网卡DM9000的驱动移植

    废话不说，直奔主题吧。

要想成功移植DM9000的驱动，首先应该了解Linux内核中platform驱动模型架构和网卡DM9000与cpu的硬件连接，

一、硬件链接情况

    DM9000在电路板上的连接中与编程相关的如下：
1)EECS拉高：16bit模式；
2)INT连接到2440 EINT18：INT脚为低时为有效中断信号，中断线为EINT18
3)cs连接到2440的nGCS4，CMD连接2440地址总线ADDR[2]：知道上面这些信息已经足够移植驱动了。

二、platform驱动模型

      从Linux 2.6起引入了一套新的驱动管理和注册机制:Platform_device和Platform_driver。Linux中大部分的设备驱动，都可以使用这套机制, 设备用Platform_device表示，驱动用Platform_driver进行注册。

    Linux platform driver机制和传统的device driver 机制(通过driver_register函数进行注册)相比，一个十分明显的优势在于platform机制将设备本身的资源注册进内核，由内核统一管理，在驱动程序中使用这些资源时通过platform device提供的标准接口进行申请并使用。这样提高了驱动和资源管理的独立性，并且拥有较好的可移植性和安全性(这些标准接口是安全的)。

    Platform机制的本身使用并不复杂，由两部分组成：platform_device和platfrom_driver。通过Platform机制开发发底层驱动的大致流程为:  定义 platform_device à 注册 platform_device à 定义 platform_driver à注册 platform_driver。

    首先要确认的就是设备的资源信息，例如设备的地址，中断号等。

在2.6内核中platform设备用结构体platform_device来描述，该结构体定义在kernel/include/linux/platform_device.h中，

struct platform_device {

 const char * name;

 u32  id;

 struct device dev;

 u32  num_resources;

 struct resource * resource;

};

 

该结构一个重要的元素是resource，该元素存入了最为重要的设备资源信息，定义在kernel/include/linux/ioport.h中，

struct resource {

 const char *name;

 unsigned long start, end;

 unsigned long flags;

 struct resource *parent, *sibling, *child;

};

 

一个独立的挂接在cpu总线上的设备单元,一般都需要一段线性的地址空间来描述设备自身,linux是怎么管理所有的这些外部"物理地址范围段",进而给用户和linux自身一个比较好的观察4G总线上挂接的一个个设备实体的简洁、统一级联视图的呢?
    linux采用struct resource结构体来描述一个挂接在cpu总线上的设备实体(32位cpu的总线地址范围是0~4G):
resource->start描述设备实体在cpu总线上的线性起始物理地址;
resource->end -描述设备实体在cpu总线上的线性结尾物理地址;
resource->name 描述这个设备实体的名称,这个名字开发人员可以随意起,但最好贴切;
resource->flag 描述这个设备实体的一些共性和特性的标志位;

 

问题:我怎样知道设备实体在cpu总线上的线性起始物理地址跟线性结尾物理地址？

通过查看原理图吗？？如果是，那具体应该怎样分析呢？

三、现在分析dm9000在Linux内核中的结构。

    static struct platform_device与static struct platform_resources结构体在arch/arm/plat-s3c24xx/devs.c中定义，在arch/arm/plat-s3c/include/plat/devs.h中声明，在arch/arm/mach-s3c2440/mach-smdk2440.c中使用（通过函数：platform_add_devices()注册进内核）。

至于platform_driver的实现就是在dm900.c中实现了。

四、移植

 

从上图可以看出

a. dm9000的访问地址为BANK4的基址（也许是通过上面的nGCS4看出来的）。（这个我是不明白的）
b. 只有一根地址线ADDR2。
c. 总线位宽为16位，有nWAIT信号。
d. 使用中断引脚为EINT18（使用LAN_INT实现的）。

一 增加DM9000平台设备
增加平台设备前首先要先定义该平台设备，这主要修改arch/arm/plat-s3c24xx/devs.c文件。
1.添加头文件 ，在devs.c文件的头文件引入处添加如下代码：

