kern: implement init through InterruptTaskManager.Initialize()

libraries/libmesosphere/include/mesosphere/arch/arm64/kern_cpu.hpp

@@ -59,6 +59,12 @@ namespace ams::kern::arm64::cpu {
         EnsureInstructionConsistency();
     }
 
+    ALWAYS_INLINE void SwitchProcess(u64 ttbr, u32 proc_id) {
+        SetTtbr0El1(ttbr);
+        ContextIdRegisterAccessor(0).SetProcId(proc_id).Store();
+        InstructionMemoryBarrier();
+    }
+
     /* Helper for address access. */
     ALWAYS_INLINE bool GetPhysicalAddressWritable(KPhysicalAddress *out, KVirtualAddress addr, bool privileged = false) {
         const uintptr_t va = GetInteger(addr);

libraries/libmesosphere/include/mesosphere/arch/arm64/kern_k_page_table.hpp

@@ -34,6 +34,11 @@ namespace ams::kern::arm64 {
 
             static NOINLINE void Initialize(s32 core_id);
 
+            ALWAYS_INLINE void Activate(u32 proc_id) {
+                cpu::DataSynchronizationBarrier();
+                cpu::SwitchProcess(this->ttbr, proc_id);
+            }
+
             NOINLINE Result InitializeForKernel(void *table, KVirtualAddress start, KVirtualAddress end);
             Result Finalize();
     };

libraries/libmesosphere/include/mesosphere/arch/arm64/kern_k_supervisor_page_table.hpp

@@ -28,6 +28,7 @@ namespace ams::kern::arm64 {
             constexpr KSupervisorPageTable() : page_table(), ttbr0() { /* ... */ }
 
             NOINLINE void Initialize(s32 core_id);
+            NOINLINE void Activate();
             void Finalize(s32 core_id);
     };