Function ProcessIOPTag

pcsx2/Sif0.cpp:116–144

Read Fifo into an iop tag, and transfer it to hw_dma9. And presumably process it.

// Read Fifo into an iop tag, and transfer it to hw_dma9. And presumably process it.
static __fi bool ProcessIOPTag()
{
	// Process DMA tag at hw_dma9.tadr
	sif0.iop.data = *(sifData *)iopPhysMem(hw_dma9.tadr);
	sif0.iop.data.words = sif0.iop.data.words;

	// send the EE's side of the DMAtag.  The tag is only 64 bits, with the upper 64 bits being the next IOP tag
	// ignored by the EE, however required for alignment and used as junk data in small packets.
	sif0.fifo.write((u32*)iopPhysMem(hw_dma9.tadr + 8), 4);

	// I know we just sent 1QW, because of the size of the EE read, but only 64bits was valid
	// so we advance by 64bits after the EE tag to get the next IOP tag.
	hw_dma9.tadr += 16;

	// We're only copying the first 24 bits.  Bits 30 and 31 (checked below) are Stop/IRQ bits.
	hw_dma9.madr = sif0data & 0xFFFFFF;
	if (sif0words > 0xFFFFF) DevCon.Warning("SIF0 Overrun %x", sif0words);
	//Maximum transfer amount 1mb-16 also masking out top part which is a "Mode" cache stuff, we don't care :)
	sif0.iop.counter = sif0words & 0xFFFFF;

	// Save the number of words we need to write to make up 1QW from this packet. (See "Junk data writing" in Sif.h)
	sif0.iop.writeJunk = (sif0.iop.counter & 0x3) ? (4 - sif0.iop.counter & 0x3) : 0;

	// IOP tags have an IRQ bit and an End of Transfer bit:
	if (sif0tag.IRQ  || (sif0tag.ID & 4)) sif0.iop.end = true;
	SIF_LOG("SIF0 IOP Tag: madr=%lx, tadr=%lx, counter=%lx (%08X_%08X) Junk %d", hw_dma9.madr, hw_dma9.tadr, sif0.iop.counter, sif0words, sif0data, sif0.iop.writeJunk);

	return true;
}

// Stop transferring ee, and signal an interrupt.
static __fi void EndEE()