From: Frank Chang <frank.chang@sifive.com>

Zc extension has special implied rules that need to be handled separately.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
---
 target/riscv/tcg/tcg-cpu.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index 899d605d36..ed10ac799a 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -897,11 +897,45 @@ static void cpu_enable_implied_rule(RISCVCPU *cpu,
     }
 }
 
+/* Zc extension has special implied rules that need to be handled separately. */
+static void cpu_enable_zc_implied_rules(RISCVCPU *cpu)
+{
+    RISCVCPUClass *mcc = RISCV_CPU_GET_CLASS(cpu);
+    CPURISCVState *env = &cpu->env;
+
+    if (cpu->cfg.ext_zce) {
+        cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zca), true);
+        cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcb), true);
+        cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcmp), true);
+        cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcmt), true);
+
+        if (riscv_has_ext(env, RVF) && mcc->misa_mxl_max == MXL_RV32) {
+            cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcf), true);
+        }
+    }
+
+    /* Zca, Zcd and Zcf has a PRIV 1.12.0 restriction */
+    if (riscv_has_ext(env, RVC) && env->priv_ver >= PRIV_VERSION_1_12_0) {
+        cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zca), true);
+
+        if (riscv_has_ext(env, RVF) && mcc->misa_mxl_max == MXL_RV32) {
+            cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcf), true);
+        }
+
+        if (riscv_has_ext(env, RVD)) {
+            cpu_cfg_ext_auto_update(cpu, CPU_CFG_OFFSET(ext_zcd), true);
+        }
+    }
+}
+
 static void riscv_cpu_enable_implied_rules(RISCVCPU *cpu)
 {
     RISCVCPUImpliedExtsRule *rule;
     int i;
 
+    /* Enable the implied extensions for Zc. */
+    cpu_enable_zc_implied_rules(cpu);
+
     /* Enable the implied MISAs. */
     for (i = 0; (rule = riscv_misa_implied_rules[i]); i++) {
         if (riscv_has_ext(&cpu->env, rule->ext)) {
-- 
2.43.2