[v6,11/18] target/ppc: Only calculate RMLS derived RMA limit on demand
diff mbox series

Message ID 20200224233724.46415-12-david@gibson.dropbear.id.au
State New
Headers show
Series
  • [v6,01/18] pseries: Update SLOF firmware image
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Commit Message

David Gibson Feb. 24, 2020, 11:37 p.m. UTC
When the LPCR is written, we update the env->rmls field with the RMA limit
it implies.  Simplify things by just calculating the value directly from
the LPCR value when we need it.

It's possible this is a little slower, but it's unlikely to be significant,
since this is only for real mode accesses in a translation configuration
that's not used very often, and the whole thing is behind the qemu TLB
anyway.  Therefore, keeping the number of state variables down and not
having to worry about making sure it's always in sync seems the better
option.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
---
 target/ppc/cpu.h        |  1 -
 target/ppc/mmu-hash64.c | 84 ++++++++++++++++++++---------------------
 2 files changed, 40 insertions(+), 45 deletions(-)

Comments

Greg Kurz Feb. 26, 2020, 1:24 p.m. UTC | #1
On Tue, 25 Feb 2020 10:37:17 +1100
David Gibson <david@gibson.dropbear.id.au> wrote:

> When the LPCR is written, we update the env->rmls field with the RMA limit
> it implies.  Simplify things by just calculating the value directly from
> the LPCR value when we need it.
> 
> It's possible this is a little slower, but it's unlikely to be significant,
> since this is only for real mode accesses in a translation configuration
> that's not used very often, and the whole thing is behind the qemu TLB
> anyway.  Therefore, keeping the number of state variables down and not
> having to worry about making sure it's always in sync seems the better
> option.
> 

This patch also refactors the code of ppc_hash64_update_vrma(), which
is definitely an improvement, but seems a bit unrelated to the title...
I'd personally make it a separate patch but you decide of course :)

Also, a cosmetic remark. See below.

> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> Reviewed-by: Cédric Le Goater <clg@kaod.org>
> ---
>  target/ppc/cpu.h        |  1 -
>  target/ppc/mmu-hash64.c | 84 ++++++++++++++++++++---------------------
>  2 files changed, 40 insertions(+), 45 deletions(-)
> 
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index 8077fdb068..f9871b1233 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -1046,7 +1046,6 @@ struct CPUPPCState {
>      uint64_t insns_flags2;
>  #if defined(TARGET_PPC64)
>      ppc_slb_t vrma_slb;
> -    target_ulong rmls;
>  #endif
>  
>      int error_code;
> diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c
> index dd0df6fd01..ac21c14f68 100644
> --- a/target/ppc/mmu-hash64.c
> +++ b/target/ppc/mmu-hash64.c
> @@ -791,6 +791,35 @@ static target_ulong rmls_limit(PowerPCCPU *cpu)
>      }
>  }
>  
> +static int build_vrma_slbe(PowerPCCPU *cpu, ppc_slb_t *slb)
> +{
> +    CPUPPCState *env = &cpu->env;
> +    target_ulong lpcr = env->spr[SPR_LPCR];
> +    uint32_t vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
> +    target_ulong vsid = SLB_VSID_VRMA | ((vrmasd << 4) & SLB_VSID_LLP_MASK);
> +    int i;
> +
> +    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
> +        const PPCHash64SegmentPageSizes *sps = &cpu->hash64_opts->sps[i];
> +
> +        if (!sps->page_shift) {
> +            break;
> +        }
> +
> +        if ((vsid & SLB_VSID_LLP_MASK) == sps->slb_enc) {
> +            slb->esid = SLB_ESID_V;
> +            slb->vsid = vsid;
> +            slb->sps = sps;
> +            return 0;
> +        }
> +    }
> +
> +    error_report("Bad page size encoding in LPCR[VRMASD]; LPCR=0x"
> +                 TARGET_FMT_lx"\n", lpcr);
> +
> +    return -1;
> +}
> +
>  int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
>                                  int rwx, int mmu_idx)
>  {
> @@ -844,8 +873,10 @@ int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
>  
>              goto skip_slb_search;
>          } else {
> +            target_ulong limit = rmls_limit(cpu);
> +
>              /* Emulated old-style RMO mode, bounds check against RMLS */
> -            if (raddr >= env->rmls) {
> +            if (raddr >= limit) {
>                  if (rwx == 2) {
>                      ppc_hash64_set_isi(cs, SRR1_PROTFAULT);
>                  } else {
> @@ -1007,8 +1038,9 @@ hwaddr ppc_hash64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong addr)
>                  return -1;
>              }
>          } else {
> +            target_ulong limit = rmls_limit(cpu);

Maybe add an empty line like you did above for consistency and better
readability ?

Anyway, feel free to add:

Reviewed-by: Greg Kurz <groug@kaod.org>

>              /* Emulated old-style RMO mode, bounds check against RMLS */
> -            if (raddr >= env->rmls) {
> +            if (raddr >= limit) {
>                  return -1;
>              }
>              return raddr | env->spr[SPR_RMOR];
> @@ -1043,53 +1075,18 @@ void ppc_hash64_tlb_flush_hpte(PowerPCCPU *cpu, target_ulong ptex,
>  static void ppc_hash64_update_vrma(PowerPCCPU *cpu)
>  {
>      CPUPPCState *env = &cpu->env;
> -    const PPCHash64SegmentPageSizes *sps = NULL;
> -    target_ulong esid, vsid, lpcr;
>      ppc_slb_t *slb = &env->vrma_slb;
> -    uint32_t vrmasd;
> -    int i;
> -
> -    /* First clear it */
> -    slb->esid = slb->vsid = 0;
> -    slb->sps = NULL;
>  
>      /* Is VRMA enabled ? */
> -    if (!ppc_hash64_use_vrma(env)) {
> -        return;
> -    }
> -
> -    /*
> -     * Make one up. Mostly ignore the ESID which will not be needed
> -     * for translation
> -     */
> -    lpcr = env->spr[SPR_LPCR];
> -    vsid = SLB_VSID_VRMA;
> -    vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
> -    vsid |= (vrmasd << 4) & (SLB_VSID_L | SLB_VSID_LP);
> -    esid = SLB_ESID_V;
> -
> -    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
> -        const PPCHash64SegmentPageSizes *sps1 = &cpu->hash64_opts->sps[i];
> -
> -        if (!sps1->page_shift) {
> -            break;
> +    if (ppc_hash64_use_vrma(env)) {
> +        if (build_vrma_slbe(cpu, slb) == 0) {
> +            return;
>          }
> -
> -        if ((vsid & SLB_VSID_LLP_MASK) == sps1->slb_enc) {
> -            sps = sps1;
> -            break;
> -        }
> -    }
> -
> -    if (!sps) {
> -        error_report("Bad page size encoding esid 0x"TARGET_FMT_lx
> -                     " vsid 0x"TARGET_FMT_lx, esid, vsid);
> -        return;
>      }
>  
> -    slb->vsid = vsid;
> -    slb->esid = esid;
> -    slb->sps = sps;
> +    /* Otherwise, clear it to indicate error */
> +    slb->esid = slb->vsid = 0;
> +    slb->sps = NULL;
>  }
>  
>  void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
> @@ -1098,7 +1095,6 @@ void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
>      CPUPPCState *env = &cpu->env;
>  
>      env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
> -    env->rmls = rmls_limit(cpu);
>      ppc_hash64_update_vrma(cpu);
>  }
>
David Gibson Feb. 27, 2020, 4:33 a.m. UTC | #2
On Wed, Feb 26, 2020 at 02:24:53PM +0100, Greg Kurz wrote:
> On Tue, 25 Feb 2020 10:37:17 +1100
> David Gibson <david@gibson.dropbear.id.au> wrote:
> 
> > When the LPCR is written, we update the env->rmls field with the RMA limit
> > it implies.  Simplify things by just calculating the value directly from
> > the LPCR value when we need it.
> > 
> > It's possible this is a little slower, but it's unlikely to be significant,
> > since this is only for real mode accesses in a translation configuration
> > that's not used very often, and the whole thing is behind the qemu TLB
> > anyway.  Therefore, keeping the number of state variables down and not
> > having to worry about making sure it's always in sync seems the better
> > option.
> > 
> 
> This patch also refactors the code of ppc_hash64_update_vrma(), which
> is definitely an improvement, but seems a bit unrelated to the title...
> I'd personally make it a separate patch but you decide of course :)

