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3c527.c
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3c527.c
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/* 3c527.c: 3Com Etherlink/MC32 driver for Linux 2.4 and 2.6.
*
* (c) Copyright 1998 Red Hat Software Inc
* Written by Alan Cox.
* Further debugging by Carl Drougge.
* Initial SMP support by Felipe W Damasio <[email protected]>
* Heavily modified by Richard Procter <[email protected]>
*
* Based on skeleton.c written 1993-94 by Donald Becker and ne2.c
* (for the MCA stuff) written by Wim Dumon.
*
* Thanks to 3Com for making this possible by providing me with the
* documentation.
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
*/
#define DRV_NAME "3c527"
#define DRV_VERSION "0.7-SMP"
#define DRV_RELDATE "2003/09/21"
static const char *version =
DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " Richard Procter <[email protected]>\n";
/**
* DOC: Traps for the unwary
*
* The diagram (Figure 1-1) and the POS summary disagree with the
* "Interrupt Level" section in the manual.
*
* The manual contradicts itself when describing the minimum number
* buffers in the 'configure lists' command.
* My card accepts a buffer config of 4/4.
*
* Setting the SAV BP bit does not save bad packets, but
* only enables RX on-card stats collection.
*
* The documentation in places seems to miss things. In actual fact
* I've always eventually found everything is documented, it just
* requires careful study.
*
* DOC: Theory Of Operation
*
* The 3com 3c527 is a 32bit MCA bus mastering adapter with a large
* amount of on board intelligence that housekeeps a somewhat dumber
* Intel NIC. For performance we want to keep the transmit queue deep
* as the card can transmit packets while fetching others from main
* memory by bus master DMA. Transmission and reception are driven by
* circular buffer queues.
*
* The mailboxes can be used for controlling how the card traverses
* its buffer rings, but are used only for inital setup in this
* implementation. The exec mailbox allows a variety of commands to
* be executed. Each command must complete before the next is
* executed. Primarily we use the exec mailbox for controlling the
* multicast lists. We have to do a certain amount of interesting
* hoop jumping as the multicast list changes can occur in interrupt
* state when the card has an exec command pending. We defer such
* events until the command completion interrupt.
*
* A copy break scheme (taken from 3c59x.c) is employed whereby
* received frames exceeding a configurable length are passed
* directly to the higher networking layers without incuring a copy,
* in what amounts to a time/space trade-off.
*
* The card also keeps a large amount of statistical information
* on-board. In a perfect world, these could be used safely at no
* cost. However, lacking information to the contrary, processing
* them without races would involve so much extra complexity as to
* make it unworthwhile to do so. In the end, a hybrid SW/HW
* implementation was made necessary --- see mc32_update_stats().
*
* DOC: Notes
*
* It should be possible to use two or more cards, but at this stage
* only by loading two copies of the same module.
*
* The on-board 82586 NIC has trouble receiving multiple
* back-to-back frames and so is likely to drop packets from fast
* senders.
**/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/mca-legacy.h>
#include <linux/ioport.h>
#include <linux/in.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/ethtool.h>
#include <linux/completion.h>
#include <linux/bitops.h>
#include <linux/semaphore.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/dma.h>
#include "3c527.h"
MODULE_LICENSE("GPL");
/*
* The name of the card. Is used for messages and in the requests for
* io regions, irqs and dma channels
*/
static const char* cardname = DRV_NAME;
/* use 0 for production, 1 for verification, >2 for debug */
#ifndef NET_DEBUG
#define NET_DEBUG 2
#endif
static unsigned int mc32_debug = NET_DEBUG;
/* The number of low I/O ports used by the ethercard. */
#define MC32_IO_EXTENT 8
/* As implemented, values must be a power-of-2 -- 4/8/16/32 */
#define TX_RING_LEN 32 /* Typically the card supports 37 */
#define RX_RING_LEN 8 /* " " " */
/* Copy break point, see above for details.
