分类： LINUX
2008-07-10 15:43:32
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＃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 srom[128]; /*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_EEPROM
static void program_eeprom(board_info_t * db);
#endif
/* DM9000 network board routine ---------------------------- */
static void
dm9000_reset(board_info_t * db)
{
PRINTK1("dm9000x: resetting\n");
/* 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 u8
ior(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 void
iow(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 < 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
根据芯片的外部总线带宽，指定对应的输入输出函数
*/
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 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 16bit\n");
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 void
dm9000_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 int
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;
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 < 2) {
ret = -ENODEV;
goto out;
} else if (pdev->num_resources == 2) {
base = pdev->resource[0].start;
if (!request_mem_region(base, 4, ndev->name)) {
ret = -EBUSY;
goto out;
}
ndev->base_addr = base;
ndev->irq = pdev->resource[1].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 resources\n");
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 area\n");
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 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) {
printk(KERN_ERR PFX "cannot claim data reg area\n");
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 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;
}
/*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) << 24;
if (id_val == DM9000_ID)
break;
printk("%s: read wrong id 0x%08x\n", CARDNAME, id_val);
}
/*芯片的ID获取失败，驱动不匹配*/
if (id_val != DM9000_ID) {
printk("%s: wrong id: 0x%08x\n", CARDNAME, id_val);
goto release;
}
/* from this point we assume that we have found a DM9000 */
/* driver system function
将DM9000作为以太网卡初始化内部数据结构*/
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); /*超时值*/
ndev->stop = &dm9000_stop;
ndev->get_stats = &dm9000_get_stats;
ndev->set_multicast_list = &dm9000_hash_table;
#ifdef CONFIG_NET_POLL_CONTROLLER
ndev->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 < 64; i++)
/*采用16bit读取方式*/
((u16 *) db->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 < 6; i++)
ndev->dev_addr[i] = db->srom[i];
/*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 < 6; i++)
ndev->dev_addr[i] = 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 ifconfig\n", 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 < 5; i++)
printk("%02x:", ndev->dev_addr[i]);
printk("%02x\n", ndev->dev_addr[5]);
}
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 int
dm9000_open(struct net_device *dev)
{
board_info_t *db = (board_info_t *) dev->priv;
PRINTK2("entering dm9000_open\n");
/*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 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);
