Linux-2.6.12-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!

1 files changed, 2024 insertions, 0 deletions

diff --git a/drivers/net/hamachi.c b/drivers/net/hamachi.c
new file mode 100644
index 000000000000..3d96714ed3cf
--- /dev/null
+++ b/drivers/net/hamachi.c
@@ -0,0 +1,2024 @@
+/* hamachi.c: A Packet Engines GNIC-II Gigabit Ethernet driver for Linux. */
+/*
+	Written 1998-2000 by Donald Becker.
+	Updates 2000 by Keith Underwood.
+
+	This software may be used and distributed according to the terms of 
+	the GNU General Public License (GPL), incorporated herein by reference.
+	Drivers based on or derived from this code fall under the GPL and must
+	retain the authorship, copyright and license notice.  This file is not
+	a complete program and may only be used when the entire operating
+	system is licensed under the GPL.
+
+	The author may be reached as becker@scyld.com, or C/O
+	Scyld Computing Corporation
+	410 Severn Ave., Suite 210
+	Annapolis MD 21403
+
+	This driver is for the Packet Engines GNIC-II PCI Gigabit Ethernet
+	adapter.
+
+	Support and updates available at
+	http://www.scyld.com/network/hamachi.html
+	or
+	http://www.parl.clemson.edu/~keithu/hamachi.html
+
+
+
+	Linux kernel changelog:
+
+	LK1.0.1:
+	- fix lack of pci_dev<->dev association
+	- ethtool support (jgarzik)
+
+*/
+
+#define DRV_NAME	"hamachi"
+#define DRV_VERSION	"1.01+LK1.0.1"
+#define DRV_RELDATE	"5/18/2001"
+
+
+/* A few user-configurable values. */
+
+static int debug = 1;		/* 1 normal messages, 0 quiet .. 7 verbose.  */
+#define final_version
+#define hamachi_debug debug
+/* Maximum events (Rx packets, etc.) to handle at each interrupt. */
+static int max_interrupt_work = 40;
+static int mtu;
+/* Default values selected by testing on a dual processor PIII-450 */
+/* These six interrupt control parameters may be set directly when loading the
+ * module, or through the rx_params and tx_params variables
+ */
+static int max_rx_latency = 0x11;
+static int max_rx_gap = 0x05;
+static int min_rx_pkt = 0x18;
+static int max_tx_latency = 0x00; 
+static int max_tx_gap = 0x00;
+static int min_tx_pkt = 0x30;
+
+/* Set the copy breakpoint for the copy-only-tiny-frames scheme.
+   -Setting to > 1518 causes all frames to be copied
+	-Setting to 0 disables copies
+*/
+static int rx_copybreak;
+
+/* An override for the hardware detection of bus width.
+	Set to 1 to force 32 bit PCI bus detection.  Set to 4 to force 64 bit.
+	Add 2 to disable parity detection.
+*/
+static int force32;
+
+
+/* Used to pass the media type, etc.
+   These exist for driver interoperability.
+   No media types are currently defined.
+		- The lower 4 bits are reserved for the media type.
+		- The next three bits may be set to one of the following:
+			0x00000000 : Autodetect PCI bus
+			0x00000010 : Force 32 bit PCI bus
+			0x00000020 : Disable parity detection
+			0x00000040 : Force 64 bit PCI bus
+			Default is autodetect
+		- The next bit can be used to force half-duplex.  This is a bad
+		  idea since no known implementations implement half-duplex, and,
+		  in general, half-duplex for gigabit ethernet is a bad idea.
+			0x00000080 : Force half-duplex 
+			Default is full-duplex.
+		- In the original driver, the ninth bit could be used to force
+		  full-duplex.  Maintain that for compatibility
+		   0x00000200 : Force full-duplex
+*/
+#define MAX_UNITS 8				/* More are supported, limit only on options */
+static int options[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
+static int full_duplex[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
+/* The Hamachi chipset supports 3 parameters each for Rx and Tx
+ * interruput management.  Parameters will be loaded as specified into
+ * the TxIntControl and RxIntControl registers.  
+ *
+ * The registers are arranged as follows:
+ *     23 - 16   15 -  8   7    -    0
+ *    _________________________________
+ *   | min_pkt | max_gap | max_latency |
+ *    ---------------------------------
+ *   min_pkt      : The minimum number of packets processed between
+ *                  interrupts. 
+ *   max_gap      : The maximum inter-packet gap in units of 8.192 us
+ *   max_latency  : The absolute time between interrupts in units of 8.192 us
+ * 
+ */
+static int rx_params[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
+static int tx_params[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
+
+/* Operational parameters that are set at compile time. */
+
+/* Keep the ring sizes a power of two for compile efficiency.
+	The compiler will convert <unsigned>'%'<2^N> into a bit mask.
+   Making the Tx ring too large decreases the effectiveness of channel
+   bonding and packet priority.
+   There are no ill effects from too-large receive rings, except for
+	excessive memory usage */
+/* Empirically it appears that the Tx ring needs to be a little bigger
+   for these Gbit adapters or you get into an overrun condition really
+   easily.  Also, things appear to work a bit better in back-to-back
+   configurations if the Rx ring is 8 times the size of the Tx ring
+*/
+#define TX_RING_SIZE	64
+#define RX_RING_SIZE	512
+#define TX_TOTAL_SIZE	TX_RING_SIZE*sizeof(struct hamachi_desc)
+#define RX_TOTAL_SIZE	RX_RING_SIZE*sizeof(struct hamachi_desc)
+
+/*
+ * Enable netdev_ioctl.  Added interrupt coalescing parameter adjustment.
+ * 2/19/99 Pete Wyckoff <wyckoff@ca.sandia.gov>
+ */
+
+/* play with 64-bit addrlen; seems to be a teensy bit slower  --pw */
+/* #define ADDRLEN 64 */
+
+/*
+ * RX_CHECKSUM turns on card-generated receive checksum generation for
+ *   TCP and UDP packets.  Otherwise the upper layers do the calculation.
+ * TX_CHECKSUM won't do anything too useful, even if it works.  There's no
+ *   easy mechanism by which to tell the TCP/UDP stack that it need not
+ *   generate checksums for this device.  But if somebody can find a way
+ *   to get that to work, most of the card work is in here already.
+ * 3/10/1999 Pete Wyckoff <wyckoff@ca.sandia.gov>
+ */
+#undef  TX_CHECKSUM
+#define RX_CHECKSUM
+
+/* Operational parameters that usually are not changed. */
+/* Time in jiffies before concluding the transmitter is hung. */
+#define TX_TIMEOUT  (5*HZ)
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/time.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ethtool.h>
+#include <linux/mii.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+
+#include <asm/uaccess.h>
+#include <asm/processor.h>	/* Processor type for cache alignment. */
+#include <asm/io.h>
+#include <asm/unaligned.h>
+#include <asm/cache.h>
+
+static char version[] __devinitdata =
+KERN_INFO DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE "  Written by Donald Becker\n"
+KERN_INFO "   Some modifications by Eric kasten <kasten@nscl.msu.edu>\n"
+KERN_INFO "   Further modifications by Keith Underwood <keithu@parl.clemson.edu>\n";
+
+
+/* IP_MF appears to be only defined in <netinet/ip.h>, however,
+   we need it for hardware checksumming support.  FYI... some of
+   the definitions in <netinet/ip.h> conflict/duplicate those in
+   other linux headers causing many compiler warnings.
+*/
+#ifndef IP_MF
+  #define IP_MF 0x2000   /* IP more frags from <netinet/ip.h> */ 
+#endif
+
+/* Define IP_OFFSET to be IPOPT_OFFSET */
+#ifndef IP_OFFSET
+  #ifdef IPOPT_OFFSET
+    #define IP_OFFSET IPOPT_OFFSET
+  #else
+    #define IP_OFFSET 2
+  #endif
+#endif
+
+#define RUN_AT(x) (jiffies + (x))
+
+/* Condensed bus+endian portability operations. */
+#if ADDRLEN == 64
+#define cpu_to_leXX(addr)	cpu_to_le64(addr)
+#else 
+#define cpu_to_leXX(addr)	cpu_to_le32(addr)
+#endif   
+
+
+/*
+				Theory of Operation
+
+I. Board Compatibility
+
+This device driver is designed for the Packet Engines "Hamachi"
+Gigabit Ethernet chip.  The only PCA currently supported is the GNIC-II 64-bit
+66Mhz PCI card.
+
+II. Board-specific settings
+
+No jumpers exist on the board.  The chip supports software correction of
+various motherboard wiring errors, however this driver does not support
+that feature.
+
+III. Driver operation
+
+IIIa. Ring buffers
+
+The Hamachi uses a typical descriptor based bus-master architecture.
+The descriptor list is similar to that used by the Digital Tulip.
+This driver uses two statically allocated fixed-size descriptor lists
+formed into rings by a branch from the final descriptor to the beginning of
+the list.  The ring sizes are set at compile time by RX/TX_RING_SIZE.
+
+This driver uses a zero-copy receive and transmit scheme similar my other
+network drivers.
+The driver allocates full frame size skbuffs for the Rx ring buffers at
+open() time and passes the skb->data field to the Hamachi as receive data
+buffers.  When an incoming frame is less than RX_COPYBREAK bytes long,
+a fresh skbuff is allocated and the frame is copied to the new skbuff.
+When the incoming frame is larger, the skbuff is passed directly up the
+protocol stack and replaced by a newly allocated skbuff.
+
+The RX_COPYBREAK value is chosen to trade-off the memory wasted by
+using a full-sized skbuff for small frames vs. the copying costs of larger
+frames.  Gigabit cards are typically used on generously configured machines
+and the underfilled buffers have negligible impact compared to the benefit of
+a single allocation size, so the default value of zero results in never
+copying packets.
+
+IIIb/c. Transmit/Receive Structure
+
+The Rx and Tx descriptor structure are straight-forward, with no historical
+baggage that must be explained.  Unlike the awkward DBDMA structure, there
+are no unused fields or option bits that had only one allowable setting.
+
+Two details should be noted about the descriptors: The chip supports both 32
+bit and 64 bit address structures, and the length field is overwritten on
+the receive descriptors.  The descriptor length is set in the control word
+for each channel. The development driver uses 32 bit addresses only, however
+64 bit addresses may be enabled for 64 bit architectures e.g. the Alpha.
+
+IIId. Synchronization
+
+This driver is very similar to my other network drivers.
+The driver runs as two independent, single-threaded flows of control.  One
+is the send-packet routine, which enforces single-threaded use by the
+dev->tbusy flag.  The other thread is the interrupt handler, which is single
+threaded by the hardware and other software.
+
+The send packet thread has partial control over the Tx ring and 'dev->tbusy'
+flag.  It sets the tbusy flag whenever it's queuing a Tx packet. If the next
+queue slot is empty, it clears the tbusy flag when finished otherwise it sets
+the 'hmp->tx_full' flag.
