[PATCH v6 53/60] i386/cpu: introduce mark_forced_on_features()

[Xiaoyao Li <xiaoyao.li@xxxxxxxxx>]

Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
 target/i386/cpu.c | 29 +++++++++++++++++++++++++++++
 target/i386/cpu.h |  5 +++++
 2 files changed, 34 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index e728fb6b9f10..472ab206d8fe 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -5507,6 +5507,35 @@ void mark_unavailable_features(X86CPU *cpu, FeatureWord w, uint64_t mask,
     }
 }
 
+void mark_forced_on_features(X86CPU *cpu, FeatureWord w, uint64_t mask,
+                             const char *verbose_prefix)
+{
+    CPUX86State *env = &cpu->env;
+    FeatureWordInfo *f = &feature_word_info[w];
+    int i;
+
+    if (!cpu->force_features) {
+        env->features[w] |= mask;
+    }
+
+    cpu->forced_on_features[w] |= mask;
+
+    if (!verbose_prefix) {
+        return;
+    }
+
+    for (i = 0; i < 64; ++i) {
+        if ((1ULL << i) & mask) {
+            g_autofree char *feat_word_str = feature_word_description(f, i);
+            warn_report("%s: %s%s%s [bit %d]",
+                        verbose_prefix,
+                        feat_word_str,
+                        f->feat_names[i] ? "." : "",
+                        f->feat_names[i] ? f->feat_names[i] : "", i);
+        }
+    }
+}
+
 static void x86_cpuid_version_get_family(Object *obj, Visitor *v,
                                          const char *name, void *opaque,
                                          Error **errp)
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index e70e7f5ced4b..b5b1c3917427 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -2135,6 +2135,9 @@ struct ArchCPU {
     /* Features that were filtered out because of missing host capabilities */
     FeatureWordArray filtered_features;
 
+    /* Features that are forced enabled by underlying hypervisor, e.g., TDX */
+    FeatureWordArray forced_on_features;
+
     /* Enable PMU CPUID bits. This can't be enabled by default yet because
      * it doesn't have ABI stability guarantees, as it passes all PMU CPUID
      * bits returned by GET_SUPPORTED_CPUID (that depend on host CPU and kernel
@@ -2446,6 +2449,8 @@ void host_cpuid(uint32_t function, uint32_t count,
 bool cpu_has_x2apic_feature(CPUX86State *env);
 void mark_unavailable_features(X86CPU *cpu, FeatureWord w, uint64_t mask,
                                const char *verbose_prefix);
+void mark_forced_on_features(X86CPU *cpu, FeatureWord w, uint64_t mask,
+                             const char *verbose_prefix);
 
 static inline bool x86_has_cpuid_0x1f(X86CPU *cpu)
 {
-- 
2.34.1