Add a new option, SKYEYE_WORKAROUNDS, which as the name suggests adds
workarounds for things skyeye doesn't simulate. Specifically :
- Use USART0 instead of DBGU as the console, make it not use DMA, and manually provoke an interrupt when we're done in the transmit function.
- Skyeye maintains an internal counter for clock, but apparently there's
no way to access it, so hack the timecounter code to return a value which
is increased at every clock interrupts. This is gross, but I didn't find a
better way to implement timecounters without hacking Skyeye to get the
counter value.
- Force the write-back of PTEs once we're done writing them, even if they
are supposed to be write-through. I don't know why I have to do that.
2e58b61962