To attain an information processor and a method for assigning memory address space by which size of the memory address space which can be assigned to a physical memory can be changed.
When a memory size priority mode for assigning a main memory 116 to the memory address space of a CPU 111 by giving the main memory priority over an I/O device is specified, a system BIOS executed by the CPU 111 assigns the main memory 116 to a standard memory address space 201 and at least a part of a memory/MMIO address space 202. On the other hand, when an extension device priority mode for assigning the I/O device to the memory address space of the CPU 111 by giving the I/O device priority over the main memory 116 is specified, the system BIOS assigns the main memory 116 to the standard memory address space 201 so that usable memory size is restricted to memory size of the standard memory address space 201.
Satoshi Kono
Makoto Nakamura
Kurata Masatoshi
Takashi Mine
Yoshihiro Fukuhara
Sadao Muramatsu
Ryo Hashimoto