Failed to remove breakpoint instruction in polarfire icicle board

[mbilal100]

While debugging Linux kernel via jtag on Polarfire icicle board, getting following error on GDB breakpoint removal packet

Error: Failed to restore instruction for 2-byte breakpoint at 0xffffffff8000c00e

Most of the time this error is come when i.e

• insert a breakpoint
• Let this breakpoint hit and remain idle for 3-4 min and then resume the debugging will get this error

I examined all the harts to see the memory access and found that first hart is not be able to read that breakpoint address memory.

telnet logs:

Failed to restore instruction for 2-byte breakpoint at 0xffffffff8000c00e
> mpfs.hart1_u54_1 mdb 0xffffffff8000c00e 2
0xffffffff8000c00e: 00 00 

> mpfs.hart2_u54_2 mdb 0xffffffff8000c00e 2
0xffffffff8000c00e: 02 90 

> mpfs.hart3_u54_3 mdb 0xffffffff8000c00e 2
0xffffffff8000c00e: 02 90 

> mpfs.hart4_u54_4 mdb 0xffffffff8000c00e 2
0xffffffff8000c00e: 02 90 

so hart 1 is not be able to access the memory at all.

I'm running following LTS linux
Linux icicle-kit-es-flex 5.15.79-linux4microchip+fpga-2022.09 #1 SMP Thu Nov 24 14:15:55 UTC 2022 riscv64 GNU/Linux

Linux cmdline

~# cat /proc/cmdline 
earlycon=sbi uio_pdrv_genirq.of_id=generic-uio root=/dev/mmcblk0p4 rootwait rw rodata=off cpuidle.off=1 nohlt nowatchdog

Enabled openocd debug_level 3 and got following error on accessing the memory

Debug: 13395 273019 riscv-013.c:779 execute_abstract_command(): command=0x371009; access register, size=64, postexec=1, transfer=1, write=1, regno=0x1009
Debug: 13396 273019 riscv-013.c:398 scan(): 41b w 00371009 @17 -> + 00000000 @00; 1i
Debug: 13397 273020 riscv-013.c:398 scan(): 41b r 00000000 @16 -> + 00000000 @00; 1i
Debug: 13398 273020 riscv-013.c:398 scan(): 41b - 00000000 @16 -> + 10000302 @16; 1i
Debug: 13399 273020 riscv-013.c:408 scan():  ->  progbufsize=16 cmderr=3 datacount=2
Debug: 13400 273020 riscv-013.c:802 execute_abstract_command(): command 0x371009 failed; abstractcs=0x10000302
Debug: 13401 273021 riscv-013.c:398 scan(): 41b w 00000700 @16 -> + 00000000 @00; 1i
Debug: 13402 273021 riscv-013.c:408 scan():  cmderr=7 -> 
Debug: 13403 273021 riscv-013.c:398 scan(): 41b - 00000000 @16 -> + 10000302 @16; 1i
Debug: 13404 273021 riscv-013.c:408 scan():  ->  progbufsize=16 cmderr=3 datacount=2
Debug: 13405 273021 riscv-013.c:398 scan(): 41b w 00000000 @18 -> + 00000000 @00; 1i
Debug: 13406 273022 riscv-013.c:398 scan(): 41b - 00000000 @18 -> + 00000000 @18; 1i
Debug: 13407 273022 riscv-013.c:1298 register_write_direct(): {1} s1 <- 0xa02cf48

I'm also attaching the complete openocd, telnet, gdb and openocd config logs.

Can anyone please suggest why I'm getting this error ?

bug-report.zip