硬件平台：FL2440 （S3C2440）
内核版本：2.6.35
主机平台：Ubuntu 11.04
内核版本：2.6.39
交叉编译器：arm-linux-gcc 4.3.2
原创作品，转载请标明出处http://blog.csdn.net/yming0221/article/details/6628624
本文接上文
1、接下来接着分析DM9000网卡驱动的数据接收函数
/* * Received a packet and pass to upper layer2、下面是完整的DM9000驱动代码，可以完整的查看
* 接收数据包，将数据包传递给上层
*/
static void
dm9000_rx(struct net_device *dev)
{
board_info_t *db = netdev_priv(dev);/* 得到网卡私有信息数据结构的首地址 */
struct dm9000_rxhdr rxhdr;/* 该结构体封装了dm9000接收的数据包信息 */
struct sk_buff *skb;
u8 rxbyte, *rdptr;
bool GoodPacket;
int RxLen;
/* Check packet ready or not */
do {
/* MRCMDX是内存数据预取读命令 */
ior(db, DM9000_MRCMDX);/* Dummy read */
/* Get most updated data */
rxbyte = readb(db->io_data);
/* Status check: this byte must be 0 or 1 */
/* DM9000_PKT_ERR 0x02 ,表示接收出错 */
if (rxbyte & DM9000_PKT_ERR) {
dev_warn(db->dev, "status check fail: %d\n", rxbyte);/* 输出提示信息 */
iow(db, DM9000_RCR, 0x00);/* Stop Device 关闭设备 */
iow(db, DM9000_ISR, IMR_PAR);/* Stop INT request 停止中断请求*/
return;
}
/* DM9000_PKT_RDY 0x01 没有准备好，直接返回*/
if (!(rxbyte & DM9000_PKT_RDY))
return;
/* A packet ready now & Get status/length */
GoodPacket = true;
writeb(DM9000_MRCMD, db->io_addr);/* MRCMD是地址增加的数据读取命令 */
(db->inblk)(db->io_data, &rxhdr, sizeof(rxhdr));/* 读取数据，从RX_SRAM到 rxhdr结构体中*/
RxLen = le16_to_cpu(rxhdr.RxLen);
if (netif_msg_rx_status(db))
dev_dbg(db->dev, "RX: status %02x, length %04x\n",
rxhdr.RxStatus, RxLen);
/* Packet Status check ，检查包的完整性*/
if (RxLen < 0x40) {
GoodPacket = false;
if (netif_msg_rx_err(db))
dev_dbg(db->dev, "RX: Bad Packet (runt)\n");
}
/* 如果数据长度大于DM9000_PKT_MAX ，即 1536 */
if (RxLen > DM9000_PKT_MAX) {
dev_dbg(db->dev, "RST: RX Len:%x\n", RxLen);
}
/* rxhdr.RxStatus is identical to RSR register. */
/* 这里也是包的检查 */
if (rxhdr.RxStatus & (RSR_FOE | RSR_CE | RSR_AE |
RSR_PLE | RSR_RWTO |
RSR_LCS | RSR_RF)) {
GoodPacket = false;
if (rxhdr.RxStatus & RSR_FOE) {
if (netif_msg_rx_err(db))
dev_dbg(db->dev, "fifo error\n");
dev->stats.rx_fifo_errors++;
}
if (rxhdr.RxStatus & RSR_CE) {
if (netif_msg_rx_err(db))
dev_dbg(db->dev, "crc error\n");
dev->stats.rx_crc_errors++;
}
if (rxhdr.RxStatus & RSR_RF) {
if (netif_msg_rx_err(db))
dev_dbg(db->dev, "length error\n");
dev->stats.rx_length_errors++;
}
}
/* Move data from DM9000 ，从DM9000获取数据*/
if (GoodPacket &&
((skb = dev_alloc_skb(RxLen + 4)) != NULL)) {
skb_reserve(skb, 2);
rdptr = (u8 *) skb_put(skb, RxLen - 4);
/* Read received packet from RX SRAM */
/* 将RX SRAM中的数据读取到skbuff结构体 */
(db->inblk)(db->io_data, rdptr, RxLen);
dev->stats.rx_bytes += RxLen;
/* Pass to upper layer */
skb->protocol = eth_type_trans(skb, dev);
if (db->rx_csum) {
if ((((rxbyte & 0x1c) << 3) & rxbyte) == 0)
skb->ip_summed = CHECKSUM_UNNECESSARY;
else
skb->ip_summed = CHECKSUM_NONE;
}
netif_rx(skb);/* 将skbuff结构体发送给上层 */
dev->stats.rx_packets++;/* 计数增1 */
} else {
/* need to dump the packet's data */
/* 坏包，丢弃 */
(db->dumpblk)(db->io_data, RxLen);
}
} while (rxbyte & DM9000_PKT_RDY);
}
#include <linux/module.h>#include <linux/ioport.h>#include <linux/netdevice.h>#include <linux/etherdevice.h>#include <linux/init.h>#include <linux/skbuff.h>#include <linux/spinlock.h>#include <linux/crc32.h>#include <linux/mii.h>#include <linux/ethtool.h>#include <linux/dm9000.h>#include <linux/delay.h>#include <linux/platform_device.h>#include <linux/irq.h>#include <linux/slab.h>#include <asm/delay.h>#include <asm/irq.h>#include <asm/io.h>#include "dm9000.h"#include <mach/regs-gpio.h> #include <mach/irqs.h>#include <mach/hardware.h>/* Board/System/Debug information/definition ---------------- */#define DM9000_PHY0x40/* PHY address 0x01 */#define CARDNAME"dm9000"#define DRV_VERSION"1.31"/* * Transmit timeout, default 5 seconds. */static int watchdog = 5000;module_param(watchdog, int, 0400);MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");/* DM9000 register address locking. * * The DM9000 uses an address register to control where data written * to the data register goes. This means that the address register * must be preserved over interrupts or similar calls. * * During interrupt and other critical calls, a spinlock is used to * protect the system, but the calls themselves save the address * in the address register in case they are interrupting another * access to the device. * * For general accesses a lock is provided so that calls which are * allowed to sleep are serialised so that the address register does * not need to be saved. This lock also serves to serialise access * to the EEPROM and PHY access registers which are shared between * these two devices. *//* The driver supports the original DM9000E, and now the two newer * devices, DM9000A and DM9000B. */enum dm9000_type {TYPE_DM9000E,/* original DM9000 */TYPE_DM9000A,TYPE_DM9000B};/* Structure/enum declaration ------------------------------- */typedef struct board_info {void __iomem*io_addr;/* Register I/O base address */void __iomem*io_data;/* Data I/O address */u16 irq;/* IRQ */u16tx_pkt_cnt;u16queue_pkt_len;u16queue_start_addr;u16queue_ip_summed;u16dbug_cnt;u8io_mode;/* 0:word, 2:byte */u8phy_addr;u8imr_all;unsigned intflags;unsigned