UIO.h

#ifndef ZCU_UIO_H_INCLUDED
#define ZCU_UIO_H_INCLUDED
#include <stdint.h>
#include <unistd.h>
 
#include <string>
 
namespace pflib {
 
class UIO {
 public:
  UIO(const std::string& name, size_t size = 4096);
 
  ~UIO();
 
  uint32_t read(size_t i) { return (i < size_) ? (ptr_[i]) : (0xDEADB33F); }
 
  void write(size_t where, uint32_t what);
 
  uint32_t readMasked(size_t where, uint32_t mask) {
    return (read(where) & mask) >> first_bit_set(mask);
  }
 
  void writeMasked(size_t where, uint32_t mask, uint32_t val) {
    rmw(where, mask, (val << first_bit_set(mask)) & mask);
  }
 
  void rmw(size_t where, uint32_t bits_to_modify, uint32_t newval);
 
 private:
  void iopen(const std::string& dev, size_t size = 4096);
 
  int first_bit_set(uint32_t mask) {
    int i;
    for (i = 0; i < 32; i++)
      if ((mask & (1 << i)) != 0) return i;
    return 32;
  }
  std::string name_;
  size_t size_;
  uint32_t* ptr_;
  int handle_;
};
}  // namespace pflib
#endif