Message ID | e38e606e937e7b6dfc679c881c762c7037b325a4.1686868895.git.balaton@eik.bme.hu |
---|---|
State | New |
Headers | show |
Series | Misc clean ups to target/ppc exception handling | expand |
On Fri Jun 16, 2023 at 9:03 AM AEST, BALATON Zoltan wrote: > Most exceptions are raised with nip pointing to the faulting > instruction but the sc instruction generating a syscall exception > leaves nip pointing to next instruction. Fix gen_sc to not use > gen_exception_err() which sets nip back but correctly set nip to > pc_next so we don't have to patch this in the exception handlers. > > This changes the nip logged in dump_syscall and dump_hcall debug > functions but now this matches how nip would be on a real CPU. I think this is okay. I'll just send a possible scv change after this goes in. Reviewed-by: Nicholas Piggin <npiggin@gmail.com> > > Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu> > --- > target/ppc/excp_helper.c | 39 --------------------------------------- > target/ppc/translate.c | 8 +++++--- > 2 files changed, 5 insertions(+), 42 deletions(-) > > diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c > index f19a0f2d1d..903216c2a6 100644 > --- a/target/ppc/excp_helper.c > +++ b/target/ppc/excp_helper.c > @@ -495,12 +495,6 @@ static void powerpc_excp_40x(PowerPCCPU *cpu, int excp) > break; > case POWERPC_EXCP_SYSCALL: /* System call exception */ > dump_syscall(env); > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > break; > case POWERPC_EXCP_FIT: /* Fixed-interval timer interrupt */ > trace_ppc_excp_print("FIT"); > @@ -611,12 +605,6 @@ static void powerpc_excp_6xx(PowerPCCPU *cpu, int excp) > break; > case POWERPC_EXCP_SYSCALL: /* System call exception */ > dump_syscall(env); > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > break; > case POWERPC_EXCP_FPU: /* Floating-point unavailable exception */ > case POWERPC_EXCP_DECR: /* Decrementer exception */ > @@ -759,13 +747,6 @@ static void powerpc_excp_7xx(PowerPCCPU *cpu, int excp) > } else { > dump_syscall(env); > } > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > - > /* > * The Virtual Open Firmware (VOF) relies on the 'sc 1' > * instruction to communicate with QEMU. The pegasos2 machine > @@ -910,13 +891,6 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp) > } else { > dump_syscall(env); > } > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > - > /* > * The Virtual Open Firmware (VOF) relies on the 'sc 1' > * instruction to communicate with QEMU. The pegasos2 machine > @@ -1075,12 +1049,6 @@ static void powerpc_excp_booke(PowerPCCPU *cpu, int excp) > break; > case POWERPC_EXCP_SYSCALL: /* System call exception */ > dump_syscall(env); > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > break; > case POWERPC_EXCP_FPU: /* Floating-point unavailable exception */ > case POWERPC_EXCP_APU: /* Auxiliary processor unavailable */ > @@ -1322,13 +1290,6 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp) > } else { > dump_syscall(env); > } > - > - /* > - * We need to correct the NIP which in this case is supposed > - * to point to the next instruction > - */ > - env->nip += 4; > - > /* "PAPR mode" built-in hypercall emulation */ > if (lev == 1 && books_vhyp_handles_hcall(cpu)) { > PPCVirtualHypervisorClass *vhc = > diff --git a/target/ppc/translate.c b/target/ppc/translate.c > index a32a9b8a5f..4260d3d66f 100644 > --- a/target/ppc/translate.c > +++ b/target/ppc/translate.c > @@ -4419,10 +4419,12 @@ static void gen_hrfid(DisasContext *ctx) > #endif > static void gen_sc(DisasContext *ctx) > { > - uint32_t lev; > + uint32_t lev = (ctx->opcode >> 5) & 0x7F; > > - lev = (ctx->opcode >> 5) & 0x7F; > - gen_exception_err(ctx, POWERPC_SYSCALL, lev); > + gen_update_nip(ctx, ctx->base.pc_next); > + gen_helper_raise_exception_err(cpu_env, tcg_constant_i32(POWERPC_SYSCALL), > + tcg_constant_i32(lev)); > + ctx->base.is_jmp = DISAS_NORETURN; > } > > #if defined(TARGET_PPC64) > -- > 2.30.9
