Sergei Shtylyov wrote:

quoted

It doesn't buy us anything in here, but it's conceivable that someone 
may want to write a driver that uses a shift in the I/O accessor 
rather than an array of port offsets,

   It wouldn't be IDE driver then, and neither it would be libata which 
also does this another way this (despite pata_platform uses shifts too 
-- not in the accessors, so no speed loss).

The device tree is not just for Linux.

quoted

equivalent of the cntlzw innstruction, and shift makes it clear that 
the stride must be power-of-two).  Plus, using shift is consistent 
with what we do on ns16550.

   Why the heck should we care about the UART code taling about IDE?!

Consistency?

   So, let me consider your argument purely speculative and invalid. ;-)

Consider it whatever you want. :-)

-Scott