I'm sure other driver writers have hit similar problems
before. What can I do to fix this?
Sometimes I wish people who make such cards would think twice about
putting such restrictions into their PCI addressing logic, even for
boot time microcode loading operations.
I say this, because cards like the one you are working on can thus
_never_ work in an UltraSparc/PCI based system, because on such
systems, in the PCI DMA areas the top bit needs to be set, so all such
devices which "chop off" or do not implement the higher PCI addressing
bits for bus mastering, will not work on Sparc/PCI.
Note also that this makes such cards out of spec, PCI wise.
Many PCI sound cards have these issues as well (most implement the
lower 24 bits, and use the upper bits in their DMA descriptors for
control information, supposedly to save logic gates in the hw or to
simplify it in some other way).
David S. Miller
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