Re: [PATCH 0/5] firewire: ohci: add tracepoints event for data of Self-ID DMA

[Takashi Sakamoto <o-takashi@sakamocchi.jp>]

On Wed, Jul 03, 2024 at 07:20:29AM +0900, Takashi Sakamoto wrote:
> Hi,
> 
> In IEEE 1394, Self identification process is the last step at
> bus configuration process initiated by reset. In this step, all nodes at
> the bus broadcast self-ID packet according to the new topology. In 1394
> OHCI, the contents of the self-ID packet stream are transmitted to host
> system by DMA. This is Self-ID DMA, and configured by two registers,
> signaled by an interrupt, has a format of buffer.
> 
> Software handles the interrupt, then parse the contents of self-ID packet
> stream to detect all nodes in the bus. Finally it starts any type of
> operation in the bus. Both the timing to handle the interrupt and the
> data of DMA buffer are important as a first step to use the bus.
> 
> This series of patches is to add a tracepoints event to trace the
> interrupt and the data of DMA buffer. It would be useful to diagnose
> some kind of issue related to the self-ID process; e.g. hardware quirks.
> I also expect it useful to investigate the timing issue between hardIRQ
> and softIRQ contexts to process the contents of self-ID packets.
> 
> Takashi Sakamoto (5):
>   firewire: ohci: use common macro to interpret be32 data in le32 buffer
>   firewire: ohci: use static function to handle endian issue on PowerPC
>     platform
>   firewire: ohci: add static inline functions to deserialize for Self-ID
>     DMA operation
>   firewire: ohci: use inline functions to operate data of self-ID DMA
>   firewire: ohci: add tracepoints event for data of Self-ID DMA
> 
>  drivers/firewire/.kunitconfig        |  1 +
>  drivers/firewire/Kconfig             | 16 ++++++++
>  drivers/firewire/Makefile            |  1 +
>  drivers/firewire/ohci-serdes-test.c  | 56 ++++++++++++++++++++++++++
>  drivers/firewire/ohci.c              | 60 ++++++++++++++++++++--------
>  drivers/firewire/ohci.h              | 43 +++++++++++++++++++-
>  include/trace/events/firewire_ohci.h | 54 +++++++++++++++++++++++++
>  7 files changed, 213 insertions(+), 18 deletions(-)
>  create mode 100644 drivers/firewire/ohci-serdes-test.c

Applied to for-next branch.


Regards

Takashi Sakamoto