target/riscv: debug: Restrict the range of tselect value can be written

The value of tselect CSR can be written should be limited within the
range of supported triggers number.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <20220909134215.1843865-5-bmeng.cn@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/target/riscv/debug.c b/target/riscv/debug.c
index 06feef7d6734888afdb78777082c407363ae937e..d6666164cd8f59d5d16420ecd96c89da10f3700d 100644 (file)
--- a/target/riscv/debug.c
+++ b/target/riscv/debug.c
@@ -127,10 +127,6 @@ bool tdata_available(CPURISCVState *env, int tdata_index)
         return false;
     }
 
-    if (unlikely(env->trigger_cur >= RV_MAX_TRIGGERS)) {
-        return false;
-    }
-
     return tdata_mapping[trigger_type][tdata_index];
 }
 
@@ -141,8 +137,9 @@ target_ulong tselect_csr_read(CPURISCVState *env)
 
 void tselect_csr_write(CPURISCVState *env, target_ulong val)
 {
-    /* all target_ulong bits of tselect are implemented */
-    env->trigger_cur = val;
+    if (val < RV_MAX_TRIGGERS) {
+        env->trigger_cur = val;
+    }
 }
 
 static target_ulong tdata1_validate(CPURISCVState *env, target_ulong val,