Coprocessors

5.2.10Register 9 – Read-Buffer Operations

The read buffer is controlled and accessed through register 9 of coprocessor 15. The functions supported are: flush-all buffers, flush-a-single entry, load-an-entry (1, 4 or 8 words), and enable/disable user mode access.

The CRm and OPC_2 fields are used to encode these control operations. All other values for OPC_2 and CRm are undefined and the results of using them are unpredictable.

Function

OPC_2

CRm

Data

 

 

 

 

Flush all entries

0b000

0b0000

Ignored

 

 

 

 

Flush Buffer 0

0b001

0b0000

Ignored

 

 

 

 

Flush Buffer 1

0b001

0b0001

Ignored

 

 

 

 

Flush Buffer 2

0b001

0b0010

Ignored

 

 

 

 

Flush Buffer 3

0b001

0b0011

Ignored

 

 

 

 

Load Buffer 0 with one word

0b010

0b0000

Virtual address

 

 

 

 

Load Buffer 0 with four words

0b010

0b0100

Virtual address

 

 

 

 

Load Buffer 0 with eight words

0b010

0b1000

Virtual address

 

 

 

 

Load Buffer 1 with one word

0b010

0b0001

Virtual address

 

 

 

 

Load Buffer 1 with four words

0b010

0b0101

Virtual address

 

 

 

 

Load Buffer 1 with eight words

0b010

0b1001

Virtual address

 

 

 

 

Load Buffer 2 with one word

0b010

0b0010

Virtual address

 

 

 

 

Load Buffer 2 with four words

0b010

0b0110

Virtual address

 

 

 

 

Load Buffer 2 with eight words

0b010

0b1010

Virtual address

 

 

 

 

Load Buffer 3 with one word

0b010

0b0011

Virtual address

 

 

 

 

Load Buffer 3 with four words

0b010

0b0111

Virtual address

 

 

 

 

Load Buffer 3 with eight words

0b010

0b1011

Virtual address

 

 

 

 

Disable user-mode MCR access

0b100

0b0000

Ignored

 

 

 

 

Enable user-mode MCR access

0b101

0b0000

Ignored

 

 

 

 

See Chapter 6, “Caches, Write Buffer, and Read Buffer” for details on the use and operation of the read buffer.

5.2.11Registers 10 – 12 RESERVED

Accessing any of these registers yields unpredictable results.

5-6

SA-1100 Developer’s Manual

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Intel SA-1100 manual Register 9 Read-Buffer Operations, Registers 10 12 Reserved