ysyx-workbench/npc/csrc/devices/include/devices.hpp

#include <cstddef>
#include <cstdint>
#include <cstring>
#include <initializer_list>
#include <iostream>
#include <map>
#include <memory>
#include <spdlog/logger.h>
#include <spdlog/sinks/stdout_color_sinks.h>
#include <utility>

namespace Devices {
class Device {
public:
  uint8_t *p_buf;
  uint64_t addr;
  size_t len;
  Device(uint64_t addr, size_t len, uint8_t buf[])
      : addr(addr), len(len), p_buf(buf) {}
  virtual ~Device(){};
  virtual void io_handler(uint32_t offset, size_t len, bool is_write) = 0;
  void transfer(uint8_t *src, size_t len, bool is_write) {
    if (is_write) {
      memmove(p_buf, src, len);
    } else {
      memmove(src, p_buf, len);
    }
  };
};

class Serial : public Device {
  uint8_t buf[1];

public:
  Serial(uint64_t addr, size_t len);
  ~Serial() override{};
  void io_handler(uint32_t offset, size_t len, bool is_write) override;
  // void transfer(uint8_t *src, size_t len, bool is_write) override;
};

class RTC : public Device {
  uint8_t buf[8];
  uint64_t boot_time;
  uint64_t get_time_internal();
  uint64_t get_time();

public:
  RTC(uint64_t addr, size_t len);
  ~RTC() override{};
  void io_handler(uint32_t offset, size_t len, bool is_write) override;
  // void transfer(uint8_t *src, size_t len, bool is_write) override;
};

class DeviceMap {
  std::map<uint64_t, Device *> addr_to_device;
  std::shared_ptr<spdlog::logger> logger = spdlog::stdout_color_mt("devicemap");

public:
  DeviceMap(std::initializer_list<Device *> devices) {
    for (auto device : devices) {
      addr_to_device.insert(std::make_pair(device->addr, device));
    }
  }
  bool handle(uint64_t addr, uint8_t *data, size_t len, bool is_write) {
    auto it = addr_to_device.upper_bound(addr);
    if (it == addr_to_device.begin() ||
        (--it)->second->addr + it->second->len <= addr) {
      logger->error("Accessed an unintialized device at memory addr: 0x{:x}",
                    addr);
      return false;
    }
    auto &device = it->second;
    uint32_t offset = addr - device->addr;
    if (is_write) {
      device->transfer(data, len, is_write);
      device->io_handler(offset, len, is_write);
    } else {
      device->io_handler(offset, len, is_write);
      device->transfer(data, len, is_write);
    }
    return true;
  }
};
} // namespace Devices