On Mon, Feb 07, 2011 at 07:17:52PM +0000, Prasad Joshi wrote:
Hello,
I am working on QEMU to pass-through a graphics device. I noticed few problems with PCI enumeration hence I compiled SeaBIOS with more debug information.
The PCI enumeration problem seems to be related to BUILS_PCIMEM_SIZE. I keep on getting the error 'increase BUILD_PCIMEM_SIZE and recompile'. This happens when BIOS tries to allocate 128MB for one of the BAR. The code seems to be printing the correct error as, the 128MB naturally aligned memory request can not be satisfied. No problem with this.
As I notice on my host machine the same case happens, but host BIOS seems to be allocating 128MB memory from some other region (c0000000-c7ffffff)
[...]
Can SeaBIOS do the same thing? or to put in other words Can SeaBIOS allocate memory from some other region instead of fixed f0000000 to (0xfec00000-1)?
It should be possible to alter BUILD_PCIMEM_START in src/config.h. The reason it is at 0xf0000000 is because regular memory can go up to 0xe0000000, and the bochs vga bios had soe dependency on the address space at 0xe0000000 - though this may no longer be the case.
-Kevin