I want to try the suggestion from the previous page regarding changing NVRAM settings with SCEWIN. It seems possible to enable Above 4G decoding in the NVRAM settings, but I
cannot write back to NVRAMÂ with SCEWIN. It seems the NVRAM is locked. Does anyone know how to unlock it so I can try?
I have tried FalseClock's EFI nvram variable modifier, but I am not sure I used the right offset for the variables I want to modify. From the SCEWIN dump, I think I want to change to these settings:
Setup Question = MMIOHBase
Token =192 // Do NOT change this line
Offset =F76
Width =04
BIOS Default =[00]56T
Options =*[00]56T // Move "*" to the desired Option
[01]40T
[02]24T
Setup Question = MMIO High Size
Token =193 // Do NOT change this line
Offset =F7A
Width =04
BIOS Default =[03]1024G
Options =[00]256G // Move "*" to the desired Option
[01]128G
[02]512G
*[03]1024G
Setup Question = Above 4G Decoding
Token =330 // Do NOT change this line
Offset =227
Width =01
BIOS Default =[01]Enabled
Options =[00]Disabled // Move "*" to the desired Option
*[01]Enabled
For example I tried:
setup_var 0x227 0x01
to enable above 4G pcie / high bar / 64bit pcie address decoding on the x99s.
I see "error: offset is out of range" from FalseClock's shell.
My motivation is I want to try a xeon phi or K80 in this board (k40 works out of the box)
I guess the problem is an smi handler from MSI that blocks writing nvram. I found a suggestion
here to patch the BIOS for this: but it seems too old and no longer works