Re: [Openocd-development] Incorrect chain detection for SoC...

[Ø. H. <oyv...@zy...>]

On Thu, Sep 25, 2008 at 11:57 PM, Georg Acher <ac...@in...> wrote:
> Hi,
> I'm currently working on a settop-box chip from Conexant. It contains two
> ARMs, a 1176 and a 926. The 1176 is the one I'm targeting for flashing over
> JTAG (no debugging or other fancy stuff).

Flashing is actually pretty fancy as it requires OpenOCD to execute
code on the target.

> Unfortunately, openocd has huge problems even in detecting in the JTAG
> chain. Already all of the Ids are wrong...

This could very well be a problem with the driver / JTAG device you
are using.

> And now the result of the openocd scan (HW is parport wiggler, svn checkout
> a few hours ago):

We have not been able to get the parport dongle to talk relyably to
the ARM11 (iMX31) we have here. (ZY1000 works fine).

Perhaps you need RCLK?

> A cross check with the Xilinx-impact-tool and its USB-JTAG adapter also
> showed the message "too many devices" and then a crash occured ;-) Looks
> like the large number of devices is no HW/level/cable problem.

We found that the iMX31 is finicky and doesn't work with the parport dongle,
and there are lots of *cheap* analogue stages out there so it is not at all
unthinkable that two out of three will have problems with something as
particular as your setup.

> Are there any hints what I can do? I'm accepting all ugly hacks ;-)

I wouldn't want to dive into this without having access to hw :-)


-- 
Øyvind Harboe
http://www.zylin.com/zy1000.html
ARM7 ARM9 XScale Cortex
JTAG debugger and flash programmer