#include <linux/dm9000.h>

2.定义dm9000平台资源 ，在devs.c文件的合适处添加如下代码（其实看一下源文件就知道合适的意思）：

 

view plaincopy to clipboardprint? ·········10········20········30········40········50········60········70········80········90········100·······110·······120·······130·······140·······150 1. /* DM9000 */ 2. static struct resource s3c_dm9k_resource[] = { 3. [0] = { 4. .start = S3C2410_CS4, 5. .end = S3C2410_CS4 + 3, 6. .flags = IORESOURCE_MEM, 7. }, 8. [1] = { 9. .start = S3C2410_CS4 + 4, 10. .end = S3C2410_CS4 + 4 + 3, 11. .flags = IORESOURCE_MEM, 12. }, 13. [2] = { 14. .start = IRQ_EINT7, 15. .end = IRQ_EINT7, 16. .flags = IORESOURCE_IRQ | IRQF_TRIGGER_RISING, 17. } 18. 19. }; 20. 21. /* for the moment we limit ourselves to 16bit IO until some 22. * better IO routines can be written and tested 23. */ 24. 25. static struct dm9000_plat_data s3c_dm9k_platdata = { 26. .flags = DM9000_PLATF_16BITONLY, 27. }; 28. 29. struct platform_device s3c_device_dm9k = { 30. .name = "dm9000", 31. .id = 0, 32. .num_resources = ARRAY_SIZE(s3c_dm9k_resource), 33. .resource = s3c_dm9k_resource, 34. .dev = { 35. .platform_data = &s3c_dm9k_platdata, 36. } 37. }; 38. 39. EXPORT_SYMBOL(s3c_device_dm9k);

 

 

1. /* DM9000 */ 2. static struct resource s3c_dm9k_resource[] = { 3. [0] = { 4. .start = S3C2410_CS4, 5. .end = S3C2410_CS4 + 3, 6. .flags = IORESOURCE_MEM, 7. }, 8. [1] = { 9. .start = S3C2410_CS4 + 4, 10. .end = S3C2410_CS4 + 4 + 3, 11. .flags = IORESOURCE_MEM, 12. }, 13. [2] = { 14. .start = IRQ_EINT7, 15. .end = IRQ_EINT7, 16. .flags = IORESOURCE_IRQ | IRQF_TRIGGER_RISING, 17. } 18. 19. }; 20. 21. /* for the moment we limit ourselves to 16bit IO until some 22. * better IO routines can be written and tested 23. */ 24. 25. static struct dm9000_plat_data s3c_dm9k_platdata = { 26. .flags = DM9000_PLATF_16BITONLY, 27. }; 28. 29. struct platform_device s3c_device_dm9k = { 30. .name = "dm9000", 31. .id = 0, 32. .num_resources = ARRAY_SIZE(s3c_dm9k_resource), 33. .resource = s3c_dm9k_resource, 34. .dev = { 35. .platform_data = &s3c_dm9k_platdata, 36. } 37. }; 38. 39. EXPORT_SYMBOL(s3c_device_dm9k);    

 

NOTE:
a.s3c_dm9k_resource数组定义了3个资源：两个内存空间和一个中断号。数组项0、1定义了访问dm9000时使用的地址。在dm9000的芯片手册上有如下的介绍：

    CMD Command Type
         When high, the access of this command cycle is DATA port
         When low, the access of this command cycle is ADDRESS port

所以数组项0、1的.start域就容易理解了，S3C2410_CS4中addr2为0，表示传输地址；S3C2410_CS4 + 4中addr2为1，表示传输数据。数组项[2]定义的中断号就较容易理解。
b.结构s3c_dm9k_platdata中指定了数据总线宽度为16。
c.结构s3c_device_dm9k就是dm9000的平台设备，其中.resource和.dev项分别指向前面定义的s3c_dm9k_resource和s3c_dm9k_platdata。

