[PATCH v6 16/25] target/riscv: Set MMU_2STAGE_BIT in riscv_cpu_mmu_index

[Richard Henderson]

Incorporate the virt_enabled and MPV checks into the cpu_mmu_index
function, so we don't have to keep doing it within tlb_fill and
subroutines.  This also elides a flush on changes to MPV.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/riscv/cpu_helper.c | 50 +++++++++++++--------------------------
 target/riscv/csr.c        |  6 +----
 2 files changed, 18 insertions(+), 38 deletions(-)

diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 0adfd4a12b..6c42f9c6fd 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -37,19 +37,21 @@ int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
 #ifdef CONFIG_USER_ONLY
     return 0;
 #else
-    if (ifetch) {
-        return env->priv;
-    }
+    bool virt = riscv_cpu_virt_enabled(env);
+    int mode = env->priv;
 
     /* All priv -> mmu_idx mapping are here */
-    int mode = env->priv;
-    if (mode == PRV_M && get_field(env->mstatus, MSTATUS_MPRV)) {
-        mode = get_field(env->mstatus, MSTATUS_MPP);
+    if (!ifetch) {
+        if (mode == PRV_M && get_field(env->mstatus, MSTATUS_MPRV)) {
+            mode = get_field(env->mstatus, MSTATUS_MPP);
+            virt = get_field(env->mstatus, MSTATUS_MPV);
+        }
+        if (mode == PRV_S && get_field(env->mstatus, MSTATUS_SUM)) {
+            mode = MMUIdx_S_SUM;
+        }
     }
-    if (mode == PRV_S && get_field(env->mstatus, MSTATUS_SUM)) {
-        return MMUIdx_S_SUM;
-    }
-    return mode;
+
+    return mode | (virt ? MMU_2STAGE_BIT : 0);
 #endif
 }
 
@@ -1165,8 +1167,7 @@ void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr 
physaddr,
     }
 
     env->badaddr = addr;
-    env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
-                            mmuidx_2stage(mmu_idx);
+    env->two_stage_lookup = mmuidx_2stage(mmu_idx);
     env->two_stage_indirect_lookup = false;
     cpu_loop_exit_restore(cs, retaddr);
 }
@@ -1191,8 +1192,7 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr 
addr,
         g_assert_not_reached();
     }
     env->badaddr = addr;
-    env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
-                            mmuidx_2stage(mmu_idx);
+    env->two_stage_lookup = mmuidx_2stage(mmu_idx);
     env->two_stage_indirect_lookup = false;
     cpu_loop_exit_restore(cs, retaddr);
 }
@@ -1230,7 +1230,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int 
size,
     int prot, prot2, prot_pmp;
     bool pmp_violation = false;
     bool first_stage_error = true;
-    bool two_stage_lookup = false;
+    bool two_stage_lookup = mmuidx_2stage(mmu_idx);
     bool two_stage_indirect_error = false;
     int ret = TRANSLATE_FAIL;
     int mode = mmu_idx;
@@ -1242,22 +1242,8 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int 
size,
     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
                   __func__, address, access_type, mmu_idx);
 
-    /* MPRV does not affect the virtual-machine load/store
-       instructions, HLV, HLVX, and HSV. */
-    if (mmuidx_2stage(mmu_idx)) {
-        ;
-    } else if (mode == PRV_M && access_type != MMU_INST_FETCH &&
-               get_field(env->mstatus, MSTATUS_MPRV)) {
-        mode = get_field(env->mstatus, MSTATUS_MPP);
-        if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) {
-            two_stage_lookup = true;
-        }
-    }
-
     pmu_tlb_fill_incr_ctr(cpu, access_type);
-    if (riscv_cpu_virt_enabled(env) ||
-        ((mmuidx_2stage(mmu_idx) || two_stage_lookup) &&
-         access_type != MMU_INST_FETCH)) {
+    if (two_stage_lookup) {
         /* Two stage lookup */
         ret = get_physical_address(env, &pa, &prot, address,
                                    &env->guest_phys_fault_addr, access_type,
@@ -1352,9 +1338,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int 
size,
         return false;
     } else {
         raise_mmu_exception(env, address, access_type, pmp_violation,
-                            first_stage_error,
-                            riscv_cpu_virt_enabled(env) ||
-                                mmuidx_2stage(mmu_idx),
+                            first_stage_error, two_stage_lookup,
                             two_stage_indirect_error);
         cpu_loop_exit_restore(cs, retaddr);
     }
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index b79758a606..1b635373c6 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -1246,7 +1246,7 @@ static RISCVException write_mstatus(CPURISCVState *env, 
int csrno,
     RISCVMXL xl = riscv_cpu_mxl(env);
 
     /* flush tlb on mstatus fields that affect VM */
-    if ((val ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPV)) {
+    if ((val ^ mstatus) & MSTATUS_MXR) {
         tlb_flush(env_cpu(env));
     }
     mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
@@ -1294,10 +1294,6 @@ static RISCVException write_mstatush(CPURISCVState *env, 
int csrno,
     uint64_t valh = (uint64_t)val << 32;
     uint64_t mask = MSTATUS_MPV | MSTATUS_GVA;
 
-    if ((valh ^ env->mstatus) & (MSTATUS_MPV)) {
-        tlb_flush(env_cpu(env));
-    }
-
     env->mstatus = (env->mstatus & ~mask) | (valh & mask);
 
     return RISCV_EXCP_NONE;
-- 
2.34.1