| Message ID | 20220127201116.1154733-7-farosas@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/ppc: powerpc_excp improvements [74xx] (5/n) | expand |
On Thu, 27 Jan 2022, Fabiano Rosas wrote: > 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. Thanks, this should do it. Just some small comments below. > Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> > --- > 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) { In case you'll have another version, maybe drop the extra parenthesis around lev == here and below... > 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) { ...here. Or maybe even drop the lev local variable and just use env->error_code in the ifs directly? Only apprears twice now so could do without copying it to a local. But not a big deal so it's not worth a respin only for this. Regards, BALATON Zoltan > 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; >
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;
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 <farosas@linux.ibm.com> --- target/ppc/excp_helper.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-)