HD6417706 RENESAS [Renesas Technology Corp], HD6417706 Datasheet - Page 106

• Manufacturer Part Number: HD6417706
• Description: Renesas 32-Bit RISC Microcomputer Super RISC engine Family/SH7700 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Rev. 4.00, 03/04, page 60 of 660
Legend
VPN (31–17) VPN (11–10)
ASID: Address space identifier. Indicates the process that can access a virtual page. In single
VPN: Virtual page number. Top 22 bits of virtual address for a 1-kbyte page, or top 20 bits of
PPN: Physical page number. Top 22 bits of physical address. PPN bits 11-10 are not used in
SH: Share status bit
PR: Set the most significant bit to 0.
SZ: Page-size bit
C: Cacheable bit. Indicates whether the page is cacheable.
D: Dirty bit. Indicates whether the page has been written to.
(15)
V: Valid bit. Indicates whether entry is valid.
virtual address for a 4-kbyte page. Since VPN bits 16-12 are used as the index number,
they are not stored in the TLB entry.
virtual memory mode and user mode, or in multiple virtual memory mode, if the SH bit is
0, the address is compared with the ASID in PTEH when address comparison is
performed.
0 = Page not shared between processes
1 = Page shared between processes
0 = 1-kbyte page
1 = 4-kbyte page
0 = Invalid
1 = Valid
Cleared to 0 by a power-on reset. Not affected by a manual reset.
case of a 4-kbyte page. Attention must be paid to the synonym problem in case of a 1-
kbyte page (see section 3.4.4 Avoiding Synonym Problems).
Protection key field. 2-bit field encoded to define the access rights to the page.
00: Reading only is possible in privileged mode.
01: Reading/writing is possible in privileged mode.
10: Reading only is possible in privileged/user mode.
11: Reading/writing is possible in privileged/user mode.
0: Non-cacheable
1: Cacheable
0 = Not written to
1 = Written to
31
31
Figure 3.4 Virtual Address and TLB Structure
(2)
ASID
VPN
Virtual address (1-kbyte page)
Virtual address (4-kbyte page)
(8)
VPN
(1)
V
TLB entry
12
10
11
PPN
(22)
9
Offset
Offset
PR
(2)
0
0
SZ
(1)
(1) (1)
C
D
SH
(1)