intin_suspend :1;unsigned intwake_supported :1;intdebug_level;enum dm9000_type type;void (*inblk)(void __iomem *port, void *data, int length);void (*outblk)(void __iomem *port, void *data, int length);void (*dumpblk)(void __iomem *port, int length);struct device*dev; /* parent device */struct resource*addr_res; /* resources found */struct resource *data_res;struct resource*addr_req; /* resources requested */struct resource *data_req;struct resource *irq_res;int irq_wake;struct mutex addr_lock;/* phy and eeprom access lock */struct delayed_work phy_poll;struct net_device *ndev;spinlock_tlock;struct mii_if_info mii;u32msg_enable;u32wake_state;intrx_csum;intcan_csum;intip_summed;} board_info_t;/* debug code */#define dm9000_dbg(db, lev, msg...) do {\if ((lev) < CONFIG_DM9000_DEBUGLEVEL &&\ (lev) < db->debug_level) {\dev_dbg(db->dev, msg);\}\} while (0)static inline board_info_t *to_dm9000_board(struct net_device *dev){return netdev_priv(dev);}/* DM9000 network board routine ---------------------------- */static voiddm9000_reset(board_info_t * db){dev_dbg(db->dev, "resetting device\n");/* RESET device */writeb(DM9000_NCR, db->io_addr);udelay(200);writeb(NCR_RST, db->io_data);udelay(200);}/* * Read a byte from I/O port */static u8ior(board_info_t * db, int reg){writeb(reg, db->io_addr);return readb(db->io_data);}/* * Write a byte to I/O port */static voidiow(board_info_t * db, int reg, int value){writeb(reg, db->io_addr);writeb(value, db->io_data);}/* routines for sending block to chip */static void dm9000_outblk_8bit(void __iomem *reg, void *data, int count){writesb(reg, data, count);}static void dm9000_outblk_16bit(void __iomem *reg, void *data, int count){writesw(reg, data, (count+1) >> 1);}static void dm9000_outblk_32bit(void __iomem *reg, void *data, int count){writesl(reg, data, (count+3) >> 2);}/* input block from chip to memory */static void dm9000_inblk_8bit(void __iomem *reg, void *data, int count){readsb(reg, data, count);}static void dm9000_inblk_16bit(void __iomem *reg, void *data, int count){readsw(reg, data, (count+1) >> 1);}static void dm9000_inblk_32bit(void __iomem *reg, void *data, int count){readsl(reg, data, (count+3) >> 2);}/* dump block from chip to null */static void dm9000_dumpblk_8bit(void __iomem *reg, int count){int i;int tmp;for (i = 0; i < count; i++)tmp = readb(reg);}static void dm9000_dumpblk_16bit(void __iomem *reg, int count){int i;int tmp;count = (count + 1) >> 1;for (i = 0; i < count; i++)tmp = readw(reg);}static void dm9000_dumpblk_32bit(void __iomem *reg, int count){int i;int tmp;count = (count + 3) >> 2;for (i = 0; i < count; i++)tmp = readl(reg);}/* dm9000_set_io * * select the specified set of io routines to use with the * device */static void dm9000_set_io(struct board_info *db, int byte_width){/* use the size of the data resource to work out what IO * routines we want to use */switch (byte_width) {case 1:db->dumpblk = dm9000_dumpblk_8bit;db->outblk = dm9000_outblk_8bit;db->inblk = dm9000_inblk_8bit;break;case 3:dev_dbg(db->dev, ": 3 byte IO, falling back to 16bit\n");case 2:db->dumpblk = dm9000_dumpblk_16bit;db->outblk = dm9000_outblk_16bit;db->inblk = dm9000_inblk_16bit;break;case 4:default:db->dumpblk = dm9000_dumpblk_32bit;db->outblk = dm9000_outblk_32bit;db->inblk = dm9000_inblk_32bit;break;}}static void dm9000_schedule_poll(board_info_t *db){if (db->type == TYPE_DM9000E)schedule_delayed_work(&db->phy_poll, HZ * 2);}static int dm9000_ioctl(struct net_device *dev, struct ifreq *req, int cmd){board_info_t *dm = to_dm9000_board(dev);if (!netif_running(dev))return -EINVAL;return generic_mii_ioctl(&dm->mii, if_mii(req), cmd, NULL);}static unsigned intdm9000_read_locked(board_info_t *db, int reg){unsigned long flags;unsigned int ret;spin_lock_irqsave(&db->lock, flags);ret = ior(db, reg);spin_unlock_irqrestore(&db->lock, flags);return ret;}static int dm9000_wait_eeprom(board_info_t *db){unsigned int status;int timeout = 8;/* wait max 8msec *//* The DM9000 data sheets say we should be able to * poll the ERRE bit in EPCR to wait for the EEPROM * operation. From testing several chips, this bit * does not seem to work. * * We attempt to use the bit, but fall back to the * timeout (which is why we do not return an error * on expiry) to say that the EEPROM operation has * completed. */while (1) {status = dm9000_read_locked(db, DM9000_EPCR);if ((status & EPCR_ERRE) == 0)break;msleep(1);if (timeout-- < 0) {dev_dbg(db->dev, "timeout waiting EEPROM\n");break;}}return 0;}/* * Read a word data from EEPROM */static voiddm9000_read_eeprom(board_info_t *db, int offset, u8 *to){unsigned long flags;if (db->flags & DM9000_PLATF_NO_EEPROM) {to[0] = 0xff;to[1] = 0xff;return;}mutex_lock(&db->addr_lock);spin_lock_irqsave(&db->lock, flags);iow(db, DM9000_EPAR, offset);iow(db, DM9000_EPCR, EPCR_ERPRR);spin_unlock_irqrestore(&db->lock, flags);dm9000_wait_eeprom(db);/* delay for at-least 150uS */msleep(1);spin_lock_irqsave(&db->lock, flags);iow(db, DM9000_EPCR, 