* Setting to > 1512 effectively disables this feature. */
#define RX_COPYBREAK 200 /* Value from 3c59x.c */
/* Issue the 82586 workaround command - this is for "busy lans", but
* basically means for all lans now days - has a performance (latency)
* cost, but best set. */
static const int WORKAROUND_82586=1;
/* Pointers to buffers and their on-card records */
struct mc32_ring_desc
{
volatile struct skb_header *p;
struct sk_buff *skb;
};
/* Information that needs to be kept for each board. */
struct mc32_local
{
int slot;
u32 base;
volatile struct mc32_mailbox *rx_box;
volatile struct mc32_mailbox *tx_box;
volatile struct mc32_mailbox *exec_box;
volatile struct mc32_stats *stats; /* Start of on-card statistics */
u16 tx_chain; /* Transmit list start offset */
u16 rx_chain; /* Receive list start offset */
u16 tx_len; /* Transmit list count */
u16 rx_len; /* Receive list count */
u16 xceiver_desired_state; /* HALTED or RUNNING */
u16 cmd_nonblocking; /* Thread is uninterested in command result */
u16 mc_reload_wait; /* A multicast load request is pending */
u32 mc_list_valid; /* True when the mclist is set */
struct mc32_ring_desc tx_ring[TX_RING_LEN]; /* Host Transmit ring */
struct mc32_ring_desc rx_ring[RX_RING_LEN]; /* Host Receive ring */
atomic_t tx_count; /* buffers left */
atomic_t tx_ring_head; /* index to tx en-queue end */
u16 tx_ring_tail; /* index to tx de-queue end */
u16 rx_ring_tail; /* index to rx de-queue end */
struct semaphore cmd_mutex; /* Serialises issuing of execute commands */
struct completion execution_cmd; /* Card has completed an execute command */
struct completion xceiver_cmd; /* Card has completed a tx or rx command */
};
/* The station (ethernet) address prefix, used for a sanity check. */
#define SA_ADDR0 0x02
#define SA_ADDR1 0x60
#define SA_ADDR2 0xAC
struct mca_adapters_t {
unsigned int id;
char *name;
};
static const struct mca_adapters_t mc32_adapters[] = {
{ 0x0041, "3COM EtherLink MC/32" },
{ 0x8EF5, "IBM High Performance Lan Adapter" },
{ 0x0000, NULL }
};
/* Macros for ring index manipulations */
static inline u16 next_rx(u16 rx) { return (rx+1)&(RX_RING_LEN-1); };
static inline u16 prev_rx(u16 rx) { return (rx-1)&(RX_RING_LEN-1); };
static inline u16 next_tx(u16 tx) { return (tx+1)&(TX_RING_LEN-1); };
/* Index to functions, as function prototypes. */
static int mc32_probe1(struct net_device *dev, int ioaddr);
static int mc32_command(struct net_device *dev, u16 cmd, void *data, int len);
static int mc32_open(struct net_device *dev);
static void mc32_timeout(struct net_device *dev);
static netdev_tx_t mc32_send_packet(struct sk_buff *skb,
struct net_device *dev);
static irqreturn_t mc32_interrupt(int irq, void *dev_id);
static int mc32_close(struct net_device *dev);
static struct net_device_stats *mc32_get_stats(struct net_device *dev);
static void mc32_set_multicast_list(struct net_device *dev);
static void mc32_reset_multicast_list(struct net_device *dev);
static const struct ethtool_ops netdev_ethtool_ops;
static void cleanup_card(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
unsigned slot = lp->slot;
mca_mark_as_unused(slot);
mca_set_adapter_name(slot, NULL);
free_irq(dev->irq, dev);
release_region(dev->base_addr, MC32_IO_EXTENT);
}
/**
* mc32_probe - Search for supported boards
* @unit: interface number to use
*
* Because MCA bus is a real bus and we can scan for cards we could do a
* single scan for all boards here. Right now we use the passed in device
* structure and scan for only one board. This needs fixing for modules
* in particular.
*/
struct net_device *__init mc32_probe(int unit)
{
struct net_device *dev = alloc_etherdev(sizeof(struct mc32_local));
static int current_mca_slot = -1;
int i;
int err;
if (!dev)
return ERR_PTR(-ENOMEM);
if (unit >= 0)
sprintf(dev->name, "eth%d", unit);
/* Do not check any supplied i/o locations.
