device_t: device_factories should be const

riscv/abstract_device.h

@@ -21,16 +21,16 @@ class abstract_device_t {
 // parameterized by parsing the DTS
 class device_factory_t {
 public:
-  virtual abstract_device_t* parse_from_fdt(const void* fdt, const sim_t* sim, reg_t* base) = 0;
-  virtual std::string generate_dts(const sim_t* sim) = 0;
+  virtual abstract_device_t* parse_from_fdt(const void* fdt, const sim_t* sim, reg_t* base) const = 0;
+  virtual std::string generate_dts(const sim_t* sim) const = 0;
   virtual ~device_factory_t() {}
 };
 
 #define REGISTER_DEVICE(name, parse, generate) \
   class name##_factory_t : public device_factory_t { \
   public: \
-  name##_t* parse_from_fdt(const void* fdt, const sim_t* sim, reg_t* base) override { return parse(fdt, sim, base); } \
-  std::string generate_dts(const sim_t* sim) override { return generate(sim); } \
-  }; device_factory_t *name##_factory = new name##_factory_t();
+  name##_t* parse_from_fdt(const void* fdt, const sim_t* sim, reg_t* base) const override { return parse(fdt, sim, base); } \
+  std::string generate_dts(const sim_t* sim) const override { return generate(sim); } \
+  }; const device_factory_t *name##_factory = new name##_factory_t();
 
 #endif

riscv/sim.cc

@@ -120,7 +120,7 @@ sim_t::sim_t(const cfg_t *cfg, bool halted,
   // that's not bus-accessible), but it should handle the normal use cases. In
   // particular, the default device tree configuration that you get without
   // setting the dtb_file argument has one.
-  std::vector<device_factory_t*> device_factories = {
+  std::vector<const device_factory_t*> device_factories = {
     clint_factory, // clint must be element 0
     plic_factory, // plic must be element 1
     ns16550_factory};
@@ -138,7 +138,7 @@ sim_t::sim_t(const cfg_t *cfg, bool halted,
   } else {
     std::pair<reg_t, reg_t> initrd_bounds = cfg->initrd_bounds();
     std::string device_nodes;
-    for (device_factory_t *factory : device_factories)
+    for (const device_factory_t *factory : device_factories)
       device_nodes.append(factory->generate_dts(this));
     dts = make_dts(INSNS_PER_RTC_TICK, CPU_HZ,
                    initrd_bounds.first, initrd_bounds.second,
@@ -162,7 +162,7 @@ sim_t::sim_t(const cfg_t *cfg, bool halted,
   void *fdt = (void *)dtb.c_str();
 
   for (size_t i = 0; i < device_factories.size(); i++) {
-    device_factory_t *factory = device_factories[i];
+    const device_factory_t *factory = device_factories[i];
     reg_t device_base = 0;
     abstract_device_t* device = factory->parse_from_fdt(fdt, this, &device_base);
     if (device) {