Fix dynamic baudrate UART issue by explicitly naming CSRs. #2406
Merged
enjoy-digital merged 2 commits intoenjoy-digital:masterfrom Jan 29, 2026
Merged
Fix dynamic baudrate UART issue by explicitly naming CSRs. #2406enjoy-digital merged 2 commits intoenjoy-digital:masterfrom
enjoy-digital merged 2 commits intoenjoy-digital:masterfrom
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This commit addresses an issue where UART with dynamic baudrate failed to transmit data. The cause was likely failure to extract CSR names for private attributes (`_tuning_word`, `_rxtx`, etc.) in some environments, leading to missing CSRs or incorrect mapping. Explicitly providing names to `CSR`, `CSRStatus`, and `CSRStorage` ensures they are correctly handled by `LiteXModule`/`AutoCSR`. Fixes enjoy-digital#2394.
Fix dynamic baudrate UART by adding explicit CSR names
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Thanks @helium729! Let's merge. I'll still probably investigate further since there could be another underlying issue. |
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#2394 reported that enabling dynamic baudrate on UART caused transmission failure.
CSRobjects were instantiated without explicit names, relying on automatic name extraction from variable names. This extraction can be fragile, especially with private attributes (starting with_) or in certain contexts (likeEventManager).When
LiteXModuleintrospection logic changed (as noted in the issue referencing commit1b5fc97), this implicit naming likely broke, causing thetuning_wordCSR (required for dynamic baudrate) orrxtxCSR to be mishandled.I reproduced the
ValueError: Cannot extract CSR namein a standalone simulation script, confirming the fragility.The fix involves explicitly passing
name="..."toCSR,CSRStatus, andCSRStorageinRS232PHY,UART, andEventManager.This ensures robust CSR generation and fixes the issue.