struct net_device *dev)
 
 static int mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
+	unsigned long flags;
 
-	/* Stop the queue if the buffer is full */
+	/* Stop the queue since there's only the one buffer */
 
+	local_irq_save(flags);
+	netif_stop_queue(dev);
 	if (!mp->tx_count) {
-		netif_stop_queue(dev);
-		return 1;
+		printk(KERN_ERR "macmace: tx queue running but no free buffers.\n");
+		local_irq_restore(flags);
+		return NETDEV_TX_BUSY;
 	}
 	mp->tx_count--;
+	local_irq_restore(flags);
 
 	mp->stats.tx_packets++;
 	mp->stats.tx_bytes += skb->len;
@@ -432,23 +489,26 @@ static int mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
 
 	dev_kfree_skb(skb);
 
-	return 0;
+	dev->trans_start = jiffies;
+	return NETDEV_TX_OK;
 }
 
 static struct net_device_stats *mace_stats(struct net_device *dev)
 {
-	struct mace_data *p = (struct mace_data *) dev->priv;
-	return &p->stats;
+	struct mace_data *mp = netdev_priv(dev);
+	return &mp->stats;
 }
 
 static void mace_set_multicast(struct net_device *dev)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mb = mp->mace;
 	int i, j;
 	u32 crc;
 	u8 maccc;
+	unsigned long flags;
 
+	local_irq_save(flags);
 	maccc = mb->maccc;
 	mb->maccc &= ~PROM;
 
@@ -473,116 +533,122 @@ static void mace_set_multicast(struct net_device *dev)
 			}
 		}
 
-		mb->iac = ADDRCHG | LOGADDR;
-		while (mb->iac & ADDRCHG);
-
-		for (i = 0; i < 8; ++i) {
-			mb->ladrf = multicast_filter[i];
+		if (mp->chipid == BROKEN_ADDRCHG_REV)
+			mb->iac = LOGADDR;
+		else {
+			mb->iac = ADDRCHG | LOGADDR;
+			while ((mb->iac & ADDRCHG) != 0)
+				;
 		}
+		for (i = 0; i < 8; ++i)
+			mb->ladrf = multicast_filter[i];
+		if (mp->chipid != BROKEN_ADDRCHG_REV)
+			mb->iac = 0;
 	}
 
 	mb->maccc = maccc;
+	local_irq_restore(flags);
 }
 
-/*
- * 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) {
+	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_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.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");
-		}
-	}
+	if (intr & BABBLE)
+		if (mace_babbles++ < 4)
+			printk(KERN_DEBUG "macmace: babbling transmitter\n");
+	if (intr & JABBER)
+		if (mace_jabbers++ < 4)
+			printk(KERN_DEBUG "macmace: 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)
+static irqreturn_t mace_interrupt(int irq, void *dev_id)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct net_device *dev = (struct net_device *) dev_id;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mb = mp->mace;
-	u8 xmtfs, xmtrc;
+	int intr, fs;
+	unsigned int flags;
 
-	xmtfs = mb->xmtfs;
-	xmtrc = mb->xmtrc;
+	/* don't want the dma interrupt handler to fire */
+	local_irq_save(flags);
 
-	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);
+	intr = mb->ir; /* read interrupt register */
+	mace_handle_misc_intrs(mp, intr);
+
+	if (intr & XMTINT) {
+		fs = mb->xmtfs;
+		if ((fs & XMTSV) == 0) {
+			printk(KERN_ERR "macmace: xmtfs not valid! (fs=%x)\n", fs);
+			mace_reset(dev);
+			/*
+			 * XXX mace likes to hang the machine after a xmtfs error.
+			 * This is hard to reproduce, reseting *may* help
+			 */
 		}
-		if (xmtfs & RTRY) {
-			mp->stats.collisions++;
+		/* dma should have finished */
+		if (!mp->tx_count) {
+			printk(KERN_DEBUG "macmace: tx ring ran out? (fs=%x)\n", fs);
+		}
+		/* Update stats */
+		if (fs & (UFLO|LCOL|LCAR|RTRY)) {
+			++mp->stats.tx_errors;
+			if (fs & LCAR)
+				++mp->stats.tx_carrier_errors;
+			else if (fs & (UFLO|LCOL|RTRY)) {
+				++mp->stats.tx_aborted_errors;
+				if (mb->xmtfs & UFLO) {
+					printk(KERN_ERR "%s: DMA underrun.\n", dev->name);
+					mp->stats.tx_fifo_errors++;
+					mace_txdma_reset(dev);
+				}
+			}
 		}
 	}
-}
 
-/*
- *	A receive interrupt occurred.
- */
+	if (mp->tx_count)
+		netif_wake_queue(dev);
 
-static void mace_recv_interrupt(struct net_device *dev)
-{
-/*	struct mace_data *mp = (struct mace_data *) dev->priv; */
-//	volatile struct mace *mb = mp->mace;
-}
+	local_irq_restore(flags);
 
-/*
- * Process the chip interrupt
- */
+	return IRQ_HANDLED;
+}
 
-static irqreturn_t mace_interrupt(int irq, void *dev_id)
+static void mace_tx_timeout(struct net_device *dev)
 {
-	struct net_device *dev = (struct net_device *) dev_id;
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	volatile struct mace *mb = mp->mace;
-	u8 ir;
+	unsigned long flags;
 
-	ir = mb->ir;
-	mace_handle_misc_intrs(mp, ir);
+	local_irq_save(flags);
 
-	if (ir & XMTINT) {
-		mace_xmit_error(dev);
-	}
-	if (ir & RCVINT) {
-		mace_recv_interrupt(dev);
-	}
-	return IRQ_HANDLED;
-}
+	/* turn off both tx and rx and reset the chip */
+	mb->maccc = 0;
+	printk(KERN_ERR "macmace: transmit timeout - resetting\n");
+	mace_txdma_reset(dev);
+	mace_reset(dev);
 