0x0);to[0] = ior(db, DM9000_EPDRL);to[1] = ior(db, DM9000_EPDRH);spin_unlock_irqrestore(&db->lock, flags);mutex_unlock(&db->addr_lock);}/* * Write a word data to SROM */static voiddm9000_write_eeprom(board_info_t *db, int offset, u8 *data){unsigned long flags;if (db->flags & DM9000_PLATF_NO_EEPROM)return;mutex_lock(&db->addr_lock);spin_lock_irqsave(&db->lock, flags);iow(db, DM9000_EPAR, offset);iow(db, DM9000_EPDRH, data[1]);iow(db, DM9000_EPDRL, data[0]);iow(db, DM9000_EPCR, EPCR_WEP | EPCR_ERPRW);spin_unlock_irqrestore(&db->lock, flags);dm9000_wait_eeprom(db);mdelay(1);/* wait at least 150uS to clear */spin_lock_irqsave(&db->lock, flags);iow(db, DM9000_EPCR, 0);spin_unlock_irqrestore(&db->lock, flags);mutex_unlock(&db->addr_lock);}/* ethtool ops */static void dm9000_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info){board_info_t *dm = to_dm9000_board(dev);strcpy(info->driver, CARDNAME);strcpy(info->version, DRV_VERSION);strcpy(info->bus_info, to_platform_device(dm->dev)->name);}static u32 dm9000_get_msglevel(struct net_device *dev){board_info_t *dm = to_dm9000_board(dev);return dm->msg_enable;}static void dm9000_set_msglevel(struct net_device *dev, u32 value){board_info_t *dm = to_dm9000_board(dev);dm->msg_enable = value;}static int dm9000_get_settings(struct net_device *dev, struct ethtool_cmd *cmd){board_info_t *dm = to_dm9000_board(dev);mii_ethtool_gset(&dm->mii, cmd);return 0;}static int dm9000_set_settings(struct net_device *dev, struct ethtool_cmd *cmd){board_info_t *dm = to_dm9000_board(dev);return mii_ethtool_sset(&dm->mii, cmd);}static int dm9000_nway_reset(struct net_device *dev){board_info_t *dm = to_dm9000_board(dev);return mii_nway_restart(&dm->mii);}static uint32_t dm9000_get_rx_csum(struct net_device *dev){board_info_t *dm = to_dm9000_board(dev);return dm->rx_csum;}static int dm9000_set_rx_csum_unlocked(struct net_device *dev, uint32_t data){board_info_t *dm = to_dm9000_board(dev);if (dm->can_csum) {dm->rx_csum = data;iow(dm, DM9000_RCSR, dm->rx_csum ? RCSR_CSUM : 0);return 0;}return -EOPNOTSUPP;}static int dm9000_set_rx_csum(struct net_device *dev, uint32_t data){board_info_t *dm = to_dm9000_board(dev);unsigned long flags;int ret;spin_lock_irqsave(&dm->lock, flags);ret = dm9000_set_rx_csum_unlocked(dev, data);spin_unlock_irqrestore(&dm->lock, flags);return ret;}static int dm9000_set_tx_csum(struct net_device *dev, uint32_t data){board_info_t *dm = to_dm9000_board(dev);int ret = -EOPNOTSUPP;if (dm->can_csum)ret = ethtool_op_set_tx_csum(dev, data);return ret;}static u32 dm9000_get_link(struct net_device *dev){board_info_t *dm = to_dm9000_board(dev);u32 ret;if (dm->flags & DM9000_PLATF_EXT_PHY)ret = mii_link_ok(&dm->mii);elseret = dm9000_read_locked(dm, DM9000_NSR) & NSR_LINKST ? 1 : 0;return ret;}#define DM_EEPROM_MAGIC(0x444D394B)static int dm9000_get_eeprom_len(struct net_device *dev){return 128;}static int dm9000_get_eeprom(struct net_device *dev, struct ethtool_eeprom *ee, u8 *data){board_info_t *dm = to_dm9000_board(dev);int offset = ee->offset;int len = ee->len;int i;/* EEPROM access is aligned to two bytes */if ((len & 1) != 0 || (offset & 1) != 0)return -EINVAL;if (dm->flags & DM9000_PLATF_NO_EEPROM)return -ENOENT;ee->magic = DM_EEPROM_MAGIC;for (i = 0; i < len; i += 2)dm9000_read_eeprom(dm, (offset + i) / 2, data + i);return 0;}static int dm9000_set_eeprom(struct net_device *dev, struct ethtool_eeprom *ee, u8 *data){board_info_t *dm = to_dm9000_board(dev);int offset = ee->offset;int len = ee->len;int i;/* EEPROM access is aligned to two bytes */if ((len & 1) != 0 || (offset & 1) != 0)return -EINVAL;if (dm->flags & DM9000_PLATF_NO_EEPROM)return -ENOENT;if (ee->magic != DM_EEPROM_MAGIC)return -EINVAL;for (i = 0; i < len; i += 2)dm9000_write_eeprom(dm, (offset + i) / 2, data + i);return 0;}static void dm9000_get_wol(struct net_device *dev, struct ethtool_wolinfo *w){board_info_t *dm = to_dm9000_board(dev);memset(w, 0, sizeof(struct ethtool_wolinfo));/* note, we could probably support wake-phy too */w->supported = dm->wake_supported ? WAKE_MAGIC : 0;w->wolopts = dm->wake_state;}static int dm9000_set_wol(struct net_device *dev, struct ethtool_wolinfo *w){board_info_t *dm = to_dm9000_board(dev);unsigned long flags;u32 opts = w->wolopts;u32 wcr = 0;if (!dm->wake_supported)return -EOPNOTSUPP;if (opts & ~WAKE_MAGIC)return -EINVAL;if (opts & WAKE_MAGIC)wcr |= WCR_MAGICEN;mutex_lock(&dm->addr_lock);spin_lock_irqsave(&dm->lock, flags);iow(dm, DM9000_WCR, wcr);spin_unlock_irqrestore(&dm->lock, flags);mutex_unlock(&dm->addr_lock);if (dm->wake_state != opts) {/* change in wol state, update IRQ state */if (!dm->wake_state)set_irq_wake(dm->irq_wake, 1);else if (dm->wake_state & !opts)set_irq_wake(dm->irq_wake, 0);}dm->wake_state = opts;return 0;}static const struct ethtool_ops dm9000_ethtool_ops = {.get_drvinfo= dm9000_get_drvinfo,.get_settings= dm9000_get_settings,.set_settings= dm9000_set_settings,.get_msglevel= dm9000_get_msglevel,.set_msglevel= dm9000_set_msglevel,.nway_reset= dm9000_nway_reset,.get_link= dm9000_get_link,.get_wol= dm9000_get_wol,.set_wol= dm9000_set_wol, .get_eeprom_len= dm9000_get_eeprom_len, .get_eeprom= dm9000_get_eeprom, .set_eeprom= dm9000_set_eeprom,.get_rx_csum= dm9000_get_rx_csum,.set_rx_csum= dm9000_set_rx_csum,.get_tx_csum= ethtool_op_get_tx_csum,.set_tx_csum= dm9000_set_tx_csum,};static void dm9000_show_carrier(board_info_t *db,unsigned carrier, unsigned nsr){struct net_device *ndev = db->ndev;unsigned ncr = dm9000_read_locked(db, DM9000_NCR);if (carrier)dev_info(db->dev, "%s: link up, %dMbps, %s-duplex, no LPA\n", ndev->name, (nsr & NSR_SPEED) ? 