RTL8139: Difference between revisions

this should essentially *power on* the device.

 

outportb( ioaddr + 0x52, 0x0);

 

==== Software Reset! ====

initialization procedure.

 

outportb( ioaddr + 0x37, 0x10);

while( (inb(ioaddr + 0x37) & 0x10) != 0) { }

 

==== Init Receive buffer ====

that variables memory location to the RBSTART register (0x30).

 

//ioaddr is obtained from PCI configuration

outportd(ioaddr + 0x30, (uintptr_t)rx_buffer); // send uint32_t memory location to RBSTART (0x30)

 

Note that 'rx_buffer' needs to be a pointer to a '''physical address'''. In this case a size of 8192 + 16 (8K + 16 bytes) is recommended, see below.

a TOK or ROK IRQ happens, it actually will go through and fire up an IRQ.

 

outportw(ioaddr + 0x3C, 0x0005); // Sets the TOK and ROK bits high

 

=== Configuring receive buffer (RCR) ===

You can also tell the size of your RX buffer here, however if you use a 8k + 16 buffer as described before, writing zeroes is enough. To use the WRAP=1 bit, an 8K buffer must in fact be 8k+16+1500 bytes.

 

outportl(ioaddr + 0x44, 0xf | (1 << 7)); // (1 << 7) is the WRAP bit, 0xf is AB+AM+APM+AAP

 

=== Enable Receive and Transmitter ===

Once this is completed, then the card will start allowing packets in and/or out.

 

outportb(ioaddr + 0x37, 0x0C); // Sets the RE and TE bits high

 

=== Transmitting Packets ===

When you handle an interrupt, you ''have'' to write the bit corresponding to the interrupt to reset it. The datasheet says reading the register is enough to reset the buffer to zero and writing has no effect. ''This is not the case on QEMU'', and probably on some/most hardware too.

 

 

For example, this is tested and works on QEmu:

 

void rtl8139_handler(uint8_t isr, uint64_t error, uint64_t irq) {

uint16_t status = inw(io_base + 0x3e);

}

}

 

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