On Wed, Oct 29, 2014 at 12:53 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Tuesday 28 October 2014 20:58:57 Kevin Cernekee wrote: >> Most implementations of the bcm7120-l2 controller only have a single >> 32-bit enable word + 32-bit status word. But some instances have added >> more enable/status pairs in order to support 64+ IRQs (which are all >> ORed into one parent IRQ input). Make the following changes to allow >> the driver to support this: >> >> - Extend DT bindings so that multiple words can be specified for the >> reg property, various masks, etc. >> >> - Add loops to the probe/handle functions to deal with each word >> separately >> >> - Allocate 1 generic-chip for every 32 IRQs, so we can still use the >> clr/set helper functions >> >> - Update the documentation >> >> Signed-off-by: Kevin Cernekee <cernekee@xxxxxxxxx> > > You should probably specify a 'big-endian' DT property for the driver > to check. If you have both LE and BE versions of this device, we > must make sure that we use the correct accessors. > > As long as we don't need to build a kernel that supports both (if > I understand you correctly, the ARM SoCs use a LE instance of this > device, while the MIPS SoCs use a BE version) you can still decide > at compile-time which one you want, but please add the runtime check > now, so if we ever get a new combination we can handle it at runtime > with a more complex driver implementation. Under discussion in the other thread... > If I read your code right, you have decided to use one IRQ domain > per register set, rather than one domain for all of them. I don't > know which of the two ways is better here, but it would be good if > you could explain in the patch description why you did it like this. This uses one domain per bcm7120-l2 DT node. If the DT node defines multiple enable/status pairs (i.e. >=64 IRQs) then the driver will create a single IRQ domain with 2+ generic chips. Multiple generic chips are required because the generic-chip code can only handle one enable/status register pair per instance.
