Renesas SH7781 - Manual (Page 201)

7. Memory Management Unit (MMU)
Rev.1.00 Jan. 10, 2008 Page 171 of 1658
REJ09B0261-0100
0001: 4-Kbyte page
0010: 8-Kbyte page
0100: 64-Kbyte page
0101: 256-Kbyte page
0111: 1-Mbyte page
1000: 4-Mbyte page
1100: 64-Mbyte page
Note: When a value other than those listed above is recorded, operation is not guaranteed.
• V: Validity bit
Indicates whether the entry is valid.
0: Invalid
1: Valid
Cleared to 0 by a power-on reset.
Not affected by a manual reset.
• PPN: Physical page number
Upper 19 bits of the physical address.
With a 1-Kbyte page, PPN[28:10] are valid.
With a 4-Kbyte page, PPN[28:12] are valid.
With a 8-Kbyte page, PPN[28:13] are valid.
With a 64-Kbyte page, PPN[28:16] are valid.
With a 256-Kbyte page, PPN[28:18] are valid.
With a 1-Mbyte page, PPN[28:20] are valid.
With a 4-Mbyte page, PPN[28:22] are valid.
With a 64-Mbyte page, PPN[28:26] are valid.
The synonym problem must be taken into account when setting the PPN (see section 7.5.5,
Avoiding Synonym Problems).
• EPR: Protection key data
6-bit data expressing the page access right as a code.
Reading, writing, and execution (instruction fetch) in privileged mode and reading, writing,
and execution (instruction fetch) in user mode can be set independently. Each bit is disabled by
0 and enabled by 1.
EPR[5]: Reading in privileged mode
EPR[4]: Writing in privileged mode
EPR[3]: Execution in privileged mode (instruction fetch)
EPR[2]: Reading in user mode