Jes Sorensen wrote:
> Jamie> Many drivers use a struct to define the offsets in their I/O or
> Jamie> iomem space. E.g. acenic.c: readl(®s->CpuCtrl). We know
> Jamie> that's not portable in the sense that struct layout is not
> Jamie> guaranteed. However, provided all the fields are suitably
> Jamie> padded & aligned, it works in practice. (So far..)
>
> That is perfectly portable because that maps onto the hardware
> registers directly, the driver is not to known whether an IO spase is
> sparse or not thats handle by readl/writel. The acenic driver simply
> uses the struct to generate offsets because I find it utterly ugly to
> use a zillion defines to set all the offsets.
The reason it's not portable in _principle_ is that the mapping "list of
struct fields" -> "offsets" can vary between architectures.
-- Jamie
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This archive was generated by hypermail 2b29 : Tue Aug 15 2000 - 21:00:21 EST