[U-Boot] How to debug uboot code on Samsung S5pv210 chip by eclipse and JTAG?

[Marek Vasut]

Dear Wolfgang Denk,

> Dear =?GB2312?B?vOHKrw==?=,
> 
> In message <CAKM5mEg9rbi8yLsQfjawE74gh-
eu9p7prSgP=TSX7P9RJiMQAw at mail.gmail.com> you wrote:
> >     I have found some tutorials to debug uboot an samsung 2440 and
> > 6410 chip by JTAG .I also known I must write a init program or script
> > first .But I don't known to debug uboot on S5pv210 and write the init
> > DDR script.Anyone gives me a guide to establish the process.
> 
> Why would you need to initialize DDR though the JTAG debugger?

The system has some BootROM, which does the DDR init. But without special header 
in the NAND, the DDR won't be inited ... that was my point about initing it via 
the debugger.

> The common use of a JTAG debugger to debug U-Boot is _not_ to
> initialize the system at all though JTAG, as this will be done by
> U-Boot.  Just start the CPU out of reset.
> 
> Actually on quite a number of architectures U-Boot expects to find a
> virgin CPU right out of reset, and any previous meddling with the
> configuration may have unexpected (and usually adverse) effects.
> Better don't do it.
> 
> Best regards,
> 
> Wolfgang Denk

Best regards,
Marek Vasut