[coreboot] Help required to boot DUET (Seabios floppy mechanism)

Scott Duplichan spambucket at notabs.org
Wed Nov 6 00:28:09 CET 2013

Anthony Ross wrote:

]Hello Coreboot Folks,
]Well Thanks for the suggestions. It seems that  DUET boots but now a major problem has ]cropped up. It freezes at the main
DUET-BIOS page not allowing to perform any further ]operations, like booting a HDD image or fingering around the EFI BIOS options.
Similarly ]If I had the .lzma to the cbfs file name I face the same problem like earlier so having ]it as myfloppy.img makes it take
]Any further Ideas about these problems.....

For your freeze problem, how are you debugging? The usual way
is to enable and capture debug messages written to a serial
port. I believe the standard Duet settings make it write
debugging messages to a serial port at 3F8 (115200,8,N,1).
Because halt for assert is enabled by default on Duet, an 
assert is the most likely reason for a freeze. The assert
will log details to the serial port.

If your hardware doesn't have a serial port, you can use
an emulator such as simnow or qemu. A good thing about
Duet is that it is generic and in theory can run on 
different systems without porting. If I remember correctly,
the current Duet project can boot to the UEFI shell and
menu system on AMD simnow using the Solo board model.

I am working on a project to allow Duet to run as a
coreboot payload, and to fix the major Duet problems.
It will also continue to support bootable image form.
It may take me a few weeks to reach the goal of booting
operating systems in UEFI mode on real hardware though.


On Sat, Oct 26, 2013 at 8:01 PM, Kevin O'Connor <kevin at koconnor.net> wrote:
On Thu, Oct 24, 2013 at 12:17:33AM -0500, Scott Duplichan wrote:
> Scott Duplichan wrote:
> <..snip..>
> ]I have no experience with making SeaBIOS boot an embedded floppy
> ]image. I may be able to give this a try, but I would have to first overcome
> ]Windows build problems that have crept into both SeaBIOS and coreboot.
> I tested the SeaBIOS virtual floppy boot with EDK2 Duet and it worked
> for me. I tested with the ASRock e350M1 project. Here is the cbfstool
> output:
Thanks for confirming.

> scott at p67-2600k /D/coreboot/win-build-env-011/coreboot/build
> $ cbfstool.exe coreboot.rom print
> coreboot.rom: zd kB, bootblocksize 4096, romsize 1008, offset 0x400000
> alignment: 0 bytes
> Name                           Offset     Type         Size
> cmos_layout.bin                0x0        cmos_layout  1776
> pci1002,9802.rom               0x740      optionrom    57856
> fallback/romstage              0xe980     stage        345432
> fallback/coreboot_ram          0x62f40    stage        203312
> fallback/payload               0x949c0    payload      53738
> config                         0xa1c00    raw          3831
> (empty)                        0xa2b40    null         3526744
> scott at p67-2600k /D/coreboot/win-build-env-011/coreboot/build
> $ cbfstool.exe coreboot.rom add -f /d/duetfloppy.img -n floppyimg/duetfloppy.img -t raw
FYI, it's also possible to add an lzma compressed image (make sure the
cbfs filename ends in ".lzma" then).


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