Hello On Mon, Aug 10, 2009 at 11:07 PM, Basavaraj Dengi<basavarajdengi@xxxxxxxxx> wrote: > I am porting 'kdb' to omap3430 platform. > for command 'mdp arg' [mdp is memory dump physical and arg is any physical > address] this code gets executed. I dint test for every address b/w > 0-0xc0000000 > but lots of them randomnly. The other 'md' commands do work for kernel high > memory address.[ie. > 0xc0000000] But mdp fails for all the addresses. > > this piece of code is part of architecture independant patch of kdb; [for > 2.6.24 kernel] > kdb community is very inactive and moreover this question is related to > memory management part of the kernel, so I thought i will ask it here I have no experience about embedded development at all, including Omap. But questions that cross my mind are: 1. Is Omap MMU or MMU less? If it is MMU-less, I think talking about page frame is completely irrelevant here. Or at least MMU related functions will try to "emulate" the MMU situation, but still not the same as MMU based arch 2. Still related with above question, perhaps this Omap arch implement kinda "memory hole"? So not every memory address range is mapped? 3. Does Omap use memory split like x86 does? I mean 3:1 for user space:kernel space? The possibility that some "md" commands doesn't work when dealing with address below kernel space range is it has to grab the page directory of current running process and does the translation based on this PGD (again, assuming Omap is using MMU). And this grabbing mechanism is either unimplemented yet or has some bugs. My thoughts might have flaws, so feel free to debate them. -- regards, Mulyadi Santosa Freelance Linux trainer blog: the-hydra.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
