Wolfgang Grandegger wrote: > >> This is an OpenPGP/MIME signed message (RFC 2440 and 3156) >> >> Philippe Gerum wrote: >>> Gilles Chanteperdrix wrote: >>>> Wolfgang Grandegger wrote: >>>> > Therefore we need a dedicated function to re-enable interrupts in >>>> the > ISR. We could name it *_end_irq, but maybe *_enable_isr_irq is >>>> more > obvious. On non-PPC archs it would translate to *_irq_enable. >>>> I > realized, that *_irq_enable is used in various place/skins and >>>> therefore > I have not yet provided a patch. >>>> >>>> The function xnarch_irq_enable seems to be called in only two > functions, >>>> xintr_enable and xnintr_irq_handler when the flag XN_ISR_ENABLE is set. >>>> >>>> In any case, since I am not sure if this has to be done at the Adeos >>>> level or in Xenomai, we will wait for Philippe to come back and decide. >>>> >>> ->enable() and ->end() all mixed up illustrates a silly x86 bias I once >>> had. We do need to differentiate the mere enabling from the IRQ epilogue >>> at PIC level since Linux does it - i.e. we don't want to change the >>> semantics here. >>> >>> I would go for adding xnarch_end_irq -> rthal_irq_end to stick with the >>> Linux naming scheme, and have the proper epilogue done from there on a >>> per-arch basis. >>> >>> Current uses of xnarch_enable_irq() should be reserved to the >>> non-epilogue case, like xnintr_enable() i.e. forcibly unmasking the IRQ >>> source at PIC level outside of any ISR context for such interrupt (*). >>> XN_ISR_ENABLE would trigger a call to xnarch_end_irq, instead of >>> xnarch_enable_irq. I see no reason for this fix to leak to the Adeos >>> layer, since the HAL already controls the way interrupts are ended >>> actually; it just does it improperly on some platforms. >>> >>> (*) Jan, does rtdm_irq_enable() have the same meaning, or is it intended >>> to be used from the ISR too in order to revalidate the source at PIC > level? >> Nope, rtdm_irq_enable() was never intended to re-enable an IRQ line >> after an interrupt, and the documentation does not suggest this either. >> I see no problem here. > > But RTDM needs a rtdm_irq_end() functions as well in case the > user wants to reenable the interrupt outside the ISR, I think.
If this is a valid use-case, it should be really straightforward to add this abstraction to RTDM. We should just document that rtdm_irq_end() shall not be invoked from IRQ context - to avoid breaking the chain in the shared-IRQ scenario. RTDM_IRQ_ENABLE must remain the way to re-enable the line from the handler. Jan
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