On 04/04/2019 16:58, Lina Iyer wrote: > On Mon, Mar 18 2019 at 11:54 -0600, Marc Zyngier wrote: >> On Wed, 13 Mar 2019 15:18:37 -0600 >> Lina Iyer <ilina@xxxxxxxxxxxxxx> wrote: >> >> Please do Cc Rob when posting DT related patches. >> >>> Some interrupt controllers in a SoC, are always powered on and have a >>> select interrupts routed to them, so that they can wakeup the SoC from >>> suspend. Add wakeup-parent DT property to refer to these interrupt >>> controllers. >>> >>> If the interrupts routed to the wakeup parent are not sequential, than a >>> map needs to exist to associate the same interrupt line on multiple >>> interrupt controllers. Providing this map in every driver is cumbersome. >>> Let's add this in the device tree and document the properties to map the >>> interrupt specifiers >>> >>> Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx> >>> --- >>> Changes in v4: >>> - Added this documentation >>> --- >>> .../interrupt-controller/interrupts.txt | 39 +++++++++++++++++++ >>> 1 file changed, 39 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt b/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt >>> index 8a3c40829899..917b598317f5 100644 >>> --- a/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt >>> +++ b/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt >>> @@ -108,3 +108,42 @@ commonly used: >>> sensitivity = <7>; >>> }; >>> }; >>> + >>> +3) Interrupt wakeup parent >>> +-------------------------- >>> + >>> +Some interrupt controllers in a SoC, are always powered on and have a select >>> +interrupts routed to them, so that they can wakeup the SoC from suspend. These >>> +interrupt controllers do not fall into the category of a parent interrupt >>> +controller and can be specified by the "wakeup-parent" property and contain a >>> +single phandle referring to the wakeup capable interrupt controller. >>> + >>> + Example: >>> + wakeup-parent = <&pdc_intc>; >>> + >>> + >>> +4) Interrupt mapping >>> +-------------------- >>> + >>> +Sometimes interrupts may be detected by more than one interrupt controller >>> +(depending on which controller is active). The interrupt controllers may not >>> +be in hierarchy and therefore the interrupt controller driver is required to >>> +establish the relationship between the same interrupt at different interrupt >>> +controllers. If these interrupts are not sequential then a map needs to be >>> +specified to help identify these interrupts. >>> + >>> +Mapping the interrupt specifiers in the device tree can be done using the >>> +"irqdomain-map" property. The property contains interrupt specifier at the >>> +current interrupt controller followed by the interrupt specifier at the mapped >>> +interrupt controller. >>> + >>> + irqdomain-map = <incoming-interrupt-specifier mapped-interrupt-specifier> >>> + >>> +The optional properties "irqdomain-map-mask" and "irqdomain-map-pass-thru" may >>> +be provided to help interpret the valid bits of the incoming and mapped >>> +interrupt specifiers respectively. >>> + >>> + Example: >>> + irqdomain-map = <22 0 &intc 36 0>, <24 0 &intc 37 0>; >>> + irqdomain-map-mask = <0xff 0>; >>> + irqdomain-map-pass-thru = <0 0xff>; >> >> >> This doesn't quite explain how the mask and pass-thru properties are >> used. I guess that the mask is used to define the 'useful bits' on the >> incoming side, but pass-thru puzzles me. In your example, does it mean >> that incoming lines map to outgoing interrupt <0 0>? >> > Sorry about the late reply. > > How about this to go with the rest of the documentation - > > In the above example, the input interrupt specifier map-mask <0xff 0> applied > on the incoming interrupt specifier of the map <22 0>, <24 0>, returns the > input interrupt 22, 24 etc. The second argument being irq type is immaterial > from the map and is used from the incoming request instead. The pass-thru > specifier parses the output interrupt specifier from the rest of the unparsed > argments from the map <&intc 36 0>, <&intc 37 0> etc to return the output > interrupt 36, 37 etc. I think you need to add #interrupt-cells in your example, which is otherwise hard to interpret. Thanks, M. -- Jazz is not dead. It just smells funny...
