target/arc: introduce basic smp support

EvgeniiDidin commented 4 years ago

With this commit we introduce basic SMP support for ARC targets. Only running smp application in telnet is supported, GDB is not supported yet.

SMP support starts with running "smp target1 target2..." command during target initialization. This command creates linked list of targets and sets for each ->smp=1. Next running poll() function if one core is halted, it is necessary to poll other cores in list. And finally resuming execution it is necessary to restore context on each target and run each core.

Major changes in this commit:

Add "arc_smp on/of" handlers.
Modify resume, poll functions to process slave cores.
Introduced arc_dbg_set_pc() and arc_ocd_poll_smp() functions
Introduced target/board snps_hsdk_smp.cfg files.

Usage via telnet:

load /path/to/bin resume

Signed-off-by: Evgeniy Didin didin@synopsys.com

abrodkin commented 4 years ago

@galak may we get this one in upcoming 0.11.3 SDK so OpenOCD is usable with by default SMP-enabled HSDK board finally?

galak commented 4 years ago

Yes, I can pull that in.

zephyrproject-rtos / openocd

target/arc: introduce basic smp support #25