3.把定义的平台设备加入到内核设备列表中 ，在common-smdk.c文件的smdk_devs数组中添加一下代码：(我的为mach-mini2440.c文件mini2440_devices数组)

&s3c_device_dm9k,

这样，系统启动时就会把这个数组中的设备注册到内核中。

二 修改dm9000.c文件
对dm9000的枚举最终由dm9000_probe函数来实现。
1.添加头文件 ，在dm9000.c的头文件引入处增加以下代码，定义了一些寄存器的宏定义：

view plain copy to clipboard print ?
#if defined(CONFIG_ARCH_S3C2410)   
#include <mach/regs-mem.h>   
#endif   

view plaincopy to clipboardprint?
#if defined(CONFIG_ARCH_S3C2410)  
#include <mach/regs-mem.h>  
#endif 
#if defined(CONFIG_ARCH_S3C2410)
#include <mach/regs-mem.h>
#endif
 

2.修改probe函数 ，通过设置存储控制器使BANK4可用，修改后的dm9000_probe函数如下，其中修改的地方都由CONFIG_ARCH_S3C2410包括：

 

view plaincopy to clipboardprint? # * # * Search DM9000 board, allocate space and register it # */ # static int __devinit # dm9000_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; # const unsigned char *mac_src; # int ret = 0; # int iosize; # int i; # u32 id_val; # # # if defined(CONFIG_ARCH_S3C2410) # unsigned int oldval_bwscon = *(volatile unsigned int *)S3C2410_BWSCON; # unsigned int oldval_bankcon4 = *(volatile unsigned int *)S3C2410_BANKCON4; # # endif # # /* Init network device */ # ndev = alloc_etherdev(sizeof(struct board_info)); # if (!ndev) { # dev_err(&pdev->dev, "could not allocate device./n"); # return -ENOMEM; # } # # SET_NETDEV_DEV(ndev, &pdev->dev); # # dev_dbg(&pdev->dev, "dm9000_probe()/n"); # # #if defined(CONFIG_ARCH_S3C2410) # *((volatile unsigned int *)S3C2410_BWSCON) = # (oldval_bwscon & ~(3<<16)) | S3C2410_BWSCON_DW4_16 | S3C2410_BWSCON_WS4 | S3C2410_BWSCON_ST4; # *((volatile unsigned int *)S3C2410_BANKCON4) = 0x1f7c; # #endif # # /* setup board info structure */ # db = netdev_priv(ndev); # memset(db, 0, sizeof(*db)); # # 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; # } # # iosize = res_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 = res_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; # } # # /* 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; # # db->flags = pdata->flags; # } # # #ifdef CONFIG_DM9000_FORCE_SIMPLE_PHY_POLL # db->flags |= DM9000_PLATF_SIMPLE_PHY; # #endif # # dm9000_reset(db); # # /* 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; # } # # /* from this point we assume that we have found a DM9000 */ # # /* driver system function */ # ether_setup(ndev); # # ndev->open = &dm9000_open; # ndev->hard_start_xmit = &dm9000_start_xmit; # ndev->tx_timeout = &dm9000_timeout; # ndev->watchdog_timeo = msecs_to_jiffies(watchdog); # ndev->stop = &dm9000_stop; # ndev->set_multicast_list = &dm9000_hash_table; # ndev->ethtool_ops = &dm9000_ethtool_ops; # ndev->do_ioctl = &dm9000_ioctl; # # #ifdef CONFIG_NET_POLL_CONTROLLER # ndev->poll_controller = &dm9000_poll_controller; # #endif # # 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; # # #if defined(CONFIG_ARCH_S3C2410) # printk("Now use the default MAC address: 08:90:90:90:90:90/n"); # mac_src = "friendly-arm"; # ndev->dev_addr[0] = 0x08; # ndev->dev_addr[1] = 0x90; # ndev->dev_addr[2] = 0x90; # ndev->dev_addr[3] = 0x90; # ndev->dev_addr[4] = 0x90; # ndev->dev_addr[5] = 0x90; # #else # 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] = ior(db, i+DM9000_PAR); # } # # if (!is_valid_ether_addr(ndev->dev_addr)) # dev_warn(db->dev, "%s: Invalid ethernet MAC address. Please " # "set using ifconfig/n", ndev->name); # #endif # # platform_set_drvdata(pdev, ndev); # 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; # # out: # #if defined(CONFIG_ARCH_S3C2410) # *(volatile unsigned int *)S3C2410_BWSCON = oldval_bwscon; # *(volatile unsigned int *)S3C2410_BANKCON4 = oldval_bankcon4; # #endif # dev_err(db->dev, "not found (%d)./n", ret); # # dm9000_release_board(pdev, db); # free_netdev(ndev); # # return ret; # } # * # * Search DM9000 board, allocate space and register it # */ # static int __devinit # dm9000_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; # const unsigned char *mac_src; # int ret = 0; # int iosize; # int i; # u32 id_val; # # # if defined(CONFIG_ARCH_S3C2410) # unsigned int oldval_bwscon = *(volatile unsigned int *)S3C2410_BWSCON; # unsigned int oldval_bankcon4 = *(volatile unsigned int *)S3C2410_BANKCON4; # # endif # # /* Init network device */ # ndev = alloc_etherdev(sizeof(struct board_info)); # if (!ndev) { # dev_err(&pdev->dev, "could not allocate device./n"); # return -ENOMEM; # } # # SET_NETDEV_DEV(ndev, &pdev->dev); # # dev_dbg(&pdev->dev, "dm9000_probe()/n"); # # #if defined(CONFIG_ARCH_S3C2410) # *((volatile unsigned int *)S3C2410_BWSCON) = # (oldval_bwscon & ~(3<<16)) | S3C2410_BWSCON_DW4_16 | S3C2410_BWSCON_WS4 | S3C2410_BWSCON_ST4; # *((volatile unsigned int *)S3C2410_BANKCON4) = 0x1f7c; # #endif # # /* setup board info structure */ # db = netdev_priv(ndev); # memset(db, 0, sizeof(*db)); # # 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; # } # # iosize = res_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 = res_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; # } # # /* 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; # # db->flags = pdata->flags; # } # # #ifdef CONFIG_DM9000_FORCE_SIMPLE_PHY_POLL # db->flags |= DM9000_PLATF_SIMPLE_PHY; # #endif # # dm9000_reset(db); # # /* 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; # } # # /* from this point we assume that we have found a DM9000 */ # # /* driver system function */ # ether_setup(ndev); # # ndev->open = &dm9000_open; # ndev->hard_start_xmit = &dm9000_start_xmit; # ndev->tx_timeout = &dm9000_timeout; # ndev->watchdog_timeo = msecs_to_jiffies(watchdog); # ndev->stop = &dm9000_stop; # ndev->set_multicast_list = &dm9000_hash_table; # ndev->ethtool_ops = &dm9000_ethtool_ops; # ndev->do_ioctl = &dm9000_ioctl; # # #ifdef CONFIG_NET_POLL_CONTROLLER # ndev->poll_controller = &dm9000_poll_controller; # #endif # # 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; # # #if defined(CONFIG_ARCH_S3C2410) # printk("Now use the default MAC address: 08:90:90:90:90:90/n"); # mac_src = "friendly-arm"; # ndev->dev_addr[0] = 0x08; # ndev->dev_addr[1] = 0x90; # ndev->dev_addr[2] = 0x90; # ndev->dev_addr[3] = 0x90; # ndev->dev_addr[4] = 0x90; # ndev->dev_addr[5] = 0x90; # #else # 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] = ior(db, i+DM9000_PAR); # } # # if (!is_valid_ether_addr(ndev->dev_addr)) # dev_warn(db->dev, "%s: Invalid ethernet MAC address. Please " # "set using ifconfig/n", ndev->name); # #endif # # platform_set_drvdata(pdev, ndev); # 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; # # out: # #if defined(CONFIG_ARCH_S3C2410) # *(volatile unsigned int *)S3C2410_BWSCON = oldval_bwscon; # *(volatile unsigned int *)S3C2410_BANKCON4 = oldval_bankcon4; # #endif # dev_err(db->dev, "not found (%d)./n", ret); # # dm9000_release_board(pdev, db); # free_netdev(ndev); # # return ret; # }

