ARM R4F Computer Hardware User Manual


 
Level One Memory System
ARM DDI 0363E Copyright © 2009 ARM Limited. All rights reserved. 8-28
ID013010 Non-Confidential, Unrestricted Access
Write a line to the eviction buffer in one cycle, a 256-bit read access.
Fill a line in one cycle from the linefill buffer, a 256-bit write access.
Figure 8-3 shows a cache look-up being performed on all banks with one RAM access.
Figure 8-3 Nonsequential read operation performed with one RAM access.
Figure 8-4 shows the appropriate bank RAM being selected for a sequential read operation.
Figure 8-4 Sequential read operation performed with one RAM access
The data RAM organization is optimized for 64-bit read operations, because with the same
address, two words on the same way can be selected.
Data RAM sizes depend on the build option selected, and are described in:
Data RAM sizes without parity or ECC implemented on page 8-29
Data RAM sizes with parity implemented on page 8-29
Data RAM sizes with ECC implemented on page 8-30.
RAM address
0
1
2
3
Way 1
Word 6
Bank 0
Way 1
Word 7
Way 2
Word 4
Way 2
Word 5
Way 3
Word 2
Way 3
Word 3
Way 0
Word 0
Way 0
Word 1
Bank 1
Way 2
Word 6
Bank 2
Way 2
Word 7
Way 3
Word 4
Way 3
Word 5
Way 0
Word 2
Way 0
Word 3
Way 1
Word 0
Way 1
Word 1
Bank 3
Way 3
Word 6
Bank 4
Way 3
Word 7
Way 0
Word 4
Way 0
Word 5
Way 1
Word 2
Way 1
Word 3
Way 2
Word 0
Way 2
Word 1
Bank 5
Way 0
Word 7
Way 1
Word 4
Way 1
Word 5
Way 2
Word 2
Way 2
Word 3
Way 3
Word 0
Way 3
Word 1
Bank 7
Bank 6
Way 0
Word 6
256-bit wide
RAM address
0
1
2
3
Way 1
Word 6
Bank 0
Way 1
Word 7
Way 2
Word 4
Way 2
Word 5
Way 3
Word 2
Way 3
Word 3
Way 0
Word 0
Way 0
Word 1
Bank 1
Way 2
Word 6
Bank 2
Way 2
Word 7
Way 3
Word 4
Way 3
Word 5
Way 0
Word 2
Way 0
Word 3
Way 1
Word 0
Way 1
Word 1
Bank 3
Way 3
Word 6
Bank 4
Way 3
Word 7
Way 0
Word 4
Way 0
Word 5
Way 1
Word 2
Way 1
Word 3
Way 2
Word 0
Way 2
Word 1
Bank 5
Way 0
Word 7
Way 1
Word 4
Way 1
Word 5
Way 2
Word 2
Way 2
Word 3
Way 3
Word 0
Way 3
Word 1
Bank 7
Bank 6
Way 0
Word 6