Mips Technologies R4000 - R4000 Processor Interrupts

MIPS R4000 Microprocessor User's Manual 371
System Interface
Table 12-21 Encoding of SysCmd(4:0) for External Update Requests
Table 12-22 Encoding of SysCmd(4:0) for Processor Update Requests
SysCmd(4)
Processor Unacknowledged Invalidate or
Update Cancellation
0 Invalidate or Update cancelled
1 No cancellation
SysCmd(3) Update Cache State Change Attributes
0 Cache state changed to shared
1 No change to cache state
SysCmd(2:0) Update Data Size
0 1 byte valid (Byte)
1 2 bytes valid (Halfword)
2 3 bytes valid (Tribyte)
3 4 bytes valid (Word)
4 5 bytes valid (Quintibyte)
5 6 bytes valid (Sextibyte)
6 7 bytes valid (Septibyte)
7 8 bytes valid (Doubleword)
SysCmd(4) Reserved
SysCmd(3) Update type
0 Compulsory
1 Potential
SysCmd(2:0) Update Data Size
0 1 byte valid (Byte)
1 2 bytes valid (Halfword)
2 3 bytes valid (Tribyte).
3 4 bytes valid (Word)
4 5 bytes valid (Quintibyte)
5 6 bytes valid (Sextibyte)
6 7 bytes valid (Septibyte)
7 8 bytes valid (Doubleword)