[PATCH 01/10] dt/bindings: add passthru-mask property to versatile-fpga-irq

On Fri, May 23, 2014 at 7:46 AM, Linus Walleij [off-list ref] wrote:

On Tue, May 20, 2014 at 11:09 PM, Rob Herring [off-list ref] wrote:

quoted

From: Rob Herring <robh@kernel.org>

Add a passthru-mask property for setting interrupts which are passed
through directly to a primary controller.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Pawel Moll <redacted>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <redacted>
Cc: Kumar Gala <redacted>
---
 Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt
index c9cf605..956b71d 100644
--- a/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt
+++ b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt

@@ -34,3 +34,6 @@ Optional properties:
 - interrupts: if the FPGA IRQ controller is cascaded, i.e. if its IRQ
   output is simply connected to the input of another IRQ controller,
   then the parent IRQ shall be specified in this property.
+- passthru-mask: a u32 number representing a bit mas determining which of

bit mask

(speling)

quoted

+  the interrupts are directly passed through to the primary interrupt
+  controller.

This is very confusing on the Integrators. The FPGA IRQ controller
*is* the primary interrupt controller on these.

Yes. Really, the h/w is not the same and we should have different
compatible strings. Unfortunately, it is Integrator that should
change.

(Further on Integrators with an IM-PD1 expansion board the
VIC is actually the secondary controller visavis the FPGA
IRQ controller which is the primary one.)

So on the versatile the FPGA IRQ controller is *not* cascaded
off one line of the VIC but rather connected in parallel or
something?

See figure in 3.10 of the user guide:

http://infocenter.arm.com/help/topic/com.arm.doc.dui0225d/DUI0225D_versatile_application_baseboard_arm926ej_s_ug.pdf

It is both chained and direct connection. I guess we could just use
chained mode to simplify things.

Care to elaborate a bit on how things are cascaded here?
And specify that this is for some special usecase or
something?

I'll add a reference to the user guide to the binding.

Rob