DM9000驱动解析 收藏.doc

DM9000驱动解析1 收藏 /* dm9000.c: Version 1.2 03/18/2003* A Davicom DM9000 ISA NIC fast Ethernet driver for Linux.* Copyright (C) 1997 Sten Wang* This program is free software; you can redistribute it and/or* modify it under the terms of the GNU General Public License* as published by the Free Software Foundation; either version 2* of the License, or (at your option) any later version.* This program is distributed in the hope that it will be useful,* but WITHOUT ANY WARRANTY; without even the implied warranty of* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the* GNU General Public License for more details.* (C)Copyright 1997-1998 DAVICOM Semiconductor,Inc. All Rights Reserved.* V0.11 06/20/2001 REG_0A bit3=1, default enable BP with DA match* 06/22/2001 Support DM9801 progrmming* E3: R25 = (R24 + NF) & 0x00ff) | 0xf000* E4: R25 = (R24 + NF) & 0x00ff) | 0xc200* R17 = (R17 & 0xfff0) | NF + 3* E5: R25 = (R24 + NF - 3) & 0x00ff) | 0xc200* R17 = (R17 & 0xfff0) | NF* v1.00 modify by simon 2001.9.5* change for kernel 2.4.x* v1.1 11/09/2001 fix force mode bug* v1.2 03/18/2003 Weilun Huang :* Fixed phy reset.* Added tx/rx 32 bit mode.* Cleaned up for kernel merge.* 03/03/2004 Sascha Hauer * Port to 2.6 kernel* 24-Sep-2004 Ben Dooks * Cleanup of code to remove ifdefs* Allowed platform device data to influence access width* Reformatting areas of code* 17-Mar-2005 Sascha Hauer * * removed 2.4 style module parameters* * removed removed unused stat counter and fixed* net_device_stats* * introduced tx_timeout function* * reworked locking* 01-Jul-2005 Ben Dooks * * fixed spinlock call without pointer* * ensure spinlock is initialised*/i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude i nclude dm9000.h/* Board/System/Debug information/definition - */#define DM9000_PHY 0x40 /* PHY address 0x01 */#define CARDNAME dm9000#define PFX CARDNAME : #define DM9000_TIMER_WUT jiffies+(HZ*2) /* timer wakeup time : 2 second */#define DM9000_DEBUG 0#if DM9000_DEBUG 2#define PRINTK3(args.) printk(CARDNAME : args)#else#define PRINTK3(args.) do while(0)#endif#if DM9000_DEBUG 1#define PRINTK2(args.) printk(CARDNAME : args)#else#define PRINTK2(args.) do while(0)#endif#if DM9000_DEBUG 0#define PRINTK1(args.) printk(CARDNAME : args)#define PRINTK(args.) printk(CARDNAME : args)#else#define PRINTK1(args.) do while(0)#define PRINTK(args.) printk(KERN_DEBUG args)#endif/* Transmit timeout, default 5 seconds.*/static int watchdog = 5000;module_param(watchdog, int, 0400);MODULE_PARM_DESC(watchdog, transmit timeout in milliseconds);/*DM9000 含有16K SRAM作为FIFO buffer，3K用于transmitt,13k用于receive*/* Structure/enum declaration - */typedef struct board_info /*命令地址寄存器地址*/void _iomem *io_addr; /* Register I/O base address */*数据寄存器地址*/void _iomem *io_data; /* Data I/O address */u16 irq; /* IRQ */u16 tx_pkt_cnt;u16 queue_pkt_len;u16 queue_start_addr;u16 dbug_cnt;u8 io_mode; /* 0:word, 2:byte */u8 phy_addr;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 resource *addr_res; /* resources found */struct resource *data_res;struct resource *addr_req; /* resources requested */struct resource *data_req;struct resource *irq_res;struct timer_list timer;struct net_device_stats stats;unsigned char srom128; /*网卡上EERPOM的内容*/spinlock_t lock;struct mii_if_info mii; /*调试可能会用到*/u32 msg_enable; board_info_t;/* function declaration - */static int dm9000_probe(struct platform_device *);static int dm9000_open(struct net_device *);static int dm9000_start_xmit(struct sk_buff *, struct net_device *);static int dm9000_stop(struct net_device *);static void dm9000_timer(unsigned long);static void dm9000_init_dm9000(struct net_device *);static struct net_device_stats *dm9000_get_stats(struct net_device *);static irqreturn_t dm9000_interrupt(int, void *);static int dm9000_phy_read(struct net_device *dev, int phyaddr_unsused, int reg);static void dm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value);static u16 read_srom_word(board_info_t *, int);static void dm9000_rx(struct net_device *);static void dm9000_hash_table(struct net_device *);/#define DM9000_PROGRAM_EEPROM#ifdef DM9000_PROGRAM_EEPROMstatic void program_eeprom(board_info_t * db);#endif/* DM9000 network board routine - */static voiddm9000_reset(board_info_t * db)PRINTK1(dm9000x: resettingn);/* RESET device */*指定DM9000当前的命令寄存器是NCR*/writeb(DM9000_NCR, db-io_addr);udelay(200);/*向NCR寄存器写入复位标志，芯片复位*/writeb(NCR_RST, db-io_data);udelay(200);/* Read a byte from I/O port 读取寄存器的值，reg表明寄存器的偏移量 这里用宏名表示*/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 写寄存器的值，reg表明寄存器的偏移量 这里用宏名表示，value是写入数据*/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 */*类似于内存拷贝简单的理解为memcpy(reg,data,count)count是以字节为单位的！*/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 */*类似于内存拷贝简单的理解为memcpy(data,reg,count)count是以字节为单位的！*/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 */*类似于内存清理，将reg指向的count清空。多用于设备的接收缓存区清空count是以字节为单位的！*/static void dm9000_dumpblk_8bit(void _iomem *reg, int count)int i;int tmp;for (i = 0; i 1;for (i = 0; i 2;for (i = 0; i dumpblk = dm9000_dumpblk_8bit; db-outblk = dm9000_outblk_8bit; db-inblk = dm9000_inblk_8bit; break;case 2: db-dumpblk = dm9000_dumpblk_16bit; db-outblk = dm9000_outblk_16bit; db-inblk = dm9000_inblk_16bit; break;case 3: printk(KERN_ERR PFX : 3 byte IO, falling back to 16bitn); 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;/*超时处理函数*/* Our watchdog timed out. Called by the networking layer */static void dm9000_timeout(struct net_device *dev)board_info_t *db = (board_info_t *) dev-priv;u8 reg_save;unsigned long flags;/* Save previous register address */reg_save = readb(db-io_addr);spin_lock_irqsave(&db-lock,flags);/*停止发送报文 */netif_stop_queue(dev);/*复位DM9000芯片*/dm9000_reset(db);/*初始化DM9000芯片*/dm9000_init_dm9000(dev);/* We can accept TX packets again */*重启发送*/dev-trans_start = jiffies;netif_wake_queue(dev);/* Restore previous register address */*io_addr的恢复，保证了芯片的配置和初始值一致*/writeb(reg_save, db-io_addr);spin_unlock_irqrestore(&db-lock,flags);#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/* dm9000_release_board* release a board, and any mapped resources 释放资源*/static voiddm9000_release_board(struct platform_device *pdev, struct board_info *db)if (db-data_res = NULL) if (db-addr_res != NULL) release_mem_region(unsigned long)db-io_addr, 4); return;/* unmap our resources */iounmap(db-io_addr);iounmap(db-io_data);/* release the resources */if (db-data_req != NULL) release_resource(db-data_req); kfree(db-data_req);if (db-addr_req != NULL) release_resource(db-addr_req); kfree(db-addr_req);#define res_size(_r) (_r)-end - (_r)-start) + 1)/* Search DM9000 board, allocate space and register it*/static intdm9000_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;unsigned long base;int ret = 0;int iosize;int i;u32 id_val;/* 分配eth网卡资源，私有数据区保存board_info*/ndev = alloc_etherdev(sizeof (struct board_info);if (!ndev) printk(%s: could not allocate device.n, CARDNAME); return -ENOMEM;/*忽略*/SET_MODULE_OWNER(ndev);SET_NETDEV_DEV(ndev, &pdev-dev);PRINTK2(dm9000_probe();/* setup board info structure bord info初始化为0 */db = (struct board_info *) ndev-priv;memset(db, 0, sizeof (*db);/*初始化spinlock*/spin_lock_init(&db-lock);/*忽略*/if (pdev-num_resources num_resources = 2) base = pdev-resource0.start; if (!request_mem_region(base, 4, ndev-name) ret = -EBUSY; goto out; ndev-base_addr = base; ndev-irq = pdev-resource1.start; db-io_addr = (void _iomem *)base; db-io_data = (void _iomem *)(base + 4); else 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) printk(KERN_ERR PFX insufficient resourcesn); ret = -ENOENT; goto out; i = res_size(db-addr_res); db-addr_req = request_mem_region(db-addr_res-start, i, pdev-name); if (db-addr_req = NULL) printk(KERN_ERR PFX cannot claim address reg arean); ret = -EIO; goto out; db-io_addr = ioremap(db-addr_res-start, i); if (db-io_addr = NULL) printk(KERN_ERR failed to ioremap address regn); ret = -EINVAL; goto out; iosize = res_size(db-data_res); db-data_req = request_mem_region(db-data_res-start, iosize, pdev-name); if (db-data_req = NULL) printk(KERN_ERR PFX cannot claim data reg arean); ret = -EIO; goto out; db-io_data = ioremap(db-data_res-start, iosize); if (db-io_data = NULL) printk(KERN_ERR failed to ioremap data regn); ret = -EINVAL; goto out; /* fill in parameters for net-dev structure */ ndev-base_addr = (unsigned long)db-io_addr; ndev-irq = db-irq_res-start; /* 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 */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;/*根据board info信息，复位DM9000芯片*/dm9000_reset(db);/* try two times, DM9000 sometimes gets the first read wrong */for (i = 0; i 2; 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) open = &dm9000_open;ndev-hard_start_xmit = &dm9000_start_xmit;ndev-tx_timeout = &dm9000_timeout;ndev-watchdog_timeo = msecs_to_jiffies(watchdog); /*超时值*/ndev-stop = &dm9000_stop;ndev-get_stats = &dm9000_get_stats;ndev-set_multicast_list = &dm9000_hash_table;#ifdef CONFIG_NET_POLL_CONTROLLERndev-poll_controller = &dm9000_poll_controller;#endif#ifdef DM9000_PROGRAM_EEPROM/*开发时，需要更新EERPOM的值*/program_eeprom(db);#endif/*忽略*/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; /*DM9000可以提供MII，外接PHY*/db-mii.mdio_write = dm9000_phy_write;/* 获取网卡上EEPROM9346的内容，走EERPOM接口 */for (i = 0; i srom)i = read_srom_word(db, i);/* Set Node Address EEPROM的前6个字节为MAC地址*/for (i = 0; i dev_addri = db-sromi;/*验证获取的MAC地址是否合法*/if (!is_valid_ether_addr(ndev-dev_addr) /* try reading from mac */ /*不合法，重新从DM9000的内部寄存器获取MAC，不走EEPROM接口*/ for (i = 0; i dev_addri = ior(db, i+DM9000_PAR);/*两种方式都失败，提示用ifconfig,驱动没有对应接口！*/if (!is_valid_ether_addr(ndev-dev_addr) printk(%s: Invalid ethernet MAC address. Please set using ifconfign, ndev-name);platform_set_drvdata(pdev, ndev);/*注册接口到系统中，状态默认down，不可用*/ret = register_netdev(ndev);if (ret = 0) printk(%s: dm9000 at %p,%p IRQ %d MAC: , ndev-name, db-io_addr, db-io_data, ndev-irq); for (i = 0; i dev_addri); printk(%02xn, ndev-dev_addr5);return 0;release:out:printk(%s: not found (%d).n, CARDNAME, ret);/失败时，释放资源*/dm9000_release_board(pdev, db);free_netdev(ndev);return ret;/* Open the interface.* The interface is opened whenever ifconfig actives it. 当使用ifconfig激活该网络接口时调用*/static intdm9000_open(struct net_device *dev)board_info_t *db = (board_info_t *) dev-priv;PRINTK2(entering dm9000_openn);/*申请中断资源，注册中断函数*/if (request_irq(dev-irq, &dm9000_interrupt, IRQF_SHARED, dev-name, dev) return -EAGAIN;/* Initialize DM9000 board */*复位DM9000芯片*/dm9000_reset(db);/*配置DM9000芯片内寄存器，使其能工作*/dm9000_init_dm9000(dev);/* Init driver variable */db-dbug_cnt = 0;/* set and active a timer process */init_timer(&db-timer); /*初始化内核定时器*/db-timer.expires = DM9000_TIMER_WUT; /*2s唤醒一次*/db-timer.data = (unsigned long) dev;db-timer.function = &dm9000_timer; /*内核定时器溢出回调函数*/add_timer(&db-timer); /*启动内核定时器*/*检查mii接口状态*/mii_check_media(&db-mii, netif_msg_link(db), 1);/*启动发送队列*/netif_start_queue(dev);return 0;/* Initilize dm9000 board 配置DM9000芯片内部寄存器，使其能工作*/static voiddm9000_init_dm9000(struct net_device *dev)board_info_t *db = (board_info_t *) dev-priv;PRINTK1(entering %sn,_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(d