[Request] Cisco c240 m5 bios mod with rebar

BIOS/UEFI Modding BIOS Modding Requests
1

Good afternoon gents,
I bought a cisco c240 m5 updated to the latest version of bios and all that. Everything runs great. Has 2xNVME + 2xM.2 + 24x12g sas connectors. Server screams the only issue I have is resizable bar. 4g decoding is enabled every check box on gpuz is good except rebar in bios. I have the cap file and was wondering if anyone could modify the bios to enable rebar. This is because im using Intel b50 pro in the server for transcode and some ai. SR-IOV is only allowed if rebar is enabled. I am willing to compensate anyone for there time in trying to get this to work. I have tried uefitool and some others with no luck. The bios I pulled from ucs-c240m5-huu-4.2.3p.iso and I have it at https://remote.jammersplace.com/bios/bios.cap. I know its AMI bios. I can get more info if you need. Pictures screens all that just let me know. Screenshots below.

2

I doubt this being possible on Intel® C621 series chipset.

4

I did see somewhere that someone got a r730 to have resizable bar. That is running the c610 chipset. I am hopeful.

5

Then go for it…
[Release] Resizable BAR BIOS EFI Module - BIOS/UEFI Modding / BIOS modules (PCI ROM, EFI and others) - Win-Raid Forum

6

I think you might need to pull the entire bios using a programmer like ch341a to be able to read the entire bios using the tools available here.

7

I’ll get one and see if I can pull the info.

8

Did you ever get anywhere with this? I have a C240M5 and would also like to get rebar enabled.

I couldn’t even get the Arc B50 to be recognized correctly.

Also, which is the correct bios on the HUU iso? I assume it’s one in the squashfs filesystem.

9

The user didn’t return for it.. and also it seems the bios.cap the user gave is not the complete bios or maybe it’s cisco’s own capsule? If you could dump the whole bios contents, maybe we could help

10

Well, I can get access to the Cisco stuff if needed. I used the .63 version HUU to update the firmware on my unit, and it updated the CIMC, onboard controllers and the BIOS which gave me the ability to turn on >4G decoding… but obviously there’s no option for rebar.

The latest huu’s I can find are here: Index of /garbage

I’m not sure which bios file is the right one, but if you hexedit the “bios.cap” that’s in the squashfs blob it seems to reference a CIMC update. Of course, it might be a multipart cap that has >1 update in it, I don’t know. I’m no expert when it comes to bios/uefi hacking.

11

I managed to dig up my usb eeprom kit (based on the same one listed earlier on the thread).

I’ll grab a copy of the ROM during my next scheduled change management window :slight_smile: (whenever I feel like cracking open the damn thing).

1 Like