| Message ID | 20240311185200.2185753-4-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | misc ppc patches | expand |
Hi Nick, One cosmetic comment, in case you are doing a re-spin: On 3/12/24 00:21, Nicholas Piggin wrote: > SAO is a page table attribute that strengthens the memory ordering of > accesses. QEMU with MTTCG does not implement this, so clear it in > ibm,pa-features. This is an obscure feature that has been removed from > POWER10 ISA v3.1, there isn't much concern with removing it. > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > hw/ppc/pnv.c | 2 +- > hw/ppc/spapr.c | 14 ++++++++++---- > 2 files changed, 11 insertions(+), 5 deletions(-) > > diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c > index 0b47b92baa..aa9786e970 100644 > --- a/hw/ppc/pnv.c > +++ b/hw/ppc/pnv.c > @@ -150,7 +150,7 @@ static void pnv_dt_core(PnvChip *chip, PnvCore *pc, void *fdt) > uint32_t page_sizes_prop[64]; > size_t page_sizes_prop_size; > const uint8_t pa_features[] = { 24, 0, > - 0xf6, 0x3f, 0xc7, 0xc0, 0x80, 0xf0, > + 0xf6, 0x3f, 0xc7, 0xc0, 0x00, 0xf0, > 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, > 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, > 0x80, 0x00, 0x80, 0x00, 0x80, 0x00 }; > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 55263f0815..5099f12cc6 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -234,16 +234,16 @@ static void spapr_dt_pa_features(SpaprMachineState *spapr, > void *fdt, int offset) > { > uint8_t pa_features_206[] = { 6, 0, > - 0xf6, 0x1f, 0xc7, 0x00, 0x80, 0xc0 }; > + 0xf6, 0x1f, 0xc7, 0x00, 0x00, 0xc0 }; > uint8_t pa_features_207[] = { 24, 0, > - 0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0, > + 0xf6, 0x1f, 0xc7, 0xc0, 0x00, 0xf0, > 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, > 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, > 0x80, 0x00, 0x80, 0x00, 0x00, 0x00 }; > uint8_t pa_features_300[] = { 66, 0, > /* 0: MMU|FPU|SLB|RUN|DABR|NX, 1: fri[nzpm]|DABRX|SPRG3|SLB0|PP110 */ > - /* 2: VPM|DS205|PPR|DS202|DS206, 3: LSD|URG, SSO, 5: LE|CFAR|EB|LSQ */ > - 0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0, /* 0 - 5 */ > + /* 2: VPM|DS205|PPR|DS202|DS206, 3: LSD|URG, 5: LE|CFAR|EB|LSQ */ Do we want to mention in comments SSO (disabled), also .. > + 0xf6, 0x1f, 0xc7, 0xc0, 0x00, 0xf0, /* 0 - 5 */ > /* 6: DS207 */ > 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, /* 6 - 11 */ > /* 16: Vector */ > @@ -284,6 +284,12 @@ static void spapr_dt_pa_features(SpaprMachineState *spapr, > return; > } > > + /* > + * SSO (SAO) ordering is supported on KVM and thread=single hosts, > + * but not MTTCG, so disable it. To advertise it, a cap would have > + * to be added, or support implemented for MTTCG. > + */ > + This comment could go in the beginning where we are actually disabling it. Otherwise, Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com> > if (ppc_hash64_has(cpu, PPC_HASH64_CI_LARGEPAGE)) { > /* > * Note: we keep CI large pages off by default because a 64K capable
diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c index 0b47b92baa..aa9786e970 100644 --- a/hw/ppc/pnv.c +++ b/hw/ppc/pnv.c @@ -150,7 +150,7 @@ static void pnv_dt_core(PnvChip *chip, PnvCore *pc, void *fdt) uint32_t page_sizes_prop[64]; size_t page_sizes_prop_size; const uint8_t pa_features[] = { 24, 0, - 0xf6, 0x3f, 0xc7, 0xc0, 0x80, 0xf0, + 0xf6, 0x3f, 0xc7, 0xc0, 0x00, 0xf0, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x80, 0x00, 0x80, 0x00, 0x80, 0x00 }; diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 55263f0815..5099f12cc6 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -234,16 +234,16 @@ static void spapr_dt_pa_features(SpaprMachineState *spapr, void *fdt, int offset) { uint8_t pa_features_206[] = { 6, 0, - 0xf6, 0x1f, 0xc7, 0x00, 0x80, 0xc0 }; + 0xf6, 0x1f, 0xc7, 0x00, 0x00, 0xc0 }; uint8_t pa_features_207[] = { 24, 0, - 0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0, + 0xf6, 0x1f, 0xc7, 0xc0, 0x00, 0xf0, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x80, 0x00, 0x80, 0x00, 0x00, 0x00 }; uint8_t pa_features_300[] = { 66, 0, /* 0: MMU|FPU|SLB|RUN|DABR|NX, 1: fri[nzpm]|DABRX|SPRG3|SLB0|PP110 */ - /* 2: VPM|DS205|PPR|DS202|DS206, 3: LSD|URG, SSO, 5: LE|CFAR|EB|LSQ */ - 0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0, /* 0 - 5 */ + /* 2: VPM|DS205|PPR|DS202|DS206, 3: LSD|URG, 5: LE|CFAR|EB|LSQ */ + 0xf6, 0x1f, 0xc7, 0xc0, 0x00, 0xf0, /* 0 - 5 */ /* 6: DS207 */ 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, /* 6 - 11 */ /* 16: Vector */ @@ -284,6 +284,12 @@ static void spapr_dt_pa_features(SpaprMachineState *spapr, return; } + /* + * SSO (SAO) ordering is supported on KVM and thread=single hosts, + * but not MTTCG, so disable it. To advertise it, a cap would have + * to be added, or support implemented for MTTCG. + */ + if (ppc_hash64_has(cpu, PPC_HASH64_CI_LARGEPAGE)) { /* * Note: we keep CI large pages off by default because a 64K capable
SAO is a page table attribute that strengthens the memory ordering of accesses. QEMU with MTTCG does not implement this, so clear it in ibm,pa-features. This is an obscure feature that has been removed from POWER10 ISA v3.1, there isn't much concern with removing it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- hw/ppc/pnv.c | 2 +- hw/ppc/spapr.c | 14 ++++++++++---- 2 files changed, 11 insertions(+), 5 deletions(-)