POS registers usually don't fail :) */
/* MCA cards have POS registers.
Autodetecting MCA cards is extremely simple.
Just search for the card. */
for(i = 0; (mc32_adapters[i].name != NULL); i++) {
current_mca_slot =
mca_find_unused_adapter(mc32_adapters[i].id, 0);
if(current_mca_slot != MCA_NOTFOUND) {
if(!mc32_probe1(dev, current_mca_slot))
{
mca_set_adapter_name(current_mca_slot,
mc32_adapters[i].name);
mca_mark_as_used(current_mca_slot);
err = register_netdev(dev);
if (err) {
cleanup_card(dev);
free_netdev(dev);
dev = ERR_PTR(err);
}
return dev;
}
}
}
free_netdev(dev);
return ERR_PTR(-ENODEV);
}
static const struct net_device_ops netdev_ops = {
.ndo_open = mc32_open,
.ndo_stop = mc32_close,
.ndo_start_xmit = mc32_send_packet,
.ndo_get_stats = mc32_get_stats,
.ndo_set_multicast_list = mc32_set_multicast_list,
.ndo_tx_timeout = mc32_timeout,
.ndo_change_mtu = eth_change_mtu,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
};
/**
* mc32_probe1 - Check a given slot for a board and test the card
* @dev: Device structure to fill in
* @slot: The MCA bus slot being used by this card
*
* Decode the slot data and configure the card structures. Having done this we
* can reset the card and configure it. The card does a full self test cycle
* in firmware so we have to wait for it to return and post us either a
* failure case or some addresses we use to find the board internals.
*/
static int __init mc32_probe1(struct net_device *dev, int slot)
{
static unsigned version_printed;
int i, err;
u8 POS;
u32 base;
struct mc32_local *lp = netdev_priv(dev);
static u16 mca_io_bases[]={
0x7280,0x7290,
0x7680,0x7690,
0x7A80,0x7A90,
0x7E80,0x7E90
};
static u32 mca_mem_bases[]={
0x00C0000,
0x00C4000,
0x00C8000,
0x00CC000,
0x00D0000,
0x00D4000,
0x00D8000,
0x00DC000
};
static char *failures[]={
"Processor instruction",
"Processor data bus",
"Processor data bus",
"Processor data bus",
"Adapter bus",
"ROM checksum",
"Base RAM",
"Extended RAM",
"82586 internal loopback",
"82586 initialisation failure",
"Adapter list configuration error"
};
/* Time to play MCA games */
if (mc32_debug && version_printed++ == 0)
pr_debug("%s", version);
pr_info("%s: %s found in slot %d: ", dev->name, cardname, slot);
POS = mca_read_stored_pos(slot, 2);
if(!(POS&1))
{
pr_cont("disabled.\n");
return -ENODEV;
}
/* Fill in the 'dev' fields. */
dev->base_addr = mca_io_bases[(POS>>1)&7];
dev->mem_start = mca_mem_bases[(POS>>4)&7];
POS = mca_read_stored_pos(slot, 4);
if(!(POS&1))
{
pr_cont("memory window disabled.\n");
return -ENODEV;
}
POS = mca_read_stored_pos(slot, 5);
i=(POS>>4)&3;
if(i==3)
{
pr_cont("invalid memory window.\n");
return -ENODEV;
}
i*=16384;
i+=16384;
dev->mem_end=dev->mem_start + i;
dev->irq = ((POS>>2)&3)+9;
if(!request_region(dev->base_addr, MC32_IO_EXTENT, cardname))
{
pr_cont("io 0x%3lX, which is busy.\n", dev->base_addr);
return -EBUSY;
}
pr_cont("io 0x%3lX irq %d mem 0x%lX (%dK)\n",
dev->base_addr, dev->irq, dev->mem_start, i/1024);
/* We ought to set the cache line size here.. */
/*
* Go PROM browsing
*/
/* Retrieve and print the ethernet address. */
