SH7710 Datasheet, PDF (264/996 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 6 Cache
6.3 Operation
6.3.1 Searching the Cache
If the cache is enabled (the CE bit in CCR1 = 1), whenever instructions or data in spaces P0, P1,
P3, and U0 are accessed the cache will be searched to see if the desired instruction or data is in the
cache. Figure 6.2 illustrates the method by which the cache is searched. The cache is a physical
cache and holds physical addresses in its address section.
Entries are selected using bits 12 to 4 of the address (virtual) of the access to memory and the tag
address of that entry is read. The virtual address (bits 31 to 10) of the access to memory and the
physical address (tag address) read from the address array are compared. The address comparison
uses all four ways. When the comparison shows a match and the selected entry is valid (V = 1), a
cache hit occurs. When the comparison does not show a match or the selected entry is not valid (V
= 0), a cache miss occurs. Figure 6.2 shows a hit on way 1.
Rev. 2.00 Dec. 07, 2005 Page 222 of 950
REJ09B0079-0200