+
+The interrupt handler has exclusive control over the Rx ring and records stats
+from the Tx ring.  After reaping the stats, it marks the Tx queue entry as
+empty by incrementing the dirty_tx mark. Iff the 'hmp->tx_full' flag is set, it
+clears both the tx_full and tbusy flags.
+
+IV. Notes
+
+Thanks to Kim Stearns of Packet Engines for providing a pair of GNIC-II boards.
+
+IVb. References
+
+Hamachi Engineering Design Specification, 5/15/97
+(Note: This version was marked "Confidential".)
+
+IVc. Errata
+
+None noted.  
+
+V.  Recent Changes
+
+01/15/1999 EPK  Enlargement of the TX and RX ring sizes.  This appears 
+    to help avoid some stall conditions -- this needs further research.
+
+01/15/1999 EPK  Creation of the hamachi_tx function.  This function cleans 
+    the Tx ring and is called from hamachi_start_xmit (this used to be
+    called from hamachi_interrupt but it tends to delay execution of the
+    interrupt handler and thus reduce bandwidth by reducing the latency
+    between hamachi_rx()'s).  Notably, some modification has been made so 
+    that the cleaning loop checks only to make sure that the DescOwn bit 
+    isn't set in the status flag since the card is not required 
+    to set the entire flag to zero after processing.
+
+01/15/1999 EPK In the hamachi_start_tx function, the Tx ring full flag is 
+    checked before attempting to add a buffer to the ring.  If the ring is full
+    an attempt is made to free any dirty buffers and thus find space for
+    the new buffer or the function returns non-zero which should case the
+    scheduler to reschedule the buffer later.
+
+01/15/1999 EPK Some adjustments were made to the chip initialization.  
+    End-to-end flow control should now be fully active and the interrupt 
+    algorithm vars have been changed.  These could probably use further tuning.
+
+01/15/1999 EPK Added the max_{rx,tx}_latency options.  These are used to
+    set the rx and tx latencies for the Hamachi interrupts. If you're having
+    problems with network stalls, try setting these to higher values.
+    Valid values are 0x00 through 0xff.
+
+01/15/1999 EPK In general, the overall bandwidth has increased and 
+    latencies are better (sometimes by a factor of 2).  Stalls are rare at
+    this point, however there still appears to be a bug somewhere between the
+    hardware and driver.  TCP checksum errors under load also appear to be
+    eliminated at this point.
+
+01/18/1999 EPK Ensured that the DescEndRing bit was being set on both the
+    Rx and Tx rings.  This appears to have been affecting whether a particular
+    peer-to-peer connection would hang under high load.  I believe the Rx
+    rings was typically getting set correctly, but the Tx ring wasn't getting
+    the DescEndRing bit set during initialization. ??? Does this mean the
+    hamachi card is using the DescEndRing in processing even if a particular
+    slot isn't in use -- hypothetically, the card might be searching the 
+    entire Tx ring for slots with the DescOwn bit set and then processing
+    them.  If the DescEndRing bit isn't set, then it might just wander off
+    through memory until it hits a chunk of data with that bit set
+    and then looping back.
+
+02/09/1999 EPK Added Michel Mueller's TxDMA Interrupt and Tx-timeout 
+    problem (TxCmd and RxCmd need only to be set when idle or stopped.
+
+02/09/1999 EPK Added code to check/reset dev->tbusy in hamachi_interrupt.
+    (Michel Mueller pointed out the ``permanently busy'' potential 
+    problem here).
+
+02/22/1999 EPK Added Pete Wyckoff's ioctl to control the Tx/Rx latencies. 
+
+02/23/1999 EPK Verified that the interrupt status field bits for Tx were
+    incorrectly defined and corrected (as per Michel Mueller).
+
+02/23/1999 EPK Corrected the Tx full check to check that at least 4 slots
+    were available before reseting the tbusy and tx_full flags
+    (as per Michel Mueller).
+
+03/11/1999 EPK Added Pete Wyckoff's hardware checksumming support.
+
+12/31/1999 KDU Cleaned up assorted things and added Don's code to force
+32 bit.
+
+02/20/2000 KDU Some of the control was just plain odd.  Cleaned up the
+hamachi_start_xmit() and hamachi_interrupt() code.  There is still some
+re-structuring I would like to do.  
+
+03/01/2000 KDU Experimenting with a WIDE range of interrupt mitigation
+parameters on a dual P3-450 setup yielded the new default interrupt
+mitigation parameters.  Tx should interrupt VERY infrequently due to
+Eric's scheme.  Rx should be more often...
+
+03/13/2000 KDU Added a patch to make the Rx Checksum code interact
+nicely with non-linux machines.  
+
+03/13/2000 KDU Experimented with some of the configuration values:  
+
+	-It seems that enabling PCI performance commands for descriptors
+	(changing RxDMACtrl and TxDMACtrl lower nibble from 5 to D) has minimal 
+	performance impact for any of my tests. (ttcp, netpipe, netperf)  I will 
+	leave them that way until I hear further feedback.
+
+	-Increasing the PCI_LATENCY_TIMER to 130 
+	(2 + (burst size of 128 * (0 wait states + 1))) seems to slightly
+	degrade performance.  Leaving default at 64 pending further information.
+
+03/14/2000 KDU Further tuning:  
+
+	-adjusted boguscnt in hamachi_rx() to depend on interrupt
+	mitigation parameters chosen.
+
+	-Selected a set of interrupt parameters based on some extensive testing.  
+	These may change with more testing.
+
+TO DO:
+
+-Consider borrowing from the acenic driver code to check PCI_COMMAND for
+PCI_COMMAND_INVALIDATE.  Set maximum burst size to cache line size in
+that case.
+
+-fix the reset procedure.  It doesn't quite work.  
+*/
+
+/* A few values that may be tweaked. */
+/* Size of each temporary Rx buffer, calculated as:
+ * 1518 bytes (ethernet packet) + 2 bytes (to get 8 byte alignment for
+ * the card) + 8 bytes of status info + 8 bytes for the Rx Checksum +
+ * 2 more because we use skb_reserve.  
+ */
+#define PKT_BUF_SZ		1538
+
+/* For now, this is going to be set to the maximum size of an ethernet
+ * packet.  Eventually, we may want to make it a variable that is
+ * related to the MTU
+ */
+#define MAX_FRAME_SIZE  1518
+
+/* The rest of these values should never change. */
+
+static void hamachi_timer(unsigned long data);
+
+enum capability_flags {CanHaveMII=1, };
+static struct chip_info {
+	u16	vendor_id, device_id, device_id_mask, pad;
+	const char *name;
+	void (*media_timer)(unsigned long data);
+	int flags;
+} chip_tbl[] = {
+	{0x1318, 0x0911, 0xffff, 0, "Hamachi GNIC-II", hamachi_timer, 0},
+	{0,},
+};
+
+/* Offsets to the Hamachi registers.  Various sizes. */
+enum hamachi_offsets {
+	TxDMACtrl=0x00, TxCmd=0x04, TxStatus=0x06, TxPtr=0x08, TxCurPtr=0x10,
+	RxDMACtrl=0x20, RxCmd=0x24, RxStatus=0x26, RxPtr=0x28, RxCurPtr=0x30,
+	PCIClkMeas=0x060, MiscStatus=0x066, ChipRev=0x68, ChipReset=0x06B,
+	LEDCtrl=0x06C, VirtualJumpers=0x06D, GPIO=0x6E,
+	TxChecksum=0x074, RxChecksum=0x076,
+	TxIntrCtrl=0x078, RxIntrCtrl=0x07C,
+	InterruptEnable=0x080, InterruptClear=0x084, IntrStatus=0x088,
+	EventStatus=0x08C,
+	MACCnfg=0x0A0, FrameGap0=0x0A2, FrameGap1=0x0A4,
+	/* See enum MII_offsets below. */
+	MACCnfg2=0x0B0, RxDepth=0x0B8, FlowCtrl=0x0BC, MaxFrameSize=0x0CE,
+	AddrMode=0x0D0, StationAddr=0x0D2,
+	/* Gigabit AutoNegotiation. */
+	ANCtrl=0x0E0, ANStatus=0x0E2, ANXchngCtrl=0x0E4, ANAdvertise=0x0E8,
+	ANLinkPartnerAbility=0x0EA,
+	EECmdStatus=0x0F0, EEData=0x0F1, EEAddr=0x0F2,
+	FIFOcfg=0x0F8,
+};
+
+/* Offsets to the MII-mode registers. */
+enum MII_offsets {
+	MII_Cmd=0xA6, MII_Addr=0xA8, MII_Wr_Data=0xAA, MII_Rd_Data=0xAC,
+	MII_Status=0xAE,
+};
+
+/* Bits in the interrupt status/mask registers. */
+enum intr_status_bits {
+	IntrRxDone=0x01, IntrRxPCIFault=0x02, IntrRxPCIErr=0x04,
+	IntrTxDone=0x100, IntrTxPCIFault=0x200, IntrTxPCIErr=0x400,
