Hello Stephan,

I have had the same issue with my platform and had the OS stuck for

different reasons. These are the things you can do to see if you are

making any progress:

1. I had the OS stuck at the same place you are stuck because of the

PROGRESS CODE reports and the DEBUG logs sending data through the

serial port. Try to disable these logs and see if you can get any

further.

The reason is that the hardware should completely be within the OS's

possession at this point, so calls to the serial port at further

stages, such as the RunTime Stage, may crash the processor.

2. Try to check the memory map passed from SBL to EDK2 as a HOB is

completely correct.

Best,

Alireza

On Wed, May 14, 2025, 2:50 PM Stepan via groups.io <radio-fan=mail.ru@groups.io> wrote:

Hello EDKII community,

We build ELF UefiPayload for custom Alder Lake S board (we load UEFI by SBL). This payload boots GRUB2 (and another efi programs, such as memtest) successfully. We tried load Win10, but we didn't get boot visibility. After the load attempt, the following messages were added to the log.
XhcClearBiosOwnership: called to clear BIOS ownership
SmmInstallProtocolInterface: 296EB418-C4C8-4E05-AB59-39E8AF56F00A 0
CpuDxe: 5-Level Paging = 0
Surprisingly, the Win7 starts booting in safe mode but stops at one of the drivers (This also happens on the factory bios. Most likely, Win7 does not support our hardware).

Ubuntu booting is also interrupted before first kernel printk. We build kernel for debugging, but kernel debugging starts too late. I attach logs of loading by EDKII (fail) and default loading by the factory bios (only kernel messages).

We don't understand how to deal with this situation. Can anyone help/suggest ?

P.S. While I was writing, I thought what if I put a breakpoint on the XhcClearBiosOwnership function in EDK II and check it out.