Svukte extension add HUKTE bit, bit[24] in hstatus CSR. The written
value will be masked when the svukte extension is not enabled.

When hstatus[HUKTE] bit is set, HLV/HLVX/HSV work in the U-mode should
do svukte check.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---
 target/riscv/cpu_bits.h | 1 +
 target/riscv/csr.c      | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index 4b9f899217..fe4e34c64a 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -604,6 +604,7 @@ typedef enum {
 #define HSTATUS_VTVM         0x00100000
 #define HSTATUS_VTW          0x00200000
 #define HSTATUS_VTSR         0x00400000
+#define HSTATUS_HUKTE        0x01000000
 #define HSTATUS_VSXL         0x300000000
 
 #define HSTATUS32_WPRI       0xFF8FF87E
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 1936a6f32a..b6fa8ae53f 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -3540,6 +3540,9 @@ static RISCVException read_hstatus(CPURISCVState *env, int csrno,
 static RISCVException write_hstatus(CPURISCVState *env, int csrno,
                                     target_ulong val)
 {
+    if (!env_archcpu(env)->cfg.ext_svukte) {
+        val = val & (~HSTATUS_HUKTE);
+    }
     env->hstatus = val;
     if (riscv_cpu_mxl(env) != MXL_RV32 && get_field(val, HSTATUS_VSXL) != 2) {
         qemu_log_mask(LOG_UNIMP,
-- 
2.34.1