Re: [Openocd-development] Writing to flash using gdb

[Jonathan L. <ji...@eC...>]

kitts wrote:
> On Monday 18 Feb 2008 8:59:27 pm you wrote:
> 
>>>I would like to know if i can
>>>follow this method with openocd as it would save a lot of development
>>>time. I would request anyone with any knowledge on this to guide me as i
>>>was unable to find any openocd examples that followed this method.
>>
>>openocd implements the required functionality, or at least it's meant to
>>;-). So it's up to you to drive GDB to use it. You will only be able to do
>>it from kdevelop if kdevelop gives you a GDB command line you can use.
>>Note that the feature is only available in GDB 6.6 and later.
> 
> 
> Thanks for replying. Yes KDevelop does provide a GDB command line but why do i 
> need that?

To set up the memory regions. I guess you can put them in a .gdbinit file 
if you know what Kdevelop's current working directory is going to be when 
it runs GDB.

>>The key is to define your memory map in GDB correctly to indicate which
>>memory regions are flash. Then when you do a 'load' it automatically
>>reprograms the flash.
> 
> Do you have any example? How do i specify memory regions? Would this mean that 
> my gdbinit script mostly remains the same for RAM and FLASH operation except 
> for the memory region information (and the hardware/software breakpoints 
> config)?

Having correct memory region info is something that can exist whatever the 
aim of the config. And according to a recent message here, recent GDB 
already apparently sets the correct sort of breakpoint if a memory region 
is marked read-only (hardware bp) or read-write (software bp). My GDB is a 
little older and it didn't work for me (6.4), but you'll need 6.6+ anyway 
for the flash support. Anyway, you should be able to have the same config 
I'm sure.

Here's the doc on the 'mem' command which sets up the regions:
http://sourceware.org/gdb/current/onlinedocs/gdb_9.html#SEC73

At some point in the future it will probably be possible for openocd to 
provide the memory region info to GDB, but it isn't yet.

Jifl
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