文章目录
这是个人驱动开发过程中做的一些记录,仅代表个人意见和理解,不喜勿喷
- MAC驱动需要支持不同的PHY芯片
MAC驱动支持不同的PHY芯片
关于对PHY设备抽象的改进
系列文章2中有提及到,在RT-Thread下定义的PHY操作抽象接口并不是很合理,比如你的系统里面有2个PHY的时候,你需要对每个PHY的操作接口和具体的PHY设备实例进行深度绑定,否则你无法根据当前read操作所传入的参数来区分当前操作的是哪个PHY设备:
先让我们来看下按照现有RT-Thread PHY抽象接口的定义,现在需要实现一个获取当前link状态的操作接口的实现,抽象接口的定义和具体实现如下:
rt_phy_status (*get_link_status)(rt_bool_t *status);
c
static rt_phy_status h3_kszplib_read(rt_uint32_t reg, rt_uint32_t *data)
{
rt_mdio_t *mdio_bus = h3_kszdev0.rt_phydev.bus;
rt_uint32_t device_id = h3_kszdev0.rt_phydev.addr;
if (4 != mdio_bus->ops->read(mdio_bus, device_id,
reg, (void *)data, 4))
{
return RT_FALSE;
}
return PHY_STATUS_OK;
}
c
static rt_phy_status h3_kszplib_linkstatus(rt_bool_t *status)
{
rt_phy_status result;
rt_uint32_t data;
/* Read the basic status register. */
result = h3_kszplib_read(MII_MSR, &data);
RESULT_MATCH_CHECK(result, PHY_STATUS_FAIL, outs)
if (!(MII_MSR_LINKSTATUS & data))
{
*status = RT_FALSE; /* link down. */
}
else
{
*status = RT_TRUE; /* link up. */
}
outs:
return result;
}
那对于h3_kszplib_read()接口函数来说,它需要知道自己是属于哪个PHY设备的实例,然后去获取该PHY设备实例下所拥有的MIDO设备和MDIO设备操作接口,也就是说它这个接口的实现和PHY设备实例进行了深度绑定。而我们实际设计中,对于h3_kszplib_read接口函数来说它没有必要去知道自己属于哪个PHY设备实例,它只需要获取到该PHY设备实例所提供的MDIO操作接口信息即可,因为原有的get_link_status()这个抽象接口无法提供PHY设备实例的信息,也就是说它也是和具体PHY设备实例进行了深度绑定,现在我们将对其深度绑定进行解藕操作。
RT-Thread下PHY设备抽象接口的改进
c
struct rt_phy_ops
{
rt_phy_status (*init)(struct rt_phy_device *phy, void *object, rt_uint32_t phy_addr, rt_uint32_t src_clock_hz);
rt_phy_status (*read)(struct rt_phy_device *phy, rt_uint32_t reg, rt_uint32_t *data);
rt_phy_status (*write)(struct rt_phy_device *phy, rt_uint32_t reg, rt_uint32_t data);
rt_phy_status (*loopback)(struct rt_phy_device *phy, rt_uint32_t mode, rt_uint32_t speed, rt_bool_t enable);
rt_phy_status (*get_link_status)(struct rt_phy_device *phy, rt_bool_t *status);
rt_phy_status (*get_link_speed_duplex)(struct rt_phy_device *phy, rt_uint32_t *speed, rt_uint32_t *duplex);
};
在RT-Thread下定义的PHY操作抽象接口中,传入struct rt_phy_device *phy这个参数,后续的驱动代码可以根据传入的参数,来进行进一步的操作,将MDIO具体读写操作的请求独立出来,只需要从PHY设备的实例中获取到MDIO总线和PHY的物理地址,调用MDIO总线实例提供的读写操作接口即可。
c
static rt_phy_status h3_kszplib_read(struct rt_phy_device *phy,
rt_uint32_t reg, rt_uint32_t *data)
{
rt_mdio_t *mdio_bus = phy->bus;
rt_uint32_t phy_addr = phy->addr;
if (4 != mdio_bus->ops->read(mdio_bus, phy_addr, reg, (void *)data, 4))
{
return RT_FALSE;
}
return PHY_STATUS_OK;
}
c
static rt_phy_status h3_kszplib_linkstatus(struct rt_phy_device *phy, rt_bool_t *status)
{
rt_phy_status result;
rt_uint32_t data;
RT_ASSERT(phy != RT_NULL);
/* Read the basic status register. */
result = h3_kszplib_read(phy, MII_MSR, &data);
RESULT_MATCH_CHECK(result, PHY_STATUS_FAIL, outs)
if (!(MII_MSR_LINKSTATUS & data))
{
*status = RT_FALSE; /* link down. */
}
else
{
*status = RT_TRUE; /* link up. */
}
outs:
return result;
}
用户驱动可以通过以下方法去获取在自己驱动中定义的每个PHY设备的实例,进而获取更多驱动所需要的信息,来更好地实现PHY驱动的兼容性。
c
struct h3_kszplib_dev *kszplib_dev;
RT_ASSERT(phy != RT_NULL);
kszplib_dev = rt_container_of(phy, struct h3_kszplib_dev, rt_phydev);
关于对PHY设备抽象的改进
通过上述的修改后,可以通过BSP_USING_PHY0这样的宏定义(在Kconfig中进行定义和选择),来实现驱动中对多个PHY的驱动支持和灵活配置。
c
#ifdef BSP_USING_PHY0
static struct rt_phy_ops h3_ksz0plib_ops =
{
.init = H3_KSZPLIB_PHY0INIT,
.read = h3_kszplib_read,
.write = h3_kszplib_write,
.loopback = h3_kszplib_loopback,
.get_link_status = h3_kszplib_linkstatus,
.get_link_speed_duplex = H3_KSZPLIB_PHY0LINKS,
};
static struct h3_kszplib_dev h3_kszdev0 =
{
.name = PHY0_DEVICE_NAME,
.phy_addr = PHY0_DEVICE_ADDRESS,
.rt_phydev =
{
.ops = &h3_ksz0plib_ops,
}
};
#endif // BSP_USING_PHY0
同样在PHY设备注册代码中,也可以采取非常灵活的方式,来实现对多个PHY设备的注册操作
c
int h3_kszplib_init(void)
{
rt_uint32_t table_sz = sizeof(h3_kszplib_devtable)/sizeof(uint32_t);
struct h3_kszplib_dev *kszplib_dev;
for (uint32_t i = 1; i < table_sz; i++)
{
kszplib_dev = h3_kszplib_devtable[i];
rt_hw_phy_register(&kszplib_dev->rt_phydev, kszplib_dev->name);
}
return RT_EOK;
}