10 : 100, (ncr & NCR_FDX) ? "full" : "half");elsedev_info(db->dev, "%s: link down\n", ndev->name);}static voiddm9000_poll_work(struct work_struct *w){struct delayed_work *dw = to_delayed_work(w);board_info_t *db = container_of(dw, board_info_t, phy_poll);struct net_device *ndev = db->ndev;if (db->flags & DM9000_PLATF_SIMPLE_PHY && !(db->flags & DM9000_PLATF_EXT_PHY)) {unsigned nsr = dm9000_read_locked(db, DM9000_NSR);unsigned old_carrier = netif_carrier_ok(ndev) ? 1 : 0;unsigned new_carrier;new_carrier = (nsr & NSR_LINKST) ? 1 : 0;if (old_carrier != new_carrier) {if (netif_msg_link(db))dm9000_show_carrier(db, new_carrier, nsr);if (!new_carrier)netif_carrier_off(ndev);elsenetif_carrier_on(ndev);}} elsemii_check_media(&db->mii, netif_msg_link(db), 0);if (netif_running(ndev))dm9000_schedule_poll(db);}/* dm9000_release_board * * release a board, and any mapped resources */static voiddm9000_release_board(struct platform_device *pdev, struct board_info *db){/* unmap our resources */iounmap(db->io_addr);iounmap(db->io_data);/* release the resources */release_resource(db->data_req);kfree(db->data_req);release_resource(db->addr_req);kfree(db->addr_req);}static unsigned char dm9000_type_to_char(enum dm9000_type type){switch (type) {case TYPE_DM9000E: return 'e';case TYPE_DM9000A: return 'a';case TYPE_DM9000B: return 'b';}return '?';}/* * Set DM9000 multicast address */static voiddm9000_hash_table_unlocked(struct net_device *dev){board_info_t *db = netdev_priv(dev);struct netdev_hw_addr *ha;int i, oft;u32 hash_val;u16 hash_table[4];u8 rcr = RCR_DIS_LONG | RCR_DIS_CRC | RCR_RXEN;dm9000_dbg(db, 1, "entering %s\n", __func__);for (i = 0, oft = DM9000_PAR; i < 6; i++, oft++)iow(db, oft, dev->dev_addr[i]);/* Clear Hash Table */for (i = 0; i < 4; i++)hash_table[i] = 0x0;/* broadcast address */hash_table[3] = 0x8000;if (dev->flags & IFF_PROMISC)rcr |= RCR_PRMSC;if (dev->flags & IFF_ALLMULTI)rcr |= RCR_ALL;/* the multicast address in Hash Table : 64 bits */netdev_for_each_mc_addr(ha, dev) {hash_val = ether_crc_le(6, ha->addr) & 0x3f;hash_table[hash_val / 16] |= (u16) 1 << (hash_val % 16);}/* Write the hash table to MAC MD table */for (i = 0, oft = DM9000_MAR; i < 4; i++) {iow(db, oft++, hash_table[i]);iow(db, oft++, hash_table[i] >> 8);}iow(db, DM9000_RCR, rcr);}static voiddm9000_hash_table(struct net_device *dev){board_info_t *db = netdev_priv(dev);unsigned long flags;spin_lock_irqsave(&db->lock, flags);dm9000_hash_table_unlocked(dev);spin_unlock_irqrestore(&db->lock, flags);}/* * Initialize dm9000 board */static voiddm9000_init_dm9000(struct net_device *dev){board_info_t *db = netdev_priv(dev);unsigned int imr;unsigned int ncr;dm9000_dbg(db, 1, "entering %s\n", __func__);/* I/O mode */db->io_mode = ior(db, DM9000_ISR) >> 6;/* ISR bit7:6 keeps I/O mode *//* Checksum mode */dm9000_set_rx_csum_unlocked(dev, db->rx_csum);/* GPIO0 on pre-activate PHY */iow(db, DM9000_GPR, 0);/* REG_1F bit0 activate phyxcer */iow(db, DM9000_GPCR, GPCR_GEP_CNTL);/* Let GPIO0 output */iow(db, DM9000_GPR, 0);/* Enable PHY */ncr = (db->flags & DM9000_PLATF_EXT_PHY) ? NCR_EXT_PHY : 0;/* if wol is needed, then always set NCR_WAKEEN otherwise we end * up dumping the wake events if we disable this. There is already * a wake-mask in DM9000_WCR */if (db->wake_supported)ncr |= NCR_WAKEEN;iow(db, DM9000_NCR, ncr);/* Program operating register */iow(db, DM9000_TCR, 0); /* TX Polling clear */iow(db, DM9000_BPTR, 0x3f);/* Less 3Kb, 200us */iow(db, DM9000_FCR, 0xff);/* Flow Control */iow(db, DM9000_SMCR, 0); /* Special Mode *//* clear TX status */iow(db, DM9000_NSR, NSR_WAKEST | NSR_TX2END | NSR_TX1END);iow(db, DM9000_ISR, ISR_CLR_STATUS); /* Clear interrupt status *//* Set address filter table */dm9000_hash_table_unlocked(dev);imr = IMR_PAR | IMR_PTM | IMR_PRM;if (db->type != TYPE_DM9000E)imr |= IMR_LNKCHNG;db->imr_all = imr;/* Enable TX/RX interrupt mask */iow(db, DM9000_IMR, imr);/* Init Driver variable */db->tx_pkt_cnt = 0;db->queue_pkt_len = 0;dev->trans_start = jiffies;}/* Our watchdog timed out. Called by the networking layer */static void dm9000_timeout(struct net_device *dev){board_info_t *db = netdev_priv(dev);u8 reg_save;unsigned long flags;/* Save previous register address */reg_save = readb(db->io_addr);spin_lock_irqsave(&db->lock, flags);netif_stop_queue(dev);dm9000_reset(db);dm9000_init_dm9000(dev);/* We can accept TX packets again */dev->trans_start = jiffies; /* prevent tx timeout */netif_wake_queue(dev);/* Restore previous register address */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock, flags);}static