Hi Albert, On 22.06.2013 11:58, Albert ARIBAUD wrote: > From time to time there is discussion about the need for proper > interrupt support in U-Boot. > > Right now, the only thing left in the source code which remotely looks > like interrupt support is a few code sections compiled conditionally > under CONFIG_USE_IRQ, and it does not constitute a good approach to > interrupt support, if only for the following reasons: > > - CONFIG_USE_IRQ is very general and imprecise as far as overall > meaning goes. It does not say "allow drivers to use IRQs", or "IRQs > are provided by supporting this specific interrupt controller", or > "this driver requires IRQs to work". It does not help us either that > the option was never documented... > > - CONFIG_USE_IRQ is, OTOH, very specific as far as interrupt types go. > IRQ is an acronym known in ARM for a specific type of interrupt, but > ARM also knows FIQ. IRQ may have a different meaning for another > architecture, and each platform has its own classification and > attributes for interrupts. > > - no API is defined for registering interrupt controller or interrupt > client drivers. > > But the worst part is, CONFIG_USE_IRQ is never *ever* defined. :) > > So I am tempted to start this RFC with a first question: do we *need* > interrupts in the first place, and if we do, do we need an organized > interrupts subsystem or do we keep an ad hoc approach?
I know that interrupts are currently used on PowerPC for the PPC4xx ethernet driver (emac). This could be reworked to of cause, but I just wanted to point this out. I have no idea if interrupts are used on any ARM platform though. Thanks, Stefan _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot