Eric Lee / smarc-fsl-linux-kernel

20 Jul, 2007

1 commit

13 Feb, 2007

1 commit

  • 4f423ddf5   [PATCH] EDAC: Add memory scrubbing controls API to core ... Browse Code »

    This is an attempt of providing an interface for memory scrubbing control in
    EDAC.

    This patch modifies the EDAC Core to provide the Interface for memory
    controller modules to implment.

    The following things are still outstanding:

    - K8 is the first implemenation,

    The patch provide a method of configuring the K8 hardware memory scrubber
    via the 'mcX' sysfs directory. There should be some fallback to a generic
    scrubber implemented in software if the hardware does not support
    scrubbing.

    Or .. the scrubbing sysfs entry should not be visible at all.

    - Only works with SDRAM, not cache,

    The K8 can scrub cache and l2cache also - but I think this is not so
    useful as the cache is busy all the time (one hopes).

    One would also expect that cache scrubbing requires hardware support.

    - Error Handling,

    I would like that errors are returned to the user in "terms of file
    system".

    - Presentation,

    I chose Bandwidth in Bytes/Second as a representation of the scrubbing
    rate for the following reasons:

    I like that the sysfs entries are sort-of textual, related to something
    that makes sense instead of magical values that must be looked up.

    "My People" wants "% main memory scrubbed per hour" others prefer "%
    memory bandwidth used" as representation, "bandwith used" makes it easy to
    calculate both versions in one-liner scripts.

    If one later wants to scrub cache, the scaling becomes wierd for K8
    changing from "blocks of 64 byte memory" to "blocks of 64 cache lines" to
    "blocks of 64 bit". Using "bandwidth used" makes sense in all three cases,
    (I.M.O. anyway ;-).

    - Discovery,

    There is no way to discover the possible settings and what they do
    without reading the code and the documentation.

    *I* do not know how to make that work in a practical way.

    - Bugs(??),

    other tools can set invalid values in the memory scrub control register,
    those will read back as '-1', requiring the user to reset the scrub rate.
    This is how *I* think it should be.

    - Afflicting other areas of code,

    I made changes to edac_mc.c and edac_mc.h which will show up globally -
    this is not nice, it would be better that the memory scrubbing fuctionality
    and interface could be entirely contained within the memory controller it
    applies to.

    Frithiof Jensen

    edac_mc.c and its .h file is a CORE helper module for EDAC
    driver modules. This provides the abstraction for device specific
    drivers. It is fine to modify this CORE to provide help for
    new features of the the drivers

    doug thompson

    Signed-off-by: Frithiof Jensen
    Signed-off-by: doug thompson
    Acked-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Frithiof Jensen
     

11 Jul, 2006

1 commit

  • 49c0dab7e   [PATCH] Fix and enable EDAC sysfs operation ... Browse Code »

    When EDAC was first introduced into the kernel it had a sysfs interface,
    but due to some problems it was disabled in 2.6.16 and remained disabled in
    2.6.17.

    With feedback, several of the control and attribute files of that interface
    had some good constructive feedback. PCI Blacklist/Whitelist was a major
    set which has design issues and it has been removed in this patch. Instead
    of storing PCI broken parity status in EDAC, it has been moved to the
    pci_dev structure itself by a previous PCI patch. A future patch will
    enable that feature in EDAC by utilizing the pci_dev info.

    The sysfs is now enabled in this patch, with a minimal set of control and
    attribute files for examining EDAC state and for enabling/disabling the
    memory and PCI operations.

    The Documentation for EDAC has also been updated to reflect the new state
    of EDAC operation.

    Signed-off-by:Doug Thompson
    Cc: Greg KH
    Cc: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Doug Thompson
     

27 Mar, 2006

1 commit

19 Jan, 2006

1 commit

  • da9bb1d27   [PATCH] EDAC: core EDAC support code ... Browse Code »

    This is a subset of the bluesmoke project core code, stripped of the NMI work
    which isn't ready to merge and some of the "interesting" proc functionality
    that needs reworking or just has no place in kernel. It requires no core
    kernel changes except the added scrub functions already posted.

    The goal is to merge further functionality only after the core code is
    accepted and proven in the base kernel, and only at the point the upstream
    extras are really ready to merge.

    From: doug thompson

    This converts EDAC to sysfs and is the final chunk neccessary before EDAC
    has a stable user space API and can be considered for submission into the
    base kernel.

    Signed-off-by: Alan Cox
    Signed-off-by: Adrian Bunk
    Signed-off-by: Jesper Juhl
    Signed-off-by: doug thompson
    Signed-off-by: Pavel Machek
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox