19 Jun, 2018

2 commits


08 Jun, 2018

2 commits

  • Add timestamp to each iotrace record to aid in debugging
    of IO timing access bugs.

    Signed-off-by: Ramon Fried
    Reviewed-by: Simon Glass

    Ramon Fried
     
  • When dealing with a lot of IO regions, sometimes
    it makes sense only to trace a specific one.
    This patch adds support for region limits.
    If region is not set, the iotrace works the same as it was.
    If region is set, the iotrace only logs io operation that falls
    in the defined region.

    Signed-off-by: Ramon Fried
    Reviewed-by: Simon Glass

    Ramon Fried
     

07 May, 2018

1 commit

  • When U-Boot started using SPDX tags we were among the early adopters and
    there weren't a lot of other examples to borrow from. So we picked the
    area of the file that usually had a full license text and replaced it
    with an appropriate SPDX-License-Identifier: entry. Since then, the
    Linux Kernel has adopted SPDX tags and they place it as the very first
    line in a file (except where shebangs are used, then it's second line)
    and with slightly different comment styles than us.

    In part due to community overlap, in part due to better tag visibility
    and in part for other minor reasons, switch over to that style.

    This commit changes all instances where we have a single declared
    license in the tag as both the before and after are identical in tag
    contents. There's also a few places where I found we did not have a tag
    and have introduced one.

    Signed-off-by: Tom Rini

    Tom Rini
     

19 Apr, 2015

1 commit


21 Jun, 2014

1 commit

  • When debugging drivers it is useful to see what I/O accesses were done
    and in what order.

    Even if the individual accesses are of little interest it can be useful to
    verify that the access pattern is consistent each time an operation is
    performed. In this case a checksum can be used to characterise the operation
    of a driver. The checksum can be compared across different runs of the
    operation to verify that the driver is working properly.

    In particular, when performing major refactoring of the driver, where the
    access pattern should not change, the checksum provides assurance that the
    refactoring work has not broken the driver.

    Add an I/O tracing feature and associated commands to provide this facility.
    It works by sneaking into the io.h heder for an architecture and redirecting
    I/O accesses through its tracing mechanism.

    For now no commands are provided to examine the trace buffer. The format is
    fairly simple, so 'md' is a reasonable substitute.

    Note: The checksum feature is only useful for I/O regions where the contents
    do not change outside of software control. Where this is not suitable you can
    fall back to manually comparing the addresses. It might be useful to enhance
    tracing to only checksum the accesses and not the data read/written.

    Signed-off-by: Simon Glass

    Simon Glass