> reset halt
JTAG tap: at91sam7s.cpu tap/device found: 0x3f0f0f0f (mfg: 0x787, part: 0xf0f0, ver: 0x3)
srst pulls trst - can not reset into halted mode. Issuing halt after reset.
target state: halted
target halted in Thumb state due to debug-request, current mode: Supervisor
cpsr: 0x400000f3 pc: 0x00000110
> at91sam7sx mass_erase 0
invalid command name "at91sam7sx"
> srst pulls trst - can not reset into halted mode. Issuing halt after reset.
invalid command name "srst"
> target state: halted
I think this message expalins what is the issue "can not reset into halted mode. Issuing halt after reset."
Instead of "reset halt" try with just "reset" or "reset run" or after "reset halt" execute also "run".
It should be better idea to join the openocd mail lists, or check the openocd documentation, better chance to solve issues related to openocd.
https://jacobmossberg.se/posts/2017/01/10/using-openocd-flash-arm-cortex-m3.html