On Mer, 2003-05-21 at 01:34, Ralf Baechle wrote:
> > of the base MIPS instruction set. If one wants to live without them,
> > one can either rig a compiler to emit multi-instruction sequences instead
> > of lwr/lwl to do the appropriate shifts and masks (which is slower on all
This would seem the sane approach.
> Technically you're right ... In reality lwl/lwr are covered by US patent
> 4,814,976 which would also cover a software implementation. So unless MIPS
> grants a license for the purpose of emulation in the Linux kernel ...
They would need to grant a license for general GPL use, the GPL itself
does not intend to allow other restrictions that would make the code non
free. There are a billion examples of prior art for software fixing up
of exceptions and software emulation of alignment fixups however.
Maybe MIPS can clarify their position officially.
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