+	LinkChange=0x10000, NegotiationChange=0x20000, StatsMax=0x40000, };
+
+/* The Hamachi Rx and Tx buffer descriptors. */
+struct hamachi_desc {
+	u32 status_n_length;			
+#if ADDRLEN == 64
+	u32 pad;
+	u64 addr;
+#else
+	u32 addr;
+#endif
+};
+
+/* Bits in hamachi_desc.status_n_length */
+enum desc_status_bits {
+	DescOwn=0x80000000, DescEndPacket=0x40000000, DescEndRing=0x20000000, 
+	DescIntr=0x10000000,
+};
+
+#define PRIV_ALIGN	15  			/* Required alignment mask */
+#define MII_CNT		4
+struct hamachi_private {
+	/* Descriptor rings first for alignment.  Tx requires a second descriptor
+	   for status. */
+	struct hamachi_desc *rx_ring;
+	struct hamachi_desc *tx_ring;
+	struct sk_buff* rx_skbuff[RX_RING_SIZE];
+	struct sk_buff* tx_skbuff[TX_RING_SIZE];
+	dma_addr_t tx_ring_dma;
+	dma_addr_t rx_ring_dma;
+	struct net_device_stats stats;
+	struct timer_list timer;		/* Media selection timer. */
+	/* Frequently used and paired value: keep adjacent for cache effect. */
+	spinlock_t lock;
+	int chip_id;
+	unsigned int cur_rx, dirty_rx;		/* Producer/consumer ring indices */
+	unsigned int cur_tx, dirty_tx;
+	unsigned int rx_buf_sz;			/* Based on MTU+slack. */
+	unsigned int tx_full:1;			/* The Tx queue is full. */
+	unsigned int duplex_lock:1;
+	unsigned int default_port:4;		/* Last dev->if_port value. */
+	/* MII transceiver section. */
+	int mii_cnt;								/* MII device addresses. */
+	struct mii_if_info mii_if;		/* MII lib hooks/info */
+	unsigned char phys[MII_CNT];		/* MII device addresses, only first one used. */
+	u32 rx_int_var, tx_int_var;	/* interrupt control variables */
+	u32 option;							/* Hold on to a copy of the options */
+	struct pci_dev *pci_dev;
+	void __iomem *base;
+};
+
+MODULE_AUTHOR("Donald Becker <becker@scyld.com>, Eric Kasten <kasten@nscl.msu.edu>, Keith Underwood <keithu@parl.clemson.edu>");
+MODULE_DESCRIPTION("Packet Engines 'Hamachi' GNIC-II Gigabit Ethernet driver");
+MODULE_LICENSE("GPL");
+
+module_param(max_interrupt_work, int, 0);
+module_param(mtu, int, 0);
+module_param(debug, int, 0);
+module_param(min_rx_pkt, int, 0);
+module_param(max_rx_gap, int, 0);
+module_param(max_rx_latency, int, 0);
+module_param(min_tx_pkt, int, 0);
+module_param(max_tx_gap, int, 0);
+module_param(max_tx_latency, int, 0);
+module_param(rx_copybreak, int, 0);
+module_param_array(rx_params, int, NULL, 0);
+module_param_array(tx_params, int, NULL, 0);
+module_param_array(options, int, NULL, 0);
+module_param_array(full_duplex, int, NULL, 0);
+module_param(force32, int, 0);
+MODULE_PARM_DESC(max_interrupt_work, "GNIC-II maximum events handled per interrupt");
+MODULE_PARM_DESC(mtu, "GNIC-II MTU (all boards)");
+MODULE_PARM_DESC(debug, "GNIC-II debug level (0-7)");
+MODULE_PARM_DESC(min_rx_pkt, "GNIC-II minimum Rx packets processed between interrupts");
+MODULE_PARM_DESC(max_rx_gap, "GNIC-II maximum Rx inter-packet gap in 8.192 microsecond units");
+MODULE_PARM_DESC(max_rx_latency, "GNIC-II time between Rx interrupts in 8.192 microsecond units");
+MODULE_PARM_DESC(min_tx_pkt, "GNIC-II minimum Tx packets processed between interrupts");
+MODULE_PARM_DESC(max_tx_gap, "GNIC-II maximum Tx inter-packet gap in 8.192 microsecond units");
+MODULE_PARM_DESC(max_tx_latency, "GNIC-II time between Tx interrupts in 8.192 microsecond units");
+MODULE_PARM_DESC(rx_copybreak, "GNIC-II copy breakpoint for copy-only-tiny-frames");
+MODULE_PARM_DESC(rx_params, "GNIC-II min_rx_pkt+max_rx_gap+max_rx_latency");
+MODULE_PARM_DESC(tx_params, "GNIC-II min_tx_pkt+max_tx_gap+max_tx_latency");
+MODULE_PARM_DESC(options, "GNIC-II Bits 0-3: media type, bits 4-6: as force32, bit 7: half duplex, bit 9 full duplex");
+MODULE_PARM_DESC(full_duplex, "GNIC-II full duplex setting(s) (1)");
+MODULE_PARM_DESC(force32, "GNIC-II: Bit 0: 32 bit PCI, bit 1: disable parity, bit 2: 64 bit PCI (all boards)");
+                                                                        
+static int read_eeprom(void __iomem *ioaddr, int location);
+static int mdio_read(struct net_device *dev, int phy_id, int location);
+static void mdio_write(struct net_device *dev, int phy_id, int location, int value);
+static int hamachi_open(struct net_device *dev);
+static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
+static void hamachi_timer(unsigned long data);
+static void hamachi_tx_timeout(struct net_device *dev);
+static void hamachi_init_ring(struct net_device *dev);
+static int hamachi_start_xmit(struct sk_buff *skb, struct net_device *dev);
+static irqreturn_t hamachi_interrupt(int irq, void *dev_instance, struct pt_regs *regs);
+static int hamachi_rx(struct net_device *dev);
+static inline int hamachi_tx(struct net_device *dev);
+static void hamachi_error(struct net_device *dev, int intr_status);
+static int hamachi_close(struct net_device *dev);
+static struct net_device_stats *hamachi_get_stats(struct net_device *dev);
+static void set_rx_mode(struct net_device *dev);
+static struct ethtool_ops ethtool_ops;
+static struct ethtool_ops ethtool_ops_no_mii;
+
+static int __devinit hamachi_init_one (struct pci_dev *pdev,
+				    const struct pci_device_id *ent)
+{
+	struct hamachi_private *hmp;
+	int option, i, rx_int_var, tx_int_var, boguscnt;
+	int chip_id = ent->driver_data;
+	int irq;
+	void __iomem *ioaddr;
+	unsigned long base;
+	static int card_idx;
+	struct net_device *dev;
+	void *ring_space;
+	dma_addr_t ring_dma;
+	int ret = -ENOMEM;
+
+/* when built into the kernel, we only print version if device is found */
+#ifndef MODULE
+	static int printed_version;
+	if (!printed_version++)
+		printk(version);
+#endif
+
+	if (pci_enable_device(pdev)) {
+		ret = -EIO;
+		goto err_out;
+	}
+
+	base = pci_resource_start(pdev, 0);
+#ifdef __alpha__				/* Really "64 bit addrs" */
+	base |= (pci_resource_start(pdev, 1) << 32);
+#endif
+
+	pci_set_master(pdev);
+
+	i = pci_request_regions(pdev, DRV_NAME);
+	if (i) return i;
+
+	irq = pdev->irq;
+	ioaddr = ioremap(base, 0x400);
+	if (!ioaddr)
+		goto err_out_release;
+
+	dev = alloc_etherdev(sizeof(struct hamachi_private));
+	if (!dev)
+		goto err_out_iounmap;
+
+	SET_MODULE_OWNER(dev);
+	SET_NETDEV_DEV(dev, &pdev->dev);
+
+#ifdef TX_CHECKSUM
+	printk("check that skbcopy in ip_queue_xmit isn't happening\n");
+	dev->hard_header_len += 8;  /* for cksum tag */
+#endif
+
+	for (i = 0; i < 6; i++)
+		dev->dev_addr[i] = 1 ? read_eeprom(ioaddr, 4 + i)
+			: readb(ioaddr + StationAddr + i);
+
+#if ! defined(final_version)
+	if (hamachi_debug > 4)
+		for (i = 0; i < 0x10; i++)
+			printk("%2.2x%s",
+				   read_eeprom(ioaddr, i), i % 16 != 15 ? " " : "\n");
+#endif
+
+	hmp = netdev_priv(dev);
+	spin_lock_init(&hmp->lock);
+
+	hmp->mii_if.dev = dev;
+	hmp->mii_if.mdio_read = mdio_read;
+	hmp->mii_if.mdio_write = mdio_write;
+	hmp->mii_if.phy_id_mask = 0x1f;
+	hmp->mii_if.reg_num_mask = 0x1f;
+
+	ring_space = pci_alloc_consistent(pdev, TX_TOTAL_SIZE, &ring_dma);
+	if (!ring_space)
+		goto err_out_cleardev;
+	hmp->tx_ring = (struct hamachi_desc *)ring_space;
+	hmp->tx_ring_dma = ring_dma;
+
+	ring_space = pci_alloc_consistent(pdev, RX_TOTAL_SIZE, &ring_dma);
+	if (!ring_space)
+		goto err_out_unmap_tx;
+	hmp->rx_ring = (struct hamachi_desc *)ring_space;
+	hmp->rx_ring_dma = ring_dma;
+
+	/* Check for options being passed in */
+	option = card_idx < MAX_UNITS ? options[card_idx] : 0;
+	if (dev->mem_start)
+		option = dev->mem_start;
+
+	/* If the bus size is misidentified, do the following. */
+	force32 = force32 ? force32 : 
+		((option  >= 0) ? ((option & 0x00000070) >> 4) : 0 );
+	if (force32)
+		writeb(force32, ioaddr + VirtualJumpers);
+
+	/* Hmmm, do we really need to reset the chip???. */
+	writeb(0x01, ioaddr + ChipReset);
+
+	/* After a reset, the clock speed measurement of the PCI bus will not
+	 * be valid for a moment.  Wait for a little while until it is.  If
+	 * it takes more than 10ms, forget it.