Ah, dang it, botched rebase damage.  There are a couple of hunks here
that are supposed to be in the next patch.  I think I've sorted it out
now.

> 
> Also, a cosmetic remark. See below.
> 
> > Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> > Reviewed-by: Cédric Le Goater <clg@kaod.org>
> > ---
> >  target/ppc/cpu.h        |  1 -
> >  target/ppc/mmu-hash64.c | 84 ++++++++++++++++++++---------------------
> >  2 files changed, 40 insertions(+), 45 deletions(-)
> > 
> > diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> > index 8077fdb068..f9871b1233 100644
> > --- a/target/ppc/cpu.h
> > +++ b/target/ppc/cpu.h
> > @@ -1046,7 +1046,6 @@ struct CPUPPCState {
> >      uint64_t insns_flags2;
> >  #if defined(TARGET_PPC64)
> >      ppc_slb_t vrma_slb;
> > -    target_ulong rmls;
> >  #endif
> >  
> >      int error_code;
> > diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c
> > index dd0df6fd01..ac21c14f68 100644
> > --- a/target/ppc/mmu-hash64.c
> > +++ b/target/ppc/mmu-hash64.c
> > @@ -791,6 +791,35 @@ static target_ulong rmls_limit(PowerPCCPU *cpu)
> >      }
> >  }
> >  
> > +static int build_vrma_slbe(PowerPCCPU *cpu, ppc_slb_t *slb)
> > +{
> > +    CPUPPCState *env = &cpu->env;
> > +    target_ulong lpcr = env->spr[SPR_LPCR];
> > +    uint32_t vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
> > +    target_ulong vsid = SLB_VSID_VRMA | ((vrmasd << 4) & SLB_VSID_LLP_MASK);
> > +    int i;
> > +
> > +    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
> > +        const PPCHash64SegmentPageSizes *sps = &cpu->hash64_opts->sps[i];
> > +
> > +        if (!sps->page_shift) {
> > +            break;
> > +        }
> > +
> > +        if ((vsid & SLB_VSID_LLP_MASK) == sps->slb_enc) {
> > +            slb->esid = SLB_ESID_V;
> > +            slb->vsid = vsid;
> > +            slb->sps = sps;
> > +            return 0;
> > +        }
> > +    }
> > +
> > +    error_report("Bad page size encoding in LPCR[VRMASD]; LPCR=0x"
> > +                 TARGET_FMT_lx"\n", lpcr);
> > +
> > +    return -1;
> > +}
> > +
> >  int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
> >                                  int rwx, int mmu_idx)
> >  {
> > @@ -844,8 +873,10 @@ int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
> >  
> >              goto skip_slb_search;
> >          } else {
> > +            target_ulong limit = rmls_limit(cpu);
> > +
> >              /* Emulated old-style RMO mode, bounds check against RMLS */
> > -            if (raddr >= env->rmls) {
> > +            if (raddr >= limit) {
> >                  if (rwx == 2) {
> >                      ppc_hash64_set_isi(cs, SRR1_PROTFAULT);
> >                  } else {
> > @@ -1007,8 +1038,9 @@ hwaddr ppc_hash64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong addr)
> >                  return -1;
> >              }
> >          } else {
> > +            target_ulong limit = rmls_limit(cpu);
> 
> Maybe add an empty line like you did above for consistency and better
> readability ?

Ok, done.

