cross debugging r3912 cpu with gdb

cross debugging r3912 cpu with gdb

[Mark and Janice Juszczec]

Hi folks

I'm trying to track down a SIGSEGV generated by kaffe on the Helio pda.  It 
uses a  Phillips R3912 cpu.

The gdb 6.0 docs say configure as follows:  configure 
--target=mips-idt-ecoff.  I did and mips shows up as an available target.

Unfortunately, when I try to connect to the pda via a USB serial connection, 
I get:

(gdb) set debug remote 2
(gdb) target mips /dev/ttyUSB0
Expected "<IDT>", got "": FAIL
Expected "<IDT>", got "": FAIL
Expected "<IDT>", got "": FAIL
Failed to initialize.
Ending remote MIPS debugging.
You can't do that without a process to debug

Further research shows there is supposed to be a target named r3900.  It 
doesn't show up under my available targets and

(gdb) target r3900 /dev/ttyUSB0

gives and error saying there is no target named r3900.

Can anyone out there give me advice about gdb and mips cross debugging?

Mark

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Re: cross debugging r3912 cpu with gdb

[Daniel Jacobowitz]

On Sun, Dec 07, 2003 at 10:28:33PM +0000, Mark and Janice Juszczec wrote:
> 
> Hi folks
> 
> I'm trying to track down a SIGSEGV generated by kaffe on the Helio pda.  It 
> uses a  Phillips R3912 cpu.

You left out lots of details.  What operating system is the r3900
running?  From the list name, I assume it's Linux/MIPS.  So why did you
configure for mips-idt-ecoff?

If you're using gdbserver, then you want target=mips-linux and "target
remote", not "target mips".

> 
> The gdb 6.0 docs say configure as follows:  configure 
> --target=mips-idt-ecoff.  I did and mips shows up as an available target.
> 
> Unfortunately, when I try to connect to the pda via a USB serial 
> connection, I get:
> 
> (gdb) set debug remote 2
> (gdb) target mips /dev/ttyUSB0
> Expected "<IDT>", got "": FAIL
> Expected "<IDT>", got "": FAIL
> Expected "<IDT>", got "": FAIL
> Failed to initialize.
> Ending remote MIPS debugging.
> You can't do that without a process to debug
> 
> Further research shows there is supposed to be a target named r3900.  It 
> doesn't show up under my available targets and
> 
> (gdb) target r3900 /dev/ttyUSB0
> 
> gives and error saying there is no target named r3900.
> 
> Can anyone out there give me advice about gdb and mips cross debugging?
> 
> Mark
> 
> _________________________________________________________________
> Shop online for kids? toys by age group, price range, and toy category at 
> MSN Shopping. No waiting for a clerk to help you! http://shopping.msn.com
> 
> 
> 

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: cross debugging r3912 cpu with gdb

[Mark and Janice Juszczec]

Daniel

you wrote:
>
>You left out lots of details.
>

  Oops.  My bad.

>What operating system is the r3900 running?

  Yes its linux.  kernel v2.4.0-test1-acc22

>From the list name, I assume it's Linux/MIPS.  So why did you configure for 
>mips-idt-ecoff?
>
  Hmmmmm.  Good question.  The gdb docs say I have to if I want to use the 
MIPS remote debugging protocol.

  I did try --target=mipsel-elf-linux and --target-mipsel-linux.  I got the 
following targets:

(gdb) help target
Connect to a target machine or process.
The first argument is the type or protocol of the target machine.
Remaining arguments are interpreted by the target protocol.  For more
information on the arguments for a particular protocol, type
`help target ' followed by the protocol name.

