ssstateen is defined in RVA22 as:

"Supervisor-mode view of the state-enable extension. The supervisor-mode
(sstateen0-3) and hypervisor-mode (hstateen0-3) state-enable registers
must be provided."

Add ssstateen as a named feature that is available if we also have
smstateen.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/cpu.c         | 2 ++
 target/riscv/cpu_cfg.h     | 1 +
 target/riscv/tcg/tcg-cpu.c | 9 ++++++++-
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index f219f0c3b5..4ad91722a0 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -191,6 +191,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(ssccptr, PRIV_VERSION_1_11_0, has_priv_1_11),
     ISA_EXT_DATA_ENTRY(sscofpmf, PRIV_VERSION_1_12_0, ext_sscofpmf),
     ISA_EXT_DATA_ENTRY(sscounterenw, PRIV_VERSION_1_12_0, has_priv_1_12),
+    ISA_EXT_DATA_ENTRY(ssstateen, PRIV_VERSION_1_12_0, ext_ssstateen),
     ISA_EXT_DATA_ENTRY(sstc, PRIV_VERSION_1_12_0, ext_sstc),
     ISA_EXT_DATA_ENTRY(sstvala, PRIV_VERSION_1_12_0, has_priv_1_12),
     ISA_EXT_DATA_ENTRY(sstvecd, PRIV_VERSION_1_12_0, has_priv_1_12),
@@ -1607,6 +1608,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_experimental_exts[] = {
  */
 const RISCVCPUMultiExtConfig riscv_cpu_named_features[] = {
     MULTI_EXT_CFG_BOOL("zic64b", ext_zic64b, true),
+    MULTI_EXT_CFG_BOOL("ssstateen", ext_ssstateen, true),
 
     DEFINE_PROP_END_OF_LIST(),
 };
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 59d6fc445d..c7bf455614 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -139,6 +139,7 @@ struct RISCVCPUConfig {
     /* Named features  */
     bool ext_svade;
     bool ext_zic64b;
+    bool ext_ssstateen;
 
     /*
      * Always 'true' booleans for named features
diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index cd83968166..0b9be2b0d3 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -204,10 +204,15 @@ static void riscv_cpu_enable_named_feat(RISCVCPU *cpu, uint32_t feat_offset)
       * All other named features are already enabled
       * in riscv_tcg_cpu_instance_init().
       */
-    if (feat_offset == CPU_CFG_OFFSET(ext_zic64b)) {
+    switch (feat_offset) {
+    case CPU_CFG_OFFSET(ext_zic64b):
         cpu->cfg.cbom_blocksize = 64;
         cpu->cfg.cbop_blocksize = 64;
         cpu->cfg.cboz_blocksize = 64;
+        break;
+    case CPU_CFG_OFFSET(ext_ssstateen):
+        cpu->cfg.ext_smstateen = true;
+        break;
     }
 }
 
@@ -343,6 +348,8 @@ static void riscv_cpu_update_named_features(RISCVCPU *cpu)
     cpu->cfg.ext_zic64b = cpu->cfg.cbom_blocksize == 64 &&
                           cpu->cfg.cbop_blocksize == 64 &&
                           cpu->cfg.cboz_blocksize == 64;
+
+    cpu->cfg.ext_ssstateen = cpu->cfg.ext_smstateen;
 }
 
 static void riscv_cpu_validate_g(RISCVCPU *cpu)
-- 
2.47.0