[U-Boot] x86: EFI: boot fails at exit_boot_services - Was: Stuck trying to build a non-qemu EFI payload

[Stoppa, Igor]

Hi Simon,
thanks for helping, please find my reply below.

On 21 August 2015 at 23:51, Simon Glass <sjg at chromium.org> wrote:

> Note that once you call exit_boot_services you will not be able to use
> the console. Be careful here - the board may appear to hang but
> actually it is broken by you trying to output to the console.

Yes, I had realised it, but it seemed - on qemu - that it would still
work to call "putc", after the code:

> map.version = version;
> map.desc_size = desc_size;
> add_entry_addr(priv, EFIET_MEMORY_MAP, &map, sizeof(map), desc, size);
> add_entry_addr(priv, EFIET_END, NULL, 0, 0, 0);

But maybe I was just "lucky" and it worked even if it was not supposed to.
For example, maybe it was using memory pages that had already been freed.

However, after your reply, I re-cloned the x86 branch, just to be sure
I would be starting from a clean slate, and re-did the configuration
from scratch, without adding any traces.

The result is that stub reaches the call "jump_to_uboot", so it seems
that there are no problems there.

The issues are to be found in the payload (as expected, since I'm
using the qemu defconfig).

Trying the QEMU image on my Haswell test device, I see it rebooting.

Since I do not have means to obtain a serial console (please see
footer note), I resorted to using a "while(1);" to identify the point
where the reboot happens, by turning the reboot into a hang.

The location where the reboot is triggered is in:

 common/board_f.c: board_init_f_mem @
1048:  memset(gd_ptr, '\0', sizeof(*gd));

I do not know the value of the pointer, but it seems that it is
incorrect and writing to this address causes a reset.

I wonder if this is because I'm still using the device tree for the
machine emulated by QEMU and if I should build one for my specific
Haswell NUC.

Btw, the EFI bios offers the option of printing the EFI device tree.
Is it the same used by U-Boot, so that I could use this information to
create the Device Tree file?

-- 
thanks, igor