> 
> Anyway, feel free to add:
> 
> Reviewed-by: Greg Kurz <groug@kaod.org>
> 
> >              /* Emulated old-style RMO mode, bounds check against RMLS */
> > -            if (raddr >= env->rmls) {
> > +            if (raddr >= limit) {
> >                  return -1;
> >              }
> >              return raddr | env->spr[SPR_RMOR];
> > @@ -1043,53 +1075,18 @@ void ppc_hash64_tlb_flush_hpte(PowerPCCPU *cpu, target_ulong ptex,
> >  static void ppc_hash64_update_vrma(PowerPCCPU *cpu)
> >  {
> >      CPUPPCState *env = &cpu->env;
> > -    const PPCHash64SegmentPageSizes *sps = NULL;
> > -    target_ulong esid, vsid, lpcr;
> >      ppc_slb_t *slb = &env->vrma_slb;
> > -    uint32_t vrmasd;
> > -    int i;
> > -
> > -    /* First clear it */
> > -    slb->esid = slb->vsid = 0;
> > -    slb->sps = NULL;
> >  
> >      /* Is VRMA enabled ? */
> > -    if (!ppc_hash64_use_vrma(env)) {
> > -        return;
> > -    }
> > -
> > -    /*
> > -     * Make one up. Mostly ignore the ESID which will not be needed
> > -     * for translation
> > -     */
> > -    lpcr = env->spr[SPR_LPCR];
> > -    vsid = SLB_VSID_VRMA;
> > -    vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
> > -    vsid |= (vrmasd << 4) & (SLB_VSID_L | SLB_VSID_LP);
> > -    esid = SLB_ESID_V;
> > -
> > -    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
> > -        const PPCHash64SegmentPageSizes *sps1 = &cpu->hash64_opts->sps[i];
> > -
> > -        if (!sps1->page_shift) {
> > -            break;
> > +    if (ppc_hash64_use_vrma(env)) {
> > +        if (build_vrma_slbe(cpu, slb) == 0) {
> > +            return;
> >          }
> > -
> > -        if ((vsid & SLB_VSID_LLP_MASK) == sps1->slb_enc) {
> > -            sps = sps1;
> > -            break;
> > -        }
> > -    }
> > -
> > -    if (!sps) {
> > -        error_report("Bad page size encoding esid 0x"TARGET_FMT_lx
> > -                     " vsid 0x"TARGET_FMT_lx, esid, vsid);
> > -        return;
> >      }
> >  
> > -    slb->vsid = vsid;
> > -    slb->esid = esid;
> > -    slb->sps = sps;
> > +    /* Otherwise, clear it to indicate error */
> > +    slb->esid = slb->vsid = 0;
> > +    slb->sps = NULL;
> >  }
> >  
> >  void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
> > @@ -1098,7 +1095,6 @@ void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
> >      CPUPPCState *env = &cpu->env;
> >  
> >      env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
> > -    env->rmls = rmls_limit(cpu);
> >      ppc_hash64_update_vrma(cpu);
> >  }
> >  
>

Patch
diff mbox series

diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index 8077fdb068..f9871b1233 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -1046,7 +1046,6 @@  struct CPUPPCState {
     uint64_t insns_flags2;
 #if defined(TARGET_PPC64)
     ppc_slb_t vrma_slb;
-    target_ulong rmls;
 #endif
 
     int error_code;
diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c
index dd0df6fd01..ac21c14f68 100644
--- a/target/ppc/mmu-hash64.c
+++ b/target/ppc/mmu-hash64.c
@@ -791,6 +791,35 @@  static target_ulong rmls_limit(PowerPCCPU *cpu)
     }
 }
 
