lkml.org 
[lkml]   [2005]   [Nov]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 4/5] Centralise NO_IRQ definition

    * Paul Mackerras <paulus@samba.org> wrote:

    > Ingo Molnar writes:
    >
    > > is there any architecture where irq 0 is a legitimate setting that could
    > > occur in drivers, and which would make NO_IRQ define of 0 non-practical?
    >
    > Yes, G5 powermacs have the SATA controller on irq 0. So if we can't
    > use irq 0, I can't get to my hard disk. :) Other powermacs also use
    > irq 0 for various things, as do embedded PPC machines.

    oh well [*]. Then it's gotta be the !dev->irq.valid thing i guess. OTOH
    that has some disadvantages too: any normal access to dev->irq.nr will
    mean implicit 0xffffffff (or 0xffffffffffffffff) masking generated by
    the compiler. Also, unless there's some compiler trick, tons of drivers
    will be affected - because dev->irq isnt valid anymore. A quick grep
    suggests 5381 lines of code affected, spread out in 917 files. Quite
    impractical. So we are back to square one and Matthew's patch(es).

    Ingo

    [*] is there any weird architecture that hardcodes IRQ -1 to some
    device? ;-)
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-11-21 22:39    [W:0.021 / U:1.320 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site