[Sound-open-firmware] [PATCH 00/25] add R/W pointers check for pipeline buffers

Keyon Jie yang.jie at linux.intel.com
Tue Feb 7 15:02:47 CET 2017


This series adding the R/W buffer pointers check and make sure we won't
copy wrong/missed/repeated data for the whole pipeline.

For ALSA applications, usually we have two kinds of trigger command sequences:
1. (e.g. aplay) prefill datas ==> trigger start ==> refill buffer(when buffer
        free is enough) ==> ... ==> data filling finished ==> trigger drain ==>
        when all datas are rendered(via read pointer feedback) ==> trigger stop;
2. (e.g. speaker-test with large buffer size > wav file size):
        prefill all datas one time ==> trigger start ==> wait until all datas are
        rendered(via feedback read pointer) ==> trigger stop ==> prefill another
        wav file ==> trigger start ==> ...

So the feedback from firmware about the read pointer is very important for
the pipeline's running, to make the firmware can handle these two kinds of
sequences, this series design/assume with preconditions:

1. We do down stream full preload(full fill all pipeline buffers, except host
side one);
2. Using pull mode at running stage and pulling one period per time;
3. When in normal running status, if buffer a->avail is 0, then all those
upstream buffers are empty;

For those two sequence, we use a same logic to handle it:

1. We put all components in running status even some of them are empty(dai is
an exception);
2. We stop dai/ssp once we found there is no more data for it to render, and
notify this last read position to host side;
3. Host side will trigger stop and we will reset all buffer pointers and
related resources;
4. For case #1, trigger reset will reset/free more resources(allocated/init
in set_params()); For case #2, another start cmd will trigger preload and start
in firmware, before that all pointers are reset to original ones.

TODOs: It is only verified for playback, for capture, we may need some vivid
code to implement them.

Keyon Jie (25):
  host: handle more possibility for playback spitting
  dai: reset dai_pos at MMAP_PPOS command
  pipleline: op_sink: don't need clear the buffer for each prepare
  host: start: don't real start for start command
  ipc: presentation_posn should be uint64_t type
  intel-ipc: add application buffer pointer update from host side
  intel-ipc: add stream operation IPC_INTEL_STR_STOP
  host: add host_update_buffer for produce and consume
  host: rename host_pos_blks to host_pos_read
  host: for the last bytes/period, send read notification later
  host: add R/W pointers check for playback
  host: add a completion work to notify host side
  host: reset pointers at new() and reset()
  host: cleanup host_cmd() cases
  host: host_copy: only copy when there is data and wait until finish
  volume: volume_params(): set the sink buffer params depending on its
    sink
  component: status: rename COMP_STATE_STOPPED to COMP_STATE_SETUP
  volume: volume_cmd(): only stop/pause at running
  volume: add R/W pointer check for volume_copy()
  mixer: mixer_params(): set the sink buffer params to
    STREAM_FORMAT_S32_LE.
  mixer: add R/W pointer check for mixer_copy()
  mixer: add dd->last_bytes for the last bytes(< period) caculation
  dai: add R/W pointer check for dai copy
  dw-dma: handle different cases in irq handler
  component: host/volume/mixer: reset buffers for stop cmd

 src/audio/dai.c                                   |  60 ++++-
 src/audio/host.c                                  | 289 +++++++++++++++++-----
 src/audio/mixer.c                                 |  64 ++++-
 src/audio/pipeline.c                              |  11 +-
 src/audio/volume.c                                |  66 ++++-
 src/drivers/dw-dma.c                              |  25 +-
 src/include/reef/audio/component.h                |   6 +-
 src/include/reef/audio/pipeline.h                 |   2 +
 src/include/reef/dma.h                            |   6 +
 src/include/uapi/intel-ipc.h                      |   4 +-
 src/ipc/intel-ipc.c                               |  77 ++++++
 src/platform/baytrail/include/platform/platform.h |   6 +
 12 files changed, 511 insertions(+), 105 deletions(-)

-- 
2.7.4



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