+static int build_vrma_slbe(PowerPCCPU *cpu, ppc_slb_t *slb)
+{
+    CPUPPCState *env = &cpu->env;
+    target_ulong lpcr = env->spr[SPR_LPCR];
+    uint32_t vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
+    target_ulong vsid = SLB_VSID_VRMA | ((vrmasd << 4) & SLB_VSID_LLP_MASK);
+    int i;
+
+    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
+        const PPCHash64SegmentPageSizes *sps = &cpu->hash64_opts->sps[i];
+
+        if (!sps->page_shift) {
+            break;
+        }
+
+        if ((vsid & SLB_VSID_LLP_MASK) == sps->slb_enc) {
+            slb->esid = SLB_ESID_V;
+            slb->vsid = vsid;
+            slb->sps = sps;
+            return 0;
+        }
+    }
+
+    error_report("Bad page size encoding in LPCR[VRMASD]; LPCR=0x"
+                 TARGET_FMT_lx"\n", lpcr);
+
+    return -1;
+}
+
 int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
                                 int rwx, int mmu_idx)
 {
@@ -844,8 +873,10 @@  int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
 
             goto skip_slb_search;
         } else {
+            target_ulong limit = rmls_limit(cpu);
+
             /* Emulated old-style RMO mode, bounds check against RMLS */
-            if (raddr >= env->rmls) {
+            if (raddr >= limit) {
                 if (rwx == 2) {
                     ppc_hash64_set_isi(cs, SRR1_PROTFAULT);
                 } else {
@@ -1007,8 +1038,9 @@  hwaddr ppc_hash64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong addr)
                 return -1;
             }
         } else {
+            target_ulong limit = rmls_limit(cpu);
             /* Emulated old-style RMO mode, bounds check against RMLS */
-            if (raddr >= env->rmls) {
+            if (raddr >= limit) {
                 return -1;
             }
             return raddr | env->spr[SPR_RMOR];
@@ -1043,53 +1075,18 @@  void ppc_hash64_tlb_flush_hpte(PowerPCCPU *cpu, target_ulong ptex,
 static void ppc_hash64_update_vrma(PowerPCCPU *cpu)
 {
     CPUPPCState *env = &cpu->env;
-    const PPCHash64SegmentPageSizes *sps = NULL;
-    target_ulong esid, vsid, lpcr;
     ppc_slb_t *slb = &env->vrma_slb;
-    uint32_t vrmasd;
-    int i;
-
-    /* First clear it */
-    slb->esid = slb->vsid = 0;
-    slb->sps = NULL;
 
     /* Is VRMA enabled ? */
-    if (!ppc_hash64_use_vrma(env)) {
-        return;
-    }
-
-    /*
-     * Make one up. Mostly ignore the ESID which will not be needed
-     * for translation
-     */
-    lpcr = env->spr[SPR_LPCR];
-    vsid = SLB_VSID_VRMA;
-    vrmasd = (lpcr & LPCR_VRMASD) >> LPCR_VRMASD_SHIFT;
-    vsid |= (vrmasd << 4) & (SLB_VSID_L | SLB_VSID_LP);
-    esid = SLB_ESID_V;
-
-    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
-        const PPCHash64SegmentPageSizes *sps1 = &cpu->hash64_opts->sps[i];
-
-        if (!sps1->page_shift) {
-            break;
+    if (ppc_hash64_use_vrma(env)) {
+        if (build_vrma_slbe(cpu, slb) == 0) {
+            return;
         }
-
-        if ((vsid & SLB_VSID_LLP_MASK) == sps1->slb_enc) {
-            sps = sps1;
-            break;
-        }
-    }
-
-    if (!sps) {
-        error_report("Bad page size encoding esid 0x"TARGET_FMT_lx
-                     " vsid 0x"TARGET_FMT_lx, esid, vsid);
-        return;
     }
 
-    slb->vsid = vsid;
-    slb->esid = esid;
-    slb->sps = sps;
+    /* Otherwise, clear it to indicate error */
+    slb->esid = slb->vsid = 0;
+    slb->sps = NULL;
 }
 
 void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
@@ -1098,7 +1095,6 @@  void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
     CPUPPCState *env = &cpu->env;
 
     env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
-    env->rmls = rmls_limit(cpu);
     ppc_hash64_update_vrma(cpu);
 }