void dm9000_send_packet(struct net_device *dev, int ip_summed, u16 pkt_len){board_info_t *dm = to_dm9000_board(dev);/* The DM9000 is not smart enough to leave fragmented packets alone. */if (dm->ip_summed != ip_summed) {if (ip_summed == CHECKSUM_NONE)iow(dm, DM9000_TCCR, 0);elseiow(dm, DM9000_TCCR, TCCR_IP | TCCR_UDP | TCCR_TCP);dm->ip_summed = ip_summed;}/* Set TX length to DM9000 *//* 设置TX数据的长度到寄存器TXPLL和TXPLH */iow(dm, DM9000_TXPLL, pkt_len);iow(dm, DM9000_TXPLH, pkt_len >> 8);/* Issue TX polling command *//* 设置发送控制寄存器的发送请求位 */iow(dm, DM9000_TCR, TCR_TXREQ);/* Cleared after TX complete */}/* * Hardware start transmission. * Send a packet to media from the upper layer. */static intdm9000_start_xmit(struct sk_buff *skb, struct net_device *dev){unsigned long flags;board_info_t *db = netdev_priv(dev);/* 获取网卡虽有信息的存储结构信息的地址 */dm9000_dbg(db, 3, "%s:\n", __func__);if (db->tx_pkt_cnt > 1)return NETDEV_TX_BUSY;spin_lock_irqsave(&db->lock, flags);/* 获得自旋锁 *//* Move data to DM9000 TX RAM *//*MWCMD 即 Memory data write command with address increment Register(F8H)* 根据 IO 操作模式(8-bit or 16-bit)来增加写指针 1 或 2*/writeb(DM9000_MWCMD, db->io_addr);(db->outblk)(db->io_data, skb->data, skb->len);/* 将数据从sk_buff中copy到网卡的TX SRAM中 */dev->stats.tx_bytes += skb->len;/* 统计发送的字节数 */db->tx_pkt_cnt++;/* 待发送计数 *//* TX control: First packet immediately send, second packet queue */if (db->tx_pkt_cnt == 1) {dm9000_send_packet(dev, skb->ip_summed, skb->len);/* 如果计数为1，直接发送 */} else {/* 如果是第2个，则 *//* Second packet */db->queue_pkt_len = skb->len;db->queue_ip_summed = skb->ip_summed;netif_stop_queue(dev);/* 告诉上层停止发送 */}spin_unlock_irqrestore(&db->lock, flags);/* 解锁 *//* free this SKB ，释放SKB*/dev_kfree_skb(skb);return NETDEV_TX_OK;}/* * DM9000 interrupt handler * receive the packet to upper layer, free the transmitted packet */static void dm9000_tx_done(struct net_device *dev, board_info_t *db){int tx_status = ior(db, DM9000_NSR);/* Got TX status */if (tx_status & (NSR_TX2END | NSR_TX1END)) {/* 第一个或第二个数据包发送完毕 *//* One packet sent complete */db->tx_pkt_cnt--;/* 待发送的数据包个数减1 */dev->stats.tx_packets++;/* 发送的数据包加1 */if (netif_msg_tx_done(db))dev_dbg(db->dev, "tx done, NSR %02x\n", tx_status);/* Queue packet check & send */if (db->tx_pkt_cnt > 0)/* 如果还有数据包 */dm9000_send_packet(dev, db->queue_ip_summed, db->queue_pkt_len);netif_wake_queue(dev);/* 告诉内核，将数据包放入发生那个队列 */}}/* DM9000接收数据后的封装结构体，表示数据包的头4个字节 */struct dm9000_rxhdr {u8RxPktReady;u8RxStatus;__le16RxLen;} __attribute__((__packed__));/* * Received a packet and pass to upper layer * 接收数据包，将数据包传递给上层 */static voiddm9000_rx(struct net_device *dev){board_info_t *db = netdev_priv(dev);/* 得到网卡私有信息数据结构的首地址 */struct dm9000_rxhdr rxhdr;/* 该结构体封装了dm9000接收的数据包信息 */struct sk_buff *skb;u8 rxbyte, *rdptr;bool GoodPacket;int RxLen;/* Check packet ready or not */do {/* MRCMDX是内存数据预取读命令 */ior(db, DM9000_MRCMDX);/* Dummy read *//* Get most updated data */rxbyte = readb(db->io_data);/* Status check: this byte must be 0 or 1 *//* DM9000_PKT_ERR 0x02 ,表示接收出错 */if (rxbyte & DM9000_PKT_ERR) {dev_warn(db->dev, "status check fail: %d\n", rxbyte);/* 输出提示信息 */iow(db, DM9000_RCR, 0x00);/* Stop Device 关闭设备 */iow(db, DM9000_ISR, IMR_PAR);/* Stop INT request 停止中断请求*/return;}/* DM9000_PKT_RDY 0x01 没有准备好，直接返回*/if (!(rxbyte & DM9000_PKT_RDY))return;/* A packet ready now & Get status/length */GoodPacket = true;writeb(DM9000_MRCMD, db->io_addr);/* MRCMD是地址增加的数据读取命令 */(db->inblk)(db->io_data, &rxhdr, sizeof(rxhdr));/* 读取数据，从RX_SRAM到 rxhdr结构体中*/RxLen = le16_to_cpu(rxhdr.RxLen);if (netif_msg_rx_status(db))dev_dbg(db->dev, "RX: status %02x, length %04x\n",rxhdr.RxStatus, RxLen);/* Packet Status check ，检查包的完整性*/if (RxLen < 0x40) {GoodPacket = false;if (netif_msg_rx_err(db))dev_dbg(db->dev, "RX: Bad Packet (runt)\n");}/* 如果数据长度大于DM9000_PKT_MAX ，即 1536 */if (RxLen > DM9000_PKT_MAX) {dev_dbg(db->dev, "RST: RX Len:%x\n", RxLen);}/* rxhdr.RxStatus is identical to RSR register. *//* 这里也是包的检查 */if (rxhdr.RxStatus & (RSR_FOE | RSR_CE | RSR_AE | RSR_PLE | RSR_RWTO | RSR_LCS | RSR_RF)) {GoodPacket = false;if (rxhdr.RxStatus & RSR_FOE) {if (netif_msg_rx_err(db))dev_dbg(db->dev, "fifo error\n");dev->stats.rx_fifo_errors++;}if (rxhdr.RxStatus & RSR_CE) {if (netif_msg_rx_err(db))dev_dbg(db->dev, "crc error\n");dev->stats.rx_crc_errors++;}if (rxhdr.RxStatus & RSR_RF) {if (netif_msg_rx_err(db))dev_dbg(db->dev, "length error\n");dev->stats.rx_length_errors++;}}/* Move data from DM9000 ，从DM9000获取数据*/if (GoodPacket && ((skb = dev_alloc_skb(RxLen + 4)) != NULL)) {skb_reserve(skb, 2);rdptr = (u8 *) skb_put(skb, RxLen - 4);/* Read received packet from RX SRAM *//* 将RX SRAM中的数据读取到skbuff结构体 */(db->inblk)(db->io_data, rdptr, RxLen);dev->stats.rx_bytes += RxLen;/* Pass to upper layer */skb->protocol = eth_type_trans(skb, dev);if (db->rx_csum) {if ((((rxbyte & 0x1c) << 3) & rxbyte) == 0)skb->ip_summed = CHECKSUM_UNNECESSARY;elseskb->ip_summed = CHECKSUM_NONE;}netif_rx(skb);/* 将skbuff结构体发送给上层 */dev->stats.rx_packets++;/* 计数增1 */} else {/* need to dump the packet's data *//* 坏包，丢弃 */(db->dumpblk)(db->io_data, RxLen);}} while (rxbyte & DM9000_PKT_RDY);}static irqreturn_t dm9000_interrupt(int irq, void *dev_id){struct net_device *dev = dev_id;board_info_t *db = netdev_priv(dev);int int_status;unsigned long flags;u8 reg_save;dm9000_dbg(db, 3, "entering %s\n", __func__);/* A real interrupt coming *//* holders of db->lock must always block IRQs */spin_lock_irqsave(&db->lock, flags);/* Save previous register address */reg_save = readb(db->io_addr);/* Disable all interrupts */iow(db, DM9000_IMR, IMR_PAR);/* Got DM9000 interrupt status */int_status = ior(db, DM9000_ISR);/* Got ISR */iow(db, DM9000_ISR, int_status);/* Clear ISR status */if (netif_msg_intr(db))dev_dbg(db->dev, "interrupt status %02x\n", int_status);/* Received the coming packet */if (int_status & ISR_PRS)dm9000_rx(dev);/* Trnasmit Interrupt check */if (int_status & ISR_PTS)dm9000_tx_done(dev, db);if (db->type != TYPE_DM9000E) {if (int_status & ISR_LNKCHNG) {/* fire a link-change request */schedule_delayed_work(&db->phy_poll, 1);}}/* Re-enable interrupt mask */iow(db, DM9000_IMR, db->imr_all);/* Restore previous register address */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock, flags);return IRQ_HANDLED;}static irqreturn_t dm9000_wol_interrupt(int irq, void *dev_id){struct net_device *dev = dev_id;board_info_t *db = netdev_priv(dev);unsigned long flags;unsigned nsr, wcr;spin_lock_irqsave(&db->lock, flags);nsr = ior(db, DM9000_NSR);wcr = ior(db, DM9000_WCR);dev_dbg(db->dev, "%s: NSR=0x%02x, WCR=0x%02x\n", __func__, nsr, wcr);if (nsr & NSR_WAKEST) {/* clear, so we can avoid */iow(db, DM9000_NSR, NSR_WAKEST);if (wcr & WCR_LINKST)dev_info(db->dev, "wake by link status change\n");if (wcr & WCR_SAMPLEST)dev_info(db->dev, "wake by sample packet\n");if (wcr & WCR_MAGICST )dev_info(db->dev, "wake by magic packet\n");if (!(wcr & (WCR_LINKST | WCR_SAMPLEST | WCR_MAGICST)))dev_err(db->dev, "wake signalled with no reason? ""NSR=0x%02x, WSR=0x%02x\n", nsr, wcr);}spin_unlock_irqrestore(&db->lock, flags);return (nsr & NSR_WAKEST) ? IRQ_HANDLED : IRQ_NONE;}#ifdef CONFIG_NET_POLL_CONTROLLER/* *Used by netconsole */static void dm9000_poll_controller(struct net_device *dev){disable_irq(dev->irq);dm9000_interrupt(dev->irq, dev);enable_irq(dev->irq);}#endif/* * Open the interface. * The interface is opened whenever "ifconfig" actives it. */static intdm9000_open(struct net_device *dev){board_info_t *db = netdev_priv(dev);/* 返回board_info_t的地址 */unsigned long irqflags = db->irq_res->flags & IRQF_TRIGGER_MASK;if (netif_msg_ifup(db))dev_dbg(db->dev, "enabling %s\n", dev->name);/* If there is no IRQ type specified, default to something that * may work, and tell the user that this is a problem */if (irqflags == IRQF_TRIGGER_NONE)dev_warn(db->dev, "WARNING: no IRQ resource flags set.\n");irqflags |= IRQF_SHARED;/* 注册中断 */if (request_irq(dev->irq, dm9000_interrupt, irqflags, dev->name, dev))return -EAGAIN;/* Initialize DM9000 board */dm9000_reset(db);/* 复位DM9000 */dm9000_init_dm9000(dev);/* 根据net_device的数据初始化DM9000 *//* Init driver variable */db->dbug_cnt = 0;mii_check_media(&db->mii, netif_msg_link(db), 1);/* 检测mii接口的状态 */netif_start_queue(dev);/* 用来告诉上层网络协定这个驱动程序还有空的缓冲区可用，请把下 一个封包送进来。*//*在probe函数中初始化的等待队列 INIT_DELAYED_WORK(&db->phy_poll, dm9000_poll_work); ＊初始化定时器，调用等待队列*/dm9000_schedule_poll(db);return 0;}/* * Sleep, either by using msleep() or if we are suspending, then * use mdelay() to sleep. */static void dm9000_msleep(board_info_t *db, unsigned int ms){if (db->in_suspend)mdelay(ms);elsemsleep(ms);}/* * Read a word from phyxcer */static intdm9000_phy_read(struct net_device *dev, int phy_reg_unused, int reg){board_info_t *db = netdev_priv(dev);unsigned long flags;unsigned int reg_save;int ret;mutex_lock(&db->addr_lock);spin_lock_irqsave(&db->lock,flags);/* Save previous register address */reg_save = readb(db->io_addr);/* Fill the phyxcer register into REG_0C */iow(db, DM9000_EPAR, DM9000_PHY | reg);iow(db, DM9000_EPCR, EPCR_ERPRR | EPCR_EPOS);/* Issue phyxcer read command */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock,flags);dm9000_msleep(db, 1);/* Wait read complete */spin_lock_irqsave(&db->lock,flags);reg_save = readb(db->io_addr);iow(db, DM9000_EPCR, 0x0);/* Clear phyxcer read command *//* The read data keeps on REG_0D & REG_0E */ret = (ior(db, DM9000_EPDRH) << 8) | ior(db, DM9000_EPDRL);/* restore the previous address */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock,flags);mutex_unlock(&db->addr_lock);dm9000_dbg(db, 5, "phy_read[%02x] -> %04x\n", reg, ret);return ret;}/* * Write a word to phyxcer */static voiddm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value){board_info_t *db = netdev_priv(dev);unsigned long flags;unsigned long reg_save;dm9000_dbg(db, 5, "phy_write[%02x] = %04x\n", reg, value);mutex_lock(&db->addr_lock);spin_lock_irqsave(&db->lock,flags);/* Save previous register address */reg_save = readb(db->io_addr);/* Fill the phyxcer register into REG_0C */iow(db, DM9000_EPAR, DM9000_PHY | reg);/* Fill the written data into REG_0D & REG_0E */iow(db, DM9000_EPDRL, value);iow(db, DM9000_EPDRH, value >> 8);iow(db, DM9000_EPCR, EPCR_EPOS | EPCR_ERPRW);/* Issue phyxcer write command */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock, flags);dm9000_msleep(db, 1);/* Wait write complete */spin_lock_irqsave(&db->lock,flags);reg_save = readb(db->io_addr);iow(db, DM9000_EPCR, 0x0);/* Clear phyxcer write command *//* restore the previous address */writeb(reg_save, db->io_addr);spin_unlock_irqrestore(&db->lock, flags);mutex_unlock(&db->addr_lock);}/* 复位 phy，配置寄存器GPR位0为1，关闭dm9000电源，配置寄存器IMR位7为1，disable中断，配置寄存器RCR，disable接收 */static voiddm9000_shutdown(struct net_device *dev){board_info_t *db = netdev_priv(dev);/* 获取网卡私有信息的地址 *//* RESET device */dm9000_phy_write(dev, 0, MII_BMCR, BMCR_RESET);/* PHY RESET ,复位PHY*/iow(db, DM9000_GPR, 0x01);/* Power-Down PHY ，关闭PHY*/iow(db, DM9000_IMR, IMR_PAR);/* Disable all interrupt ，关闭所有的中断*/iow(db, DM9000_RCR, 0x00);/* Disable RX ,不再接受数据*/}/* * Stop the interface. * The interface is stopped when it is brought. */static intdm9000_stop(struct net_device *ndev){board_info_t *db = netdev_priv(ndev);/* 同上，获取网卡的私有结构信息的地址 */if (netif_msg_ifdown(db))dev_dbg(db->dev, "shutting down %s\n", ndev->name);cancel_delayed_work_sync(&db->phy_poll);/* 终止phy_poll队列中被延迟的任务 */netif_stop_queue(ndev);/* 关闭发送队列 */netif_carrier_off(ndev);/*通知该内核设备载波丢失,大部分涉及实际的物理连接的网络技术提供有一个载波状态,载波存在说明硬件存在并准备好*//* free interrupt */free_irq(ndev->irq, ndev);/* 释放中断 */dm9000_shutdown(ndev);/* 关闭DM9000网卡 */return 0;}static const struct net_device_ops dm9000_netdev_ops = {.ndo_open= dm9000_open,/* 打开设备函数 */.ndo_stop= dm9000_stop,/* 关闭设备函数 */.ndo_start_xmit= dm9000_start_xmit,/* 开始发送数据 */.ndo_tx_timeout= dm9000_timeout,/* 发送超时 */.ndo_set_multicast_list= dm9000_hash_table,/* 设定多播列表 */.ndo_do_ioctl= dm9000_ioctl,/* io操作函数 */.ndo_change_mtu= eth_change_mtu,/* 改变MTU */.ndo_validate_addr= eth_validate_addr,.ndo_set_mac_address= eth_mac_addr,#ifdef CONFIG_NET_POLL_CONTROLLER.ndo_poll_controller= dm9000_poll_controller,#endif};/* * Search DM9000 board, allocate space and register it */static int __devinitdm9000_probe(struct platform_device *pdev){struct dm9000_plat_data *pdata = pdev->dev.platform_data;struct board_info *db;/* Point a board information structure */struct net_device *ndev;/* 网络设备 */const unsigned char *mac_src;int ret = 0;int iosize;int i;u32 id_val;unsigned char ne_def_eth_mac_addr[]={0x00,0x12,0x34,0x56,0x80,0x49};/* 设定默认的mac地址 */ static void *bwscon;/* 保存ioremap返回的寄存器的虚拟地址，下同 */ static void *gpfcon; static void *extint0; static void *intmsk; /*Added by yan*/ #define BWSCON (0x48000000) #define GPFCON (0x56000050) #define EXTINT0 (0x56000088) #define INTMSK (0x4A000008) bwscon=ioremap_nocache(BWSCON,0x0000004); gpfcon=ioremap_nocache(GPFCON,0x0000004); extint0=ioremap_nocache(EXTINT0,0x0000004); intmsk=ioremap_nocache(INTMSK,0x0000004); writel( readl(bwscon)|0xc0000,bwscon);/* 将BWSCON寄存器[19:18]设置为11 */ writel( (readl(gpfcon) & ~(0x3 << 14)) | (0x2 << 14), gpfcon); /* 设置GPF寄存器 */ writel( readl(gpfcon) | (0x1 << 7), gpfcon); // Disable pull-up，不使能上拉 writel( (readl(extint0) & ~(0xf << 28)) | (0x4 << 28), extint0); //rising edge，设置上升沿触发中断 writel( (readl(intmsk)) & ~0x80, intmsk);/* 设置中断屏蔽寄存器 */ /*End of add*//* Init network device *//* 使用alloc_etherdev()函数分配一个网络设备的结构体，原型在include/linux/etherdevice.h */ndev = alloc_etherdev(sizeof(struct board_info));if (!ndev) {dev_err(&pdev->dev, "could not allocate device.\n");return -ENOMEM;}/*通过SET_NETDEV_DEV(netdev, &pdev->dev)宏设置net_device.device->parent为当前的pci_device->device*(这儿net_device包含的是device结构，而不是指针）。这样，就建立起了net_device到device的联系。*/SET_NETDEV_DEV(ndev, &pdev->dev);dev_dbg(&pdev->dev, "dm9000_probe()\n");/* setup board info structure *//* 下面都是设置board_info结构体 */db = netdev_priv(ndev);/* 返回dev->priv的地址 */db->dev = &pdev->dev;db->ndev = ndev;spin_lock_init(&db->lock);mutex_init(&db->addr_lock);INIT_DELAYED_WORK(&db->phy_poll, dm9000_poll_work);db->addr_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);db->data_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);db->irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);if (db->addr_res == NULL || db->data_res == NULL || db->irq_res == NULL) {dev_err(db->dev, "insufficient resources\n");ret = -ENOENT;goto out;}db->irq_wake = platform_get_irq(pdev, 1);if (db->irq_wake >= 0) {dev_dbg(db->dev, "wakeup irq %d\n", db->irq_wake);ret = request_irq(db->irq_wake, dm9000_wol_interrupt, IRQF_SHARED, dev_name(db->dev), ndev);if (ret) {dev_err(db->dev, "cannot get wakeup irq (%d)\n", ret);} else {/* test to see if irq is really wakeup capable */ret = set_irq_wake(db->irq_wake, 1);if (ret) {dev_err(db->dev, "irq %d cannot set wakeup (%d)\n",db->irq_wake, ret);ret = 0;} else {set_irq_wake(db->irq_wake, 0);db->wake_supported = 1;}}}iosize = resource_size(db->addr_res);db->addr_req = request_mem_region(db->addr_res->start, iosize, pdev->name);if (db->addr_req == NULL) {dev_err(db->dev, "cannot claim address reg area\n");ret = -EIO;goto out;}db->io_addr = ioremap(db->addr_res->start, iosize);if (db->io_addr == NULL) {dev_err(db->dev, "failed to ioremap address reg\n");ret = -EINVAL;goto out;}iosize = resource_size(db->data_res);db->data_req = request_mem_region(db->data_res->start, iosize, pdev->name);if (db->data_req == NULL) {dev_err(db->dev, "cannot claim data reg area\n");ret = -EIO;goto out;}db->io_data = ioremap(db->data_res->start, iosize);if (db->io_data == NULL) {dev_err(db->dev, "failed to ioremap data reg\n");ret = -EINVAL;goto out;}/* 设置结构体board_info结束 *//* fill in parameters for net-dev structure */ndev->base_addr = (unsigned long)db->io_addr;/* 设置网络设备的地址 */ndev->irq= db->irq_res->start;/* 设置网络设备的中断资源地址 *//* ensure at least we have a default set of IO routines */dm9000_set_io(db, iosize);/* check to see if anything is being over-ridden *//*根据pdev->dev.platform_data的信息判断IO的宽度并设置相应的宽度*/if (pdata != NULL) {/* check to see if the driver wants to over-ride the * default IO width */if (pdata->flags & DM9000_PLATF_8BITONLY)dm9000_set_io(db, 1);if (pdata->flags & DM9000_PLATF_16BITONLY)dm9000_set_io(db, 2);if (pdata->flags & DM9000_PLATF_32BITONLY)dm9000_set_io(db, 4);/* check to see if there are any IO routine * over-rides */if (pdata->inblk != NULL)db->inblk = pdata->inblk;if (pdata->outblk != NULL)db->outblk = pdata->outblk;if (pdata->dumpblk != NULL)db->dumpblk = pdata->dumpblk;db->flags = pdata->flags;}#ifdef CONFIG_DM9000_FORCE_SIMPLE_PHY_POLLdb->flags |= DM9000_PLATF_SIMPLE_PHY;#endifdm9000_reset(db);/* 复位 *//* try multiple times, DM9000 sometimes gets the read wrong */for (i = 0; i < 8; i++) {id_val = ior(db, DM9000_VIDL);id_val |= (u32)ior(db, DM9000_VIDH) << 8;id_val |= (u32)ior(db, DM9000_PIDL) << 16;id_val |= (u32)ior(db, DM9000_PIDH) << 24;if (id_val == DM9000_ID)break;dev_err(db->dev, "read wrong id 0x%08x\n", id_val);}if (id_val != DM9000_ID) {dev_err(db->dev, "wrong id: 0x%08x\n", id_val);ret = -ENODEV;goto out;}/* Identify what type of DM9000 we are working on */id_val = ior(db, DM9000_CHIPR);dev_dbg(db->dev, "dm9000 revision 0x%02x\n", id_val);switch (id_val) {case CHIPR_DM9000A:db->type = TYPE_DM9000A;break;case CHIPR_DM9000B:db->type = TYPE_DM9000B;break;default:dev_dbg(db->dev, "ID %02x => defaulting to DM9000E\n", id_val);db->type = TYPE_DM9000E;}/* dm9000a/b are capable of hardware checksum offload */if (db->type == TYPE_DM9000A || db->type == TYPE_DM9000B) {db->can_csum = 1;db->rx_csum = 1;ndev->features |= NETIF_F_IP_CSUM;}/* from this point we assume that we have found a DM9000 *//* driver system function */ether_setup(ndev);ndev->netdev_ops= &dm9000_netdev_ops;ndev->watchdog_timeo= msecs_to_jiffies(watchdog);ndev->ethtool_ops= &dm9000_ethtool_ops;db->msg_enable = NETIF_MSG_LINK;db->mii.phy_id_mask = 0x1f;db->mii.reg_num_mask = 0x1f;db->mii.force_media = 0;db->mii.full_duplex = 0;db->mii.dev = ndev;db->mii.mdio_read = dm9000_phy_read;db->mii.mdio_write = dm9000_phy_write;mac_src = "eeprom";/* try reading the node address from the attached EEPROM */for (i = 0; i < 6; i += 2)dm9000_read_eeprom(db, i / 2, ndev->dev_addr+i);if (!is_valid_ether_addr(ndev->dev_addr) && pdata != NULL) {mac_src = "platform data";memcpy(ndev->dev_addr, pdata->dev_addr, 6);}if (!is_valid_ether_addr(ndev->dev_addr)) {/* try reading from mac */mac_src = "chip";for (i = 0; i < 6; i++)ndev->dev_addr[i] = ne_def_eth_mac_addr[i];}if (!is_valid_ether_addr(ndev->dev_addr))dev_warn(db->dev, "%s: Invalid ethernet MAC address. Please " "set using ifconfig\n", ndev->name);/* 设置pdev->dev->driver_data为ndev，保存成平台设备总线上的数据，以后使用只需platform_get_drvdata()即可*/platform_set_drvdata(pdev, ndev);/* 注册该网络设备 */ret = register_netdev(ndev);if (ret == 0)printk(KERN_INFO "%s: dm9000%c at %p,%p IRQ %d MAC: %pM (%s)\n", ndev->name, dm9000_type_to_char(db->type), db->io_addr, db->io_data, ndev->irq, ndev->dev_addr, mac_src);return 0;/* 异常处理 */out:dev_err(db->dev, "not found (%d).\n", ret);dm9000_release_board(pdev, db);free_netdev(ndev);return ret;}/* 该函数是将设备从内核中移除，释放资源，在移除设备驱动时执行 */static int __devexitdm9000_drv_remove(struct platform_device *pdev){struct net_device *ndev = platform_get_drvdata(pdev);/* 从总线获取probe函数保存到总线的设备信息 */platform_set_drvdata(pdev, NULL);/* 释放pdev资源 */unregister_netdev(ndev);/* 解除网络设备 */dm9000_release_board(pdev, (board_info_t *) netdev_priv(ndev));/* 释放该设备申请的IO资源 */free_netdev(ndev);/* free device structure */dev_dbg(&pdev->dev, "released and freed device\n");return 0;}/*平台设备驱动的结构体定义*在该结构体中可以定义有关Power Management的管理函数*该驱动中将其省略，侧重分析dm9000的基本原理*/static struct platform_driver dm9000_driver = {.driver= {.name = "dm9000",/* 该名称和系统初始化中，平台设备的名称一致 */.owner = THIS_MODULE,},.probe = dm9000_probe,/* 资源探测函数 */.remove = __devexit_p(dm9000_drv_remove),/* 设备移除函数 */};static int __initdm9000_init(void){printk(KERN_INFO "%s Ethernet Driver, V%s\n", CARDNAME, DRV_VERSION);return platform_driver_register(&dm9000_driver);}static void __exitdm9000_cleanup(void){platform_driver_unregister(&dm9000_driver);}module_init(dm9000_init);module_exit(dm9000_cleanup);MODULE_AUTHOR("Modified by yan");MODULE_DESCRIPTION("Davicom DM9000 network driver");MODULE_LICENSE("GPL");MODULE_ALIAS("platform:dm9000");