Re:Linux support for dev tools
That's great. I have been reading around on this topic and was gradually gravitating towards OpenOCD as a starting point. It's good to know that better minds than mine are taking the same path.
The "proprietary" nature of the JTAG specs should be a non-issue - the 811 datasheet says:
For detailed information on the order of the input, output, and output enable bits for each of the GPIO ports, please refer to the Stellaris Family Boundary Scan Description Language (BSDL) files, downloadable from www.luminarymicro.com.
Unfortunately, I haven't managed to find them on the site anywhere.
Also, as far as I can glean (I am no JTAG expert by any means) the JTAG controller in the 811 starts up in a mode which effectively grants access directly to the M3 core, so if we can drive most things from there, we may be OK, at least to start with. Again, from the spec:
The LMI JTAG controller works with the ARM JTAG controller built into the Cortex-M3 core. This is implemented by multiplexing the TDO outputs from both JTAG controllers. ARM JTAG instructions select the ARM TDO output while LMI JTAG instructions select the LMI TDO outputs.
The basic minimum functionality we would need is a way to program the flash in the device via JTAG. I understand that you can do this via address-port bit-banging if you have access to the flash control lines, although the more usual way to do it is to program the on-board SRAM with a bootloader program, which itself manages the interaction with the Flash. SRAM loading strikes me as simpler than Flash loading - it has less control lines to worry about.
I don't know if this is what OpenOCD typically does for flash loading - I am still in the reading stage and my spare tinkering time seems to evaporate terrifyingly fast these days.
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