[RESEND,00/10] Support polling for out of order completions

Message

Ben Walker Feb. 1, 2022, 8:38 p.m. UTC

This series adds support for polling async transactions for completion
even if interrupts are disabled and transactions can complete out of
order.

To do this, all DMA client assumptions about the behavior of
dma_cookie_t have to be removed. Prior to this series, dma_cookie_t was
a monotonically increasing integer and cookies could be compared to one
another to determine if earlier operations had completed (up until the
cookie wraps around, then it would break).

Fortunately, only one out of the many, many DMA clients had any
dependency on dma_cookie_t being anything more than an opaque handle.
This is the pxa_camera driver and it is dealt with in patch 3 of this
series. Please take an extra critical look at that change.

The series also does some API clean up and documents how dma_cookie_t
should behave (i.e. there are no rules, it's just a handle).

This closes out by adding support for .device_tx_status() to the idxd
driver and then reverting the DMA_OUT_OF_ORDER patch that previously
allowed idxd to opt-out of support for polling, which I think is a nice
overall simplification to the dmaengine API.

Ben Walker (10):
  dmaengine: Remove dma_async_is_complete from client API
  dmaengine: Move dma_set_tx_state to the provider API header
  dmaengine: Remove the last, used parameters in
    dma_async_is_tx_complete
  dmaengine: Remove last, used from dma_tx_state
  dmaengine: Providers should prefer dma_set_residue over
    dma_set_tx_state
  dmaengine: Remove dma_set_tx_state
  dmaengine: Add provider documentation on cookie assignment
  dmaengine: idxd: idxd_desc.id is now a u16
  dmaengine: idxd: Support device_tx_status
  dmaengine: Revert "cookie bypass for out of order completion"

 Documentation/driver-api/dmaengine/client.rst | 22 ++---
 .../driver-api/dmaengine/provider.rst         | 64 ++++++++------
 drivers/crypto/stm32/stm32-hash.c             |  3 +-
 drivers/dma/amba-pl08x.c                      |  1 -
 drivers/dma/at_hdmac.c                        |  3 +-
 drivers/dma/dmaengine.c                       |  2 +-
 drivers/dma/dmaengine.h                       | 12 ++-
 drivers/dma/dmatest.c                         | 14 +--
 drivers/dma/idxd/device.c                     |  1 +
 drivers/dma/idxd/dma.c                        | 86 ++++++++++++++++++-
 drivers/dma/idxd/idxd.h                       |  3 +-
 drivers/dma/imx-sdma.c                        |  3 +-
 drivers/dma/mmp_tdma.c                        |  3 +-
 drivers/dma/mxs-dma.c                         |  3 +-
 drivers/media/platform/omap/omap_vout_vrfb.c  |  2 +-
 drivers/media/platform/pxa_camera.c           | 13 ++-
 drivers/rapidio/devices/rio_mport_cdev.c      |  3 +-
 include/linux/dmaengine.h                     | 55 +-----------
 18 files changed, 160 insertions(+), 133 deletions(-)