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Re: what is __pa(x)

Hi,

> What is __pa(x) function, it said that it translates logical address to
> physical address by x-PAGE_OFFSET, PAGE_OFFSET is normally something
> like 0xc0000000, how can this translate? What is x input?

x is a virtual address. Virtual addresses are the physical addresses 
plus PAGE_OFFSET. So to go *back* to a virtual address from a physical 
address as the __pa macro does, you simply do the reverse operation and 
subtract PAGE_OFFSET.

That's my understanding, anyway. I'm a newbie too and it might not be 
that simple.

Kirk

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