Architecture Overview
MSC8144E Reference Manual, Rev. 3
Freescale Semiconductor
26-5
26.1.3 Channels
The SEC includes four channels that manage data and EU function. Each channel contains the
following:
Fetch FIFO. Holds a queue of pointers to descriptors waiting to be serviced.
Configuration register. Allows the user a number of options for SEC event signalling.
Control registers. Information about the transaction in process.
Status register. Indicates the last unfulfilled bus request.
Descriptor buffer memory. Stores the active descriptor.
26.1.3.1 Channel Servicing
Whenever a channel is idle and its Fetch FIFO is non-empty, the channel reads the next
descriptor pointer from the Fetch FIFO. Using this pointer, the channel fetches the descriptor and
places it in its descriptor buffer. To service this descriptor, the channel directs execution of the
following steps.
1.
Analyze the descriptor header to determine the cryptographic services required, and
request use of the appropriate EUs from the controller.
2.
Wait for the controller to grant access to the required EUs.
3.
Set the appropriate mode bits in the EU(s) for the required service.
4.
Fetch data parcels using pointers from the descriptor buffer, and place them in either an
EU input FIFO or EU registers (as appropriate). The term data parcel refers here to any
input or output of a cryptographic process, such as a key, hash result, input context,
output context, or text-data. Context refers to either an initialization vector (IV) or other
internal EU state that can be read out or loaded in. Text-data refers to the plaintext or
ciphertext on which to operate.
5.
If the data size is greater than EU FIFO size, continue fetching input data and writing
output data to memory.
6.
Wait for EU(s) to complete processing.
7.
Upon completion, unload results from output FIFOs and Context Registers and write
them to external memory using pointers in the descriptor buffer.
8.
If multiple services are requested, go back to step 4. If not, continue to step 9.
9.
Release the EUs.
10.
If done notification is enabled, perform this notification.
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...