target/riscv: Extend the MIE CSR to support virtulisation

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index c0e942684dbe9b27fed6d7be9fa4eef8d9a1e18e..918678789af833c82edce7f369f3bf9f3e8764db 100644 (file)
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -244,8 +244,10 @@ static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
 #define S_MODE_INTERRUPTS  (MIP_SSIP | MIP_STIP | MIP_SEIP)
 #define VS_MODE_INTERRUPTS (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP)
 
-static const target_ulong delegable_ints = S_MODE_INTERRUPTS;
-static const target_ulong all_ints = M_MODE_INTERRUPTS | S_MODE_INTERRUPTS;
+static const target_ulong delegable_ints = S_MODE_INTERRUPTS |
+                                           VS_MODE_INTERRUPTS;
+static const target_ulong all_ints = M_MODE_INTERRUPTS | S_MODE_INTERRUPTS |
+                                     VS_MODE_INTERRUPTS;
 static const target_ulong delegable_excps =
     (1ULL << (RISCV_EXCP_INST_ADDR_MIS)) |
     (1ULL << (RISCV_EXCP_INST_ACCESS_FAULT)) |
@@ -630,13 +632,27 @@ static int write_sstatus(CPURISCVState *env, int csrno, target_ulong val)
 
 static int read_sie(CPURISCVState *env, int csrno, target_ulong *val)
 {
-    *val = env->mie & env->mideleg;
+    if (riscv_cpu_virt_enabled(env)) {
+        /* Tell the guest the VS bits, shifted to the S bit locations */
+        *val = (env->mie & env->mideleg & VS_MODE_INTERRUPTS) >> 1;
+    } else {
+        *val = env->mie & env->mideleg;
+    }
     return 0;
 }
 
 static int write_sie(CPURISCVState *env, int csrno, target_ulong val)
 {
-    target_ulong newval = (env->mie & ~env->mideleg) | (val & env->mideleg);
+    target_ulong newval;
+
+    if (riscv_cpu_virt_enabled(env)) {
+        /* Shift the guests S bits to VS */
+        newval = (env->mie & ~VS_MODE_INTERRUPTS) |
+                 ((val << 1) & VS_MODE_INTERRUPTS);
+    } else {
+        newval = (env->mie & ~S_MODE_INTERRUPTS) | (val & S_MODE_INTERRUPTS);
+    }
+
     return write_mie(env, CSR_MIE, newval);
 }