About 2 months ago I discovered that it is supported by coreboot so I thought it would be fun to experiment with it.
Well, welcome!
2)
I then decided to try out Windows XP but the Installation would stop with STOP: 0xA5 (0x11, 0x8, ... .. ., .... ).
I could not figure it out...
Then I used a usb pen with "Active Boot Disk 9.4" in it, based on WindowsPE / Windows7.
For that I got STOP: 0xA5 (0x1000, 0x0, 0xFFFFFFF0, 0x400000) and that actually provided a clue.
Stop 0xa5 codes are under documented by Microsoft, but we collected whatever we could find about them at
https://coreboot.org/ACPI#STOP_0xa5 (it helped to attach windbg to a crashing Windows install that came with debug symbols).
Your error is listed in our collection: "Parameter1 == 0x00001000 means that some memory resource is claimed by ACPI that, according to memory tables, belongs to the OS. Parameter3 is the start address, Parameter4 is the length of the range".
Now, "0xFFFFFFF0, 0x400000" looks _very_ odd. 0xFFFFFFF0 is the 16bit cpu entry vector, and the size given doesn't really fit that, and there isn't really any other purpose to those 16 bytes, while it's also odd to reserve 4MB-16bytes above 4GB to anything.
I searched in the ACPI tables and found this in the x4x.asl file
...
OperationRegion (GFRG, SystemMemory, And (BAR0, 0xfffffffffffffff0), 0x400000)
Note the And(), so this would give you these values only if BAR0 is 0xffffffffffffffff.
The best approach may be to boot into Linux (which doesn't fail that hard, right?) and dump ACPI tables there so we can see what's going on (as some parts are generated at runtime, so it's not enough to look at the source code only).
If you put that stuff up somewhere, I'm sure that there will be folks interested to look into the issue (I am for sure).
5) None of the secondary payloads coreinfo, nvramcui and Memtest86+ worked for me.
I managed to get Memtest86+ working by selecting the "Master" version but did not investigate any further.
There's a known issue between memtest's stable version and our toolchain. Since master works for you, that seems good enough.
As for the others, how do they fail for you?
6) I tried to follow the "coreboot Overview" in https://www.coreboot.org/Developer_Manual but found it difficult, the
crt0_romcc_epilogue.inc for example does net exist in the source tree. Is there any other updated overview somewhere else?
I hope it's ok to report issues to the mailing list like this, apologies for the long email.
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