for (i = 0; i < 6; i++)
{
mca_write_pos(slot, 6, i+12);
mca_write_pos(slot, 7, 0);
dev->dev_addr[i] = mca_read_pos(slot,3);
}
pr_info("%s: Address %pM ", dev->name, dev->dev_addr);
mca_write_pos(slot, 6, 0);
mca_write_pos(slot, 7, 0);
POS = mca_read_stored_pos(slot, 4);
if(POS&2)
pr_cont(": BNC port selected.\n");
else
pr_cont(": AUI port selected.\n");
POS=inb(dev->base_addr+HOST_CTRL);
POS|=HOST_CTRL_ATTN|HOST_CTRL_RESET;
POS&=~HOST_CTRL_INTE;
outb(POS, dev->base_addr+HOST_CTRL);
/* Reset adapter */
udelay(100);
/* Reset off */
POS&=~(HOST_CTRL_ATTN|HOST_CTRL_RESET);
outb(POS, dev->base_addr+HOST_CTRL);
udelay(300);
/*
* Grab the IRQ
*/
err = request_irq(dev->irq, &mc32_interrupt, IRQF_SHARED | IRQF_SAMPLE_RANDOM, DRV_NAME, dev);
if (err) {
release_region(dev->base_addr, MC32_IO_EXTENT);
pr_err("%s: unable to get IRQ %d.\n", DRV_NAME, dev->irq);
goto err_exit_ports;
}
memset(lp, 0, sizeof(struct mc32_local));
lp->slot = slot;
i=0;
base = inb(dev->base_addr);
while(base == 0xFF)
{
i++;
if(i == 1000)
{
pr_err("%s: failed to boot adapter.\n", dev->name);
err = -ENODEV;
goto err_exit_irq;
}
udelay(1000);
if(inb(dev->base_addr+2)&(1<<5))
base = inb(dev->base_addr);
}
if(base>0)
{
if(base < 0x0C)
pr_err("%s: %s%s.\n", dev->name, failures[base-1],
base<0x0A?" test failure":"");
else
pr_err("%s: unknown failure %d.\n", dev->name, base);
err = -ENODEV;
goto err_exit_irq;
}
base=0;
for(i=0;i<4;i++)
{
int n=0;
while(!(inb(dev->base_addr+2)&(1<<5)))
{
n++;
udelay(50);
if(n>100)
{
pr_err("%s: mailbox read fail (%d).\n", dev->name, i);
err = -ENODEV;
goto err_exit_irq;
}
}
base|=(inb(dev->base_addr)<<(8*i));
}
lp->exec_box=isa_bus_to_virt(dev->mem_start+base);
base=lp->exec_box->data[1]<<16|lp->exec_box->data[0];
lp->base = dev->mem_start+base;
lp->rx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[2]);
lp->tx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[3]);
lp->stats = isa_bus_to_virt(lp->base + lp->exec_box->data[5]);
/*
* Descriptor chains (card relative)
*/
lp->tx_chain = lp->exec_box->data[8]; /* Transmit list start offset */
lp->rx_chain = lp->exec_box->data[10]; /* Receive list start offset */
lp->tx_len = lp->exec_box->data[9]; /* Transmit list count */
lp->rx_len = lp->exec_box->data[11]; /* Receive list count */
init_MUTEX_LOCKED(&lp->cmd_mutex);
init_completion(&lp->execution_cmd);
init_completion(&lp->xceiver_cmd);
pr_info("%s: Firmware Rev %d. %d RX buffers, %d TX buffers. Base of 0x%08X.\n",
dev->name, lp->exec_box->data[12], lp->rx_len, lp->tx_len, lp->base);
dev->netdev_ops = &netdev_ops;
dev->watchdog_timeo = HZ*5; /* Board does all the work */
dev->ethtool_ops = &netdev_ethtool_ops;
return 0;
err_exit_irq:
free_irq(dev->irq, dev);
err_exit_ports:
release_region(dev->base_addr, MC32_IO_EXTENT);
return err;
}
/**
* mc32_ready_poll - wait until we can feed it a command
* @dev: The device to wait for
*
* Wait until the card becomes ready to accept a command via the
* command register. This tells us nothing about the completion
* status of any pending commands and takes very little time at all.
