target/riscv: Support the Virtual Instruction fault

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 4c744dce9b0b057cbb5cc0f4d4ac75cda682a8af.1597259519.git.alistair.francis@wdc.com
Message-Id: <4c744dce9b0b057cbb5cc0f4d4ac75cda682a8af.1597259519.git.alistair.francis@wdc.com>

target/riscv/cpu_bits.h

@@ -461,6 +461,11 @@
 #define HSTATUS_WPRI HSTATUS64_WPRI
 #endif
 
+#define HCOUNTEREN_CY        (1 << 0)
+#define HCOUNTEREN_TM        (1 << 1)
+#define HCOUNTEREN_IR        (1 << 2)
+#define HCOUNTEREN_HPM3      (1 << 3)
+
 /* Privilege modes */
 #define PRV_U 0
 #define PRV_S 1
@@ -553,6 +558,7 @@
 #define RISCV_EXCP_STORE_PAGE_FAULT              0xf /* since: priv-1.10.0 */
 #define RISCV_EXCP_INST_GUEST_PAGE_FAULT         0x14
 #define RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT       0x15
+#define RISCV_EXCP_VIRT_INSTRUCTION_FAULT        0x16
 #define RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT  0x17
 
 #define RISCV_EXCP_INT_FLAG                0x80000000

target/riscv/csr.c

@@ -75,6 +75,61 @@ static int ctr(CPURISCVState *env, int csrno)
         /* The Counters extensions is not enabled */
         return -RISCV_EXCP_ILLEGAL_INST;
     }
+
+    if (riscv_cpu_virt_enabled(env)) {
+        switch (csrno) {
+        case CSR_CYCLE:
+            if (!get_field(env->hcounteren, HCOUNTEREN_CY) &&
+                get_field(env->mcounteren, HCOUNTEREN_CY)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_TIME:
+            if (!get_field(env->hcounteren, HCOUNTEREN_TM) &&
+                get_field(env->mcounteren, HCOUNTEREN_TM)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_INSTRET:
+            if (!get_field(env->hcounteren, HCOUNTEREN_IR) &&
+                get_field(env->mcounteren, HCOUNTEREN_IR)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_HPMCOUNTER3...CSR_HPMCOUNTER31:
+            if (!get_field(env->hcounteren, 1 << (csrno - CSR_HPMCOUNTER3)) &&
+                get_field(env->mcounteren, 1 << (csrno - CSR_HPMCOUNTER3))) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+#if defined(TARGET_RISCV32)
+        case CSR_CYCLEH:
+            if (!get_field(env->hcounteren, HCOUNTEREN_CY) &&
+                get_field(env->mcounteren, HCOUNTEREN_CY)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_TIMEH:
+            if (!get_field(env->hcounteren, HCOUNTEREN_TM) &&
+                get_field(env->mcounteren, HCOUNTEREN_TM)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_INSTRETH:
+            if (!get_field(env->hcounteren, HCOUNTEREN_IR) &&
+                get_field(env->mcounteren, HCOUNTEREN_IR)) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+        case CSR_HPMCOUNTER3H...CSR_HPMCOUNTER31H:
+            if (!get_field(env->hcounteren, 1 << (csrno - CSR_HPMCOUNTER3H)) &&
+                get_field(env->mcounteren, 1 << (csrno - CSR_HPMCOUNTER3H))) {
+                return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+            }
+            break;
+#endif
+        }
+    }
 #endif
     return 0;
 }
@@ -98,6 +153,8 @@ static int hmode(CPURISCVState *env, int csrno)
         if ((env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
             env->priv == PRV_M) {
             return 0;
+        } else {
+            return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
         }
     }
 
@@ -340,6 +397,7 @@ static const target_ulong delegable_excps =
     (1ULL << (RISCV_EXCP_STORE_PAGE_FAULT)) |
     (1ULL << (RISCV_EXCP_INST_GUEST_PAGE_FAULT)) |
     (1ULL << (RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT)) |
+    (1ULL << (RISCV_EXCP_VIRT_INSTRUCTION_FAULT)) |
     (1ULL << (RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT));
 static const target_ulong sstatus_v1_10_mask = SSTATUS_SIE | SSTATUS_SPIE |
     SSTATUS_UIE | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS |
@@ -1238,9 +1296,13 @@ int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
     }
 
     /* check predicate */
-    if (!csr_ops[csrno].predicate || csr_ops[csrno].predicate(env, csrno) < 0) {
+    if (!csr_ops[csrno].predicate) {
         return -RISCV_EXCP_ILLEGAL_INST;
     }
+    ret = csr_ops[csrno].predicate(env, csrno);
+    if (ret < 0) {
+        return ret;
+    }
 
     /* execute combined read/write operation if it exists */
     if (csr_ops[csrno].op) {

target/riscv/helper.h

@@ -80,6 +80,7 @@ DEF_HELPER_1(tlb_flush, void, env)
 /* Hypervisor functions */
 #ifndef CONFIG_USER_ONLY
 DEF_HELPER_1(hyp_tlb_flush, void, env)
+DEF_HELPER_1(hyp_gvma_tlb_flush, void, env)
 DEF_HELPER_4(hyp_load, tl, env, tl, tl, tl)
 DEF_HELPER_5(hyp_store, void, env, tl, tl, tl, tl)
 DEF_HELPER_4(hyp_x_load, tl, env, tl, tl, tl)

target/riscv/insn_trans/trans_rvh.c.inc

@@ -360,7 +360,7 @@ static bool trans_hfence_gvma(DisasContext *ctx, arg_sfence_vma *a)
 {
     REQUIRE_EXT(ctx, RVH);
 #ifndef CONFIG_USER_ONLY
-    gen_helper_hyp_tlb_flush(cpu_env);
+    gen_helper_hyp_gvma_tlb_flush(cpu_env);
     return true;
 #endif
     return false;

target/riscv/op_helper.c

@@ -94,6 +94,11 @@ target_ulong helper_sret(CPURISCVState *env, target_ulong cpu_pc_deb)
         riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
     }
 
+    if (riscv_has_ext(env, RVH) && riscv_cpu_virt_enabled(env) &&
+        get_field(env->hstatus, HSTATUS_VTSR)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
+    }
+
     mstatus = env->mstatus;
 
     if (riscv_has_ext(env, RVH) && !riscv_cpu_virt_enabled(env)) {
@@ -176,7 +181,7 @@ void helper_wfi(CPURISCVState *env)
     if ((env->priv == PRV_S &&
         get_field(env->mstatus, MSTATUS_TW)) ||
         riscv_cpu_virt_enabled(env)) {
-        riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
     } else {
         cs->halted = 1;
         cs->exception_index = EXCP_HLT;
@@ -191,6 +196,9 @@ void helper_tlb_flush(CPURISCVState *env)
         (env->priv == PRV_S &&
          get_field(env->mstatus, MSTATUS_TVM))) {
         riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    } else if (riscv_has_ext(env, RVH) && riscv_cpu_virt_enabled(env) &&
+               get_field(env->hstatus, HSTATUS_VTVM)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
     } else {
         tlb_flush(cs);
     }
@@ -200,6 +208,10 @@ void helper_hyp_tlb_flush(CPURISCVState *env)
 {
     CPUState *cs = env_cpu(env);
 
+    if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
+    }
+
     if (env->priv == PRV_M ||
         (env->priv == PRV_S && !riscv_cpu_virt_enabled(env))) {
         tlb_flush(cs);
@@ -209,6 +221,16 @@ void helper_hyp_tlb_flush(CPURISCVState *env)
     riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
 }
 
+void helper_hyp_gvma_tlb_flush(CPURISCVState *env)
+{
+    if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env) &&
+        get_field(env->mstatus, MSTATUS_TVM)) {
+        riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    }
+
+    helper_hyp_tlb_flush(env);
+}
+
 target_ulong helper_hyp_load(CPURISCVState *env, target_ulong address,
                              target_ulong attrs, target_ulong memop)
 {
@@ -251,7 +273,11 @@ target_ulong helper_hyp_load(CPURISCVState *env, target_ulong address,
         return pte;
     }
 
-    riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    if (riscv_cpu_virt_enabled(env)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
+    } else {
+        riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    }
     return 0;
 }
 
@@ -289,7 +315,11 @@ void helper_hyp_store(CPURISCVState *env, target_ulong address,
         return;
     }
 
-    riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    if (riscv_cpu_virt_enabled(env)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
+    } else {
+        riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    }
 }
 
 target_ulong helper_hyp_x_load(CPURISCVState *env, target_ulong address,
@@ -319,7 +349,11 @@ target_ulong helper_hyp_x_load(CPURISCVState *env, target_ulong address,
         return pte;
     }
 
-    riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    if (riscv_cpu_virt_enabled(env)) {
+        riscv_raise_exception(env, RISCV_EXCP_VIRT_INSTRUCTION_FAULT, GETPC());
+    } else {
+        riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
+    }
     return 0;
 }