/* * Initilize dm9000 board 配置DM9000芯片内部寄存器,使其能工作 */ static void dm9000_init_dm9000(struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv;
PRINTK1("entering %s\n",__FUNCTION__);
/* I/O mode 检查当前芯片的总线带宽8bit,16bit,32bit 芯片的总线带宽由硬件走线决定 */ db->io_mode = ior(db, DM9000_ISR) >> 6; /* ISR bit7:6 keeps I/O mode */
/* GPIO0 on pre-activate PHY 启动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 */
/* Program operating register */ /*清除发送配置选项*/ 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 */ /*清除发送标志位*/ iow(db, DM9000_NSR, NSR_WAKEST | NSR_TX2END | NSR_TX1END); /*清除中断标志位*/ iow(db, DM9000_ISR, ISR_CLR_STATUS); /* Clear interrupt status */
/* Set address filter table */ dm9000_hash_table(dev);
/* Activate DM9000 接收包大小不能超过1.5k,CRC错误的抛弃,使能接收*/ iow(db, DM9000_RCR, RCR_DIS_LONG | RCR_DIS_CRC | RCR_RXEN); /* Enable TX/RX interrupt mask 使用发送,接收中断。SRAM缓冲区指针自动回0 */ iow(db, DM9000_IMR, IMR_PAR | IMR_PTM | IMR_PRM);
/* Init Driver variable */ db->tx_pkt_cnt = 0; db->queue_pkt_len = 0; dev->trans_start = 0; }
/* * Hardware start transmission. * Send a packet to media from the upper layer. */ static int dm9000_start_xmit(struct sk_buff *skb, struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv;
PRINTK3("dm9000_start_xmit\n");
if (db->tx_pkt_cnt > 1) return 1; /*停止接收*/ netif_stop_queue(dev);
/* Disable all interrupts 关闭发送,接收中断*/ iow(db, DM9000_IMR, IMR_PAR);
/* Move data to DM9000 TX RAM */ writeb(DM9000_MWCMD, db->io_addr); /*把skb的数据拷贝到DM9000的SRAM中*/ (db->outblk)(db->io_data, skb->data, skb->len); /*统计值加上相应的长度*/ db->stats.tx_bytes += skb->len;
/* TX control: First packet immediately send, second packet queue */ if (db->tx_pkt_cnt == 0) {
/* First Packet 发送的包增加*/ db->tx_pkt_cnt++;
/* Set TX length to DM9000 设定DM9000需要发送的包长度*/ iow(db, DM9000_TXPLL, skb->len & 0xff); iow(db, DM9000_TXPLH, (skb->len >> 8) & 0xff);
/* Issue TX polling command 设定发送请求,即启动发送*/ iow(db, DM9000_TCR, TCR_TXREQ); /* Cleared after TX complete */ /*启动时间*/ dev->trans_start = jiffies; /* save the time stamp */
} else { /*第二个包发送,在tx_done中实现*/ /* Second packet */ db->tx_pkt_cnt++; db->queue_pkt_len = skb->len; }
/* free this SKB 发送完毕释放skb */ dev_kfree_skb(skb);
/* Re-enable resource check 第一个包发送完毕,即内存拷贝完毕,不是实际总线上的 可以启动第二包拷贝到SRAM*/ if (db->tx_pkt_cnt == 1) netif_wake_queue(dev);
/* Re-enable interrupt 重新启用中断,这时DM9000若发送完成,会产生发送完毕中断*/ iow(db, DM9000_IMR, IMR_PAR | IMR_PTM | IMR_PRM);
return 0; }
static void dm9000_shutdown(struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv;
/* RESET device */ dm9000_phy_write(dev, 0, MII_BMCR, BMCR_RESET); /* PHY RESET */ /*关闭PHY*/ iow(db, DM9000_GPR, 0x01); /* Power-Down PHY */ /*屏蔽所有中断*/ iow(db, DM9000_IMR, IMR_PAR); /* Disable all interrupt */ /*禁用接收*/ iow(db, DM9000_RCR, 0x00); /* Disable RX */ }
/* * Stop the interface. * The interface is stopped when it is brought. */ static int dm9000_stop(struct net_device *ndev) { board_info_t *db = (board_info_t *) ndev->priv;
PRINTK1("entering %s\n",__FUNCTION__);