*/
static inline void mc32_ready_poll(struct net_device *dev)
{
int ioaddr = dev->base_addr;
while(!(inb(ioaddr+HOST_STATUS)&HOST_STATUS_CRR));
}
/**
* mc32_command_nowait - send a command non blocking
* @dev: The 3c527 to issue the command to
* @cmd: The command word to write to the mailbox
* @data: A data block if the command expects one
* @len: Length of the data block
*
* Send a command from interrupt state. If there is a command
* currently being executed then we return an error of -1. It
* simply isn't viable to wait around as commands may be
* slow. This can theoretically be starved on SMP, but it's hard
* to see a realistic situation. We do not wait for the command
* to complete --- we rely on the interrupt handler to tidy up
* after us.
*/
static int mc32_command_nowait(struct net_device *dev, u16 cmd, void *data, int len)
{
struct mc32_local *lp = netdev_priv(dev);
int ioaddr = dev->base_addr;
int ret = -1;
if (down_trylock(&lp->cmd_mutex) == 0)
{
lp->cmd_nonblocking=1;
lp->exec_box->mbox=0;
lp->exec_box->mbox=cmd;
memcpy((void *)lp->exec_box->data, data, len);
barrier(); /* the memcpy forgot the volatile so be sure */
/* Send the command */
mc32_ready_poll(dev);
outb(1<<6, ioaddr+HOST_CMD);
ret = 0;
/* Interrupt handler will signal mutex on completion */
}
return ret;
}
/**
* mc32_command - send a command and sleep until completion
* @dev: The 3c527 card to issue the command to
* @cmd: The command word to write to the mailbox
* @data: A data block if the command expects one
* @len: Length of the data block
*
* Sends exec commands in a user context. This permits us to wait around
* for the replies and also to wait for the command buffer to complete
* from a previous command before we execute our command. After our
* command completes we will attempt any pending multicast reload
* we blocked off by hogging the exec buffer.
*
* You feed the card a command, you wait, it interrupts you get a
* reply. All well and good. The complication arises because you use
* commands for filter list changes which come in at bh level from things
* like IPV6 group stuff.
*/
static int mc32_command(struct net_device *dev, u16 cmd, void *data, int len)
{
struct mc32_local *lp = netdev_priv(dev);
int ioaddr = dev->base_addr;
int ret = 0;
down(&lp->cmd_mutex);
/*
* My Turn
*/
lp->cmd_nonblocking=0;
lp->exec_box->mbox=0;
lp->exec_box->mbox=cmd;
memcpy((void *)lp->exec_box->data, data, len);
barrier(); /* the memcpy forgot the volatile so be sure */
mc32_ready_poll(dev);
outb(1<<6, ioaddr+HOST_CMD);
wait_for_completion(&lp->execution_cmd);
if(lp->exec_box->mbox&(1<<13))
ret = -1;
up(&lp->cmd_mutex);
/*
* A multicast set got blocked - try it now
*/
if(lp->mc_reload_wait)
{
mc32_reset_multicast_list(dev);
}
return ret;
}
/**
* mc32_start_transceiver - tell board to restart tx/rx
* @dev: The 3c527 card to issue the command to
*
* This may be called from the interrupt state, where it is used
* to restart the rx ring if the card runs out of rx buffers.
*
* We must first check if it's ok to (re)start the transceiver. See
* mc32_close for details.
*/
static void mc32_start_transceiver(struct net_device *dev) {
struct mc32_local *lp = netdev_priv(dev);
int ioaddr = dev->base_addr;
/* Ignore RX overflow on device closure */
if (lp->xceiver_desired_state==HALTED)
return;
/* Give the card the offset to the post-EOL-bit RX descriptor */
mc32_ready_poll(dev);
lp->rx_box->mbox=0;
lp->rx_box->data[0]=lp->rx_ring[prev_rx(lp->rx_ring_tail)].p->next;
outb(HOST_CMD_START_RX, ioaddr+HOST_CMD);
mc32_ready_poll(dev);
lp->tx_box->mbox=0;
outb(HOST_CMD_RESTRT_TX, ioaddr+HOST_CMD); /* card ignores this on RX restart */
/* We are not interrupted on start completion */
}
/**
* mc32_halt_transceiver - tell board to stop tx/rx
* @dev: The 3c527 card to issue the command to
*
* We issue the commands to halt the card's transceiver. In fact,
* after some experimenting we now simply tell the card to
* suspend. When issuing aborts occasionally odd things happened.
