Freescale Semiconductor MSC8144E, Reference Manual

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MSC8144E Reference Manual, Rev. 3
26-186 Freescale Semiconductor
Security Engine (SEC)
26.5.12.7 RNG End_of_Message Register (RNGEOMR)
The RNG End_of_message is a writable location but serves no function in the RNG. It is
documented for the sake of consistency with the other EUs.
26.5.12.8 RNG Output FIFO
RNG uses an output FIFO to collect periodically sampled random 64-bit-words, with the intent
that random data always be available for reading. Normally, the channels control all access to this
FIFO. For core processor-controlled operation, a read from anywhere in the RNG FIFO address
space dequeues data from the RNG output FIFO.
The output FIFO is readable by byte, 4-byte, or 8-byte accesses. When all 8 bytes of the header
are read, that 8 bytes is automatically dequeued from the FIFO so that the next 8 bytes (if any)
becomes available for reading. If any byte is read twice between dequeues, it causes an error
interrupt of type AE from the EU.
Underflows caused by reading or writing the RNG output FIFO are reflected in the RNG
Interrupt Status Register. Also, a write to the RNG output FIFO space will be reflected as an
addressing error in the RNG Interrupt Status Register.
Note: The RNG output FIFO is located at offset 0xCA800–0CAFFF.
RNGEOMR RNG End_of_ Message Register Offset 0xCA050
Bits 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48
Field —
Type W
Reset 0x0000
Bits 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
Field —
Type W
Reset 0x0000
Bits 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Field —
Type W
Reset 0x0000
Bits 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Field —
Type W
Reset 0x0000