+	 */
+	udelay(10);	
+	i = readb(ioaddr + PCIClkMeas);
+	for (boguscnt = 0; (!(i & 0x080)) && boguscnt < 1000; boguscnt++){
+		udelay(10);	
+		i = readb(ioaddr + PCIClkMeas);	
+	}
+
+	hmp->base = ioaddr;
+	dev->base_addr = (unsigned long)ioaddr;
+	dev->irq = irq;
+	pci_set_drvdata(pdev, dev);
+
+	hmp->chip_id = chip_id;
+	hmp->pci_dev = pdev;
+
+	/* The lower four bits are the media type. */
+	if (option > 0) {
+		hmp->option = option;
+		if (option & 0x200)
+			hmp->mii_if.full_duplex = 1;
+		else if (option & 0x080)
+			hmp->mii_if.full_duplex = 0;
+		hmp->default_port = option & 15;
+		if (hmp->default_port)
+			hmp->mii_if.force_media = 1;
+	}
+	if (card_idx < MAX_UNITS  &&  full_duplex[card_idx] > 0)
+		hmp->mii_if.full_duplex = 1;
+
+	/* lock the duplex mode if someone specified a value */
+	if (hmp->mii_if.full_duplex || (option & 0x080))
+		hmp->duplex_lock = 1;
+
+	/* Set interrupt tuning parameters */
+	max_rx_latency = max_rx_latency & 0x00ff;
+	max_rx_gap = max_rx_gap & 0x00ff;
+	min_rx_pkt = min_rx_pkt & 0x00ff;
+	max_tx_latency = max_tx_latency & 0x00ff;
+	max_tx_gap = max_tx_gap & 0x00ff;
+	min_tx_pkt = min_tx_pkt & 0x00ff;
+
+	rx_int_var = card_idx < MAX_UNITS ? rx_params[card_idx] : -1;
+	tx_int_var = card_idx < MAX_UNITS ? tx_params[card_idx] : -1;
+	hmp->rx_int_var = rx_int_var >= 0 ? rx_int_var : 
+		(min_rx_pkt << 16 | max_rx_gap << 8 | max_rx_latency);
+	hmp->tx_int_var = tx_int_var >= 0 ? tx_int_var : 
+		(min_tx_pkt << 16 | max_tx_gap << 8 | max_tx_latency);
+
+
+	/* The Hamachi-specific entries in the device structure. */
+	dev->open = &hamachi_open;
+	dev->hard_start_xmit = &hamachi_start_xmit;
+	dev->stop = &hamachi_close;
+	dev->get_stats = &hamachi_get_stats;
+	dev->set_multicast_list = &set_rx_mode;
+	dev->do_ioctl = &netdev_ioctl;
+	if (chip_tbl[hmp->chip_id].flags & CanHaveMII)
+		SET_ETHTOOL_OPS(dev, &ethtool_ops);
+	else
+		SET_ETHTOOL_OPS(dev, &ethtool_ops_no_mii);
+	dev->tx_timeout = &hamachi_tx_timeout;
+	dev->watchdog_timeo = TX_TIMEOUT;
+	if (mtu)
+		dev->mtu = mtu;
+
+	i = register_netdev(dev);
+	if (i) {
+		ret = i;
+		goto err_out_unmap_rx;
+	}
+
+	printk(KERN_INFO "%s: %s type %x at %p, ",
+		   dev->name, chip_tbl[chip_id].name, readl(ioaddr + ChipRev),
+		   ioaddr);
+	for (i = 0; i < 5; i++)
+			printk("%2.2x:", dev->dev_addr[i]);
+	printk("%2.2x, IRQ %d.\n", dev->dev_addr[i], irq);
+	i = readb(ioaddr + PCIClkMeas);
+	printk(KERN_INFO "%s:  %d-bit %d Mhz PCI bus (%d), Virtual Jumpers "
+		   "%2.2x, LPA %4.4x.\n",
+		   dev->name, readw(ioaddr + MiscStatus) & 1 ? 64 : 32,
+		   i ? 2000/(i&0x7f) : 0, i&0x7f, (int)readb(ioaddr + VirtualJumpers),
+		   readw(ioaddr + ANLinkPartnerAbility));
+
+	if (chip_tbl[hmp->chip_id].flags & CanHaveMII) {
+		int phy, phy_idx = 0;
+		for (phy = 0; phy < 32 && phy_idx < MII_CNT; phy++) {
+			int mii_status = mdio_read(dev, phy, MII_BMSR);
+			if (mii_status != 0xffff  &&
+				mii_status != 0x0000) {
+				hmp->phys[phy_idx++] = phy;
+				hmp->mii_if.advertising = mdio_read(dev, phy, MII_ADVERTISE);
+				printk(KERN_INFO "%s: MII PHY found at address %d, status "
+					   "0x%4.4x advertising %4.4x.\n",
+					   dev->name, phy, mii_status, hmp->mii_if.advertising);
+			}
+		}
+		hmp->mii_cnt = phy_idx;
+		if (hmp->mii_cnt > 0)
+			hmp->mii_if.phy_id = hmp->phys[0];
+		else
+			memset(&hmp->mii_if, 0, sizeof(hmp->mii_if));
+	}
+	/* Configure gigabit autonegotiation. */
+	writew(0x0400, ioaddr + ANXchngCtrl);	/* Enable legacy links. */
+	writew(0x08e0, ioaddr + ANAdvertise);	/* Set our advertise word. */
+	writew(0x1000, ioaddr + ANCtrl);			/* Enable negotiation */
+
+	card_idx++;
+	return 0;
+
+err_out_unmap_rx:
+	pci_free_consistent(pdev, RX_TOTAL_SIZE, hmp->rx_ring, 
+		hmp->rx_ring_dma);
+err_out_unmap_tx:
+	pci_free_consistent(pdev, TX_TOTAL_SIZE, hmp->tx_ring, 
+		hmp->tx_ring_dma);
+err_out_cleardev:
+	free_netdev (dev);
+err_out_iounmap:
+	iounmap(ioaddr);
+err_out_release:
+	pci_release_regions(pdev);
+err_out:
+	return ret;
+}
+
+static int __devinit read_eeprom(void __iomem *ioaddr, int location)
+{
+	int bogus_cnt = 1000;
+
+	/* We should check busy first - per docs -KDU */
+	while ((readb(ioaddr + EECmdStatus) & 0x40)  && --bogus_cnt > 0);
+	writew(location, ioaddr + EEAddr);
+	writeb(0x02, ioaddr + EECmdStatus);
+	bogus_cnt = 1000;
+	while ((readb(ioaddr + EECmdStatus) & 0x40)  && --bogus_cnt > 0);
+	if (hamachi_debug > 5)
+		printk("   EEPROM status is %2.2x after %d ticks.\n",
+			   (int)readb(ioaddr + EECmdStatus), 1000- bogus_cnt);
+	return readb(ioaddr + EEData);
+}
+
+/* MII Managemen Data I/O accesses.
+   These routines assume the MDIO controller is idle, and do not exit until
+   the command is finished. */
+
+static int mdio_read(struct net_device *dev, int phy_id, int location)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	int i;
+
+	/* We should check busy first - per docs -KDU */
+	for (i = 10000; i >= 0; i--)
+		if ((readw(ioaddr + MII_Status) & 1) == 0)
+			break;
+	writew((phy_id<<8) + location, ioaddr + MII_Addr);
+	writew(0x0001, ioaddr + MII_Cmd);
+	for (i = 10000; i >= 0; i--)
+		if ((readw(ioaddr + MII_Status) & 1) == 0)
+			break;
+	return readw(ioaddr + MII_Rd_Data);
+}
+
+static void mdio_write(struct net_device *dev, int phy_id, int location, int value)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	int i;
+
+	/* We should check busy first - per docs -KDU */
+	for (i = 10000; i >= 0; i--)
+		if ((readw(ioaddr + MII_Status) & 1) == 0)
+			break;
+	writew((phy_id<<8) + location, ioaddr + MII_Addr);
+	writew(value, ioaddr + MII_Wr_Data);
+
+	/* Wait for the command to finish. */
+	for (i = 10000; i >= 0; i--)
+		if ((readw(ioaddr + MII_Status) & 1) == 0)
+			break;
+	return;
+}
+
+
+static int hamachi_open(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	int i;
+	u32 rx_int_var, tx_int_var;
+	u16 fifo_info;
+
+	i = request_irq(dev->irq, &hamachi_interrupt, SA_SHIRQ, dev->name, dev);
+	if (i)
+		return i;
+
+	if (hamachi_debug > 1)
+		printk(KERN_DEBUG "%s: hamachi_open() irq %d.\n",
+			   dev->name, dev->irq);
+
+	hamachi_init_ring(dev);
+
+#if ADDRLEN == 64
+	/* writellll anyone ? */
+	writel(cpu_to_le64(hmp->rx_ring_dma), ioaddr + RxPtr);
+	writel(cpu_to_le64(hmp->rx_ring_dma) >> 32, ioaddr + RxPtr + 4);
+	writel(cpu_to_le64(hmp->tx_ring_dma), ioaddr + TxPtr);
+	writel(cpu_to_le64(hmp->tx_ring_dma) >> 32, ioaddr + TxPtr + 4);
+#else
+	writel(cpu_to_le32(hmp->rx_ring_dma), ioaddr + RxPtr);
+	writel(cpu_to_le32(hmp->tx_ring_dma), ioaddr + TxPtr);
+#endif
+
+	/* TODO:  It would make sense to organize this as words since the card 
+	 * documentation does. -KDU
+	 */
+	for (i = 0; i < 6; i++)
+		writeb(dev->dev_addr[i], ioaddr + StationAddr + i);
+
+	/* Initialize other registers: with so many this eventually this will
+	   converted to an offset/value list. */
+
+	/* Configure the FIFO */
+	fifo_info = (readw(ioaddr + GPIO) & 0x00C0) >> 6;
+	switch (fifo_info){
+		case 0 : 
+			/* No FIFO */
+			writew(0x0000, ioaddr + FIFOcfg);
+			break;
+		case 1 : 
+			/* Configure the FIFO for 512K external, 16K used for Tx. */
+			writew(0x0028, ioaddr + FIFOcfg);
+			break;
+		case 2 : 
+			/* Configure the FIFO for 1024 external, 32K used for Tx. */
+			writew(0x004C, ioaddr + FIFOcfg);
+			break;
+		case 3 : 
+			/* Configure the FIFO for 2048 external, 32K used for Tx. */
+			writew(0x006C, ioaddr + FIFOcfg);
+			break;
+		default : 
+			printk(KERN_WARNING "%s:  Unsupported external memory config!\n",
+				dev->name);
+			/* Default to no FIFO */
+			writew(0x0000, ioaddr + FIFOcfg);
+			break;
+	}
+	
+	if (dev->if_port == 0)
+		dev->if_port = hmp->default_port;
+
+
+	/* Setting the Rx mode will start the Rx process. */
+	/* If someone didn't choose a duplex, default to full-duplex */ 
+	if (hmp->duplex_lock != 1)
+		hmp->mii_if.full_duplex = 1;
+
+	/* always 1, takes no more time to do it */
+	writew(0x0001, ioaddr + RxChecksum);
+#ifdef TX_CHECKSUM
+	writew(0x0001, ioaddr + TxChecksum);
+#else
+	writew(0x0000, ioaddr + TxChecksum);
+#endif
+	writew(0x8000, ioaddr + MACCnfg); /* Soft reset the MAC */
+	writew(0x215F, ioaddr + MACCnfg);
+	writew(0x000C, ioaddr + FrameGap0); 
+	/* WHAT?!?!?  Why isn't this documented somewhere? -KDU */
+	writew(0x1018, ioaddr + FrameGap1);
+	/* Why do we enable receives/transmits here? -KDU */
+	writew(0x0780, ioaddr + MACCnfg2); /* Upper 16 bits control LEDs. */
+	/* Enable automatic generation of flow control frames, period 0xffff. */
+	writel(0x0030FFFF, ioaddr + FlowCtrl);
+	writew(MAX_FRAME_SIZE, ioaddr + MaxFrameSize); 	/* dev->mtu+14 ??? */
+
+	/* Enable legacy links. */
+	writew(0x0400, ioaddr + ANXchngCtrl);	/* Enable legacy links. */
+	/* Initial Link LED to blinking red. */
+	writeb(0x03, ioaddr + LEDCtrl);
+
+	/* Configure interrupt mitigation.  This has a great effect on
+	   performance, so systems tuning should start here!. */
+
+	rx_int_var = hmp->rx_int_var;
+	tx_int_var = hmp->tx_int_var;
+
+	if (hamachi_debug > 1) {
+		printk("max_tx_latency: %d, max_tx_gap: %d, min_tx_pkt: %d\n",
+			tx_int_var & 0x00ff, (tx_int_var & 0x00ff00) >> 8, 
+			(tx_int_var & 0x00ff0000) >> 16);
+		printk("max_rx_latency: %d, max_rx_gap: %d, min_rx_pkt: %d\n",
+			rx_int_var & 0x00ff, (rx_int_var & 0x00ff00) >> 8, 
+			(rx_int_var & 0x00ff0000) >> 16);
+		printk("rx_int_var: %x, tx_int_var: %x\n", rx_int_var, tx_int_var);
