mips and libgloss/mips/tx39 simulator questions

mips and libgloss/mips/tx39 simulator questions

[Joel Sherrill]

I think I am looking for some very basic setup/startup
user instructions. :)  Target is mips64orion-rtems.

I am trying to put together a simple RTEMS BSP based 
on the tx39 code in libgloss.  How is the simulator
invoked to make these executables run?  I have worked
my way up to this based on various net resources:

target sim --board=jmr3904pal \
  --memory-region 0xffff8000,0x900 \
  --memory-region 0xffffe000,0x4 \
  --memory-region 0xb2100000,0x4 \
  --memory-region=0x8800000,0x1000000

load produces the following output:

Loading section .text, size 0x12fe0 vma 0x8800000
Loading section .reginfo, size 0x18 vma 0x8812fe0
Loading section .rdata, size 0xfc0 vma 0x8813000
Loading section .data, size 0x6b0 vma 0x8813fc0
Loading section .lit8, size 0x20 vma 0x8814670
Loading section .sdata, size 0x90 vma 0x8814690
Start address 0x8800004
Transfer rate: 669888 bits in <1 sec.
(gdb) r
Starting program:
/usr1/rtems/build/build-mips-rtems/mips-rtems/jmr3904/tests/hello.exe 
mips-core: 8 byte write to unmapped address 0x80009ff8 at 0x0

Advice would be greatly appreciated.  

Also any comments on using what cpu models the simulator supports
would be welcome.

Thanks. 


-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel@OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985

Re: mips and libgloss/mips/tx39 simulator questions

[Frank Ch. Eigler]

Joel Sherrill <joel.sherrill@OARcorp.com> writes:

: [...]
: I am trying to put together a simple RTEMS BSP based 
: on the tx39 code in libgloss.  [...]
: target sim --board=jmr3904pal \
:   --memory-region 0xffff8000,0x900 \
:   --memory-region 0xffffe000,0x4 \
:   --memory-region 0xb2100000,0x4 \
:   --memory-region=0x8800000,0x1000000
: [...]
: /usr1/rtems/build/build-mips-rtems/mips-rtems/jmr3904/tests/hello.exe 
: mips-core: 8 byte write to unmapped address 0x80009ff8 at 0x0

Well, what memory region is supposed to sit at 0x80009ff8?  It's hard
to help without some idea of what your BSP code assumes about the
target board; what the code was trying to do at the time (--trace).


: Also any comments on using what cpu models the simulator supports
: would be welcome.

See the "*cpu:" tags in the src/mips/*.igen files, the configure.in
target filtering lines, and perhaps some TARGET-run command-line
option.


- FChE

Re: mips and libgloss/mips/tx39 simulator questions

[Joel Sherrill]

"Frank Ch. Eigler" wrote:
> 
> Joel Sherrill <joel.sherrill@OARcorp.com> writes:
> 
> : [...]
> : I am trying to put together a simple RTEMS BSP based
> : on the tx39 code in libgloss.  [...]
> : target sim --board=jmr3904pal \
> :   --memory-region 0xffff8000,0x900 \
> :   --memory-region 0xffffe000,0x4 \
> :   --memory-region 0xb2100000,0x4 \
> :   --memory-region=0x8800000,0x1000000
> : [...]
> : /usr1/rtems/build/build-mips-rtems/mips-rtems/jmr3904/tests/hello.exe
> : mips-core: 8 byte write to unmapped address 0x80009ff8 at 0x0
> 
> Well, what memory region is supposed to sit at 0x80009ff8?  It's hard
> to help without some idea of what your BSP code assumes about the
> target board; what the code was trying to do at the time (--trace).

I think that's my problem.  I am trying to be blind about the "board."
I simply want to use the tx39 simulator in gdb as a test target for
RTEMS.  I did not really care what kind of mips3 it was.  I just liked
the fact it had real peripherals.  I used the support code in libgloss
as "reference material" making as few changes as possible to cast
it into the form of an RTEMS BSP.  Now I have a linked RTEMS hello.exe
that seems to run on the simulator until it tries to do IO.  Then it
is in a loop waiting toa status bit in the SIO controller to change but
I believe I did not tell gdb the right stuff to enable it.

What is the proper magic to run that code?

What I am trying to match is (I think) equivalent to what is called
tx39-sim in dejagnu.

> : Also any comments on using what cpu models the simulator supports
> : would be welcome.
> 
> See the "*cpu:" tags in the src/mips/*.igen files, the configure.in
> target filtering lines, and perhaps some TARGET-run command-line
> option.

Thanks.  That I can do. :)

> - FChE

--joel