/* deleted timer 删除内核定时器*/ del_timer(&db->timer); /*通知内核队列不可用*/ netif_stop_queue(ndev); /*linkstat 状态断路*/ netif_carrier_off(ndev);
/* free interrupt 释放中断*/ free_irq(ndev->irq, ndev); /*硬件上关闭芯片*/ dm9000_shutdown(ndev);
return 0; }
/* * 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 */
/*一个包已经发送完毕*/ if (tx_status & (NSR_TX2END | NSR_TX1END)) { /* One packet sent complete */ db->tx_pkt_cnt--; db->stats.tx_packets++;
/* Queue packet check & send 当前还有一个包未发送,且在缓冲区中,是第二个包*/ if (db->tx_pkt_cnt > 0) { /*设定DM9000发送包的长度*/ iow(db, DM9000_TXPLL, db->queue_pkt_len & 0xff); iow(db, DM9000_TXPLH, (db->queue_pkt_len >> 8) & 0xff); /*启动发送*/ iow(db, DM9000_TCR, TCR_TXREQ); dev->trans_start = jiffies; } /*通知内核*/ netif_wake_queue(dev); } }
static irqreturn_t dm9000_interrupt(int irq, void *dev_id) { struct net_device *dev = dev_id; board_info_t *db; int int_status; u8 reg_save;
PRINTK3("entering %s\n",__FUNCTION__);
if (!dev) { PRINTK1("dm9000_interrupt() without DEVICE arg\n"); return IRQ_HANDLED; }
/* A real interrupt coming */ db = (board_info_t *) dev->priv; spin_lock(&db->lock);
/* Save previous register address */ /*保存寄存器值*/ reg_save = readb(db->io_addr);
/* Disable all interrupts 关闭所有中断*/ 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 */
/* Received the coming packet 接收包中断*/ if (int_status & ISR_PRS) dm9000_rx(dev);
/* Trnasmit Interrupt check 发送包中断*/ if (int_status & ISR_PTS) dm9000_tx_done(dev, db);
/* Re-enable interrupt mask */ iow(db, DM9000_IMR, IMR_PAR | IMR_PTM | IMR_PRM);
/* Restore previous register address */ writeb(reg_save, db->io_addr);
spin_unlock(&db->lock);
return IRQ_HANDLED; }
/* * Get statistics from driver. 获取网卡接口统计信息 */ static struct net_device_stats * dm9000_get_stats(struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv; return &db->stats; }
/* * A periodic timer routine * Dynamic media sense, allocated Rx buffer... */ static void dm9000_timer(unsigned long data) { struct net_device *dev = (struct net_device *) data; board_info_t *db = (board_info_t *) dev->priv;
PRINTK3("dm9000_timer()\n"); /*检查mii接口*/ mii_check_media(&db->mii, netif_msg_link(db), 0);
/* Set timer again 重新启动内核定时器,周期检查mii接口 */ db->timer.expires = DM9000_TIMER_WUT; add_timer(&db->timer); } /*DM9000接收包头,芯片提供 01,status,length low,length high*/ struct dm9000_rxhdr { u16 RxStatus; u16 RxLen; } __attribute__((__packed__));
/* * Received a packet and pass to upper layer */ static void dm9000_rx(struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv; struct dm9000_rxhdr rxhdr; struct sk_buff *skb; u8 rxbyte, *rdptr; bool GoodPacket; int RxLen;
/* Check packet ready or not */ do { ior(db, DM9000_MRCMDX); /* Dummy read */
/* Get most updated data */ rxbyte = readb(db->io_data);
/* Status check: this byte must be 0 or 1 接收包最长为1536 */ if (rxbyte > DM9000_PKT_RDY) { printk("status check failed: %d\n", rxbyte); iow(db, DM9000_RCR, 0x00); /* Stop Device */ iow(db, DM9000_ISR, IMR_PAR); /* Stop INT request */ return; }
if (rxbyte != DM9000_PKT_RDY) return;
