misc questions about the device&driver arch

william wallace avalonwallace at gmail.com
Tue May 30 07:42:27 PDT 2006

On 5/30/06, Scott Long <scottl at samsco.org> wrote:
> M. Warner Losh wrote:
> > : THIRD
> > : Because the PCIE configure space is 4k long ,shall we change the
> > : #define PCI_REGMAX  255
> > : to facilitate the PCI express config R/W?
> >
> > Maybe.  Lemme investigate because PCIe changes this from a well known
> > constant for all pci busses, to a variable one...
> >
> > Warner
> When I added PCIe extended config support, I never took into
> consderation the userland access point of view.  Changing this
> definition to 4096 might Just Work, and it might Not Work.  Dunno.
> In the 18 months since I implemented it, no other person has asked
> about userland access.  Other than the silly case of people trying
> to write device drivers in PERL, I'm not sure how much value it
> gives compared to the stability and security risk it imposes.
> Scott
I have to clarify my intentions that i am not TRYing to do a userland
PCI express driver . I just want to make a interesting branch whitch
can do pci express native Hot plug and hot remove ,with Mr Losh and
other gentlemen's help ,i am making progress ,and now a loadable
module is finishing .
I have borrowed many Ideas from Linux ,but several fatal difficulties
paused me ,with the PCI_REGMAX included.
wish to hear from u :) thank u!

we who r about to die,salute u!

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