Dear Alan Stern,
> On Tue, 5 Jun 2012, Marek Vasut wrote:
> > > > > + /* FIXME:
> > > > > + * - it does not work for multi-phy ehci
> > > > > + * - the best place is after debounce, but I
can't get
> > > > > + * phy there
> > > > > + */
> > > > > + if ((pstatus & PORT_CSC) && ehci->transceiver) {
> > >
> > > Do the tests in the opposite order and add "unlikely":
> > > if (unlikely(ehci->transceiver &&
> > >
> > > (pstatus & PORT_CSC)) {
> > >
> > > That way it will fail more quickly on systems where it doesn't apply or
> > > for unaffected ports.
> >
> > Does this unlikely() have any effect on ARM/MIPS/PPC, where this chipidea
> > IP is used ? Or is there some x86 device sporting this IP too?
>
> I don't know what unlikely() does on architectures other than x86.
It should be optimized out to nothing on anything else but x86. On x86 it is a
hint for the branch predictor. Or that's what I believe it is.
> And
> I haven't heard of any x86 systems that would need to use this code.
>
> On the other hand, port-status changes don't occur very frequently. A
> little time penalty one way or the other won't make much difference.
I'm not opposed, just curious :)
> Alan Stern
Best regards,
Marek Vasut
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