target/riscv: add 'parent' in profile description

Certain S-mode profiles, like RVA22S64 and RVA23S64, mandate all the
mandatory extensions of their respective U-mode profiles. RVA22S64
includes all mandatory extensions of RVA22U64, and the same happens with
RVA23 profiles.

Add a 'parent' field to allow profiles to enable other profiles. This
will allow us to describe S-mode profiles by specifying their parent
U-mode profile, then adding just the S-mode specific extensions.

We're naming the field 'parent' to consider the possibility of other
uses (e.g. a s-mode profile including a previous s-mode profile) in the
future.

Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-25-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.c

@@ -1539,6 +1539,7 @@ Property riscv_cpu_options[] = {
  * having a cfg offset) at this moment.
  */
 static RISCVCPUProfile RVA22U64 = {
+    .parent = NULL,
     .name = "rva22u64",
     .misa_ext = RVI | RVM | RVA | RVF | RVD | RVC | RVU,
     .priv_spec = RISCV_PROFILE_ATTR_UNUSED,

target/riscv/cpu.h

@@ -77,6 +77,7 @@ const char *riscv_get_misa_ext_description(uint32_t bit);
 #define CPU_CFG_OFFSET(_prop) offsetof(struct RISCVCPUConfig, _prop)
 
 typedef struct riscv_cpu_profile {
+    struct riscv_cpu_profile *parent;
     const char *name;
     uint32_t misa_ext;
     bool enabled;

target/riscv/tcg/tcg-cpu.c

@@ -802,7 +802,7 @@ static void riscv_cpu_validate_profile(RISCVCPU *cpu,
     CPURISCVState *env = &cpu->env;
     const char *warn_msg = "Profile %s mandates disabled extension %s";
     bool send_warn = profile->user_set && profile->enabled;
-    bool profile_impl = true;
+    bool parent_enabled, profile_impl = true;
     int i;
 
 #ifndef CONFIG_USER_ONLY
@@ -855,6 +855,13 @@ static void riscv_cpu_validate_profile(RISCVCPU *cpu,
     }
 
     profile->enabled = profile_impl;
+
+    if (profile->parent != NULL) {
+        parent_enabled = object_property_get_bool(OBJECT(cpu),
+                                                  profile->parent->name,
+                                                  NULL);
+        profile->enabled = profile->enabled && parent_enabled;
+    }
 }
 
 static void riscv_cpu_validate_profiles(RISCVCPU *cpu)
@@ -1112,6 +1119,11 @@ static void cpu_set_profile(Object *obj, Visitor *v, const char *name,
     profile->user_set = true;
     profile->enabled = value;
 
+    if (profile->parent != NULL) {
+        object_property_set_bool(obj, profile->parent->name,
+                                 profile->enabled, NULL);
+    }
+
     if (profile->enabled) {
         cpu->env.priv_ver = profile->priv_spec;
     }