target/riscv: Add Hypervisor CSR access functions

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

1 files changed, 134 insertions, 2 deletions

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index c63b2f980c..bee639e92e 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -98,6 +98,20 @@ static int smode(CPURISCVState *env, int csrno)
     return -!riscv_has_ext(env, RVS);
 }
 
+static int hmode(CPURISCVState *env, int csrno)
+{
+    if (riscv_has_ext(env, RVS) &&
+        riscv_has_ext(env, RVH)) {
+        /* Hypervisor extension is supported */
+        if ((env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
+            env->priv == PRV_M) {
+            return 0;
+        }
+    }
+
+    return -1;
+}
+
 static int pmp(CPURISCVState *env, int csrno)
 {
     return -!riscv_feature(env, RISCV_FEATURE_PMP);
@@ -226,8 +240,9 @@ static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
 
 /* Machine constants */
 
-#define M_MODE_INTERRUPTS (MIP_MSIP | MIP_MTIP | MIP_MEIP)
-#define S_MODE_INTERRUPTS (MIP_SSIP | MIP_STIP | MIP_SEIP)
+#define M_MODE_INTERRUPTS  (MIP_MSIP | MIP_MTIP | MIP_MEIP)
+#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;
@@ -257,6 +272,7 @@ static const target_ulong sstatus_v1_10_mask = SSTATUS_SIE | SSTATUS_SPIE |
     SSTATUS_UIE | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS |
     SSTATUS_SUM | SSTATUS_MXR | SSTATUS_SD;
 static const target_ulong sip_writable_mask = SIP_SSIP | MIP_USIP | MIP_UEIP;
+static const target_ulong hip_writable_mask = MIP_VSSIP | MIP_VSTIP | MIP_VSEIP;
 
 #if defined(TARGET_RISCV32)
 static const char valid_vm_1_09[16] = {
@@ -756,6 +772,112 @@ static int write_satp(CPURISCVState *env, int csrno, target_ulong val)
     return 0;
 }
 
+/* Hypervisor Extensions */
+static int read_hstatus(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->hstatus;
+    return 0;
+}
+
+static int write_hstatus(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->hstatus = val;
+    return 0;
+}
+
+static int read_hedeleg(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->hedeleg;
+    return 0;
+}
+
+static int write_hedeleg(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->hedeleg = val;
+    return 0;
+}
+
+static int read_hideleg(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->hideleg;
+    return 0;
+}
+
+static int write_hideleg(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->hideleg = val;
+    return 0;
+}
+
+static int rmw_hip(CPURISCVState *env, int csrno, target_ulong *ret_value,
+                   target_ulong new_value, target_ulong write_mask)
+{
+    int ret = rmw_mip(env, 0, ret_value, new_value,
+                      write_mask & hip_writable_mask);
+
+    return ret;
+}
+
+static int read_hie(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->mie & VS_MODE_INTERRUPTS;
+    return 0;
+}
+
+static int write_hie(CPURISCVState *env, int csrno, target_ulong val)
+{
+    target_ulong newval = (env->mie & ~VS_MODE_INTERRUPTS) | (val & VS_MODE_INTERRUPTS);
+    return write_mie(env, CSR_MIE, newval);
+}
+
+static int read_hcounteren(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->hcounteren;
+    return 0;
+}
+
+static int write_hcounteren(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->hcounteren = val;
+    return 0;
+}
+
+static int read_htval(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->htval;
+    return 0;
+}
+
+static int write_htval(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->htval = val;
+    return 0;
+}
+
+static int read_htinst(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->htinst;
+    return 0;
+}
+
+static int write_htinst(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->htinst = val;
+    return 0;
+}
+
+static int read_hgatp(CPURISCVState *env, int csrno, target_ulong *val)
+{
+    *val = env->hgatp;
+    return 0;
+}
+
+static int write_hgatp(CPURISCVState *env, int csrno, target_ulong val)
+{
+    env->hgatp = val;
+    return 0;
+}
+
 /* Physical Memory Protection */
 static int read_pmpcfg(CPURISCVState *env, int csrno, target_ulong *val)
 {
@@ -959,6 +1081,16 @@ static riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
     /* Supervisor Protection and Translation */
     [CSR_SATP] =                { smode, read_satp,        write_satp        },
 
+    [CSR_HSTATUS] =             { hmode,   read_hstatus,     write_hstatus    },
+    [CSR_HEDELEG] =             { hmode,   read_hedeleg,     write_hedeleg    },
+    [CSR_HIDELEG] =             { hmode,   read_hideleg,     write_hideleg    },
+    [CSR_HIP] =                 { hmode,   NULL,     NULL,     rmw_hip        },
+    [CSR_HIE] =                 { hmode,   read_hie,         write_hie        },
+    [CSR_HCOUNTEREN] =          { hmode,   read_hcounteren,  write_hcounteren },
+    [CSR_HTVAL] =               { hmode,   read_htval,       write_htval      },
+    [CSR_HTINST] =              { hmode,   read_htinst,      write_htinst     },
+    [CSR_HGATP] =               { hmode,   read_hgatp,       write_hgatp      },
+
     /* Physical Memory Protection */
     [CSR_PMPCFG0  ... CSR_PMPADDR9] =  { pmp,   read_pmpcfg,  write_pmpcfg   },
     [CSR_PMPADDR0 ... CSR_PMPADDR15] = { pmp,   read_pmpaddr, write_pmpaddr  },