Hi Veera,
On Wed, 20 Jan 2021 at 02:00, John Stultz john.stultz@linaro.org wrote:
On Fri, Jan 15, 2021 at 4:31 PM Veera Sundaram Sankaran veeras@codeaurora.org wrote:
Some drivers have hardware capability to get the precise HW timestamp of certain events based on which the fences are triggered. The delta between the event HW timestamp & current HW reference timestamp can be used to calculate the timestamp in kernel's CLOCK_MONOTONIC time domain. This allows it to set accurate timestamp factoring out any software and IRQ latencies. Add a timestamp variant of fence signal function, dma_fence_signal_timestamp to allow drivers to update the precise timestamp for fences.
Thank you for the patches!
Daniel, Christian, Gustavo: if there are no objections, I will queue up this series via drm-misc-next.
Changes in v2:
- Add a new fence signal variant instead of modifying fence struct
Changes in v3:
- Add timestamp domain information to commit-text and
dma_fence_signal_timestamp documentation
Signed-off-by: Veera Sundaram Sankaran veeras@codeaurora.org
drivers/dma-buf/dma-fence.c | 70 ++++++++++++++++++++++++++++++++++++++++----- include/linux/dma-fence.h | 3 ++ 2 files changed, 66 insertions(+), 7 deletions(-)
Thanks for respinning this!
Reviewed-by: John Stultz john.stultz@linaro.org
-john
Best, Sumit.