L2 Cache Power Control

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Shutdown controls are provided for the 2 MB L2 cache memory with configuration support for either 512 KB, 1 MB, or 1,512 KB of L2 cache. This enables less static power consumption. The following 4-bit control register is provided for shutting down L2 cache blocks.
Table 1. L2 Cache Power Down
Register Bits Description
L2_SHUTDOWN_CR (0x174) [3:0] Configured to shutdown L2 cache blocks of Bank 0 to 3
The above 4-bit control register powers down L2 cache blocks as per the physical RAM construction represented in the following table. Each bank contains 512 KB, constructed from thirty two 2048x64 RAMs (cc_ram_x), where the size of each RAM is 16 KB.
Note: Actual RAM width is 72 bits as an additional 8 ECC bits are used per 64-bit word.
Table 2. L2 RAM Shutdown

 L2_SHUTDOWN_CR[3] L2_SHUTDOWN_CR[2] L2_SHUTDOWN_CR[1] L2_SHUTDOWN_CR [0]
Bank 0 cc_ram_24 cc_ram_16 cc_ram_8 cc_ram_0
cc_ram_25 cc_ram_17 cc_ram_9 cc_ram_1
cc_ram_26 cc_ram_18 cc_ram_10 cc_ram_2
cc_ram_27 cc_ram_19 cc_ram_11 cc_ram_3
cc_ram_28 cc_ram_20 cc_ram_12 cc_ram_4
cc_ram_29 cc_ram_21 cc_ram_13 cc_ram_5
cc_ram_30 cc_ram_22 cc_ram_14 cc_ram_6
cc_ram_31 cc_ram_23 cc_ram_15 cc_ram_7
Bank 1 cc_ram_24 cc_ram_16 cc_ram_8 cc_ram_0
cc_ram_25 cc_ram_17 cc_ram_9 cc_ram_1
cc_ram_26 cc_ram_18 cc_ram_10 cc_ram_2
cc_ram_27 cc_ram_19 cc_ram_11 cc_ram_3
cc_ram_28 cc_ram_20 cc_ram_12 cc_ram_4
cc_ram_29 cc_ram_21 cc_ram_13 cc_ram_5
cc_ram_30 cc_ram_22 cc_ram_14 cc_ram_6
cc_ram_31 cc_ram_23 cc_ram_15 cc_ram_7
Bank 2 cc_ram_24 cc_ram_16 cc_ram_8 cc_ram_0
cc_ram_25 cc_ram_17 cc_ram_9 cc_ram_1
cc_ram_26 cc_ram_18 cc_ram_10 cc_ram_2
cc_ram_27 cc_ram_19 cc_ram_11 cc_ram_3
cc_ram_28 cc_ram_20 cc_ram_12 cc_ram_4
cc_ram_29 cc_ram_21 cc_ram_13 cc_ram_5
cc_ram_30 cc_ram_22 cc_ram_14 cc_ram_6
cc_ram_31 cc_ram_23 cc_ram_15 cc_ram_7
Bank 3 cc_ram_24 cc_ram_16 cc_ram_8 cc_ram_0
cc_ram_25 cc_ram_17 cc_ram_9 cc_ram_1
cc_ram_26 cc_ram_18 cc_ram_10 cc_ram_2
cc_ram_27 cc_ram_19 cc_ram_11 cc_ram_3
cc_ram_28 cc_ram_20 cc_ram_12 cc_ram_4
cc_ram_29 cc_ram_21 cc_ram_13 cc_ram_5
cc_ram_30 cc_ram_22 cc_ram_14 cc_ram_6
cc_ram_31 cc_ram_23 cc_ram_15 cc_ram_7
Parent topic: Functional Description