On Friday 23 August 2013 11:41 AM, Sricharan R wrote: > Hi, > On Friday 23 August 2013 10:17 AM, Rajendra Nayak wrote: >> On Thursday 22 August 2013 05:03 PM, Sricharan R wrote: >>> maps crossbar number<-> to interrupt number and >>> calls request_irq(int_no, crossbar_handler,..) >> So will this mapping happen based on some data passed from DT or >> just based on whats available when the device does a request_irq()? >> >> If its based on whats available then I see an issue when you need >> to remap something thats already mapped by default (and not used) >> since you run out of all free ones. > Yes, when done based on what is available then there is a > problem when we run out of free ones because we do not > know which one to replace. I was thinking of something like > this, > 1) DT would give a list of all free ones, and also if some are > mapped as default and not used, mark those also as free. > > 2) While mapping see if it has a default mapping and use it. > otherwise, pick from free list. Since the entire DT is available to you at boot time, you should be able to find each node where interrupt-parent = <&crossbar> and then allocate one of 0-160 GIC interrupt numbers for that node, no? Where would there be a need for default mapping and remapping? From one the mails in the thread the crossbar is completely flexible - any of the 320 crossbar interrupts can be mapped to any of the 160 GIC interrupts. Any GIC interrupts left after this boot-time scan can be added to an unused list for use with runtime DT fragments (when that support comes). Sorry if I misunderstood, but above proposal sounds like maintaining a separate free interrupt lines list in DT. That will quickly go out of sync. Thanks, Sekhar -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
