Intel Ethernet i217: Difference between revisions

Now lets define the data structures for the transmit and receive buffers

 

 

#define E1000_NUM_RX_DESC 32

} __attribute__((packed));

 

 

And finally some helper static methods for MMIO read/write operations and Ports I/O

 

 

class MMIOUtils

}

 

 

#ifndef PORTS_H_

#define PORTS_H_

 

 

 

== The Driver Class Header (Class Definition)==

 

 

class E1000 : public NetworkDriver

{

~E1000(); // Default Destructor

};

 

== How the Gears Move (Class methods implementation) ==

First of all we need to be able to send commands and read results from the NIC. It is important to detect the type of BAR0 and based on that the correct communication mechanism should be adopted. The following two methods encapsulate the read/write commands and uses MMIO or IO ports based on the value in BAR0 which is reflected in bar_type data member flag.

 

void E1000::writeCommand( uint16_t p_address, uint32_t p_value)

{

}

}

 

 

 

To enable interrupts

void E1000::enableInterrupt()

{

 

}

 

As we have defined most of the building blocks and the helper methods lets define the main methods of the class.

The constructor is responsible for fetching PCI related data and initialize the object internal state

 

E1000::E1000(PCIConfigHeader * p_pciConfigHeader) : NetworkDriver(p_pciConfigHeader)

{

eerprom_exists = false;

}

 

The start method basically detects the EEPROM, reads the MAC addresses, setup rx and tx buffers, register the interrupt handler, and enable NIC interrupts

 

Your interrupt handler should eventually call the fire method which handles the NIC's events

 

void E1000::fire (InterruptContext * p_interruptContext)

}

 

 

Finally we define the sendPacket method as follows

 

 

int E1000::sendPacket(const void * p_data, uint16_t p_len)

}

 

 

 

This is an example of how to instantiate an object of this class and startup you driver. I assume that you have scanned your PCI buses and loaded the found devices parameters into some data structures; in our example this is done by the PCIConfigManager class, which is outside the scope of this tutorial

 

 

pciConfigHeaderManager.initialize(); // Initialize the PCIConfigHeaderManager Object and scan PCI devices

}

 

 

== Summary and Wrap Up ==