Privileged spec section 4.1.9 mentions:
"When a trap is taken into S-mode, stval is written with
exception-specific information to assist software in handling the trap.
(...)
If stval is written with a nonzero value when a breakpoint,
address-misaligned, access-fault, or page-fault exception occurs on an
instruction fetch, load, or store, then stval will contain the faulting
virtual address."
A similar text is found for mtval in section 3.1.16.
Setting mtval/stval in this scenario is optional, but some softwares read
these regs when handling ebreaks.
Write 'badaddr' in all ebreak breakpoints to write the appropriate
'tval' during riscv_do_cpu_interrrupt().
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
target/riscv/insn_trans/trans_privileged.c.inc | 2 ++
1 file changed, 2 insertions(+)
diff --git a/target/riscv/insn_trans/trans_privileged.c.inc b/target/riscv/insn_trans/trans_privileged.c.inc
index 620ab54eb0..bc5263a4e0 100644
--- a/target/riscv/insn_trans/trans_privileged.c.inc
+++ b/target/riscv/insn_trans/trans_privileged.c.inc
@@ -62,6 +62,8 @@ static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a)
if (pre == 0x01f01013 && ebreak == 0x00100073 && post == 0x40705013) {
generate_exception(ctx, RISCV_EXCP_SEMIHOST);
} else {
+ tcg_gen_st_tl(tcg_constant_tl(ebreak_addr), tcg_env,
+ offsetof(CPURISCVState, badaddr));
generate_exception(ctx, RISCV_EXCP_BREAKPOINT);
}
return true;
--
2.44.0
On Wed, Apr 17, 2024 at 9:05 AM Daniel Henrique Barboza
<dbarboza@ventanamicro.com> wrote:
>
> Privileged spec section 4.1.9 mentions:
>
> "When a trap is taken into S-mode, stval is written with
> exception-specific information to assist software in handling the trap.
> (...)
>
> If stval is written with a nonzero value when a breakpoint,
> address-misaligned, access-fault, or page-fault exception occurs on an
> instruction fetch, load, or store, then stval will contain the faulting
> virtual address."
>
> A similar text is found for mtval in section 3.1.16.
>
> Setting mtval/stval in this scenario is optional, but some softwares read
> these regs when handling ebreaks.
>
> Write 'badaddr' in all ebreak breakpoints to write the appropriate
> 'tval' during riscv_do_cpu_interrrupt().
>
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
> target/riscv/insn_trans/trans_privileged.c.inc | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/target/riscv/insn_trans/trans_privileged.c.inc b/target/riscv/insn_trans/trans_privileged.c.inc
> index 620ab54eb0..bc5263a4e0 100644
> --- a/target/riscv/insn_trans/trans_privileged.c.inc
> +++ b/target/riscv/insn_trans/trans_privileged.c.inc
> @@ -62,6 +62,8 @@ static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a)
> if (pre == 0x01f01013 && ebreak == 0x00100073 && post == 0x40705013) {
> generate_exception(ctx, RISCV_EXCP_SEMIHOST);
> } else {
> + tcg_gen_st_tl(tcg_constant_tl(ebreak_addr), tcg_env,
> + offsetof(CPURISCVState, badaddr));
> generate_exception(ctx, RISCV_EXCP_BREAKPOINT);
> }
> return true;
> --
> 2.44.0
>
>
On 2024/4/17 7:04, Daniel Henrique Barboza wrote:
> Privileged spec section 4.1.9 mentions:
>
> "When a trap is taken into S-mode, stval is written with
> exception-specific information to assist software in handling the trap.
> (...)
>
> If stval is written with a nonzero value when a breakpoint,
> address-misaligned, access-fault, or page-fault exception occurs on an
> instruction fetch, load, or store, then stval will contain the faulting
> virtual address."
>
> A similar text is found for mtval in section 3.1.16.
>
> Setting mtval/stval in this scenario is optional, but some softwares read
> these regs when handling ebreaks.
>
> Write 'badaddr' in all ebreak breakpoints to write the appropriate
> 'tval' during riscv_do_cpu_interrrupt().
>
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
> target/riscv/insn_trans/trans_privileged.c.inc | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/target/riscv/insn_trans/trans_privileged.c.inc b/target/riscv/insn_trans/trans_privileged.c.inc
> index 620ab54eb0..bc5263a4e0 100644
> --- a/target/riscv/insn_trans/trans_privileged.c.inc
> +++ b/target/riscv/insn_trans/trans_privileged.c.inc
> @@ -62,6 +62,8 @@ static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a)
> if (pre == 0x01f01013 && ebreak == 0x00100073 && post == 0x40705013) {
> generate_exception(ctx, RISCV_EXCP_SEMIHOST);
> } else {
> + tcg_gen_st_tl(tcg_constant_tl(ebreak_addr), tcg_env,
> + offsetof(CPURISCVState, badaddr));
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Zhiwei
> generate_exception(ctx, RISCV_EXCP_BREAKPOINT);
> }
> return true;
On 4/16/24 16:04, Daniel Henrique Barboza wrote: > Privileged spec section 4.1.9 mentions: > > "When a trap is taken into S-mode, stval is written with > exception-specific information to assist software in handling the trap. > (...) > > If stval is written with a nonzero value when a breakpoint, > address-misaligned, access-fault, or page-fault exception occurs on an > instruction fetch, load, or store, then stval will contain the faulting > virtual address." > > A similar text is found for mtval in section 3.1.16. > > Setting mtval/stval in this scenario is optional, but some softwares read > these regs when handling ebreaks. > > Write 'badaddr' in all ebreak breakpoints to write the appropriate > 'tval' during riscv_do_cpu_interrrupt(). > > Signed-off-by: Daniel Henrique Barboza<dbarboza@ventanamicro.com> > --- > target/riscv/insn_trans/trans_privileged.c.inc | 2 ++ > 1 file changed, 2 insertions(+) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
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