target/riscv: remove RISCV_FEATURE_DEBUG

RISCV_FEATURE_DEBUG will always follow the value defined by
cpu->cfg.debug flag. Read the flag instead.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-5-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

target/riscv/cpu.c

@@ -637,7 +637,7 @@ static void riscv_cpu_reset_hold(Object *obj)
     set_default_nan_mode(1, &env->fp_status);
 
 #ifndef CONFIG_USER_ONLY
-    if (riscv_feature(env, RISCV_FEATURE_DEBUG)) {
+    if (cpu->cfg.debug) {
         riscv_trigger_init(env);
     }
 
@@ -935,10 +935,6 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    if (cpu->cfg.debug) {
-        riscv_set_feature(env, RISCV_FEATURE_DEBUG);
-    }
-
 
 #ifndef CONFIG_USER_ONLY
     if (cpu->cfg.ext_sstc) {

target/riscv/cpu.h

@@ -89,7 +89,6 @@ enum {
     RISCV_FEATURE_MMU,
     RISCV_FEATURE_PMP,
     RISCV_FEATURE_EPMP,
-    RISCV_FEATURE_DEBUG
 };
 
 /* Privileged specification version */

target/riscv/cpu_helper.c

@@ -105,7 +105,7 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS,
                            get_field(env->mstatus_hs, MSTATUS_VS));
     }
-    if (riscv_feature(env, RISCV_FEATURE_DEBUG) && !icount_enabled()) {
+    if (cpu->cfg.debug && !icount_enabled()) {
         flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled);
     }
 #endif

target/riscv/csr.c

@@ -437,7 +437,7 @@ static RISCVException epmp(CPURISCVState *env, int csrno)
 
 static RISCVException debug(CPURISCVState *env, int csrno)
 {
-    if (riscv_feature(env, RISCV_FEATURE_DEBUG)) {
+    if (riscv_cpu_cfg(env)->debug) {
         return RISCV_EXCP_NONE;
     }
 

target/riscv/machine.c

@@ -226,9 +226,8 @@ static const VMStateDescription vmstate_kvmtimer = {
 static bool debug_needed(void *opaque)
 {
     RISCVCPU *cpu = opaque;
-    CPURISCVState *env = &cpu->env;
 
-    return riscv_feature(env, RISCV_FEATURE_DEBUG);
+    return cpu->cfg.debug;
 }
 
 static int debug_post_load(void *opaque, int version_id)