Startup now mostly works, except that the initial target state
is "unknown" ... previously, it refused to even start.
Getting that far required fixing the ircapture value (which
can never have been correct!) and the default JTAG clock rate,
then providing custom reset script.
The "reset" command is still iffy. DCSR updates, and loading
the debug handler, report numerous DR/IR capture failures.
But once that's done, "poll" reports that the CPU is halted
(which it shouldn't be, this was "reset run"!), due to the
rather curious reason "target-not-halted".
Summary: you still can't debug these parts, but it's closer.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Prerequisites:
The users of OpenOCD as well as computer programs interacting with OpenOCD are expecting that certain commands
do the same thing across all the targets.
Rules to follow when writing scripts:
1. The configuration script should be defined such as , for example, the following sequences are working:
reset
flash info <bank>
and
reset
flash erase_address <start> <len>
and
reset init
load
In most cases this can be accomplished by specifying the default startup mode as reset_init (target command
in the configuration file).
2. If the target is correctly configured, flash must be writable without any other helper commands. It is
assumed that all write-protect mechanisms should be disabled.
3. The configuration scripts should be defined such as the binary that was written to flash verifies
(turn off remapping, checksums, etc...)
flash write_image [file] <parameters>
verify_image [file] <parameters>
4. jtag_khz sets the maximum speed (or alternatively RCLK). If invoked
multiple times only the last setting is used.
interface/xxx.cfg files are always executed *before* target/xxx.cfg
files, so any jtag_khz in interface/xxx.cfg will be overridden by
target/xxx.cfg. jtag_khz in interface/xxx.cfg would then, effectively,
set the default JTAG speed.
Note that a target/xxx.cfg file can invoke another target/yyy.cfg file,
so one can create target subtype configurations where e.g. only
amount of DRAM, oscillator speeds differ and having a single
config file for the default/common settings.