On Fri Jun 16, 2023 at 9:03 AM AEST, BALATON Zoltan wrote:
From: Nicholas Piggin <npiggin@gmail.com>
Unlike sc, for scv a facility unavailable interrupt must be generated
if FSCR[SCV]=0 so we can't raise the exception with nip set to next
instruction but we can move advancing nip if the FSCR check passes to
helper_scv so the exception handler does not need to change it.
[balaton: added commit message]
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Ah you sent it, fine, thank you. But actually now I look again,
now we're off by one in the other direction for the dumps.
Thanks,
Nick
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 0e21cb4451..d7f42639c8 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -117,7 +117,7 @@ static void dump_syscall(CPUPPCState *env)
ppc_dump_gpr(env, 0), ppc_dump_gpr(env, 3),
ppc_dump_gpr(env, 4), ppc_dump_gpr(env, 5),
ppc_dump_gpr(env, 6), ppc_dump_gpr(env, 7),
- ppc_dump_gpr(env, 8), env->nip);
+ ppc_dump_gpr(env, 8), env->nip - 4);
}
static void dump_hcall(CPUPPCState *env)
@@ -132,7 +132,7 @@ static void dump_hcall(CPUPPCState *env)
ppc_dump_gpr(env, 7), ppc_dump_gpr(env, 8),
ppc_dump_gpr(env, 9), ppc_dump_gpr(env, 10),
ppc_dump_gpr(env, 11), ppc_dump_gpr(env, 12),
- env->nip);
+ env->nip - 4);
}
#ifdef CONFIG_TCG
---
This needs SoB from Nick
target/ppc/excp_helper.c | 2 +-
target/ppc/translate.c | 6 +++++-
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 903216c2a6..ef363b0285 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -1304,7 +1304,6 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp)
case POWERPC_EXCP_SYSCALL_VECTORED: /* scv exception */
lev = env->error_code;
dump_syscall(env);
- env->nip += 4;
new_msr |= env->msr & ((target_ulong)1 << MSR_EE);
new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
@@ -2410,6 +2409,7 @@ void helper_ppc_maybe_interrupt(CPUPPCState *env)
void helper_scv(CPUPPCState *env, uint32_t lev)
{
if (env->spr[SPR_FSCR] & (1ull << FSCR_SCV)) {
+ env->nip += 4;
raise_exception_err(env, POWERPC_EXCP_SYSCALL_VECTORED, lev);
} else {
raise_exception_err(env, POWERPC_EXCP_FU, FSCR_IC_SCV);
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index 4260d3d66f..0360a17fb3 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -4433,7 +4433,11 @@ static void gen_scv(DisasContext *ctx)
{
uint32_t lev = (ctx->opcode >> 5) & 0x7F;
- /* Set the PC back to the faulting instruction. */
+ /*
+ * Set the PC back to the scv instruction (unlike sc), because a facility
+ * unavailable interrupt must be generated if FSCR[SCV]=0. The helper
+ * advances nip if the FSCR check passes.
+ */
gen_update_nip(ctx, ctx->cia);
gen_helper_scv(cpu_env, tcg_constant_i32(lev));
--
2.30.9