During early initialization, in the xe_guc_min_load_for_hwconfig()
function, we are successfully enabling CTB communication, but it
will only allow us to send non-blocking H2G messages, as due to
not yet enabled IRQs, including G2H IRQs, we will not notice any
new G2H message sent by the GuC, including replies to our blocking
H2G request messages. And those successful replies are mandatory
for the VF drivers to continue normal operations.
As attempt to workaround this driver initialization ordering issue,
introduce special safe-mode CTB worker, that will periodically
trigger G2H processing, like original IRQ handler, in case no
MSI/MSIX IRQs were enabled on the driver yet. Once we detect that
IRQ were enabled, we will stop this worker.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240606130639.1504-3-michal.wajdeczko@intel.com
The flags stored in the BO grew over time without following
much a naming pattern. First of all, get rid of the _BIT suffix that was
banned from everywhere else due to the guideline in
drivers/gpu/drm/i915/i915_reg.h that xe kind of follows:
Define bits using ``REG_BIT(N)``. Do **not** add ``_BIT`` suffix to the name.
Here the flags aren't for a register, but it's good practice to keep it
consistent.
Second divergence on names is the use or not of "CREATE". This is
because most of the flags are passed to xe_bo_create*() family of
functions, changing its behavior. However, since the flags are also
stored in the bo itself and checked elsewhere in the code, it seems
better to just omit the CREATE part.
With those 2 guidelines, all the flags are given the form
XE_BO_FLAG_<FLAG_NAME> with the following commands:
git grep -le "XE_BO_" -- drivers/gpu/drm/xe | xargs sed -i \
-e "s/XE_BO_\([_A-Z0-9]*\)_BIT/XE_BO_\1/g" \
-e 's/XE_BO_CREATE_/XE_BO_FLAG_/g'
git grep -le "XE_BO_" -- drivers/gpu/drm/xe | xargs sed -i -r \
-e 's/XE_BO_(DEFER_BACKING|SCANOUT|FIXED_PLACEMENT|PAGETABLE|NEEDS_CPU_ACCESS|NEEDS_UC|INTERNAL_TEST|INTERNAL_64K|GGTT_INVALIDATE)/XE_BO_FLAG_\1/g'
And then the defines in drivers/gpu/drm/xe/xe_bo.h are adjusted to
follow the coding style.
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240322142702.186529-3-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
GuC will use VF_STATE_NOTIFY events to notify the PF about changes
of the VF state, in particular when a VF FLR was requested. Add
very minimal support for such events to avoid reporting errors due
to unexpected G2H. We will improve handling of these messages later.
While around also add few basic functions to control the VF state
(pause, resume, stop) as we will also exercise them soon.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240326191518.363-3-michal.wajdeczko@intel.com
The Guc CT has more than enabled / disables states rather it has 4. The
4 states are not initialized, disabled, stopped, and enabled. Change the
code to reflect this. These states will enable proper return codes from
functions and therefore enable proper error messages.
v2:
- s/XE_GUC_CT_STATE_DROP_MESSAGES/XE_GUC_CT_STATE_STOPPED (Michal)
- Add assert for CT being initialized (Michal)
- Fix kernel for CT state enum (Michal)
v3:
- Kernel doc (Michal)
- s/reiecved/received (Michal)
- assert CT state not initialized in xe_guc_ct_init (Michal)
- add argument xe_guc_ct_set_state to clear g2h (Michal)
v4:
- Drop clear_outstanding_g2h argument (Michal)
v5:
- Move xa_destroy outside of fast lock (CI)
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Tejas Upadhyay <tejas.upadhyay@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240122210156.1517444-2-matthew.brost@intel.com
Not all CTB responses from the GuC are fixed size and we need to
pass response length to the caller, if there was a response_buffer.
Easiest solution is to return it as positive value from all
xe_guc_ct_send_recv() functions. The CTB response length is always
between 1 and 254 (ie. GUC_HXG_MSG_MIN_LEN and GUC_CTB_MAX_DWORDS
- GUC_HXG_MSG_MIN_LEN).
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20240111152724.497-1-michal.wajdeczko@intel.com
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
We're currently sending non-blocking H2G messages using the EVENT type,
which suppresses all CTB protocol replies from the GuC, including the
failure cases. This might cause errors to slip through and manifest as
unexpected behavior (e.g. a context state might not be what the driver
thinks it is because the state change command was silently rejected by
the GuC). To avoid this kind of problems, we can use the FAST_REQUEST
type instead, which suppresses the reply only on success; this way we
still get the advantage of not having to wait for an ack from the GuC
(i.e. the H2G is still non-blocking) while still detecting errors.
Since we can't escalate to the caller when a non-blocking message
fails, we need to escalate to GT reset instead.
Note that FAST_REQUEST failures are NOT expected and are usually a sign
that the H2G was either malformed or requested an illegal operation.
v2: assign fence values to FAST_REQUEST messages, fix abi doc, use xe_gt
printers (Michal).
v3: fix doc alignment, fix and improve prints (Michal)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com> #v2
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
A helper for managed BO allocations makes it possible to remove specific
"fini" actions and will simplify the following patches adding ability to
execute a release action for specific BO directly.
