text: #ifndef PHYS_H_
  #define PHYS_H_
  
  #include <stdint.h>
  
  #define REAL_MODE_BOUNDARY  (0x00100000)
  
  /* where the entry count and entry pointers will be stored by the BIOS e820 function */
  #define ENTRY_COUNT_ADDR    (0x4000)
  #define ENTRIES_PTR         (ENTRY_COUNT_ADDR+4)
  
  
  #define PAGING_BIT          (31)
  
  
  
  typedef enum mem_type_e {
      MEM_TYPE_INVALID = 0,
      MEM_TYPE_FREE = 1,
      MEM_TYPE_RESERVED = 2,
      MEM_TYPE_ACPI_RECLAIMABLE = 3,
      MEM_TYPE_ACPI_NON_VOLATILE = 4,
      MEM_TYPE_BAD = 5,
      MEM_TYPE_MAX_NO
  } mem_type_e;
  
  
  typedef struct mem_entry_s {
      uint32_t base_lo;
      uint32_t base_hi;
      uint32_t length_lo;
      uint32_t length_hi;
      uint32_t type;
      uint32_t acpi_attr;
  } mem_entry_t;
  
  
  uint32_t get_available_mem(void);
  
  
  #endif /* PHYS_H_ */