AS_Cryptographic co-processor (C3)
RM0082
382/844
Doc ID 018672 Rev 1
Instruction Word 0-3 Register (ID_IRn)
Instruction Word Registers are used to read back the OP Code of the current executing
instruction. The instruction can be 1 to 4 words long. IR1-3 contents are undefined for 1
word instructions, IR2-3 contents are undefined for 2 word instructions and, similarly, IR3 is
undefined for 3 word instructions. These register are used mainly in Single Step Mode to
read back the last executed instruction.
21.6.18
Channel registers (C3_CHn)
Each Channel has its own specific set of registers. See the Channel User Manual to know
more about them. There is however one register that is mandatory to each Channel: the
Channel Identity Register (CH_ID). This read-only register is mapped in a fixed location and
it is typically used by the SW (at system startup) to know which Channels are available in
the C3.
Register Configuration
summarizes AHB mapped registers for a Channel (CH).
21.6.19 Channel
ID
register (CH_ID)
The Channel ID register contains the Identifier of the Channel. The Software knows that a
Channel is not present reading zero from this register (or using the ID_SCR or the
SYS_SCR). The Channel ID has no bit-field structure: the value is a mere index in a
database table.
The database containing all the assigned IDs is provided in a separate document
[CH_ID_TABLE].
There is a unique 32 bit channel ID associated to a channel/version pair. In order to avoid
using an already allocated channel ID new channel developers should contact the C3
project team to obtain unique numbers for their channels. Such centralized allocation enable
maintaining interoperability between all channel libraries and the baseline C3 platform.
Before designing a new Channel please consider looking at this table to see if a Channel
that performs a similar function does not already exist.
21.7 Channel
ID
Each Channel/Version is assigned a unique 32 bit Identifier that can be read in the Channel
ID register of each channel.
The upper 8 bit of the Channel ID are reserved for specific organizations. In order to
manage the situation in which different versions of the same channel are developed by
different company organizations the organization specific bit indicates which organization is
Table 315.
AHB mapped registers for Channel (CH)
Symbol
Name
Type
Initial Value
Address
Channel Specific
Registers
-
-
0x000-0x3FB
CH_ID
Channel ID
RO
CH_ID
0x3FC