 

a.第24-27行定义了两个变量，用来保存BWSCON和BANKCON4的值，下面将会用到。

b.第32-39对BANK4进行了设置。首先设置BWSCON，

9对BANK4进行了设置。首先设置BWSCON，

view plain copy to clipboard print ?
#if defined(CONFIG_ARCH_S3C2410) *((volatile unsigned int *)S3C2410_BWSCON) = (oldval_bwscon & ~(3<<16)) | S3C2410_BWSCON_DW4_16 | S3C2410_BWSCON_WS4 | S3C2410_BWSCON_ST4; *((volatile unsigned int *)S3C2410_BANKCON4) = 0x1f7c; #endif view plaincopy to clipboardprint? #if defined(CONFIG_ARCH_S3C2410) *((volatile unsigned int *)S3C2410_BWSCON) = (oldval_bwscon & ~(3<<16)) | S3C2410_BWSCON_DW4_16 | S3C2410_BWSCON_WS4 | S3C2410_BWSCON_ST4; *((volatile unsigned int *)S3C2410_BANKCON4) = 0x1f7c; #endif #if defined(CONFIG_ARCH_S3C2410) *((volatile unsigned int *)S3C2410_BWSCON) = (oldval_bwscon & ~(3<<16)) | S3C2410_BWSCON_DW4_16 | S3C2410_BWSCON_WS4 | S3C2410_BWSCON_ST4; *((volatile unsigned int *)S3C2410_BANKCON4) = 0x1f7c; #endif

 

主要是设置了总线宽度16，nWAIT，ST。（具体的可以参考s3c2440数据手册的BUS WIDTH & WAIT CONTROL REGISTER (BWSCON)）。然后设置BANKCON4的时间参数，值为0×1f7c（pmc:normal Tacp:6clk Tcah:4clk Tcoh:1clk Tacc:14clk Tcos:4clk 具体可以参考s3c2440数据手册的BANK CONTROL REGISTER）

c.第209-216的代码是我自己给注释的，据其意思，上面首先给MAC赋值，然后检测合法性，但经实践，判断语句总成立，所以在linux启动注册dm9000时总输出Invalid ethernet MAC address.反正后面也会再次给MAC地址赋值，所以干脆把这几行代码注释掉。

d.第218-227行就是给MAC地址赋值的，听说赋什么值都可以，有这么神奇吗？

e.第266-269行恢复寄存器原来的值。

f.以上的步骤和代码都是参考书上的，但可惜的是，按照上面步骤去修改，系统能成功加载dm9000驱动，但无法ping通，这个事确实让我很苦恼，上网找了很多资料，最后发现大多数都需要调用writel来设置BWSCON、GPFCON和中断等。所以无计之下参考了mini2440中的一段代码，出自附送光盘的无操作系统代码测试的dm9000部分。

到此 ，代码的移植到此为止，然后是配置内核，以使用dm9000。在

-> Device Drivers                                                   
        --> Network device support                                       
           --> Network device support (NETDEVICES [=y])                      
             --> Ethernet (10 or 100Mbit) 处将DM9000网卡选为编译进内核。
然后在/etc/init.d/rcS文件的开始处加入

ifconfig
 eth0 192.168.1.22<
pre>
当然，ip地址是因人而定的，尽量设为和PC在同一个网段。重新将内核下载到开发板后启动