Replace 'halted' signal with 'inhibit' vector #216
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| provided, it is strongly recommended that Debug mode can be signalled | ||
| via a 3-bit *privilege* signal. This will allow tracing in Debug mode to | ||
| be controlled via the optional filtering capabilities. | ||
| |*inhibit*[1:0] | O | The 2-bit vector controls trace inhibition. When |
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This looks fine. Because the line-breaks have moved the diff appears to show more changes than have actually been made. When the final PR against HTI is done, please try to retain as many of the existing line breaks as possible.
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Thanks! Will pay attention to it.
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| Note: if the *halted* or *reset* sideband signals are asserted (see | ||
| Note: if the *inhibit* vector indicates tracing inhibition or *reset* signal is asserted (see |
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As this will be a normative change, and will be version 2 of the HTI, we should also add a note indicating how to connect a hart with version 2 of the interface to an encoder with version 1. This can be accomplished by ORing the 2 bits of inhibit and connecting to halted.
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Sure, will add a note to suggest the connection. I am also thinking, is it a realistic case to have hart with version 1 connecting to encoder with version 2?
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Yes. For that case I think the relationship is more obvious, as the 'halted' output from the hart simply connects to bit 0 of inhibit, and bit 1 is tied low. Of course, any such system wouldn't have the ability to prevent tracing for security reasons. Or put another way, any hart implementing the secure debug extension must have a version 2 HTI.
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The "halted" sideband signal is extended to the 2-bit vector "inhibit" to indicate different stop reasons as proposed in #98
The PR is created for review purpose and not supposed to be merged.
A official PR will be proposed against Hart-Trace-Interface repo when it is established.