Messages in this thread |  | | From | "H. Peter Anvin" <> | Subject | Re: VGA PCI IO port reservations | Date | 17 Nov 2000 14:02:00 -0800 |
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Followup to: <Pine.LNX.4.10.10011172134510.27177-100000@sphinx.mythic-beasts.com> By author: Matthew Kirkwood <matthew@hairy.beasts.org> In newsgroup: linux.dev.kernel > > On Fri, 17 Nov 2000, Russell King wrote: > > > Therefore, it should be reserved independent of whether we have the > > driver loaded/in kernel or not. > > Is this not an argument for a more flexible resource allocation > API? One offering both: > > res = allocate_resource(restype, dev, RES_ALLOC_UNUSED, region); > > and > > res = allocate_resource(restype, dev_ RES_ALLOC_HW, region); >
One way to do this is to treat PCI IO and ISA IO as two separate address spaces. The PCI IO address space is a 14-bit address space (bits 9:8 are always zero) ranging from 0x1000 to 0xFCFF. ISA IO is a 10-bit space (bits 15:10 are available for the card to use) ranging from 0x100 to 0x3FF.
VGA cards may be PCI and AGP, but still have allocations in the ISA range.
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