10.5.1. Authentication signals

Table 10.19 shows a list of the valid combinations of authentication signals along with their associated debug permissions.

Table 10.19. Authentication signal restrictions

SPIDENDBGEN[a]SPNIDENNIDENSecure[b] invasive debug permittedNon-secure invasive debug permittedSecure non-invasive debug permittedNon-secure non-invasive debug permitted
0000NoNoNoNo
0001NoNoNoYes
0010NoNoNoNo
0011NoNoYesYes
0100NoYesNoYes
0101NoYesNoYes
0110NoYesYesYes
0111NoYesYesYes
1000NoNoNoNo
1001NoNoYesYes
1010NoNoNoNo
1011NoNoYesYes
1100YesYesYesYes
1101YesYesYesYes
1110YesYesYesYes
1111YesYesYesYes

[a] When DBGEN is LOW, the processor behaves as if DSCR[15:14] equals b00 with the exception that halting debug events are ignored when this signal is LOW.

[b] Invasive debug is defined as those operations that affect the behavior of the core. For example, taking a breakpoint is defined as invasive debug but performance counters and trace are noninvasive.


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