From mboxrd@z Thu Jan 1 00:00:00 1970 In-Reply-To: Date: Thu, 26 Aug 1999 10:44:50 +0200 To: Tony Mantler , linuxppc-dev@lists.linuxppc.org From: Benjamin Herrenschmidt Subject: Re: Performa 5200 Message-Id: <19990826104450.024993@mailhost.mipsys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Wed, Aug 25, 1999, Tony Mantler wrote: >I know the '040 maintains consistiency during the operation of alternate >bus masters by snooping and spiking the bus according to what's in the >cache. I haven't read up on how the PPC does it, but I would have expected >it to be made code-level compatible with what the 040 does, atleast in >these early PMacs. I didn't check but someone (I think Paul) told me that snooping was not done accross the PPC<->68k bus bridge used by those machines. Note that I'm working on another cache-incoherent platform, and I'm struggling with similar issues, I beleive we should manage to "officialise" some vmalloc_uncached functions in the kernel for cache-incoherent platforms (and define a standard way to tell a driver it's running on a non-coherent machines). The current macros in io.h are definitely not enough. > >Or something like that. > >Penguin collects a pile of LM globals and passes them in the bi struct, but >most of those can be implied from the gestalt machine ID. Considering the >number of NuBus PMacs, I don't think it would be terribly difficult to >guess anything that's not passed in explicitly. I think that's what MkLinux does. >But, I shan't pay any note of it 'till *after* I get a kernel to boot. :) Yep, of course ;-) -- Perso. e-mail: Work e-mail: BenH. Web : [[ This message was sent via the linuxppc-dev mailing list. Replies are ]] [[ not forced back to the list, so be sure to Cc linuxppc-dev if your ]] [[ reply is of general interest. Please check http://lists.linuxppc.org/ ]] [[ and http://www.linuxppc.org/ for useful information before posting. ]]