[RFC PATCH v2 0/5] Rework realtek-rtl IRQ driver

[Sander Vanheule <sander@svanheule.net>]

After seeing some use, and with more devices tested, the current
implementation for the Realtek SoC interrupt controller was found to
contain a few flaws.

The driver requires the following fixes:
- irq_domain_ops::map should map the virq, not the hwirq (patch 1)
- routing has an off-by-one error. Routing values (1..6) correspond to
  MIPS CAUSEF(2..7) (patch 2)

The following improvements should also be made:
- Use N real cascaded interrupts with an interrupt-specific mask of
  child irq lines. Otherwise a high-priority interrupt may cause a
  low-priority interrupt to be handled first. (patch 3)
- Get rid of assumed routing to parent interrupts of the original
  implementation (patch 4, 5)

Changes since v1:
Link: https://lore.kernel.org/all/cover.1640261161.git.sander@svanheule.net/

Still an RFC. Mainly since I don't like the open coding in the last
patch, but also since I still have a question about the chained IRQ
handlers.

- Split some of the changes to limit the patch scope to one issue.
- Dropped some small (spurious or unneeded) changes
- Instead of dropping/replacing interrupt-map, the last patches now
  provide an implementation that amends the current situtation.

Sander Vanheule (5):
  irqchip/realtek-rtl: map control data to virq
  irqchip/realtek-rtl: fix off-by-one in routing
  irqchip/realtek-rtl: use per-parent irq handling
  dt-bindings: interrupt-controller: realtek,rtl-intc: map output lines
  irqchip/realtek-rtl: add explicit output routing

 .../realtek,rtl-intc.yaml                     |  38 ++-
 drivers/irqchip/irq-realtek-rtl.c             | 232 ++++++++++++++----
 2 files changed, 218 insertions(+), 52 deletions(-)

-- 
2.33.1