1 files changed, 118 insertions, 0 deletions
diff --git a/fesvr/device.h b/fesvr/device.h
new file mode 100644
index 0000000..1387b74
--- /dev/null
+++ b/fesvr/device.h
@@ -0,0 +1,118 @@
+#ifndef _DEVICE_H
+#define _DEVICE_H
+
+#include <vector>
+#include <queue>
+#include <cstring>
+#include <string>
+#include <functional>
+
+class memif_t;
+
+class command_t
+{
+ public:
+  typedef std::function<void(uint64_t)> callback_t;
+  command_t(memif_t& memif, uint64_t tohost, callback_t cb)
+    : _memif(memif), tohost(tohost), cb(cb) {}
+
+  memif_t& memif() { return _memif; }
+  uint8_t device() { return tohost >> 56; }
+  uint8_t cmd() { return tohost >> 48; }
+  uint64_t payload() { return tohost << 16 >> 16; }
+  void respond(uint64_t resp) { cb((tohost >> 48 << 48) | (resp << 16 >> 16)); }
+
+  static const size_t MAX_COMMANDS = 256;
+  static const size_t MAX_DEVICES = 256;
+
+ private:
+  memif_t& _memif;
+  uint64_t tohost;
+  callback_t cb;
+};
+
+class device_t
+{
+ public:
+  device_t();
+  virtual ~device_t() {}
+  virtual const char* identity() = 0;
+  virtual void tick() {}
+
+  void handle_command(command_t cmd);
+
+ protected:
+  typedef std::function<void(command_t)> command_func_t;
+  void register_command(size_t, command_func_t, const char*);
+
+ private:
+  device_t& operator = (const device_t&); // disallow
+  device_t(const device_t&); // disallow
+
+  static const size_t IDENTITY_SIZE = 64;
+  void handle_null_command(command_t cmd);
+  void handle_identify(command_t cmd);
+
+  std::vector<command_func_t> command_handlers;
+  std::vector<std::string> command_names;
+};
+
+class bcd_t : public device_t
+{
+ public:
+  bcd_t();
+  const char* identity() { return "bcd"; }
+  void tick();
+
+ private:
+  void handle_read(command_t cmd);
+  void handle_write(command_t cmd);
+
+  std::queue<command_t> pending_reads;
+};
+
+class disk_t : public device_t
+{
+ public:
+  disk_t(const char* fn);
+  ~disk_t();
+  const char* identity() { return id.c_str(); }
+
+ private:
+  struct request_t
+  {
+    uint64_t addr;
+    uint64_t offset;
+    uint64_t size;
+    uint64_t tag;
+  };
+
+  void handle_read(command_t cmd);
+  void handle_write(command_t cmd);
+
+  std::string id;
+  size_t size;
+  int fd;
+};
+
+class null_device_t : public device_t
+{
+ public:
+  const char* identity() { return ""; }
+};
+
+class device_list_t
+{
+ public:
+  device_list_t();
+  void register_device(device_t* dev);
+  void handle_command(command_t cmd);
+  void tick();
+
+ private:
+  std::vector<device_t*> devices;
+  null_device_t null_device;
+  size_t num_devices;
+};
+
+#endif