BIOS n large PCI window

[lettuce]

Server: Dell R610, Intel 5500 chipset, 6GB RAM.

A PCI device in my server requires a large memory (>2GB) and BIOS seems to hang trying allocate such large memory. It fails to output anything to the screen or the serial port in this mode. I'm speculating that the BIOS is unable to fit this 2GB PCI window below the 4GB limit and is hung. I'm assuming that if there is anyway to tell BIOS not to worry about being compatible with a 32-bit OS, then it will be able to allocate the requested large PCI memory. I can't find any such setting in my BIOS. Any suggestions?

 

[VirtualLarry]

There are no PCI devices that allocate memory regions above 4GB, for 32-bit PCI cards. All HW I/O is mapped below 4GB.

 

[lettuce]

Not sure what you mean by 32-bit PCI cards. The PCI card that I'm using supports 64-bit bars and I'm configuring it that way. The BIOS is able to allocate upto 1GB for PCI space for this device; but as soon as I request 2GB PCI space; it hangs. Oddly enough if I use 2 different 64-bit bars each requesting 1GB each, BIOS can handle it. In both cases (1GB with 1 bar and 2 bars with 1GB each), allocated address range is below 4GB. To be more specific, first window address range is 1-2GB and the second window (when requested with the 2nd BAR) is 2-3GB.

However, BIOS just can't seem to be able to allocate a single 2GB memory window with one bar. In my application, I need at least 4GB of total PCI space. Again, the chipset supports 64-bit operations and the OS that gets loaded after the BIOS completes is 64-bit as well.

thanks,

There are no PCI devices that allocate memory regions above 4GB, for 32-bit PCI cards. All HW I/O is mapped below 4GB.