*
* We then sleep until the card has notified us that both rx and
* tx have been suspended.
*/
static void mc32_halt_transceiver(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
int ioaddr = dev->base_addr;
mc32_ready_poll(dev);
lp->rx_box->mbox=0;
outb(HOST_CMD_SUSPND_RX, ioaddr+HOST_CMD);
wait_for_completion(&lp->xceiver_cmd);
mc32_ready_poll(dev);
lp->tx_box->mbox=0;
outb(HOST_CMD_SUSPND_TX, ioaddr+HOST_CMD);
wait_for_completion(&lp->xceiver_cmd);
}
/**
* mc32_load_rx_ring - load the ring of receive buffers
* @dev: 3c527 to build the ring for
*
* This initalises the on-card and driver datastructures to
* the point where mc32_start_transceiver() can be called.
*
* The card sets up the receive ring for us. We are required to use the
* ring it provides, although the size of the ring is configurable.
*
* We allocate an sk_buff for each ring entry in turn and
* initalise its house-keeping info. At the same time, we read
* each 'next' pointer in our rx_ring array. This reduces slow
* shared-memory reads and makes it easy to access predecessor
* descriptors.
*
* We then set the end-of-list bit for the last entry so that the
* card will know when it has run out of buffers.
*/
static int mc32_load_rx_ring(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
int i;
u16 rx_base;
volatile struct skb_header *p;
rx_base=lp->rx_chain;
for(i=0; i<RX_RING_LEN; i++) {
lp->rx_ring[i].skb=alloc_skb(1532, GFP_KERNEL);
if (lp->rx_ring[i].skb==NULL) {
for (;i>=0;i--)
kfree_skb(lp->rx_ring[i].skb);
return -ENOBUFS;
}
skb_reserve(lp->rx_ring[i].skb, 18);
p=isa_bus_to_virt(lp->base+rx_base);
p->control=0;
p->data=isa_virt_to_bus(lp->rx_ring[i].skb->data);
p->status=0;
p->length=1532;
lp->rx_ring[i].p=p;
rx_base=p->next;
}
lp->rx_ring[i-1].p->control |= CONTROL_EOL;
lp->rx_ring_tail=0;
return 0;
}
/**
* mc32_flush_rx_ring - free the ring of receive buffers
* @lp: Local data of 3c527 to flush the rx ring of
*
* Free the buffer for each ring slot. This may be called
* before mc32_load_rx_ring(), eg. on error in mc32_open().
* Requires rx skb pointers to point to a valid skb, or NULL.
*/
static void mc32_flush_rx_ring(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
int i;
for(i=0; i < RX_RING_LEN; i++)
{
if (lp->rx_ring[i].skb) {
dev_kfree_skb(lp->rx_ring[i].skb);
lp->rx_ring[i].skb = NULL;
}
lp->rx_ring[i].p=NULL;
}
}
/**
* mc32_load_tx_ring - load transmit ring
* @dev: The 3c527 card to issue the command to
*
* This sets up the host transmit data-structures.
*
* First, we obtain from the card it's current postion in the tx
* ring, so that we will know where to begin transmitting
* packets.
*
* Then, we read the 'next' pointers from the on-card tx ring into
* our tx_ring array to reduce slow shared-mem reads. Finally, we
* intitalise the tx house keeping variables.
*
*/
static void mc32_load_tx_ring(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
volatile struct skb_header *p;
int i;
u16 tx_base;
tx_base=lp->tx_box->data[0];
for(i=0 ; i<TX_RING_LEN ; i++)
{
p=isa_bus_to_virt(lp->base+tx_base);
lp->tx_ring[i].p=p;
lp->tx_ring[i].skb=NULL;
tx_base=p->next;
}
/* -1 so that tx_ring_head cannot "lap" tx_ring_tail */
/* see mc32_tx_ring */
atomic_set(&lp->tx_count, TX_RING_LEN-1);
atomic_set(&lp->tx_ring_head, 0);
lp->tx_ring_tail=0;
}
/**
* mc32_flush_tx_ring - free transmit ring
* @lp: Local data of 3c527 to flush the tx ring of
*
* If the ring is non-empty, zip over the it, freeing any
* allocated skb_buffs. The tx ring house-keeping variables are
* then reset. Requires rx skb pointers to point to a valid skb,
* or NULL.
*/
static void mc32_flush_tx_ring(struct net_device *dev)
{
struct mc32_local *lp = netdev_priv(dev);
int i;
for (i=0; i < TX_RING_LEN; i++)
{
if (lp->tx_ring[i].skb)
{
dev_kfree_skb(lp->tx_ring[i].skb);
lp->tx_ring[i].skb = NULL;
}
}
atomic_set(&lp->tx_count, 0);
atomic_set(&lp->tx_ring_head, 0);
lp->tx_ring_tail=0;
}
/**
* mc32_open - handle 'up' of card
* @dev: device to open
*
* The user is trying to bring the card into ready state. This requires
* a brief dialogue with the card. Firstly we enable interrupts and then
* 'indications'. Without these enabled the card doesn't bother telling
* us what it has done. This had me puzzled for a week.
*
* We configure the number of card descriptors, then load the network
* address and multicast filters. Turn on the workaround mode. This
* works around a bug in the 82586 - it asks the firmware to do
* so. It has a performance (latency) hit but is needed on busy
* [read most] lans. We load the ring with buffers then we kick it
* all off.
*/
static int mc32_open(struct net_device *dev)
{
int ioaddr = dev->base_addr;
struct mc32_local *lp = netdev_priv(dev);
u8 one=1;
u8 regs;
u16 descnumbuffs[2] = {TX_RING_LEN, RX_RING_LEN};
/*
* Interrupts enabled
*/
regs=inb(ioaddr+HOST_CTRL);
regs|=HOST_CTRL_INTE;
outb(regs, ioaddr+HOST_CTRL);
/*
* Allow ourselves to issue commands
*/
up(&lp->cmd_mutex);
/*
* Send the indications on command
*/
mc32_command(dev, 4, &one, 2);
/*
* Poke it to make sure it's really dead.
*/
mc32_halt_transceiver(dev);
mc32_flush_tx_ring(dev);
/*
* Ask card to set up on-card descriptors to our spec
*/
if(mc32_command(dev, 8, descnumbuffs, 4)) {
pr_info("%s: %s rejected our buffer configuration!\n",
dev->name, cardname);
mc32_close(dev);
return -ENOBUFS;
}
/* Report new configuration */
mc32_command(dev, 6, NULL, 0);
lp->tx_chain = lp->exec_box->data[8]; /* Transmit list start offset */
lp->rx_chain = lp->exec_box->data[10]; /* Receive list start offset */
lp->tx_len = lp->exec_box->data[9]; /* Transmit list count */
lp->rx_len = lp->exec_box->data[11]; /* Receive list count */
/* Set Network Address */
mc32_command(dev, 1, dev->dev_addr, 6);
/* Set the filters */
mc32_set_multicast_list(dev);
if (WORKAROUND_82586) {
u16 zero_word=0;
mc32_command(dev, 0x0D, &zero_word, 2); /* 82586 bug workaround on */
}
mc32_load_tx_ring(dev);
if(mc32_load_rx_ring(dev))
{
mc32_close(dev);
return -ENOBUFS;
}
lp->xceiver_desired_state = RUNNING;
/* And finally, set the ball rolling... */
mc32_start_transceiver(dev);
netif_start_queue(dev);
return 0;
}
/**
* mc32_timeout - handle a timeout from the network layer
* @dev: 3c527 that timed out
*
* Handle a timeout on transmit from the 3c527. This normally means
* bad things as the hardware handles cable timeouts and mess for
* us.
*
*/
static void mc32_timeout(struct net_device *dev)
{
pr_warning("%s: transmit timed out?\n", dev->name);
/* Try to restart the adaptor. */
netif_wake_queue(dev);
}