On 05/19/2011 09:40 AM, Avi Kivity wrote:
On 05/19/2011 05:37 PM, Anthony Liguori wrote:
So.... do you do:
isa_register_region(ISABus *bus, MemoryRegion *mr, int priority)
{
chipset_register_region(bus->chipset, mr, priority + 1);
}
I don't really understand how you can fold everything into one table
and not allow devices to override their parents using priorities.
Think of how a window manager folds windows with priorities onto a flat
framebuffer.
You do a depth-first walk of the tree. For each child list, you iterate
it from the lowest to highest priority, allowing later subregions
override earlier subregions.
Okay, but this doesn't explain how you'll let RAM override the VGA
mapping since RAM is not represented in the same child list as VGA (RAM
is a child of the PMC whereas VGA is a child of ISA/PCI, both of which
are at least one level removed from the PMC).