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This variable holds full length of the message, including header
length so it should be checked against GUC_CTB_MSG_MAX_LEN.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The XE_WARN_ON macro maps to WARN_ON which is not justified
in many cases where only a simple debug check is needed.
Replace the use of the XE_WARN_ON macro with the new xe_assert
macros which relies on drm_*. This takes a struct drm_device
argument, which is one of the main changes in this commit. The
other main change is that the condition is reversed, as with
XE_WARN_ON a message is displayed if the condition is true,
whereas with xe_assert it is if the condition is false.
v2:
- Rebase
- Keep WARN splats in xe_wopcm.c (Matt Roper)
v3:
- Rebase
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Use the generic drm_warn instead of the driver-specific XE_WARN_ON
in cases where XE_WARN_ON is used to unconditionally print a debug
message.
v2: Rebase
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Replace calls to XE_BUG_ON() with calls XE_WARN_ON() which in turn calls
WARN() instead of BUG(). BUG() crashes the kernel and should only be
used when it is absolutely unavoidable in case of catastrophic and
unrecoverable failures, which is not the case here.
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
XE_GUC_CT_SELFTEST enabled a debugfs entry to which ran a very simple
selftest ensuring the GuC CT code worked. This was added before the
kunit framework was available and before submissions were working too.
This test isn't worth porting over to the kunit frame as if the GuC CT
didn't work, literally almost nothing would work so just remove this.
Suggested-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
It looks like there is at least one race here, given that the
pm_runtime_suspended() check looks to return false if we are in the
process of suspending the device (RPM_SUSPENDING vs RPM_SUSPENDED). We
later also do xe_pm_runtime_get_if_active(), but since the device is
suspending or has now suspended, this doesn't do anything either.
Following from this we can potentially return from
xe_device_mem_access_get() with the device suspended or about to be,
leading to broken behaviour.
Attempt to fix this by always grabbing the runtime ref when our internal
ref transitions from 0 -> 1. The hard part is then dealing with the
runtime_pm callbacks also calling xe_device_mem_access_get() and
deadlocking, which the pm_runtime_suspended() check prevented.
v2:
- ct->lock looks to be primed with fs_reclaim, so holding that and then
allocating memory will cause lockdep to complain. Now that we
unconditionally grab the mem_access.lock around mem_access_{get,put}, we
need to change the ordering wrt to grabbing the ct->lock, since some of
the runtime_pm routines can allocate memory (or at least that's what
lockdep seems to suggest). Hopefully not a big deal. It might be that
there were already issues with this, just that the atomics where
"hiding" the potential issues.
v3:
- Use Thomas Hellström' idea with tracking the active task that is
executing in the resume or suspend callback, in order to avoid
recursive resume/suspend calls deadlocking on itself.
- Split the ct->lock change.
v4:
- Add smb_mb() around accessing the pm_callback_task for extra safety.
(Thomas Hellström)
v5:
- Clarify the kernel-doc for the mem_access.lock, given that it is quite
strange in what it protects (data vs code). The real motivation is to
aid lockdep. (Rodrigo Vivi)
v6:
- Split out the lock change. We still want this as a lockdep aid but
only for the xe_device_mem_access_get() path. Sticking a lock on the
put() looks be a no-go, also the runtime_put() there is always async.
- Now that the lock is gone move to atomics and rely on the pm code
serialising multiple callers on the 0 -> 1 transition.
- g2h_worker_func() looks to be the next issue, given that
suspend-resume callbacks are using CT, so try to handle that.
v7:
- Add xe_device_mem_access_get_if_ongoing(), and use it in
g2h_worker_func().
v8 (Anshuman):
- Just always grab the rpm, instead of just on the 0 -> 1 transition,
which is a lot clearer and simplifies the code quite a bit.
v9:
- Make sure we also adjust the CT fast-path with if-active.
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/258
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Anshuman Gupta <anshuman.gupta@intel.com>
Acked-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reduce the number of warnings reported by checkpatch.pl from 118 to 48 by
addressing those warnings types:
LEADING_SPACE
LINE_SPACING
BRACES
TRAILING_SEMICOLON
CONSTANT_COMPARISON
BLOCK_COMMENT_STYLE
RETURN_VOID
ONE_SEMICOLON
SUSPECT_CODE_INDENT
LINE_CONTINUATIONS
UNNECESSARY_ELSE
UNSPECIFIED_INT
UNNECESSARY_INT
MISORDERED_TYPE
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
In various test cases that put the system under a heavy load, we can
sometimes see errors with missed TLB invalidations. In such cases we see
the interrupt arrive for the invalidation from the GuC, however the
actual processing of the completion is pushed onto a workqueue and
handled with all the other CT stuff, which might take longer than
expected. Since we expect TLB invalidations to complete within a
reasonable amount of time (at most ~250ms), and they do seem pretty
critical, allow handling directly from the CT fast-path.
v2 (José):
- Actually use the correct spinlock/unlock_irq, since pending_lock is
grabbed from IRQ.
v3:
- Don't publish the TLB fence on the list until after we fully
initialize it and successfully do the CT send. The list is now only
protected by the spin_lock pending_lock and we can't hold that
across the entire TLB send operation.
v4 (Matt Brost):
- Be careful with racing against fast CT path writing the seqno,
before we have actually published the fence.
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/297
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/320
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/449
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
