Intel Ethernet i217: Difference between revisions

To start with, lets state some macro definitions that we are going to use in the code.

#define INTEL_VEND 0x8086 // Vendor ID for Intel

#define TSTA_LC (1 << 2) // Late Collision

#define LSTA_TU (1 << 3) // Transmit Underrun

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

Now we need to detect if the card has an EEPROM or not. The Qemu and Bochs emulate EEPROM, but the I217 and 82577LM do not. The following first method tries to read the status field of the EEPROM, the status field should contain the value 0x10, and based on the result the internal data member eerprom_exists. The second method performs a 2-bytes read operation from the EEPROM

bool E1000::detectEEProm()

{

}

The first thing you will need to do after detecting the BAR0 type and the existence of the EEPROM is to read the hardware MAC address of the NIC. The following method reads the hardware mac address based. If an EEPROM exists it will read it from the EEPROM else it will read it from address 0x5400 where it should be located in that case. It is very important to detect if an EEPROM exists or not prior to reading the MAC address.

bool E1000::readMACAddress()

return true;

}

Now, we need to configure the transmit and receive descriptor buffers, here are the implementation of the corresponding methods. The rxinit method is identical to the one I use for my e1000 driver. The difference is in txinit

void E1000::rxinit()

bool E1000::start ()