[Skiboot] (no subject)

Jack Miller jack at codezen.org
Fri Aug 5 03:48:53 AEST 2016


On Thu, Aug 04, 2016 at 05:17:07PM +1000, Cyril Bur wrote:
> Recently Mikey wrote quite a lot to get everything working 64bit, which made
> this catch my eye. Don't we want #size-cells, 1 (or 2... ...) and
> #address-cells, 0? What we're going to write in there is the size.
> 
> I think the fact that both "dt_add_property_cells()" and the powernv-flash
> driver in linux ignore the #size-cells/#address-cells props means that it is
> working but I dread to think what happens if we do respect them. On >32bit
> flashes (mambo bogusdisk flashes) 2x32bit cells written in regs which when
> interpreted as one 64bit number makes the correct size. 
> 
> Probably easiest to use 2 for #size-cells? Although then we'd need to ensure
> dt_add_property_cells(); gets that right for flashes <32bit.
> 
> Looking more into dt_add_property_cells() using it to write >32bit values is
> probably not the way to go... I feel like that "0," in the call is saving us.

I'll admit that I'm a bit cynical about these properties since, as you
mention, they get ignored pretty much universally, but I think you're right.
#size-cells = 2 and #address-cells = 0 makes the most sense with what we're
actually writing into reg, and still fixes the dtc warning. Patch tweaked.

- Jack



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