[Skiboot] [PATCH] xive+phb4: Fix exposing trigger page to Linux

[Stewart Smith]

Benjamin Herrenschmidt <benh at kernel.crashing.org> writes:
> We currently don't expose the trigger page of MSIs to Linux which
> breaks re-sending of a queued one. To fix that properly we need
> to understand out a subtle API complication:
>
>  - The "internal" XIVE_SRC_TRIGGER_PAGE indicates that a trigger
> page is supported, whether it's the same page as the EOI page
> or not.
>
>  - The "external" OPAL_XIVE_IRQ_TRIGGER_PAGE indicates that a
> *separate* trigger page exists. To know if triggers are supported
> the caller should simply check if a valid (non-0) value is returned
> in "out_trig_page" of opal_xive_get_irq_info().
>
> So PHB4 must set XIVE_SRC_TRIGGER_PAGE for MSIs and the xive code
> needs to do the "right" thing for setting whether
> OPAL_XIVE_IRQ_TRIGGER_PAGE should be set or not.
>
> Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> ---
>  hw/phb4.c      |  3 ++-
>  hw/xive.c      | 15 ++++++++++++---
>  include/xive.h | 14 +++++++++-----
>  3 files changed, 23 insertions(+), 9 deletions(-)

Thanks, merged to master as of 0bca35a2570f1dc24c8eb6a36113e7bce28bdc99
-- 
Stewart Smith
OPAL Architect, IBM.