List of target subcommands:

target async -- Use a remote computer via a serial line
target cisco -- Use a remote machine via TCP
target core -- Use a core file as a target
target exec -- Use an executable file as a target
target extended-async -- Use a remote computer via a serial line
target extended-remote -- Use a remote computer via a serial line
target remote -- Use a remote computer via a serial line
target sim -- Use the compiled-in simulator

  I figured mips should show up, so I guessed they were incorrect.  Even so, 
I tried connecting with both and got the same results:

(gdb) target async /dev/ttyUSB0
Remote debugging using /dev/ttyUSB0
Sending packet: $Hc-1#09...Sending packet: $Hc-1#09...Sending packet: 
$Hc-1#09...Sending packet: $Hc-1#09...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Sending packet: $qC#b4...Sending packet: $qC#b4...Sending packet: 
$qC#b4...Sending packet: $qC#b4...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Sending packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Sending 
packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Couldn't establish connection to remote target
Malformed response to offset query, timeout

  Any idea what that all means?

>If you're using gdbserver, then you want target=mips-linux and "target
>remote", not "target mips".
>

  I'm not using gdbserver.  It won't fit on my pda if I include kaffe and 
its associated files.

  Mark

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Re: cross debugging r3912 cpu with gdb

[Mark and Janice Juszczec]

Daniel

you wrote:
>
>You left out lots of details.
>

  Oops.  My bad.

>What operating system is the r3900 running?

  Yes its linux.  kernel v2.4.0-test1-acc22

From the list name, I assume it's Linux/MIPS.  So why did you configure for 
>mips-idt-ecoff?
>
  Hmmmmm.  Good question.  The gdb docs say I have to if I want to use the 
MIPS remote debugging protocol.

  I did try --target=mipsel-elf-linux and --target-mipsel-linux.  I got the 
following targets:

(gdb) help target
Connect to a target machine or process.
The first argument is the type or protocol of the target machine.
Remaining arguments are interpreted by the target protocol.  For more
information on the arguments for a particular protocol, type
`help target ' followed by the protocol name.

List of target subcommands:

target async -- Use a remote computer via a serial line
target cisco -- Use a remote machine via TCP
target core -- Use a core file as a target
target exec -- Use an executable file as a target
target extended-async -- Use a remote computer via a serial line
target extended-remote -- Use a remote computer via a serial line
target remote -- Use a remote computer via a serial line
target sim -- Use the compiled-in simulator

  I figured mips should show up, so I guessed they were incorrect.  Even so, 
I tried connecting with both and got the same results:

(gdb) target async /dev/ttyUSB0
Remote debugging using /dev/ttyUSB0
Sending packet: $Hc-1#09...Sending packet: $Hc-1#09...Sending packet: 
$Hc-1#09...Sending packet: $Hc-1#09...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Sending packet: $qC#b4...Sending packet: $qC#b4...Sending packet: 
$qC#b4...Sending packet: $qC#b4...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Sending packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Sending 
packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Timed out.
Timed out.
Timed out.
Ignoring packet error, continuing...
Couldn't establish connection to remote target
Malformed response to offset query, timeout

  Any idea what that all means?

>If you're using gdbserver, then you want target=mips-linux and "target
>remote", not "target mips".
>

  I'm not using gdbserver.  It won't fit on my pda if I include kaffe and 
its associated files.

  Mark

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Re: cross debugging r3912 cpu with gdb

[Daniel Jacobowitz]

