Re: [Qemu-devel] PCI: Memory mapped / ROM resources

[Gianni Tedesco <gianni@scaramanga.co.uk>]

On Wed, 2004-05-26 at 23:50, Fabrice Bellard wrote:
> Gianni Tedesco wrote:
> 
> > I'm adding a host PCI proxy layer that works under Linux, ie: make host
> > PCI devices appear within the emulator. Similar to 'pcidev' on bochs,
> > but without a custom kernel module, and some minor performance
> > enhancements. I ought to have a patch ready by tomorrow evening.
> 
> Interesting. How do you redirect irqs ?

A small patch to /proc/pci which adds an ioctl PCIIOC_SIGIRQ which
allows for the kernel to send (user defined) rtsignals when IRQs are
recieved. It may be interesting to X folk and the like, so with some
cleanups maybe they'll merge it, who knows.

> > PS. I am using mmap() on /proc/pci/bus/XX/YY.Z nodes to map PCI
> > registers, probably there is a nice way to allow the code generator to
> > generate accesses directly on to these vmas? It's probably not that much
> > of a win in any case, but interesting.
> 
> You'd better defines memory access callbacks. It could be possible to 
> define RAM memory areas for which the access is optimised internally by 
> the CPU core, but currently they must stay in the phys_ram_base array.

It will be OK if i pass mmap a start address and map right over some
regions in phys_ram_base?

-- 
// Gianni Tedesco (gianni at scaramanga dot co dot uk)
lynx --source www.scaramanga.co.uk/scaramanga.asc | gpg --import
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