
CHAPTER 5 MEMORY MANAGEMENT SYSTEM
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(3) kseg1 (32-bit Kernel mode, kernel space 1)
When KX = 0 in the Status register and the most-significant three bits of the virtual address space are 101, the
kseg1 virtual address space is selected; it is the current 512-Mbyte (2
References to kseg1 are not mapped through TLB; the physical address selected is defined by subtracting
0xA000 0000 from the virtual address.
Caches are disabled for accesses to these addresses, and main memory (or memory-mapped I/O device
registers) is accessed directly.
29
-byte) physical space.
(4) ksseg (32-bit Kernel mode, supervisor space)
When KX = 0 in the Status register and the most-significant three bits of the virtual address space are 110, the
ksseg virtual address space is selected; it is the current 512-Mbyte (2
address is extended with the contents of the 8-bit ASID field to form a unique virtual address.
References to ksseg are mapped through TLB. Whether cache can be used or not is determined by bit C of
each page’s TLB entry.
29
-byte) virtual address space. The virtual
(5) kseg3 (32-bit Kernel mode, kernel space 3)
When KX = 0 in the Status register and the most-significant three bits of the virtual address space are 111, the
kseg3 virtual address space is selected; it is the current 512-Mbyte (2
address is extended with the contents of the 8-bit ASID field to form a unique virtual address.
References to kseg3 are mapped through TLB. Whether cache can be used or not is determined by bit C of
each page’s TLB entry.
29
-byte) kernel virtual space. The virtual