ARM r1p3, R4F manual ARM DDI 0363E

Level Two Interface

Table 9-38 Tag register format for reads, with ECC (continued)

Data bit	Description
[31:30]	Not used, read-as-zero
[29:23]	ECC, way 0/1
[22]	Valid, way 0/1
[21:0]	Tag value, way 0/1

Table 9-39 Tag register format for writes, no parity or ECC

Data bit	Description
[63:23]	Not used, read-as-zero
[22]	Valid, all ways
[21:0]	Tag value, all ways

Table 9-40 Tag register format for writes, with parity

Data bit	Description
[63:24]	Not used, read-as-zero
[23]	Parity. all ways
[22]	Valid, all ways
[21:0]	Tag value, all ways

Table 9-41 Tag register format for writes, with ECC

Data bit	Description
[63:30]	Not used, read-as-zero
[29:23]	ECC, all ways
[22]	Valid, all ways
[21:0]	Tag value, all ways

Note

For tag RAM writes, only bits [23:0] of the data bus are used. If two tag RAMs are written at the same time, they are both written with the same data. To write only one tag RAM using the AXI Slave, select only one RAM with bits [18:15] of the address bus.

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