On Tue Jun 14 11, Hans Petter Selasky wrote:
> On Tuesday 14 June 2011 14:52:08 Alexander Motin wrote:
> > Hans Petter Selasky wrote:
btw., if i might ask a technical and probably naive question:
does USB 3.0 feature *full* backward compatibility? that is supporting usb 1.x
and usb 2.0 devices without the need for enabling those legacy controllers?
so will xhci give me all the backward compatibility or do i have to also enable
a combination of ohci/uhci/ehci? with usb 2.0 there was no usb 1.x support
unless ohci/uhci was also enabled.
i read that the xhci controllers don't depend on CPU and I/O availability as
much as the old controllers. doing CPU intensive tasks shouldn't have such a
massive effect on USB transfer times, compared to usb 1.x and 2.0. that's why
i'd like to completely get rid of the need for ohci/uhci/ehci in my kernel
i'd really like to see some transfer time statistics with CPU being close to
100% idle and with CPU being hammered close to 100% with usb 3.0. i think i did
such a test a while ago for usb 2.0 and transfer rates dropped quite
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