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c index f19a0f2d1d..903216c2a6 100644 --- a/target/ppc/excp_helper.c +++ b/target/ppc/excp_helper.c @@ -495,12 +495,6 @@ static void powerpc_excp_40x(PowerPCCPU *cpu, int excp) break; case POWERPC_EXCP_SYSCALL: /* System call exception */ dump_syscall(env); - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; break; case POWERPC_EXCP_FIT: /* Fixed-interval timer interrupt */ trace_ppc_excp_print("FIT"); @@ -611,12 +605,6 @@ static void powerpc_excp_6xx(PowerPCCPU *cpu, int excp) break; case POWERPC_EXCP_SYSCALL: /* System call exception */ dump_syscall(env); - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; break; case POWERPC_EXCP_FPU: /* Floating-point unavailable exception */ case POWERPC_EXCP_DECR: /* Decrementer exception */ @@ -759,13 +747,6 @@ static void powerpc_excp_7xx(PowerPCCPU *cpu, int excp) } else { dump_syscall(env); } - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; - /* * The Virtual Open Firmware (VOF) relies on the 'sc 1' * instruction to communicate with QEMU. The pegasos2 machine @@ -910,13 +891,6 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp) } else { dump_syscall(env); } - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; - /* * The Virtual Open Firmware (VOF) relies on the 'sc 1' * instruction to communicate with QEMU. The pegasos2 machine @@ -1075,12 +1049,6 @@ static void powerpc_excp_booke(PowerPCCPU *cpu, int excp) break; case POWERPC_EXCP_SYSCALL: /* System call exception */ dump_syscall(env); - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; break; case POWERPC_EXCP_FPU: /* Floating-point unavailable exception */ case POWERPC_EXCP_APU: /* Auxiliary processor unavailable */ @@ -1322,13 +1290,6 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp) } else { dump_syscall(env); } - - /* - * We need to correct the NIP which in this case is supposed - * to point to the next instruction - */ - env->nip += 4; - /* "PAPR mode" built-in hypercall emulation */ if (lev == 1 && books_vhyp_handles_hcall(cpu)) { PPCVirtualHypervisorClass *vhc = diff --git a/target/ppc/translate.c b/target/ppc/translate.c index a32a9b8a5f..4260d3d66f 100644 --- a/target/ppc/translate.c +++ b/target/ppc/translate.c @@ -4419,10 +4419,12 @@ static void gen_hrfid(DisasContext *ctx) #endif static void gen_sc(DisasContext *ctx) { - uint32_t lev; + uint32_t lev = (ctx->opcode >> 5) & 0x7F; - lev = (ctx->opcode >> 5) & 0x7F; - gen_exception_err(ctx, POWERPC_SYSCALL, lev); + gen_update_nip(ctx, ctx->base.pc_next); + gen_helper_raise_exception_err(cpu_env, tcg_constant_i32(POWERPC_SYSCALL), + tcg_constant_i32(lev)); + ctx->base.is_jmp = DISAS_NORETURN; } #if defined(TARGET_PPC64)
Most exceptions are raised with nip pointing to the faulting instruction but the sc instruction generating a syscall exception leaves nip pointing to next instruction. Fix gen_sc to not use gen_exception_err() which sets nip back but correctly set nip to pc_next so we don't have to patch this in the exception handlers. This changes the nip logged in dump_syscall and dump_hcall debug functions but now this matches how nip would be on a real CPU. Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu> --- target/ppc/excp_helper.c | 39 --------------------------------------- target/ppc/translate.c | 8 +++++--- 2 files changed, 5 insertions(+), 42 deletions(-)