Fix a bug that causes the core to freeze when enabling CV-X-IF while disabling RVC extension #3168
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…t the RVC extension Signed-off-by: Charbel SAAD <[email protected]>
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Dec 22, 2025
| is_illegal_deco[0] = is_illegal_cvxif_i; | ||
| instruction_deco[0] = instruction_cvxif_i; | ||
| is_compressed_deco[0] = is_compressed_cvxif_i; | ||
| if (CVA6Cfg.RVC) begin |
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In order to have a cleaner code, I think these assignments should be made inside the previous if block (lines 156-281). This is only a quick fix.
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👋 Hi there! This pull request seems inactive. Need more help or have updates? Feel free to let us know. If there are no updates within the next few days, we'll go ahead and close this PR. 😊 |
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This is an attempt to fix the bug described in #3167.
It appears that when enabling the CV-X-IF interface while disabling the RVC extension, the core freezes during the initialization phase of the debug sequence in the testbench.
I managed to find out that this was caused by a bug inside the Decode stage: the compressed‑instruction channel driver of the CV-X-IF inside the Decode stage is only generated if the RVC extension is enabled. However, this module still drives signals inside the stage even when RVC is off. I proposed a fix in the PR below, although I am not sure it is the cleanest way to address the issue.