+	}
+
+	writel(tx_int_var, ioaddr + TxIntrCtrl); 
+	writel(rx_int_var, ioaddr + RxIntrCtrl); 
+
+	set_rx_mode(dev);
+
+	netif_start_queue(dev);
+
+	/* Enable interrupts by setting the interrupt mask. */
+	writel(0x80878787, ioaddr + InterruptEnable);
+	writew(0x0000, ioaddr + EventStatus);	/* Clear non-interrupting events */
+
+	/* Configure and start the DMA channels. */
+	/* Burst sizes are in the low three bits: size = 4<<(val&7) */
+#if ADDRLEN == 64
+	writew(0x005D, ioaddr + RxDMACtrl); 		/* 128 dword bursts */
+	writew(0x005D, ioaddr + TxDMACtrl);
+#else
+	writew(0x001D, ioaddr + RxDMACtrl);
+	writew(0x001D, ioaddr + TxDMACtrl);
+#endif
+	writew(0x0001, ioaddr + RxCmd);
+
+	if (hamachi_debug > 2) {
+		printk(KERN_DEBUG "%s: Done hamachi_open(), status: Rx %x Tx %x.\n",
+			   dev->name, readw(ioaddr + RxStatus), readw(ioaddr + TxStatus));
+	}
+	/* Set the timer to check for link beat. */
+	init_timer(&hmp->timer);
+	hmp->timer.expires = RUN_AT((24*HZ)/10);			/* 2.4 sec. */
+	hmp->timer.data = (unsigned long)dev;
+	hmp->timer.function = &hamachi_timer;				/* timer handler */
+	add_timer(&hmp->timer);
+
+	return 0;
+}
+
+static inline int hamachi_tx(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+
+	/* Update the dirty pointer until we find an entry that is
+		still owned by the card */
+	for (; hmp->cur_tx - hmp->dirty_tx > 0; hmp->dirty_tx++) {
+		int entry = hmp->dirty_tx % TX_RING_SIZE;
+		struct sk_buff *skb;
+
+		if (hmp->tx_ring[entry].status_n_length & cpu_to_le32(DescOwn)) 
+			break;
+		/* Free the original skb. */
+		skb = hmp->tx_skbuff[entry];
+		if (skb != 0) {
+			pci_unmap_single(hmp->pci_dev, 
+				hmp->tx_ring[entry].addr, skb->len, 
+				PCI_DMA_TODEVICE);
+			dev_kfree_skb(skb);
+			hmp->tx_skbuff[entry] = NULL;
+		}
+		hmp->tx_ring[entry].status_n_length = 0;
+		if (entry >= TX_RING_SIZE-1) 
+			hmp->tx_ring[TX_RING_SIZE-1].status_n_length |=
+				cpu_to_le32(DescEndRing);   
+		hmp->stats.tx_packets++;
+	}
+
+	return 0;
+}
+
+static void hamachi_timer(unsigned long data)
+{
+	struct net_device *dev = (struct net_device *)data;
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	int next_tick = 10*HZ;
+
+	if (hamachi_debug > 2) {
+		printk(KERN_INFO "%s: Hamachi Autonegotiation status %4.4x, LPA "
+			   "%4.4x.\n", dev->name, readw(ioaddr + ANStatus),
+			   readw(ioaddr + ANLinkPartnerAbility));
+		printk(KERN_INFO "%s: Autonegotiation regs %4.4x %4.4x %4.4x "
+		       "%4.4x %4.4x %4.4x.\n", dev->name,
+		       readw(ioaddr + 0x0e0),
+		       readw(ioaddr + 0x0e2),
+		       readw(ioaddr + 0x0e4),
+		       readw(ioaddr + 0x0e6),
+		       readw(ioaddr + 0x0e8),
+		       readw(ioaddr + 0x0eA));
+	}
+	/* We could do something here... nah. */
+	hmp->timer.expires = RUN_AT(next_tick);
+	add_timer(&hmp->timer);
+}
+
+static void hamachi_tx_timeout(struct net_device *dev)
+{
+	int i;
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+
+	printk(KERN_WARNING "%s: Hamachi transmit timed out, status %8.8x,"
+		   " resetting...\n", dev->name, (int)readw(ioaddr + TxStatus));
+
+	{
+		int i;
+		printk(KERN_DEBUG "  Rx ring %p: ", hmp->rx_ring);
+		for (i = 0; i < RX_RING_SIZE; i++)
+			printk(" %8.8x", (unsigned int)hmp->rx_ring[i].status_n_length);
+		printk("\n"KERN_DEBUG"  Tx ring %p: ", hmp->tx_ring);
+		for (i = 0; i < TX_RING_SIZE; i++)
+			printk(" %4.4x", hmp->tx_ring[i].status_n_length);
+		printk("\n");
+	}
+
+	/* Reinit the hardware and make sure the Rx and Tx processes 
+		are up and running.
+	 */
+	dev->if_port = 0;
+	/* The right way to do Reset. -KDU
+	 *		-Clear OWN bit in all Rx/Tx descriptors
+	 *		-Wait 50 uS for channels to go idle
+	 *		-Turn off MAC receiver
+	 *		-Issue Reset
+	 */
+	
+	for (i = 0; i < RX_RING_SIZE; i++)
+		hmp->rx_ring[i].status_n_length &= cpu_to_le32(~DescOwn);
+
+	/* Presume that all packets in the Tx queue are gone if we have to
+	 * re-init the hardware.
+	 */
+	for (i = 0; i < TX_RING_SIZE; i++){
+		struct sk_buff *skb;
+
+		if (i >= TX_RING_SIZE - 1)
+			hmp->tx_ring[i].status_n_length = cpu_to_le32(
+				DescEndRing |
+				(hmp->tx_ring[i].status_n_length & 0x0000FFFF));
+		else	
+			hmp->tx_ring[i].status_n_length &= 0x0000ffff;
+		skb = hmp->tx_skbuff[i];
+		if (skb){
+			pci_unmap_single(hmp->pci_dev, hmp->tx_ring[i].addr, 
+				skb->len, PCI_DMA_TODEVICE);
+			dev_kfree_skb(skb);
+			hmp->tx_skbuff[i] = NULL;
+		}
+	}
+
+	udelay(60); /* Sleep 60 us just for safety sake */
+	writew(0x0002, ioaddr + RxCmd); /* STOP Rx */
+		
+	writeb(0x01, ioaddr + ChipReset);  /* Reinit the hardware */ 
+
+	hmp->tx_full = 0;
+	hmp->cur_rx = hmp->cur_tx = 0;
+	hmp->dirty_rx = hmp->dirty_tx = 0;
+	/* Rx packets are also presumed lost; however, we need to make sure a
+	 * ring of buffers is in tact. -KDU
+	 */ 
+	for (i = 0; i < RX_RING_SIZE; i++){
+		struct sk_buff *skb = hmp->rx_skbuff[i];
+
+		if (skb){
+			pci_unmap_single(hmp->pci_dev, hmp->rx_ring[i].addr, 
+				hmp->rx_buf_sz, PCI_DMA_FROMDEVICE);
+			dev_kfree_skb(skb);
+			hmp->rx_skbuff[i] = NULL;
+		}
+	}
+	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz);
+		hmp->rx_skbuff[i] = skb;
+		if (skb == NULL)
+			break;
+		skb->dev = dev;         /* Mark as being used by this device. */
+		skb_reserve(skb, 2); /* 16 byte align the IP header. */
+                hmp->rx_ring[i].addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
+			skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+		hmp->rx_ring[i].status_n_length = cpu_to_le32(DescOwn | 
+			DescEndPacket | DescIntr | (hmp->rx_buf_sz - 2));
+	}
+	hmp->dirty_rx = (unsigned int)(i - RX_RING_SIZE);
+	/* Mark the last entry as wrapping the ring. */
+	hmp->rx_ring[RX_RING_SIZE-1].status_n_length |= cpu_to_le32(DescEndRing);
+
+	/* Trigger an immediate transmit demand. */
+	dev->trans_start = jiffies;
+	hmp->stats.tx_errors++;
+
+	/* Restart the chip's Tx/Rx processes . */
+	writew(0x0002, ioaddr + TxCmd); /* STOP Tx */
+	writew(0x0001, ioaddr + TxCmd); /* START Tx */
+	writew(0x0001, ioaddr + RxCmd); /* START Rx */
+
+	netif_wake_queue(dev);
+}
+
+
+/* Initialize the Rx and Tx rings, along with various 'dev' bits. */
+static void hamachi_init_ring(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	int i;
+
+	hmp->tx_full = 0;
+	hmp->cur_rx = hmp->cur_tx = 0;
+	hmp->dirty_rx = hmp->dirty_tx = 0;
+
+#if 0
+	/* This is wrong.  I'm not sure what the original plan was, but this
+	 * is wrong.  An MTU of 1 gets you a buffer of 1536, while an MTU
+	 * of 1501 gets a buffer of 1533? -KDU
+	 */
+	hmp->rx_buf_sz = (dev->mtu <= 1500 ? PKT_BUF_SZ : dev->mtu + 32);
+#endif
+	/* My attempt at a reasonable correction */
+	/* +26 gets the maximum ethernet encapsulation, +7 & ~7 because the
+	 * card needs room to do 8 byte alignment, +2 so we can reserve 
+	 * the first 2 bytes, and +16 gets room for the status word from the 
+	 * card.  -KDU
+	 */
+	hmp->rx_buf_sz = (dev->mtu <= 1492 ? PKT_BUF_SZ : 
+		(((dev->mtu+26+7) & ~7) + 2 + 16));
+
+	/* Initialize all Rx descriptors. */
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		hmp->rx_ring[i].status_n_length = 0;
+		hmp->rx_skbuff[i] = NULL;
+	}
+	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz);
+		hmp->rx_skbuff[i] = skb;
+		if (skb == NULL)
+			break;
+		skb->dev = dev;         /* Mark as being used by this device. */
+		skb_reserve(skb, 2); /* 16 byte align the IP header. */
+                hmp->rx_ring[i].addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
+			skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+		/* -2 because it doesn't REALLY have that first 2 bytes -KDU */
+		hmp->rx_ring[i].status_n_length = cpu_to_le32(DescOwn | 
+			DescEndPacket | DescIntr | (hmp->rx_buf_sz -2));
+	}
+	hmp->dirty_rx = (unsigned int)(i - RX_RING_SIZE);
+	hmp->rx_ring[RX_RING_SIZE-1].status_n_length |= cpu_to_le32(DescEndRing);
+
+	for (i = 0; i < TX_RING_SIZE; i++) {
+		hmp->tx_skbuff[i] = NULL;
+		hmp->tx_ring[i].status_n_length = 0;
+	}
+	/* Mark the last entry of the ring */
+	hmp->tx_ring[TX_RING_SIZE-1].status_n_length |= cpu_to_le32(DescEndRing);
+
+	return;
+}
+
+
+#ifdef TX_CHECKSUM
+#define csum_add(it, val) \
+do { \
+    it += (u16) (val); \
+    if (it & 0xffff0000) { \
+	it &= 0xffff; \
+	++it; \
+    } \
+} while (0)
+    /* printk("add %04x --> %04x\n", val, it); \ */
+
+/* uh->len already network format, do not swap */
+#define pseudo_csum_udp(sum,ih,uh) do { \
+    sum = 0; \
+    csum_add(sum, (ih)->saddr >> 16); \
+    csum_add(sum, (ih)->saddr & 0xffff); \
+    csum_add(sum, (ih)->daddr >> 16); \
+    csum_add(sum, (ih)->daddr & 0xffff); \
+    csum_add(sum, __constant_htons(IPPROTO_UDP)); \
+    csum_add(sum, (uh)->len); \
+} while (0)
+
+/* swap len */
+#define pseudo_csum_tcp(sum,ih,len) do { \
+    sum = 0; \
+    csum_add(sum, (ih)->saddr >> 16); \
+    csum_add(sum, (ih)->saddr & 0xffff); \
+    csum_add(sum, (ih)->daddr >> 16); \
+    csum_add(sum, (ih)->daddr & 0xffff); \
+    csum_add(sum, __constant_htons(IPPROTO_TCP)); \
+    csum_add(sum, htons(len)); \
+} while (0)
+#endif
+
+static int hamachi_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	unsigned entry;
+	u16 status;
+
+	/* Ok, now make sure that the queue has space before trying to 
+		add another skbuff.  if we return non-zero the scheduler
+		should interpret this as a queue full and requeue the buffer
+		for later.