-static void mace_tx_timeout(struct net_device *dev)
-{
-/*	struct mace_data *mp = (struct mace_data *) dev->priv; */
-//	volatile struct mace *mb = mp->mace;
+	/* restart rx dma */
+	mace_rxdma_reset(dev);
+
+	mp->tx_count = N_TX_RING;
+	netif_wake_queue(dev);
+
+	/* turn it on! */
+	mb->maccc = ENXMT | ENRCV;
+	/* enable all interrupts except receive interrupts */
+	mb->imr = RCVINT;
+
+	local_irq_restore(flags);
 }
 
 /*
@@ -591,40 +657,39 @@ static void mace_tx_timeout(struct net_device *dev)
 
 static void mace_dma_rx_frame(struct net_device *dev, struct mace_frame *mf)
 {
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	struct sk_buff *skb;
+	unsigned int frame_status = mf->rcvsts;
 
-	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))
+	if (frame_status & (RS_OFLO | RS_CLSN | RS_FRAMERR | RS_FCSERR)) {
 		mp->stats.rx_errors++;
+		if (frame_status & RS_OFLO) {
+			printk(KERN_DEBUG "%s: fifo overflow.\n", dev->name);
+			mp->stats.rx_fifo_errors++;
+		}
+		if (frame_status & RS_CLSN)
+			mp->stats.collisions++;
+		if (frame_status & RS_FRAMERR)
+			mp->stats.rx_frame_errors++;
+		if (frame_status & RS_FCSERR)
+			mp->stats.rx_crc_errors++;
+	} else {
+		unsigned int frame_length = mf->rcvcnt + ((frame_status & 0x0F) << 8 );
 
-	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 = dev_alloc_skb(frame_length + 2);
+		if (!skb) {
+			mp->stats.rx_dropped++;
+			return;
+		}
+		skb_reserve(skb, 2);
+		memcpy(skb_put(skb, frame_length), mf->data, frame_length);
+
+		skb->protocol = eth_type_trans(skb, dev);
+		netif_rx(skb);
+		dev->last_rx = jiffies;
+		mp->stats.rx_packets++;
+		mp->stats.rx_bytes += frame_length;
 	}
-	skb_reserve(skb,2);
-	memcpy(skb_put(skb, mf->len), mf->data, mf->len);
-
-	skb->protocol = eth_type_trans(skb, dev);
-	netif_rx(skb);
-	dev->last_rx = jiffies;
-	mp->stats.rx_packets++;
-	mp->stats.rx_bytes += mf->len;
 }
 
 /*
@@ -634,7 +699,7 @@ static void mace_dma_rx_frame(struct net_device *dev, struct mace_frame *mf)
 static irqreturn_t mace_dma_intr(int irq, void *dev_id)
 {
 	struct net_device *dev = (struct net_device *) dev_id;
-	struct mace_data *mp = (struct mace_data *) dev->priv;
+	struct mace_data *mp = netdev_priv(dev);
 	int left, head;
 	u16 status;
 	u32 baka;
@@ -661,7 +726,8 @@ static irqreturn_t mace_dma_intr(int irq, void *dev_id)
 		/* 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)));
+			mace_dma_rx_frame(dev, (struct mace_frame*) (mp->rx_ring
+				+ (mp->rx_tail * MACE_BUFF_SIZE)));
 			mp->rx_tail++;
 		}
 
@@ -688,9 +754,76 @@ static irqreturn_t mace_dma_intr(int irq, void *dev_id)
 		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");
+MODULE_DESCRIPTION("Macintosh MACE ethernet driver");
+
+static int __devexit mac_mace_device_remove (struct platform_device *pdev)
+{
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct mace_data *mp = netdev_priv(dev);
+
+	unregister_netdev(dev);
+
+	free_irq(dev->irq, dev);
+	free_irq(IRQ_MAC_MACE_DMA, dev);
+
+	dma_free_coherent(mp->device, N_RX_RING * MACE_BUFF_SIZE,
+	                  mp->rx_ring, mp->rx_ring_phys);
+	dma_free_coherent(mp->device, N_TX_RING * MACE_BUFF_SIZE,
+	                  mp->tx_ring, mp->tx_ring_phys);
+
+	free_netdev(dev);
+
+	return 0;
+}
+
+static struct platform_driver mac_mace_driver = {
+	.probe  = mace_probe,
+	.remove = __devexit_p(mac_mace_device_remove),
+	.driver	= {
+		.name = mac_mace_string,
+	},
+};
+
+static int __init mac_mace_init_module(void)
+{
+	int err;
+
+	if ((err = platform_driver_register(&mac_mace_driver))) {
+		printk(KERN_ERR "Driver registration failed\n");
+		return err;
+	}
+
+	mac_mace_device = platform_device_alloc(mac_mace_string, 0);
+	if (!mac_mace_device)
+		goto out_unregister;
+
+	if (platform_device_add(mac_mace_device)) {
+		platform_device_put(mac_mace_device);
+		mac_mace_device = NULL;
+	}
+
+	return 0;
+
+out_unregister:
+	platform_driver_unregister(&mac_mace_driver);
+
+	return -ENOMEM;
+}
+
+static void __exit mac_mace_cleanup_module(void)
+{
+	platform_driver_unregister(&mac_mace_driver);
+
+	if (mac_mace_device) {
+		platform_device_unregister(mac_mace_device);
+		mac_mace_device = NULL;
+	}
+}
+
+module_init(mac_mace_init_module);
+module_exit(mac_mace_cleanup_module);