[lkml]   [2011]   [Aug]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 1/2] x86, ioapic: Reserve only 128 bytes for IOAPICs
On 08/25/2011 06:41 PM, H. Peter Anvin wrote:
> On 08/25/2011 05:17 PM, Bjorn Helgaas wrote:
>> If the OS allocated the next 128 bytes to another device, it sounds
>> like it would cause a conflict on Intel boxes. This must be an area
>> that differs between vendors. I haven't seen a spec that mentions 256
>> bytes as the required minimum MMIO size for IOAPICs, and apparently
>> the AMD IOAPIC decodes 240 bytes or fewer.
> For what it's worth, it's probably a bad idea on x86 for the OS to
> allocate addresses in the 0xFExxxxxx range...
for system with more than one ioapic controllers, could have ioapic address rather low.
and those address are allocated to some pci devices BAR by BIOS.


 \ /
  Last update: 2011-08-26 08:21    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean