[lkml]   [1999]   [Aug]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: New resources - pls, explain :-(
    On Wed, Aug 11, 1999, Alan Cox <> wrote:

    >Its cute but if you think harder the implementation would suck
    >> right thing" for that bus. One could add "bigendian_writel()" and
    >> "littleendian_writel()" to satisfy the Linus constraint of making
    >> unusual usage of writel() obvious.
    >So every I/O has an if in it. Nothing like stalling the pipeline before we
    >probably stall on I/O writes to make things twice as painful.

    And what about simply having a struct io_bus containing function pointers
    to read/write and ioremap routines ? This way, we could hide all the i/o
    range offset issues when using several busses (we do have such problems
    with the ppc, especially with IDE, see recent discussion of linuxppc-dev
    mailing list). Each driver would have an bus structure associated with
    the device, eventually provided by the resource tree, and the only
    overhead of i/os could be the indirect function call.

    For the endian issue (which I think is a non-issue) , most of the time,
    the endian is known at compile time and could get be resolved by macros.
    If it's not the case, then just add two sets of i/o function pointers in
    the bus structure.

    Also, each bus stucture (let's call this a bus driver) can have it's own
    alloc/dealloc range functions associated, and eventually generic
    notifiers for hotswap.

    I beleive we can build some kind of "device-tree" which would be made of
    a virtual root, containing busses, containing resources trees. Looks a
    bit like Open Firmware ;-)

    Perso. e-mail: <>
    Work e-mail: <>
    BenH. Web : <>

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:53    [W:0.020 / U:6.512 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site