S3C2500B
PROGRAMMER
′′
S MODEL
2-25
2.16.1.5 Register 3: Write buffer control register
This register contains a write buffer control (bufferable) attribute bit for each of the eight areas of memory. Each
bit is used in conjunction with the cacheable bit to control write-buffer operation. For a description of buffer
behavior, see The write buffer on page 4-11.
Setting a bit makes an area bufferable, clearing a bit makes an area unbuffered. For example:
MCR p15,0,Rd,c3,c0,0; Write data-bufferable bits
MRC p15,0,Rd,c3,c0,0; Read data-bufferable bits
NOTE
The opcode_2 field should be 0 because the write buffer only operates on data regions. The following
table, therefore, only applies to the DCache.
All defined bits in the control register are set to zero at reset.
Table 2-11. Write Buffer Control Register
Register Bits
Functions
7
Write buffer control bit (B_d7) for data area 7
6
Write buffer control bit (B_d6) for data area 6
5
Write buffer control bit (B_d5) for data area 5
4
Write buffer control bit (B_d4) for data area 4
3
Write buffer control bit (B_d3) for data area 3
2
Write buffer control bit (B_d2) for data area 2
1
Write buffer control bit (B_d1) for data area 1
0
Write buffer control bit (B_d0) for data area 0
2.16.1.6 Register 5: Instruction and data space protection registers
These registers contain the access permission bits for the instruction and data protection regions. The opcode_2
field determines whether the instruction or data access permissions are programmed.
If the opcode_2 field = 0, the data space bits are programmed. For example:
MCR p15,0,Rd,c5,c0,0; Write data space access permissions
MCR p15,0,Rd,c5,c0,0; Read data space access permissions
If the opcode_2 field =1, the instruction space bits are programmed. For example:
MCR p15,0,Rd,c5,c0,1; Write instruction space access permissions
MRC p15,0,Rd,c5,c0,1; Read instruction space access permissions
Summary of Contents for S3C2500B
Page 2: ...S3C2500B 32 BIT RISC MICROPROCESSOR USER S MANUAL Revision 1 ...
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Page 80: ...PRODUCT OVERVIEW S3C2500B 1 46 NOTES ...
Page 296: ...MEMORY CONTROLLER S3C2500B 5 60 NOTES ...
Page 531: ...GDMA CONTROLLER S3C2500B 12 24 NOTES ...
Page 593: ...I O PORTS S3C2500B 15 12 NOTES ...