lkml.org 
[lkml]   [2006]   [Dec]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [GIT PATCH] more Driver core patches for 2.6.19
    From
    Date
    On Thu, 2006-12-14 at 09:39 +1100, Benjamin Herrenschmidt wrote:
    > > No need for an ioctl. Neither for edge nor for level irqs.
    >
    > Wait wait wait... your scenario implies that the kernel has knowledge of
    > the chip to mask the irq in the chip in the first place.
    >
    > If that is the case, then you have a chip specific kernel driver,
    > yadada, the whole story is moot :-)
    >
    > We were talking about the idea of having some "generic" reflector of
    > irqs to userspace without device specific knowledge.

    Which simply is not possible, especially for shared irqs.

    Can you please elaborate why this effort is moot, instead of throwing
    the usual flamewar arguments around ?

    The concept of UIO divides the problem in two spaces:

    - kernel interface, which controls interrupts and mapping
    - user space restricted interface

    I don't see why the necessarity of a kernel stub driver is a killer
    argument. The chip internals, which companies might want to protect are
    certainly not in the interrupt registers.

    Aside of that there are huge performance gains for certain application /
    driver scenarios and I really don't see an advantage that people are
    doing excactly the same thing in out of tree hackeries with a lot of
    inconsistent user land interfaces.

    tglx



    -
    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: 2006-12-14 00:11    [W:3.047 / U:0.076 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site