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During suspend/resume the irq_work is not >>> used as this has been shown to cause suspend problems for some >>> hardware. Upon resume, any pending modem control is performed. >>> >>> Note: A new __serial8250_clear_IER() is introduced for direct >>> clearing of UART_IER during console writing (which will not be >>> holding the port lock for atomic printing or KDB/KGDB). This >>> allows restoring a lockdep check to serial8250_clear_IER() in >>> a follow-up commit. >> >> This change is causing a boot regression for our Tegra20 and Tegra30 >> platforms. Reverting this on top of -next fixes the issue. Previously with >> V5 I did not see a boot issue only an issue in suspend. > > Wasn't v11 applied and not v9? Ah may be I replied to the wrong version. However, I am testing next-20260817. So whatever is in -next. >> So far the only >> interesting thing I have observed is that if I add 'keep_bootcon' to the >> command line the board does boot. > > keep_bootcon defers driver taking over, that's why it works, it uses just > simple primitives instead of full-featured driver. Yes that makes sense then. Jon -- nvpublic