From /sys/src/cmd/aux/vga/i81x.c:

	/*	<<TODO>>
		i830 LCD Controller, at i81x->mmio+0x60000
		i81x->lcd[0]: Horizontal Total Reg.		0x60000
		i81x->lcd[1]: Horizontal Blanking Reg.	0x60004
		i81x->lcd[2]: Horizontal Sync Reg. 		0x60008
		i81x->lcd[3]: Vertical Total Reg.		0x6000c
		i81x->lcd[4]: Vertical Blanking Reg.		0x60010
		i81x->lcd[5]: Vertical Sync Reg. 		0x60014
		i81x->lcd[6]: Pixel Pipeline A Sequencer Register Control(SRC,0~7)	0x6001c
		i81x->lcd[7]: BCLRPAT_A	0x60020
	         i81x->lcd[8]: 0
	*/

This matches the LCD registers in the specsheet, but these are never
initialized.  It looks like the LCD part of the driver was simply
never finished...

I'm mostly just putting this here for posterity.  This won't get fixed
if I just sit here and whine about it, and I intend to do something
about that.