[GSoC - x86_64] Using FreeBSD's UEFI loader for RTEMS static binaries

[Jan.Sommer at dlr.de]

> -----Original Message-----
> From: devel [mailto:devel-bounces at rtems.org] On Behalf Of Chris Johns
> Sent: Thursday, June 14, 2018 7:56 AM
> To: joel at rtems.org; Amaan Cheval
> Cc: RTEMS
> Subject: Re: [GSoC - x86_64] Using FreeBSD's UEFI loader for RTEMS static
> binaries

[...]
> >     >>
> >     -------------------------------------------------------------------------------------
> >     >>
> >     >> What I need input on:
> >     >> - Right now, we use the following RTEMS code for testing:
> >     >>
> >     >> int main() {
> >     >>   while(1) {}
> >     >> }
> >     >>
> >     >
> >     > It's not really an RTEMS code, it is a C program (ktest.c) compiled
> >     > with the RTEMS-flavored toolchain, right?
> >
> >     Yeah, for now that's right. I'm going to conduct the same gdb based
> >     debug-stepping style test for RTEMS setting boot_card as the entry
> >     point soon - for now, it crashes QEMU with:
> >
> >     qemu: fatal: Trying to execute code outside RAM or ROM at
> 0x00000000000b0000
> >
> >     RAX=00000000006004c0 RBX=00000000006003d8 RCX=0000000037f36000
> >     RDX=0000000000400000
> >     RSI=0000000004000000 RDI=0000000000000180 RBP=00000000006003d8
> >     RSP=000000003c589fb8
> >     ...
> >
> >     I see that it reaches that stage even from some code it ought not to
> >     be executing, so I'll look into what that may be about.
> 
> Hmm.
> 

I don't know if that is of any help, but when I was starting to use the i386-bsp with our build system I had a similar issue.
The reason was that I forgot to use the linker flags (-Wl,-Ttext,0x00100000) used in the RTEMS makefiles in our build setup.
Maybe something similar has to be done for x86_64 too in order to relocate the text section to a more sensible location?

[...]


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Jan Sommer
Telephone +49 531 295-2494 | Telefax 0531 295-2767 | jan.sommer at dlr.de
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