On Mon, Dec 08, 2003 at 12:02:14AM +0000, Mark and Janice Juszczec wrote:
> 
> Daniel
> 
> you wrote:
> >
> >You left out lots of details.
> >
> 
>  Oops.  My bad.
> 
> >What operating system is the r3900 running?
> 
>  Yes its linux.  kernel v2.4.0-test1-acc22
> 
> >From the list name, I assume it's Linux/MIPS.  So why did you configure 
> >for mips-idt-ecoff?
> >
>  Hmmmmm.  Good question.  The gdb docs say I have to if I want to use the 
> MIPS remote debugging protocol.
> 
>  I did try --target=mipsel-elf-linux and --target-mipsel-linux.  I got the 
> following targets:
> 
> (gdb) help target
> Connect to a target machine or process.
> The first argument is the type or protocol of the target machine.
> Remaining arguments are interpreted by the target protocol.  For more
> information on the arguments for a particular protocol, type
> `help target ' followed by the protocol name.
> 
> List of target subcommands:
> 
> target async -- Use a remote computer via a serial line
> target cisco -- Use a remote machine via TCP
> target core -- Use a core file as a target
> target exec -- Use an executable file as a target
> target extended-async -- Use a remote computer via a serial line
> target extended-remote -- Use a remote computer via a serial line
> target remote -- Use a remote computer via a serial line
> target sim -- Use the compiled-in simulator
> 
>  I figured mips should show up, so I guessed they were incorrect.  Even so, 
> I tried connecting with both and got the same results:
> 
> (gdb) target async /dev/ttyUSB0
> Remote debugging using /dev/ttyUSB0
> Sending packet: $Hc-1#09...Sending packet: $Hc-1#09...Sending packet: 
> $Hc-1#09...Sending packet: $Hc-1#09...Timed out.
> Timed out.
> Timed out.
> Ignoring packet error, continuing...
> Sending packet: $qC#b4...Sending packet: $qC#b4...Sending packet: 
> $qC#b4...Sending packet: $qC#b4...Timed out.
> Timed out.
> Timed out.
> Ignoring packet error, continuing...
> Sending packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Sending 
> packet: $qOffsets#4b...Sending packet: $qOffsets#4b...Timed out.
> Timed out.
> Timed out.
> Ignoring packet error, continuing...
> Couldn't establish connection to remote target
> Malformed response to offset query, timeout
> 
>  Any idea what that all means?
> 
> >If you're using gdbserver, then you want target=mips-linux and "target
> >remote", not "target mips".
> >
> 
>  I'm not using gdbserver.  It won't fit on my pda if I include kaffe and 
> its associated files.

Then what ARE you using on the target?

You have to connect to some particular debug stub.  That determines
what protocol to use.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: cross debugging r3912 cpu with gdb

[Mark and Janice Juszczec]

Daniel

>
>Then what ARE you using on the target?
>

I have a kernel, busybox (for init and sh) and kaffe+associated files.  
These have all been cross compiled from i386 for mipsel-linux using gcc 
(2.95 or 3.0).

>You have to connect to some particular debug stub.  That determines
>what protocol to use.
>


I wanted to test starting the whole thing up and connecting with gdb before 
trying to actually debug anything.  So, I haven't begun to worry about debug 
stubs.

Frankly, I'm confused as to where they'd go.  It seems to me I want to let 
the kernel start up on the pda and then use gdb to tell it to start running 
kaffe.  If that's true, I need debug stubs in kaffe.  Am I completely wrong 
with this idea?

Mark

>--
>Daniel Jacobowitz
>MontaVista Software                         Debian GNU/Linux Developer

_________________________________________________________________
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Re: cross debugging r3912 cpu with gdb

[Daniel Jacobowitz]

On Mon, Dec 08, 2003 at 12:48:44PM +0000, Mark and Janice Juszczec wrote:
> 
> Daniel
> 
> >
> >Then what ARE you using on the target?
> >
> 
> I have a kernel, busybox (for init and sh) and kaffe+associated files.  
> These have all been cross compiled from i386 for mipsel-linux using gcc 
> (2.95 or 3.0).
> 
> >You have to connect to some particular debug stub.  That determines
> >what protocol to use.
> >
> 
> 
> I wanted to test starting the whole thing up and connecting with gdb before 
> trying to actually debug anything.  So, I haven't begun to worry about 
> debug stubs.

GDB has to connect _to_ something :)  If you don't have a stub, nothing
on your target speaks the GDB protocol.

> Frankly, I'm confused as to where they'd go.  It seems to me I want to let 
> the kernel start up on the pda and then use gdb to tell it to start running 
> kaffe.  If that's true, I need debug stubs in kaffe.  Am I completely wrong 
> with this idea?

Yes.  I recommend you read the GDB manual, on the section describing
gdbserver.  GDB doesn't connect to the kernel at all, you start a
gdbserver process on the target with the path to kaffe.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer