| Message ID | 20210413125448.1689545-2-npiggin@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | POWER9/POWER10 exception model fixes | expand |
Nicholas Piggin <npiggin@gmail.com> writes: > ISA v3.0 radix guest execution has a quirk in AIL behaviour such that > the LPCR[AIL] value can apply to hypervisor interrupts. > > This affects machines that emulate HV=1 mode (i.e., powernv9). > Ah ok, so we actually want to replicate the quirk in the pnv machine. Took me a while. Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > target/ppc/excp_helper.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c > index 85de7e6c90..b8881c0f85 100644 > --- a/target/ppc/excp_helper.c > +++ b/target/ppc/excp_helper.c > @@ -791,14 +791,23 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) > #endif > > /* > - * AIL only works if there is no HV transition and we are running > - * with translations enabled > + * AIL only works if MSR[IR] and MSR[DR] are both enabled. > */ > - if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1) || > - ((new_msr & MSR_HVB) && !(msr & MSR_HVB))) { > + if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1)) { > ail = 0; > } > > + /* > + * AIL does not work if there is a MSR[HV] 0->1 transition and the > + * partition is in HPT mode. For radix guests, such interrupts are > + * allowed to be delivered to the hypervisor in ail mode. > + */ > + if ((new_msr & MSR_HVB) && !(msr & MSR_HVB)) { > + if (!(env->spr[SPR_LPCR] & LPCR_HR)) { > + ail = 0; > + } > + } > + > vector = env->excp_vectors[excp]; > if (vector == (target_ulong)-1ULL) { > cpu_abort(cs, "Raised an exception without defined vector %d\n",
On 4/13/21 2:54 PM, Nicholas Piggin wrote: > ISA v3.0 radix guest execution has a quirk in AIL behaviour such that > the LPCR[AIL] value can apply to hypervisor interrupts. Shouldn't we test for P9 ? But I think you are using a new exception model for P10 in the next patch. I guess it's ok for now. > > This affects machines that emulate HV=1 mode (i.e., powernv9). > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > target/ppc/excp_helper.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c > index 85de7e6c90..b8881c0f85 100644 > --- a/target/ppc/excp_helper.c > +++ b/target/ppc/excp_helper.c > @@ -791,14 +791,23 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) > #endif > > /* > - * AIL only works if there is no HV transition and we are running > - * with translations enabled > + * AIL only works if MSR[IR] and MSR[DR] are both enabled. > */ > - if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1) || > - ((new_msr & MSR_HVB) && !(msr & MSR_HVB))) { > + if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1)) { > ail = 0; > } > > + /* > + * AIL does not work if there is a MSR[HV] 0->1 transition and the > + * partition is in HPT mode. For radix guests, such interrupts are > + * allowed to be delivered to the hypervisor in ail mode. > + */ > + if ((new_msr & MSR_HVB) && !(msr & MSR_HVB)) { > + if (!(env->spr[SPR_LPCR] & LPCR_HR)) { We have a ppc64_v3_radix() helper but this is minor. C. > + ail = 0; > + } > + } > + > vector = env->excp_vectors[excp]; > if (vector == (target_ulong)-1ULL) { > cpu_abort(cs, "Raised an exception without defined vector %d\n", >
Excerpts from Fabiano Rosas's message of April 13, 2021 11:48 pm: > Nicholas Piggin <npiggin@gmail.com> writes: > >> ISA v3.0 radix guest execution has a quirk in AIL behaviour such that >> the LPCR[AIL] value can apply to hypervisor interrupts. >> >> This affects machines that emulate HV=1 mode (i.e., powernv9). >> > > Ah ok, so we actually want to replicate the quirk in the pnv > machine. Took me a while. Yes. Quirk is probably the wrong word for me to use. It's architected behaviour so it must be implemented, it's just slightly surprising / easy to miss. > > Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Thanks, Nick > >> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> >> --- >> target/ppc/excp_helper.c | 17 +++++++++++++---- >> 1 file changed, 13 insertions(+), 4 deletions(-) >> >> diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c >> index 85de7e6c90..b8881c0f85 100644 >> --- a/target/ppc/excp_helper.c >> +++ b/target/ppc/excp_helper.c >> @@ -791,14 +791,23 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) >> #endif >> >> /* >> - * AIL only works if there is no HV transition and we are running >> - * with translations enabled >> + * AIL only works if MSR[IR] and MSR[DR] are both enabled. >> */ >> - if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1) || >> - ((new_msr & MSR_HVB) && !(msr & MSR_HVB))) { >> + if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1)) { >> ail = 0; >> } >> >> + /* >> + * AIL does not work if there is a MSR[HV] 0->1 transition and the >> + * partition is in HPT mode. For radix guests, such interrupts are >> + * allowed to be delivered to the hypervisor in ail mode. >> + */ >> + if ((new_msr & MSR_HVB) && !(msr & MSR_HVB)) { >> + if (!(env->spr[SPR_LPCR] & LPCR_HR)) { >> + ail = 0; >> + } >> + } >> + >> vector = env->excp_vectors[excp]; >> if (vector == (target_ulong)-1ULL) { >> cpu_abort(cs, "Raised an exception without defined vector %d\n", >
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c index 85de7e6c90..b8881c0f85 100644 --- a/target/ppc/excp_helper.c +++ b/target/ppc/excp_helper.c @@ -791,14 +791,23 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) #endif /* - * AIL only works if there is no HV transition and we are running - * with translations enabled + * AIL only works if MSR[IR] and MSR[DR] are both enabled. */ - if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1) || - ((new_msr & MSR_HVB) && !(msr & MSR_HVB))) { + if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1)) { ail = 0; } + /* + * AIL does not work if there is a MSR[HV] 0->1 transition and the + * partition is in HPT mode. For radix guests, such interrupts are + * allowed to be delivered to the hypervisor in ail mode. + */ + if ((new_msr & MSR_HVB) && !(msr & MSR_HVB)) { + if (!(env->spr[SPR_LPCR] & LPCR_HR)) { + ail = 0; + } + } + vector = env->excp_vectors[excp]; if (vector == (target_ulong)-1ULL) { cpu_abort(cs, "Raised an exception without defined vector %d\n",
ISA v3.0 radix guest execution has a quirk in AIL behaviour such that the LPCR[AIL] value can apply to hypervisor interrupts. This affects machines that emulate HV=1 mode (i.e., powernv9). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- target/ppc/excp_helper.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)