RM0082
AS_Cryptographic co-processor (C3)
Doc ID 018672 Rev 1
403/844
Bit 31 to 30 - Channel Status (CS)
These two bits represent the status of the Channel. The status is reported to the Instruction
Dispatcher (which also duplicates this information in its bits SCR_CnS).
When the UHH Channel goes in error state, bits 29 to 24 indicates the cause. The only way
to get out from error state is to reset the channel using bit 16 (SCR_RST) or requesting an
asynchronous reset of the whole C3.
Bit 29 - Bus Error (BERR)
Every module attached to the HIF receives its own Bus error signal. This signal is set by the
HIF if a bus error condition is detected for a Bus transaction initiated by the corresponding
module. If the UHH Channel detects a bus error condition it goes in error state and this bit is
set.
Bit 28 - Dispatching Protocol Error (DERR)
If the Instruction Dispatcher goes in error state or if it is reset while it is dispatching
instruction to the UHH Channel, a dispatching protocol violation could happen. If this is the
case the UHH Channel goes in error state and this bit is set. Example: the ID has
dispatched the first word of the Hash Append instruction. The UHH Channel is still waiting
for the second word. If the ID goes now in error state (that is. because of a bus error), the
UHH Channel will never receive that second word. This condition is detected and reported
using this bit.
Bit 27 - Couple/Chaining Error (PERR)
The UHH Channel is NOT able to become a Master for Chaining operations. It is NOT able
to become simultaneously a Master and a Slave for Coupling operations.
Bit 31 CSH
Bit 30 CSL
Description
0
0
Not Present: This Channel does not exist in Hardware.
1
0
Idle: The Channel is idle and instructions can be dispatched to it.
1
1
Busy: The Channel is executing instructions dispatched by an
Instruction Dispatcher.
0
1
Error: The Channel is in error state, use Channel registers to know
the cause.
Bit 29 BERR
Description
1’b1
The HIF reported a bus error condition for a transaction initiated
by the UHH Channel.
Bit 28 DERR
Description
1’b1
The UHH Channel detected a dispatching protocol violation.
1’b0
(Clearing conditions) This flag is cleared in two ways: resetting
the UHH Channel or requesting an asynchronous master reset.