habanalabs: add wait-for-multi-CS uAPI

When user sends multiple CSs, waiting for each CS is not efficient
as it involves many user-kernel context switches.

In order to address this issue we add support to "wait on multiple CSs"
using a new uAPI which can wait on maximum of 32 CSs. The new uAPI is
defined using a new flag - WAIT_FOR_MULTI_CS - in the wait_for_cs IOCTL.

The input parameters for this uAPI will be:
@seq: user pointer to an array of up to 32 CS's sequence numbers.
@seq_array_len: length of sequence array.
@timeout_us: timeout for waiting for any CS.

The output paramateres for this API will be:
@status: multi CS ioctl completion status (dedicated status was added as
         well).
@flags: bitmap of output flags of the CS.
@cs_completion_map: bitmap for multi CS, if CS sequence that was placed
                    in index N in input seq array has completed- the N-th
		    bit in cs_completion_map will be 1, otherwise it will
		    be 0.
@timestamp_nsec: timestamp of the first completed CS

Signed-off-by: Ohad Sharabi <osharabi@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/misc/habanalabs/common/hw_queue.c b/drivers/misc/habanalabs/common/hw_queue.c
index 0afead229e97..f05a0dbd0990 100644
--- a/drivers/misc/habanalabs/common/hw_queue.c
+++ b/drivers/misc/habanalabs/common/hw_queue.c
@@ -603,6 +603,10 @@ int hl_hw_queue_schedule_cs(struct hl_cs *cs)
 		}
 
 		list_add_tail(&cs->staged_cs_node, &staged_cs->staged_cs_node);
+
+		/* update stream map of the first CS */
+		if (hdev->supports_wait_for_multi_cs)
+			staged_cs->fence->stream_map |= cs->fence->stream_map;
 	}
 
 	list_add_tail(&cs->mirror_node, &hdev->cs_mirror_list);