/* A packet ready now & Get status/length */ GoodPacket = true; writeb(DM9000_MRCMD, db->io_addr); /*获取接收数据包头,共4字节,参考DM9000手册*/ (db->inblk)(db->io_data, &rxhdr, sizeof(rxhdr)); /*查看包长*/ RxLen = rxhdr.RxLen;
/* Packet Status check 包长不能小于64字节*/ if (RxLen < 0x40) { GoodPacket = false; PRINTK1("Bad Packet received (runt)\n"); } /*包长不能大于1536字节*/ if (RxLen > DM9000_PKT_MAX) { PRINTK1("RST: RX Len:%x\n", RxLen); } /*接收的包有错误*/ if (rxhdr.RxStatus & 0xbf00) { GoodPacket = false; if (rxhdr.RxStatus & 0x100) { PRINTK1("fifo error\n"); db->stats.rx_fifo_errors++; } if (rxhdr.RxStatus & 0x200) { PRINTK1("crc error\n"); db->stats.rx_crc_errors++; } if (rxhdr.RxStatus & 0x8000) { PRINTK1("length error\n"); db->stats.rx_length_errors++; } }
/* Move data from DM9000 接收的包没有任何问题时*/ 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 */ /*数据从DM9000内存拷贝到skb*/ (db->inblk)(db->io_data, rdptr, RxLen); /*更新接收字节数统计*/ db->stats.rx_bytes += RxLen;
/* Pass to upper layer */ skb->protocol = eth_type_trans(skb, dev); /*通知上层有新的skb收到*/ netif_rx(skb); /*接收包更新*/ db->stats.rx_packets++;
} else { /* need to dump the packet's data */
(db->dumpblk)(db->io_data, RxLen); } } while (rxbyte == DM9000_PKT_RDY); }
/* * Read a word data from SROM 从EEPROM9346中读取数据 16bit */ static u16 read_srom_word(board_info_t * db, int offset) { iow(db, DM9000_EPAR, offset); iow(db, DM9000_EPCR, EPCR_ERPRR); mdelay(8); /* according to the datasheet 200us should be enough, but it doesn't work */ iow(db, DM9000_EPCR, 0x0); return (ior(db, DM9000_EPDRL) + (ior(db, DM9000_EPDRH) << 8)); }
#ifdef DM9000_PROGRAM_EEPROM /* * Write a word data to SROM 向EEPROM 9346中写数据 16bit */ static void write_srom_word(board_info_t * db, int offset, u16 val) { iow(db, DM9000_EPAR, offset); iow(db, DM9000_EPDRH, ((val >> 8) & 0xff)); iow(db, DM9000_EPDRL, (val & 0xff)); iow(db, DM9000_EPCR, EPCR_WEP | EPCR_ERPRW); mdelay(8); /* same shit */ iow(db, DM9000_EPCR, 0); }
/* * Only for development: * Here we write static data to the eeprom in case * we don't have valid content on a new board */ static void program_eeprom(board_info_t * db) { u16 eeprom[] = { 0x0c00, 0x007f, 0x1300, /* MAC Address */ 0x0000, /* Autoload: accept nothing */ 0x0a46, 0x9000, /* Vendor / Product ID */ 0x0000, /* pin control */ 0x0000, }; /* Wake-up mode control */ int i; for (i = 0; i < 8; i++) write_srom_word(db, i, eeprom[i]); } #endif
/* * Calculate the CRC valude of the Rx packet * flag = 1 : return the reverse CRC (for the received packet CRC) * 0 : return the normal CRC (for Hash Table index) 计算接收包的crc值 */
static unsigned long cal_CRC(unsigned char *Data, unsigned int Len, u8 flag) {
u32 crc = ether_crc_le(Len, Data);
if (flag) return ~crc;
return crc; }
/* * Set DM9000 multicast address */ static void dm9000_hash_table(struct net_device *dev) { board_info_t *db = (board_info_t *) dev->priv; struct dev_mc_list *mcptr = dev->mc_list; int mc_cnt = dev->mc_count; u32 hash_val; u16 i, oft, hash_table[4]; unsigned long flags;
PRINTK2("dm9000_hash_table()\n");
spin_lock_irqsave(&db->lock,flags);
