target/ppc: Don't store VRMA SLBE persistently

Currently, we construct the SLBE used for VRMA translations when the LPCR
is written (which controls some bits in the SLBE), then use it later for
translations.

This is a bit complex and confusing - simplify it by simply constructing
the SLBE directly from the LPCR when we need it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

target/ppc/cpu.h

@@ -1044,9 +1044,6 @@ struct CPUPPCState {
     uint32_t flags;
     uint64_t insns_flags;
     uint64_t insns_flags2;
-#if defined(TARGET_PPC64)
-    ppc_slb_t vrma_slb;
-#endif
 
     int error_code;
     uint32_t pending_interrupts;

target/ppc/mmu-hash64.c

@@ -784,11 +784,41 @@ static target_ulong rmls_limit(PowerPCCPU *cpu)
     return rma_sizes[rmls];
 }
 
+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)
 {
     CPUState *cs = CPU(cpu);
     CPUPPCState *env = &cpu->env;
+    ppc_slb_t vrma_slbe;
     ppc_slb_t *slb;
     unsigned apshift;
     hwaddr ptex;
@@ -827,8 +857,8 @@ int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
             }
         } else if (ppc_hash64_use_vrma(env)) {
             /* Emulated VRMA mode */
-            slb = &env->vrma_slb;
-            if (!slb->sps) {
+            slb = &vrma_slbe;
+            if (build_vrma_slbe(cpu, slb) != 0) {
                 /* Invalid VRMA setup, machine check */
                 cs->exception_index = POWERPC_EXCP_MCHECK;
                 env->error_code = 0;
@@ -976,6 +1006,7 @@ int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
 hwaddr ppc_hash64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong addr)
 {
     CPUPPCState *env = &cpu->env;
+    ppc_slb_t vrma_slbe;
     ppc_slb_t *slb;
     hwaddr ptex, raddr;
     ppc_hash_pte64_t pte;
@@ -997,8 +1028,8 @@ hwaddr ppc_hash64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong addr)
             return raddr | env->spr[SPR_HRMOR];
         } else if (ppc_hash64_use_vrma(env)) {
             /* Emulated VRMA mode */
-            slb = &env->vrma_slb;
-            if (!slb->sps) {
+            slb = &vrma_slbe;
+            if (build_vrma_slbe(cpu, slb) != 0) {
                 return -1;
             }
         } else {
@@ -1037,65 +1068,12 @@ void ppc_hash64_tlb_flush_hpte(PowerPCCPU *cpu, target_ulong ptex,
     cpu->env.tlb_need_flush = TLB_NEED_GLOBAL_FLUSH | TLB_NEED_LOCAL_FLUSH;
 }
 
-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 ((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;
-}
-
 void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
 {
     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
     CPUPPCState *env = &cpu->env;
 
     env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
-    ppc_hash64_update_vrma(cpu);
 }
 
 void helper_store_lpcr(CPUPPCState *env, target_ulong val)