HW_AHBPROT modification steps or guide?

Discussion in 'Wii U - Hacking & Backup Loaders' started by officialjunk, Feb 3, 2013.

  1. Maxternal

    Maxternal Peanut Gallery Spokesman

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    The nice thing about just patching the IOS is that you can use the code it already has to access the hardware. Having the PPC talk to it directly means having to write drivers from scratch.

    harder, but doable.
     
  2. Ray Lewis

    Ray Lewis Banned

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    Interesting. Mega had it sound like it did not need patches/drivers. Unless I misunderstood his post. Or he did not go inti driver detail.
     
  3. Maxternal

    Maxternal Peanut Gallery Spokesman

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    For a lot of things a driver is just a couple lines of code. For other's it's huge and complicated. Basically by "driver" I just mean you would have to tell the program how to interact with that part of the hardware instead if just asking the IOS to do it for you.
     
  4. SifJar

    SifJar Not a pirate

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    I'm going to make a wild assumption here: Presumably IOS will have already mounted /dev/flash. This would mean all the PPC code would have to do is actually read it, which unless I'm mistaken shouldn't require much code.

    Full disclaimer: I don't know if this is the case. Nor do I know how you would read it from PPC. But it seems logical to me.
     
  5. Ray Lewis

    Ray Lewis Banned

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    Thanks for explaining that. Lots of info flowing, including Marcan's twitter;-)
     
  6. davebaol

    davebaol GBAtemp Advanced Fan

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    Ok I've just looked into IOS code and they completely removed /dev/flash device from any recent ios.
    So the approach proposed by megazig is definitely the clean way to proceed.
    With AHB rights PPC can write to the NAND hw registers which are documented here: http://wiibrew.org/wiki/Hardware/NAND_Interface
    Also nand.c from mini - see http://gitweb.bootmii.org/?p=mini.git;a=summary - is a good starting point. it's basically a reverse engineered /dev/flash.
    Porting that code to PPC should be easy enough, I guess.
    Anyways I'm not really interested in, so I won't do it.
    I wanted to share though.
     
    Maxternal, Ray Lewis and damysteryman like this.
  7. damysteryman

    damysteryman I am too busy IRL these days...

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    Thanks a heap for looking into this davebaol :D
     
  8. davebaol

    davebaol GBAtemp Advanced Fan

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    You're welcome.
    I do it for fun :)
     
  9. officialjunk
    OP

    officialjunk Advanced Member

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    Thanks for everyone's insights. When I have some time I'll make an attempt. Of course I get slammed at work the moment I began to be interested in this :(
     
  10. JoostinOnline

    JoostinOnline Certified Crash Test Dummy

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    That's exactly why I quit working on [insert something complicated that I don't understand]. ;)
     
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