+	 */
+	if (hmp->tx_full) {
+		/* We should NEVER reach this point -KDU */
+		printk(KERN_WARNING "%s: Hamachi transmit queue full at slot %d.\n",dev->name, hmp->cur_tx);
+
+		/* Wake the potentially-idle transmit channel. */
+		/* If we don't need to read status, DON'T -KDU */
+		status=readw(hmp->base + TxStatus);
+		if( !(status & 0x0001) || (status & 0x0002))
+			writew(0x0001, hmp->base + TxCmd);
+		return 1;
+	} 
+
+	/* Caution: the write order is important here, set the field
+	   with the "ownership" bits last. */
+
+	/* Calculate the next Tx descriptor entry. */
+	entry = hmp->cur_tx % TX_RING_SIZE;
+
+	hmp->tx_skbuff[entry] = skb;
+
+#ifdef TX_CHECKSUM
+	{
+	    /* tack on checksum tag */
+	    u32 tagval = 0;
+	    struct ethhdr *eh = (struct ethhdr *)skb->data;
+	    if (eh->h_proto == __constant_htons(ETH_P_IP)) {
+		struct iphdr *ih = (struct iphdr *)((char *)eh + ETH_HLEN);
+		if (ih->protocol == IPPROTO_UDP) {
+		    struct udphdr *uh
+		      = (struct udphdr *)((char *)ih + ih->ihl*4);
+		    u32 offset = ((unsigned char *)uh + 6) - skb->data;
+		    u32 pseudo;
+		    pseudo_csum_udp(pseudo, ih, uh);
+		    pseudo = htons(pseudo);
+		    printk("udp cksum was %04x, sending pseudo %04x\n",
+		      uh->check, pseudo);
+		    uh->check = 0;  /* zero out uh->check before card calc */
+		    /*
+		     * start at 14 (skip ethhdr), store at offset (uh->check),
+		     * use pseudo value given.
+		     */
+		    tagval = (14 << 24) | (offset << 16) | pseudo;
+		} else if (ih->protocol == IPPROTO_TCP) {
+		    printk("tcp, no auto cksum\n");
+		}
+	    }
+	    *(u32 *)skb_push(skb, 8) = tagval;
+	}
+#endif
+
+        hmp->tx_ring[entry].addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
+		skb->data, skb->len, PCI_DMA_TODEVICE));
+    
+	/* Hmmmm, could probably put a DescIntr on these, but the way
+		the driver is currently coded makes Tx interrupts unnecessary
+		since the clearing of the Tx ring is handled by the start_xmit
+		routine.  This organization helps mitigate the interrupts a
+		bit and probably renders the max_tx_latency param useless.
+		
+		Update: Putting a DescIntr bit on all of the descriptors and
+		mitigating interrupt frequency with the tx_min_pkt parameter. -KDU
+	*/
+	if (entry >= TX_RING_SIZE-1)		 /* Wrap ring */
+		hmp->tx_ring[entry].status_n_length = cpu_to_le32(DescOwn |
+			DescEndPacket | DescEndRing | DescIntr | skb->len);
+	else
+		hmp->tx_ring[entry].status_n_length = cpu_to_le32(DescOwn |
+			DescEndPacket | DescIntr | skb->len);
+	hmp->cur_tx++;
+
+	/* Non-x86 Todo: explicitly flush cache lines here. */
+
+	/* Wake the potentially-idle transmit channel. */
+	/* If we don't need to read status, DON'T -KDU */
+	status=readw(hmp->base + TxStatus);
+	if( !(status & 0x0001) || (status & 0x0002))
+		writew(0x0001, hmp->base + TxCmd);
+
+	/* Immediately before returning, let's clear as many entries as we can. */
+	hamachi_tx(dev);
+
+	/* We should kick the bottom half here, since we are not accepting
+	 * interrupts with every packet.  i.e. realize that Gigabit ethernet
+	 * can transmit faster than ordinary machines can load packets;
+	 * hence, any packet that got put off because we were in the transmit
+	 * routine should IMMEDIATELY get a chance to be re-queued. -KDU
+	 */
+	if ((hmp->cur_tx - hmp->dirty_tx) < (TX_RING_SIZE - 4)) 
+		netif_wake_queue(dev);  /* Typical path */
+	else {
+		hmp->tx_full = 1;
+		netif_stop_queue(dev);
+	}
+	dev->trans_start = jiffies;
+
+	if (hamachi_debug > 4) {
+		printk(KERN_DEBUG "%s: Hamachi transmit frame #%d queued in slot %d.\n",
+			   dev->name, hmp->cur_tx, entry);
+	}
+	return 0;
+}
+
+/* The interrupt handler does all of the Rx thread work and cleans up
+   after the Tx thread. */
+static irqreturn_t hamachi_interrupt(int irq, void *dev_instance, struct pt_regs *rgs)
+{
+	struct net_device *dev = dev_instance;
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	long boguscnt = max_interrupt_work;
+	int handled = 0;
+
+#ifndef final_version			/* Can never occur. */
+	if (dev == NULL) {
+		printk (KERN_ERR "hamachi_interrupt(): irq %d for unknown device.\n", irq);
+		return IRQ_NONE;
+	}
+#endif
+
+	spin_lock(&hmp->lock);
+
+	do {
+		u32 intr_status = readl(ioaddr + InterruptClear);
+
+		if (hamachi_debug > 4)
+			printk(KERN_DEBUG "%s: Hamachi interrupt, status %4.4x.\n",
+				   dev->name, intr_status);
+
+		if (intr_status == 0)
+			break;
+
+		handled = 1;
+
+		if (intr_status & IntrRxDone)
+			hamachi_rx(dev);
+
+		if (intr_status & IntrTxDone){
+			/* This code should RARELY need to execute. After all, this is
+			 * a gigabit link, it should consume packets as fast as we put
+			 * them in AND we clear the Tx ring in hamachi_start_xmit().
+			 */ 
+			if (hmp->tx_full){
+				for (; hmp->cur_tx - hmp->dirty_tx > 0; hmp->dirty_tx++){
+					int entry = hmp->dirty_tx % TX_RING_SIZE;
+					struct sk_buff *skb;
+
+					if (hmp->tx_ring[entry].status_n_length & cpu_to_le32(DescOwn)) 
+						break;
+					skb = hmp->tx_skbuff[entry];
+					/* Free the original skb. */
+					if (skb){
+						pci_unmap_single(hmp->pci_dev, 
+							hmp->tx_ring[entry].addr, 
+							skb->len,
+							PCI_DMA_TODEVICE);
+						dev_kfree_skb_irq(skb);
+						hmp->tx_skbuff[entry] = NULL;
+					}
+					hmp->tx_ring[entry].status_n_length = 0;
+					if (entry >= TX_RING_SIZE-1)  
+						hmp->tx_ring[TX_RING_SIZE-1].status_n_length |= 
+							cpu_to_le32(DescEndRing);
+					hmp->stats.tx_packets++;
+				}
+				if (hmp->cur_tx - hmp->dirty_tx < TX_RING_SIZE - 4){
+					/* The ring is no longer full */
+					hmp->tx_full = 0;
+					netif_wake_queue(dev);
+				}
+			} else {
+				netif_wake_queue(dev);
+			}
+		}
+
+
+		/* Abnormal error summary/uncommon events handlers. */
+		if (intr_status &
+			(IntrTxPCIFault | IntrTxPCIErr | IntrRxPCIFault | IntrRxPCIErr |
+			 LinkChange | NegotiationChange | StatsMax))
+			hamachi_error(dev, intr_status);
+
+		if (--boguscnt < 0) {
+			printk(KERN_WARNING "%s: Too much work at interrupt, status=0x%4.4x.\n",
+				   dev->name, intr_status);
+			break;
+		}
+	} while (1);
+
+	if (hamachi_debug > 3)
+		printk(KERN_DEBUG "%s: exiting interrupt, status=%#4.4x.\n",
+			   dev->name, readl(ioaddr + IntrStatus));
+
+#ifndef final_version
+	/* Code that should never be run!  Perhaps remove after testing.. */
+	{
+		static int stopit = 10;
+		if (dev->start == 0  &&  --stopit < 0) {
+			printk(KERN_ERR "%s: Emergency stop, looping startup interrupt.\n",
+				   dev->name);
+			free_irq(irq, dev);
+		}
+	}
+#endif
+
+	spin_unlock(&hmp->lock);
+	return IRQ_RETVAL(handled);
+}
+
+/* This routine is logically part of the interrupt handler, but separated
+   for clarity and better register allocation. */
+static int hamachi_rx(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	int entry = hmp->cur_rx % RX_RING_SIZE;
+	int boguscnt = (hmp->dirty_rx + RX_RING_SIZE) - hmp->cur_rx;
+
+	if (hamachi_debug > 4) {
+		printk(KERN_DEBUG " In hamachi_rx(), entry %d status %4.4x.\n",
+			   entry, hmp->rx_ring[entry].status_n_length);
+	}
+
+	/* If EOP is set on the next entry, it's a new packet. Send it up. */
+	while (1) {
+		struct hamachi_desc *desc = &(hmp->rx_ring[entry]);
+		u32 desc_status = le32_to_cpu(desc->status_n_length);
+		u16 data_size = desc_status;	/* Implicit truncate */
+		u8 *buf_addr; 
+		s32 frame_status;
+		
+		if (desc_status & DescOwn)
+			break;
+		pci_dma_sync_single_for_cpu(hmp->pci_dev,
+					    desc->addr,
+					    hmp->rx_buf_sz,
+					    PCI_DMA_FROMDEVICE);
+		buf_addr = (u8 *) hmp->rx_skbuff[entry]->tail;
+		frame_status = le32_to_cpu(get_unaligned((s32*)&(buf_addr[data_size - 12])));
+		if (hamachi_debug > 4)
+			printk(KERN_DEBUG "  hamachi_rx() status was %8.8x.\n",
+				frame_status);
+		if (--boguscnt < 0)
+			break;
+		if ( ! (desc_status & DescEndPacket)) {
