Commit Graph

2 Commits

Author SHA1 Message Date
Himanshu Chauhan
1ec353d504 lib: sbi: Use mask to check the free bit during trigger allocation
The trigger allocation function uses bit shift instead of mask to check the
mapped status of the triggers. This causes index 0 to be return always. As a
result, the older triggers are overwritten.

Use the mask for MAPPED field in state word to check if the trigger is mapped.

Fixes: 97f234f15 ("lib: sbi: Introduce the SBI debug triggers extension support")
Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2024-02-05 10:23:01 +05:30
Himanshu Chauhan
97f234f15c lib: sbi: Introduce the SBI debug triggers extension support
RISC-V Debug specification includes Sdtrig ISA extension
which describes Trigger Module. Triggers can cause
a breakpoint exception or trace action without execution
of a special instruction. They can be used to implement
hardware breakpoints and watchpoints for native debugging.

The SBI Debut Trigger extension (Draft v6) can be found at:
https://lists.riscv.org/g/tech-debug/topic/99825362#1302

This patch is an initial implementation of SBI Debug
Trigger Extension (Draft v6) in OpenSBI.

The following features are supported:
 * mcontrol, mcontrol6 triggers
 * Breakpoint and trace actions

NOTE: Chained triggers are not supported

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2024-01-10 10:55:42 +05:30