for (i = 0, oft = 0x10; 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;
/* the multicast address in Hash Table : 64 bits */ for (i = 0; i < mc_cnt; i++, mcptr = mcptr->next) { hash_val = cal_CRC((char *) mcptr->dmi_addr, 6, 0) & 0x3f; hash_table[hash_val / 16] |= (u16) 1 << (hash_val % 16); }
/* Write the hash table to MAC MD table */ for (i = 0, oft = 0x16; i < 4; i++) { iow(db, oft++, hash_table[i] & 0xff); iow(db, oft++, (hash_table[i] >> 8) & 0xff); }
spin_unlock_irqrestore(&db->lock,flags); }
/* * Read a word from phyxcer 从PHY读取数据16bit */ static int dm9000_phy_read(struct net_device *dev, int phy_reg_unused, int reg) { board_info_t *db = (board_info_t *) dev->priv; unsigned long flags; unsigned int reg_save; int ret;
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, 0xc); /* Issue phyxcer read command */ udelay(100); /* Wait read complete */ 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);
return ret; }
/* * Write a word to phyxcer 向PHY写入数据16bit */ static void dm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value) { board_info_t *db = (board_info_t *) dev->priv; unsigned long flags; unsigned long reg_save;
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 & 0xff)); iow(db, DM9000_EPDRH, ((value >> 8) & 0xff));
iow(db, DM9000_EPCR, 0xa); /* Issue phyxcer write command */ udelay(500); /* Wait write complete */ 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); }
/*挂起网卡接口*/ static int dm9000_drv_suspend(struct platform_device *dev, pm_message_t state) { struct net_device *ndev = platform_get_drvdata(dev);
if (ndev) { if (netif_running(ndev)) { /*内核临时删除接口*/ netif_device_detach(ndev); /*关闭设备*/ dm9000_shutdown(ndev); } } return 0; }
static int dm9000_drv_resume(struct platform_device *dev) { struct net_device *ndev = platform_get_drvdata(dev); board_info_t *db = (board_info_t *) ndev->priv;
if (ndev) {
if (netif_running(ndev)) { /*复位设备*/ dm9000_reset(db); dm9000_init_dm9000(ndev); /*恢复接口*/ netif_device_attach(ndev); } } return 0; }
static int dm9000_drv_remove(struct platform_device *pdev) { struct net_device *ndev = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL); /*释放注册的网络接口*/ unregister_netdev(ndev); dm9000_release_board(pdev, (board_info_t *) ndev->priv); /*释放资源*/ free_netdev(ndev); /* free device structure */
PRINTK1("clean_module() exit\n");
return 0; }
static struct platform_driver dm9000_driver = { .driver = { .name = "dm9000", .owner = THIS_MODULE, }, .probe = dm9000_probe, .remove = dm9000_drv_remove, .suspend = dm9000_drv_suspend, .resume = dm9000_drv_resume, };
static int __init dm9000_init(void) { printk(KERN_INFO "%s Ethernet Driver\n", CARDNAME);
return platform_driver_register(&dm9000_driver); /* search board and register */ }
static void __exit dm9000_cleanup(void) { platform_driver_unregister(&dm9000_driver); }
module_init(dm9000_init); module_exit(dm9000_cleanup);
MODULE_AUTHOR("Sascha Hauer, Ben Dooks"); MODULE_DESCRIPTION("Davicom DM9000 network driver"); MODULE_LICENSE("GPL");
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