When running the GuC the GPU can't be considered idle if the GuC still
has contexts pinned. As such, a call has been added in
intel_gt_wait_for_idle to idle the UC and in turn the GuC by waiting for
the number of unpinned contexts to go to zero.
v2: rtimeout -> remaining_timeout
v3: Drop unnecessary includes, guc_submission_busy_loop ->
guc_submission_send_busy_loop, drop negatie timeout trick, move a
refactor of guc_context_unpin to earlier path (John H)
v4: Add stddef.h back into intel_gt_requests.h, sort circuit idle
function if not in GuC submission mode
Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721215101.139794-16-matthew.brost@intel.com
CTB writes are now in the path of command submission and should be
optimized for performance. Rather than reading CTB descriptor values
(e.g. head, tail) which could result in accesses across the PCIe bus,
store shadow local copies and only read/write the descriptor values when
absolutely necessary. Also store the current space in the each channel
locally.
v2:
(Michal)
- Add additional sanity checks for head / tail pointers
- Use GUC_CTB_HDR_LEN rather than magic 1
v3:
(Michal / John H)
- Drop redundant check of head value
v4:
(John H)
- Drop redundant checks of tail / head values
v5:
(Michal)
- Address more nits
v6:
(Michal)
- Add GEM_BUG_ON sanity check on ctb->space
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210708162055.129996-7-matthew.brost@intel.com
Add non blocking CTB send function, intel_guc_send_nb. GuC submission
will send CTBs in the critical path and does not need to wait for these
CTBs to complete before moving on, hence the need for this new function.
The non-blocking CTB now must have a flow control mechanism to ensure
the buffer isn't overrun. A lazy spin wait is used as we believe the
flow control condition should be rare with a properly sized buffer.
The function, intel_guc_send_nb, is exported in this patch but unused.
Several patches later in the series make use of this function.
v2:
(Michal)
- Use define for H2G room calculations
- Move INTEL_GUC_SEND_NB define
(Daniel Vetter)
- Use msleep_interruptible rather than cond_resched
v3:
(Michal)
- Move includes to following patch
- s/INTEL_GUC_SEND_NB/INTEL_GUC_CT_SEND_NB/g
v4:
(John H)
- Update comment, add type local variable
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210708162055.129996-5-matthew.brost@intel.com
The GuC supports having multiple CT buffer pairs and we designed our
implementation with that in mind. However, the different channels are not
processed in parallel within the GuC, so there is very little advantage
in having multiple channels (independent locks?), compared to the
drawbacks (one channel can starve the other if messages keep being
submitted to it). Given this, it is unlikely we'll ever add a second
channel and therefore we can simplify our code by removing the
flexibility.
v2: split substructure grouping to separate patch, improve docs (Michal)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191217012316.13271-3-daniele.ceraolospurio@intel.com
The only difference from the GuC POV between guc_communication_stop and
guc_communication_disable is that the former can be called after GuC
has been reset. Instead of having two separate paths, we can just skip
the call into GuC in the disabling path and re-use that.
Note that by using the disable() path instead of the stop() one there
are two additional changes in SW side for the stop path:
- interrupts are now disabled before disabling the CT, which is ok
because we do not want interrupts with CT disabled;
- guc_get_mmio_msg() is called in the stop case as well, which is ok
because if there are errors before the reset we do want to record
them.
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191217012316.13271-1-daniele.ceraolospurio@intel.com
