2 ic data array, 3 oc address array – Renesas SH7781 User Manual

Page 264

Advertising
background image

8. Caches

Rev.1.00 Jan. 10, 2008 Page 234 of 1658
REJ09B0261-0100

8.6.2

IC Data Array

The IC data array is allocated to addresses H'F100 0000 to H'F1FF FFFF in the P4 area. A data
array access requires a 32-bit address field specification (when reading or writing) and a 32-bit
data field specification. The way and entry to be accessed are specified in the address field, and
the longword data to be written is specified in the data field.

In the address field, bits [31:24] have the value H'F1 indicating the IC data array, and the way is
specified by bits [14:13] and the entry by bits [12:5]. Address field bits [4:2] are used for the
longword data specification in the entry. As only longword access is used, 0 should be specified
for address field bits [1:0].

The data field is used for the longword data specification.

The following two kinds of operation can be used on the IC data array:

1. IC data array read

Longword data is read into the data field from the data specified by the longword specification
bits in the address field in the IC entry corresponding to the way and entry set in the address
field.

2. IC data array write

The longword data specified in the data field is written for the data specified by the longword
specification bits in the address field in the IC entry corresponding to the way and entry set in
the address field.

Address field

31

23

12

5 4

2 1 0

1 1 1 1 0 0 0 1

Entry

L

Data field

31

0

Longword data

L

*

24

13

14

15

: Longword specification bits
: Don't care

Way

0 0

* * * * * * * * *

Figure 8.6 Memory-Mapped IC Data Array (Cache size = 32 Kbytes)

8.6.3

OC Address Array

The OC address array is allocated to addresses H'F400 0000 to H'F4FF FFFF in the P4 area. An
address array access requires a 32-bit address field specification (when reading or writing) and a

Advertising