20 Sep, 2011

1 commit


31 Mar, 2011

1 commit


28 Feb, 2011

1 commit


30 Dec, 2010

4 commits

  • Currently completed descriptors are processed in the tasklet. This can
    lead to dead lock in case of CONFIG_NET_DMA enabled (new requests are
    submitted from softirq context and dma_memcpy_to_iovec() busy loops until
    the requests is submitted). To prevent this we should process completed
    descriptors from the allocation failure path in prepare_memcpy too.

    Signed-off-by: Ilya Yanok
    Cc: Piotr Ziecik
    Signed-off-by: Grant Likely

    Ilya Yanok
     
  • MPC8308 has pretty much the same DMA controller as MPC5121 and
    this patch adds support for MPC8308 to the mpc512x_dma driver.

    Signed-off-by: Ilya Yanok
    Acked-by: Wolfgang Denk
    Signed-off-by: Grant Likely

    Ilya Yanok
     
  • Current code clears interrupt active status _after_ submitting new
    transfers. This leaves a possibility of clearing the interrupt for this
    new transfer (if it is triggered fast enough) and thus lose this
    interrupt. We want to clear interrupt active status _before_ new
    transfers is submitted and for current channel only.

    Signed-off-by: Ilya Yanok
    Acked-by: Wolfgang Denk
    Signed-off-by: Grant Likely

    Ilya Yanok
     
  • While testing mpc512x-dma driver with dmatest module I've found that
    I can hang the mpc512x-dma issuing request from multiple threads to
    the single channel.

    insmod dmatest.ko max_channels=1 threads_per_chan=16

    After investigating this case I've managed to find that this happens
    if and only if we have more than one queued requests.
    In this case the driver tries to make use of hardware scatter/gather
    functionality. I've found two problems with scatter/gather:

    1. When TCD is copied form RAM to the TCD register space with memcpy_io()
    e_sg bit eventually gets cleared. This results in only first TCD being
    executed. I've added setting of e_sg bit explicitly in the TCD registers.
    BTW, what is the correct way to do this? (How can I use setbits with bitfield
    structure?) After that hardware loads consecutive TCDs and we hit the
    second issue.

    2. Existing code clears int_maj bit in the last TCD so we never get
    an interrupt on transfer completion.

    With these fixes my tests with many threads of single channel succeed but
    tests that use many channels simultaneously still don't work reliable.

    Signed-off-by: Ilya Yanok
    Acked-by: Wolfgang Denk
    Signed-off-by: Grant Likely

    Ilya Yanok
     

06 Aug, 2010

1 commit

  • of_device is just an alias for platform_device, so remove it entirely. Also
    replace to_of_device() with to_platform_device() and update comment blocks.

    This patch was initially generated from the following semantic patch, and then
    edited by hand to pick up the bits that coccinelle didn't catch.

    @@
    @@
    -struct of_device
    +struct platform_device

    Signed-off-by: Grant Likely
    Reviewed-by: David S. Miller

    Grant Likely
     

03 Jun, 2010

1 commit


18 May, 2010

2 commits


30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

27 Mar, 2010

2 commits

  • Simple conditional struct filler to cut out some duplicated code.

    Signed-off-by: Dan Williams

    Dan Williams
     
  • Convert the device_is_tx_complete() operation on the
    DMA engine to a generic device_tx_status()operation which
    can return three states, DMA_TX_RUNNING, DMA_TX_COMPLETE,
    DMA_TX_PAUSED.

    [dan.j.williams@intel.com: update for timberdale]
    Signed-off-by: Linus Walleij
    Acked-by: Mark Brown
    Cc: Maciej Sosnowski
    Cc: Nicolas Ferre
    Cc: Pavel Machek
    Cc: Li Yang
    Cc: Guennadi Liakhovetski
    Cc: Paul Mundt
    Cc: Ralf Baechle
    Cc: Haavard Skinnemoen
    Cc: Magnus Damm
    Cc: Liam Girdwood
    Cc: Joe Perches
    Cc: Roland Dreier
    Signed-off-by: Dan Williams

    Linus Walleij
     

02 Mar, 2010

1 commit

  • Adds initial version of MPC512x DMA driver.
    Only memory to memory transfers are currenly supported.

    Signed-off-by: Piotr Ziecik
    Signed-off-by: Wolfgang Denk
    Signed-off-by: Anatolij Gustschin
    Cc: John Rigby
    Acked-by: Grant Likely
    Signed-off-by: Dan Williams

    Piotr Ziecik