+			printk(KERN_WARNING "%s: Oversized Ethernet frame spanned "
+				   "multiple buffers, entry %#x length %d status %4.4x!\n",
+				   dev->name, hmp->cur_rx, data_size, desc_status);
+			printk(KERN_WARNING "%s: Oversized Ethernet frame %p vs %p.\n",
+				   dev->name, desc, &hmp->rx_ring[hmp->cur_rx % RX_RING_SIZE]);
+			printk(KERN_WARNING "%s: Oversized Ethernet frame -- next status %x/%x last status %x.\n",
+				   dev->name,
+				   hmp->rx_ring[(hmp->cur_rx+1) % RX_RING_SIZE].status_n_length & 0xffff0000,
+				   hmp->rx_ring[(hmp->cur_rx+1) % RX_RING_SIZE].status_n_length & 0x0000ffff,
+				   hmp->rx_ring[(hmp->cur_rx-1) % RX_RING_SIZE].status_n_length);
+			hmp->stats.rx_length_errors++;
+		} /* else  Omit for prototype errata??? */
+		if (frame_status & 0x00380000) {
+			/* There was an error. */
+			if (hamachi_debug > 2)
+				printk(KERN_DEBUG "  hamachi_rx() Rx error was %8.8x.\n",
+					   frame_status);
+			hmp->stats.rx_errors++;
+			if (frame_status & 0x00600000) hmp->stats.rx_length_errors++;
+			if (frame_status & 0x00080000) hmp->stats.rx_frame_errors++;
+			if (frame_status & 0x00100000) hmp->stats.rx_crc_errors++;
+			if (frame_status < 0) hmp->stats.rx_dropped++;
+		} else {
+			struct sk_buff *skb;
+			/* Omit CRC */
+			u16 pkt_len = (frame_status & 0x07ff) - 4;	
+#ifdef RX_CHECKSUM
+			u32 pfck = *(u32 *) &buf_addr[data_size - 8];
+#endif
+
+
+#ifndef final_version
+			if (hamachi_debug > 4)
+				printk(KERN_DEBUG "  hamachi_rx() normal Rx pkt length %d"
+					   " of %d, bogus_cnt %d.\n",
+					   pkt_len, data_size, boguscnt);
+			if (hamachi_debug > 5)
+				printk(KERN_DEBUG"%s:  rx status %8.8x %8.8x %8.8x %8.8x %8.8x.\n",
+					   dev->name,
+					   *(s32*)&(buf_addr[data_size - 20]),
+					   *(s32*)&(buf_addr[data_size - 16]),
+					   *(s32*)&(buf_addr[data_size - 12]),
+					   *(s32*)&(buf_addr[data_size - 8]),
+					   *(s32*)&(buf_addr[data_size - 4]));
+#endif
+			/* Check if the packet is long enough to accept without copying
+			   to a minimally-sized skbuff. */
+			if (pkt_len < rx_copybreak
+				&& (skb = dev_alloc_skb(pkt_len + 2)) != NULL) {
+#ifdef RX_CHECKSUM
+				printk(KERN_ERR "%s: rx_copybreak non-zero "
+				  "not good with RX_CHECKSUM\n", dev->name);
+#endif
+				skb->dev = dev;
+				skb_reserve(skb, 2);	/* 16 byte align the IP header */
+				pci_dma_sync_single_for_cpu(hmp->pci_dev,
+							    hmp->rx_ring[entry].addr,
+							    hmp->rx_buf_sz,
+							    PCI_DMA_FROMDEVICE);
+				/* Call copy + cksum if available. */
+#if 1 || USE_IP_COPYSUM
+				eth_copy_and_sum(skb, 
+					hmp->rx_skbuff[entry]->data, pkt_len, 0);
+				skb_put(skb, pkt_len);
+#else
+				memcpy(skb_put(skb, pkt_len), hmp->rx_ring_dma
+					+ entry*sizeof(*desc), pkt_len);
+#endif
+				pci_dma_sync_single_for_device(hmp->pci_dev,
+							       hmp->rx_ring[entry].addr,
+							       hmp->rx_buf_sz,
+							       PCI_DMA_FROMDEVICE);
+			} else {
+				pci_unmap_single(hmp->pci_dev, 
+						 hmp->rx_ring[entry].addr,
+						 hmp->rx_buf_sz, PCI_DMA_FROMDEVICE);
+				skb_put(skb = hmp->rx_skbuff[entry], pkt_len);
+				hmp->rx_skbuff[entry] = NULL;
+			}
+			skb->protocol = eth_type_trans(skb, dev);
+
+
+#ifdef RX_CHECKSUM
+			/* TCP or UDP on ipv4, DIX encoding */
+			if (pfck>>24 == 0x91 || pfck>>24 == 0x51) {
+				struct iphdr *ih = (struct iphdr *) skb->data;
+				/* Check that IP packet is at least 46 bytes, otherwise,
+				 * there may be pad bytes included in the hardware checksum.
+				 * This wouldn't happen if everyone padded with 0.
+				 */
+				if (ntohs(ih->tot_len) >= 46){
+					/* don't worry about frags */
+					if (!(ih->frag_off & __constant_htons(IP_MF|IP_OFFSET))) {
+						u32 inv = *(u32 *) &buf_addr[data_size - 16];
+						u32 *p = (u32 *) &buf_addr[data_size - 20];
+						register u32 crc, p_r, p_r1;
+
+						if (inv & 4) {
+							inv &= ~4;
+							--p;
+						}
+						p_r = *p;
+						p_r1 = *(p-1);
+						switch (inv) {
+							case 0:	
+								crc = (p_r & 0xffff) + (p_r >> 16);
+								break;
+							case 1:	
+								crc = (p_r >> 16) + (p_r & 0xffff)
+									+ (p_r1 >> 16 & 0xff00); 
+								break;
+							case 2:	
+								crc = p_r + (p_r1 >> 16); 
+								break;
+							case 3:	
+								crc = p_r + (p_r1 & 0xff00) + (p_r1 >> 16); 
+								break;
+							default:	/*NOTREACHED*/ crc = 0;
+						}
+						if (crc & 0xffff0000) {
+							crc &= 0xffff;
+							++crc;
+						}
+						/* tcp/udp will add in pseudo */
+						skb->csum = ntohs(pfck & 0xffff);
+						if (skb->csum > crc)
+							skb->csum -= crc;
+						else
+							skb->csum += (~crc & 0xffff);
+						/*
+						* could do the pseudo myself and return
+						* CHECKSUM_UNNECESSARY
+						*/
+						skb->ip_summed = CHECKSUM_HW;
+					}
+				}	
+			}
+#endif  /* RX_CHECKSUM */
+
+			netif_rx(skb);
+			dev->last_rx = jiffies;
+			hmp->stats.rx_packets++;
+		}
+		entry = (++hmp->cur_rx) % RX_RING_SIZE;
+	}
+
+	/* Refill the Rx ring buffers. */
+	for (; hmp->cur_rx - hmp->dirty_rx > 0; hmp->dirty_rx++) {
+		struct hamachi_desc *desc;
+
+		entry = hmp->dirty_rx % RX_RING_SIZE;
+		desc = &(hmp->rx_ring[entry]);
+		if (hmp->rx_skbuff[entry] == NULL) {
+			struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz);
+
+			hmp->rx_skbuff[entry] = skb;
+			if (skb == NULL)
+				break;		/* Better luck next round. */
+			skb->dev = dev;		/* Mark as being used by this device. */
+			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
+                	desc->addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
+				skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+		}
+		desc->status_n_length = cpu_to_le32(hmp->rx_buf_sz);
+		if (entry >= RX_RING_SIZE-1)
+			desc->status_n_length |= cpu_to_le32(DescOwn | 
+				DescEndPacket | DescEndRing | DescIntr);
+		else
+			desc->status_n_length |= cpu_to_le32(DescOwn | 
+				DescEndPacket | DescIntr);
+	}
+
+	/* Restart Rx engine if stopped. */
+	/* If we don't need to check status, don't. -KDU */
+	if (readw(hmp->base + RxStatus) & 0x0002)
+		writew(0x0001, hmp->base + RxCmd);
+
+	return 0;
+}
+
+/* This is more properly named "uncommon interrupt events", as it covers more
+   than just errors. */
+static void hamachi_error(struct net_device *dev, int intr_status)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+
+	if (intr_status & (LinkChange|NegotiationChange)) {
+		if (hamachi_debug > 1)
+			printk(KERN_INFO "%s: Link changed: AutoNegotiation Ctrl"
+				   " %4.4x, Status %4.4x %4.4x Intr status %4.4x.\n",
+				   dev->name, readw(ioaddr + 0x0E0), readw(ioaddr + 0x0E2),
+				   readw(ioaddr + ANLinkPartnerAbility),
+				   readl(ioaddr + IntrStatus));
+		if (readw(ioaddr + ANStatus) & 0x20)
+			writeb(0x01, ioaddr + LEDCtrl);
+		else
+			writeb(0x03, ioaddr + LEDCtrl);
+	}
+	if (intr_status & StatsMax) {
+		hamachi_get_stats(dev);
+		/* Read the overflow bits to clear. */
+		readl(ioaddr + 0x370);
+		readl(ioaddr + 0x3F0);
+	}
+	if ((intr_status & ~(LinkChange|StatsMax|NegotiationChange|IntrRxDone|IntrTxDone))
+		&& hamachi_debug)
+		printk(KERN_ERR "%s: Something Wicked happened! %4.4x.\n",
+			   dev->name, intr_status);
+	/* Hmmmmm, it's not clear how to recover from PCI faults. */
+	if (intr_status & (IntrTxPCIErr | IntrTxPCIFault))
+		hmp->stats.tx_fifo_errors++;
+	if (intr_status & (IntrRxPCIErr | IntrRxPCIFault))
+		hmp->stats.rx_fifo_errors++;
+}
+
+static int hamachi_close(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+	struct sk_buff *skb;
+	int i;
+
+	netif_stop_queue(dev);
+
+	if (hamachi_debug > 1) {
+		printk(KERN_DEBUG "%s: Shutting down ethercard, status was Tx %4.4x Rx %4.4x Int %2.2x.\n",
+			   dev->name, readw(ioaddr + TxStatus),
+			   readw(ioaddr + RxStatus), readl(ioaddr + IntrStatus));
+		printk(KERN_DEBUG "%s: Queue pointers were Tx %d / %d,  Rx %d / %d.\n",
+			   dev->name, hmp->cur_tx, hmp->dirty_tx, hmp->cur_rx, hmp->dirty_rx);
+	}
+
+	/* Disable interrupts by clearing the interrupt mask. */
+	writel(0x0000, ioaddr + InterruptEnable);
+
+	/* Stop the chip's Tx and Rx processes. */
+	writel(2, ioaddr + RxCmd);
+	writew(2, ioaddr + TxCmd);
+
+#ifdef __i386__
+	if (hamachi_debug > 2) {
+		printk("\n"KERN_DEBUG"  Tx ring at %8.8x:\n",
+			   (int)hmp->tx_ring_dma);
+		for (i = 0; i < TX_RING_SIZE; i++)
+			printk(" %c #%d desc. %8.8x %8.8x.\n",
+				   readl(ioaddr + TxCurPtr) == (long)&hmp->tx_ring[i] ? '>' : ' ',
+				   i, hmp->tx_ring[i].status_n_length, hmp->tx_ring[i].addr);
+		printk("\n"KERN_DEBUG "  Rx ring %8.8x:\n",
+			   (int)hmp->rx_ring_dma);
+		for (i = 0; i < RX_RING_SIZE; i++) {
+			printk(KERN_DEBUG " %c #%d desc. %4.4x %8.8x\n",
+				   readl(ioaddr + RxCurPtr) == (long)&hmp->rx_ring[i] ? '>' : ' ',
+				   i, hmp->rx_ring[i].status_n_length, hmp->rx_ring[i].addr);
+			if (hamachi_debug > 6) {
+				if (*(u8*)hmp->rx_skbuff[i]->tail != 0x69) {
+					u16 *addr = (u16 *)
+						hmp->rx_skbuff[i]->tail;
+					int j;
+
+					for (j = 0; j < 0x50; j++)
+						printk(" %4.4x", addr[j]);
+					printk("\n");
+				}
+			}
+		}
+	}
+#endif /* __i386__ debugging only */
+
+	free_irq(dev->irq, dev);
+
+	del_timer_sync(&hmp->timer);
+
+	/* Free all the skbuffs in the Rx queue. */
+	for (i = 0; i < RX_RING_SIZE; i++) {
+		skb = hmp->rx_skbuff[i];
+		hmp->rx_ring[i].status_n_length = 0;
+		hmp->rx_ring[i].addr = 0xBADF00D0; /* An invalid address. */
+		if (skb) {
+			pci_unmap_single(hmp->pci_dev, 
+				hmp->rx_ring[i].addr, hmp->rx_buf_sz, 
+				PCI_DMA_FROMDEVICE);
+			dev_kfree_skb(skb);
+			hmp->rx_skbuff[i] = NULL;
+		}
+	}
+	for (i = 0; i < TX_RING_SIZE; i++) {
+		skb = hmp->tx_skbuff[i];
+		if (skb) {
+			pci_unmap_single(hmp->pci_dev, 
+				hmp->tx_ring[i].addr, skb->len, 
+				PCI_DMA_TODEVICE);
+			dev_kfree_skb(skb);
+			hmp->tx_skbuff[i] = NULL;
+		}
+	}
+
+	writeb(0x00, ioaddr + LEDCtrl);
+
+	return 0;
+}
+
+static struct net_device_stats *hamachi_get_stats(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+
+	/* We should lock this segment of code for SMP eventually, although
+	   the vulnerability window is very small and statistics are
+	   non-critical. */
+        /* Ok, what goes here?  This appears to be stuck at 21 packets
+           according to ifconfig.  It does get incremented in hamachi_tx(),
+           so I think I'll comment it out here and see if better things
+           happen.
+        */ 
+	/* hmp->stats.tx_packets	= readl(ioaddr + 0x000); */
+
+	hmp->stats.rx_bytes = readl(ioaddr + 0x330); /* Total Uni+Brd+Multi */
+	hmp->stats.tx_bytes = readl(ioaddr + 0x3B0); /* Total Uni+Brd+Multi */
+	hmp->stats.multicast		= readl(ioaddr + 0x320); /* Multicast Rx */
+
+	hmp->stats.rx_length_errors	= readl(ioaddr + 0x368); /* Over+Undersized */
+	hmp->stats.rx_over_errors	= readl(ioaddr + 0x35C); /* Jabber */
+	hmp->stats.rx_crc_errors	= readl(ioaddr + 0x360); /* Jabber */
+	hmp->stats.rx_frame_errors	= readl(ioaddr + 0x364); /* Symbol Errs */
+	hmp->stats.rx_missed_errors	= readl(ioaddr + 0x36C); /* Dropped */
+
+	return &hmp->stats;
+}
+
+static void set_rx_mode(struct net_device *dev)
+{
+	struct hamachi_private *hmp = netdev_priv(dev);
+	void __iomem *ioaddr = hmp->base;
+
+	if (dev->flags & IFF_PROMISC) {			/* Set promiscuous. */
+		/* Unconditionally log net taps. */
+		printk(KERN_NOTICE "%s: Promiscuous mode enabled.\n", dev->name);
+		writew(0x000F, ioaddr + AddrMode);
+	} else if ((dev->mc_count > 63)  ||  (dev->flags & IFF_ALLMULTI)) {
+		/* Too many to match, or accept all multicasts. */
+		writew(0x000B, ioaddr + AddrMode);
+	} else if (dev->mc_count > 0) { /* Must use the CAM filter. */
+		struct dev_mc_list *mclist;
+		int i;
+		for (i = 0, mclist = dev->mc_list; mclist && i < dev->mc_count;
+			 i++, mclist = mclist->next) {
+			writel(*(u32*)(mclist->dmi_addr), ioaddr + 0x100 + i*8);
+			writel(0x20000 | (*(u16*)&mclist->dmi_addr[4]),
+				   ioaddr + 0x104 + i*8);
+		}
+		/* Clear remaining entries. */
+		for (; i < 64; i++)
+			writel(0, ioaddr + 0x104 + i*8);
+		writew(0x0003, ioaddr + AddrMode);
+	} else {					/* Normal, unicast/broadcast-only mode. */
+		writew(0x0001, ioaddr + AddrMode);
+	}
+}
+
+static int check_if_running(struct net_device *dev)
+{
+	if (!netif_running(dev))
+		return -EINVAL;
+	return 0;
+}
+
+static void hamachi_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	strcpy(info->driver, DRV_NAME);
+	strcpy(info->version, DRV_VERSION);
+	strcpy(info->bus_info, pci_name(np->pci_dev));
+}
+
+static int hamachi_get_settings(struct net_device *dev, struct ethtool_cmd *ecmd)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	spin_lock_irq(&np->lock);
+	mii_ethtool_gset(&np->mii_if, ecmd);
+	spin_unlock_irq(&np->lock);
+	return 0;
+}
+
+static int hamachi_set_settings(struct net_device *dev, struct ethtool_cmd *ecmd)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	int res;
+	spin_lock_irq(&np->lock);
+	res = mii_ethtool_sset(&np->mii_if, ecmd);
+	spin_unlock_irq(&np->lock);
+	return res;
+}
+
+static int hamachi_nway_reset(struct net_device *dev)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	return mii_nway_restart(&np->mii_if);
+}
+
+static u32 hamachi_get_link(struct net_device *dev)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	return mii_link_ok(&np->mii_if);
+}
+
+static struct ethtool_ops ethtool_ops = {
+	.begin = check_if_running,
+	.get_drvinfo = hamachi_get_drvinfo,
+	.get_settings = hamachi_get_settings,
+	.set_settings = hamachi_set_settings,
+	.nway_reset = hamachi_nway_reset,
+	.get_link = hamachi_get_link,
+};
+
+static struct ethtool_ops ethtool_ops_no_mii = {
+	.begin = check_if_running,
+	.get_drvinfo = hamachi_get_drvinfo,
+};
+
+static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+	struct hamachi_private *np = netdev_priv(dev);
+	struct mii_ioctl_data *data = if_mii(rq);
+	int rc;
+
+	if (!netif_running(dev))
+		return -EINVAL;
+
+	if (cmd == (SIOCDEVPRIVATE+3)) { /* set rx,tx intr params */
+		u32 *d = (u32 *)&rq->ifr_ifru;
+		/* Should add this check here or an ordinary user can do nasty
+		 * things. -KDU
+		 *
+		 * TODO: Shut down the Rx and Tx engines while doing this.
+		 */
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		writel(d[0], np->base + TxIntrCtrl);
+		writel(d[1], np->base + RxIntrCtrl);
+		printk(KERN_NOTICE "%s: tx %08x, rx %08x intr\n", dev->name,
+		  (u32) readl(np->base + TxIntrCtrl),
+		  (u32) readl(np->base + RxIntrCtrl));
+		rc = 0;
+	}
+
+	else {
+		spin_lock_irq(&np->lock);
+		rc = generic_mii_ioctl(&np->mii_if, data, cmd, NULL);
+		spin_unlock_irq(&np->lock);
+	}
+
+	return rc;
+}
+
+
+static void __devexit hamachi_remove_one (struct pci_dev *pdev)
+{
+	struct net_device *dev = pci_get_drvdata(pdev);
+
+	if (dev) {
+		struct hamachi_private *hmp = netdev_priv(dev);
+
+		pci_free_consistent(pdev, RX_TOTAL_SIZE, hmp->rx_ring, 
+			hmp->rx_ring_dma);
+		pci_free_consistent(pdev, TX_TOTAL_SIZE, hmp->tx_ring, 
+			hmp->tx_ring_dma);
+		unregister_netdev(dev);
+		iounmap(hmp->base);
+		free_netdev(dev);
+		pci_release_regions(pdev);
+		pci_set_drvdata(pdev, NULL);
+	}
+}
+
+static struct pci_device_id hamachi_pci_tbl[] = {
+	{ 0x1318, 0x0911, PCI_ANY_ID, PCI_ANY_ID, },
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, hamachi_pci_tbl);
+
+static struct pci_driver hamachi_driver = {
+	.name		= DRV_NAME,
+	.id_table	= hamachi_pci_tbl,
+	.probe		= hamachi_init_one,
+	.remove		= __devexit_p(hamachi_remove_one),
+};
+
+static int __init hamachi_init (void)
+{
+/* when a module, this is printed whether or not devices are found in probe */
+#ifdef MODULE
+	printk(version);
+#endif
+	return pci_register_driver(&hamachi_driver);
+}
+
+static void __exit hamachi_exit (void)
+{
+	pci_unregister_driver(&hamachi_driver);
+}
+
+
+module_init(hamachi_init);
+module_exit(hamachi_exit);