SH7713 datasheet(243/904 Pages) RENESAS

243 / 904 page

Section 5 Memory Management Unit (MMU)

Rev.1.50 Aug. 30, 2006 Page 203 of 860

REJ09B0288-0150

Virtual address 1 H'00000000

→ physical address H'00000C00

Virtual address 2 H'00000C00

→ physical address H'00000C00

Virtual address 1 is recorded in cache entry H'000, and virtual address 2 in cache entry H'0C0.

Since two virtual addresses are recorded in different cache entries despite the fact that the physical

addresses are the same, memory inconsistency will occur as soon as a write is performed to either

virtual address.

Consequently, the following restrictions apply to the recording of address translation information

in TLB entries.

1. When address translation information whereby a number of 1-kbyte page TLB entries are

translated into the same physical address is recorded in the TLB, ensure that the VPN [n:10]

are the same.

2. When address translation information whereby a number of 4-kbyte page TLB entries are

translated into the same physical address is recorded in the TLB, ensure that the VPN [n:12] is

the same.

3. Do not use the same physical addresses for address translation information of different page

sizes.

The above restrictions apply only when performing accesses using the cache.

Note:

When multiple items of address translation information use the same physical memory to

provide for future SuperH RISC engine family expansion, ensure that the VPN bits 20 to

10 are the same.

SH7713 Datasheet(PDF) 243 Page - Renesas Technology Corp