From bca2c6d9e09177c5a6959c3c372dab8211f39404 Mon Sep 17 00:00:00 2001 From: Fabiano Rosas Date: Fri, 28 Jan 2022 13:15:07 +0100 Subject: [PATCH] target/ppc: 74xx: System Call exception cleanup MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove the BookE code and add a comment explaining why we need to keep hypercall support even though this CPU does not have a hypervisor mode. Signed-off-by: Fabiano Rosas Message-Id: <20220127201116.1154733-7-farosas@linux.ibm.com> Signed-off-by: Cédric Le Goater --- target/ppc/excp_helper.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c index bb17b65dc0..396e25ed35 100644 --- a/target/ppc/excp_helper.c +++ b/target/ppc/excp_helper.c @@ -556,7 +556,7 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp) CPUState *cs = CPU(cpu); CPUPPCState *env = &cpu->env; target_ulong msr, new_msr, vector; - int srr0, srr1, lev = -1; + int srr0, srr1; if (excp <= POWERPC_EXCP_NONE || excp >= POWERPC_EXCP_NB) { cpu_abort(cs, "Invalid PowerPC exception %d. Aborting\n", excp); @@ -669,7 +669,8 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp) } break; case POWERPC_EXCP_SYSCALL: /* System call exception */ - lev = env->error_code; + { + int lev = env->error_code; if ((lev == 1) && cpu->vhyp) { dump_hcall(env); @@ -683,17 +684,21 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp) */ env->nip += 4; - /* "PAPR mode" built-in hypercall emulation */ + /* + * The Virtual Open Firmware (VOF) relies on the 'sc 1' + * instruction to communicate with QEMU. The pegasos2 machine + * uses VOF and the 74xx CPUs, so although the 74xx don't have + * HV mode, we need to keep hypercall support. + */ if ((lev == 1) && cpu->vhyp) { PPCVirtualHypervisorClass *vhc = PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp); vhc->hypercall(cpu->vhyp, cpu); return; } - if (lev == 1) { - new_msr |= (target_ulong)MSR_HVB; - } + break; + } case POWERPC_EXCP_FPU: /* Floating-point unavailable exception */ case POWERPC_EXCP_DECR: /* Decrementer exception */ break;