History log of /linux-master/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c
Revision Date Author Comments
# 0eec708e 22-Nov-2023 Alan Previn <alan.previn.teres.alexis@intel.com>

drm/i915/pxp: Add drm_dbgs for critical PXP events.

Debugging PXP issues can't even begin without understanding precedding
sequence of important events. Add drm_dbg into the most important PXP
events.

v5 : - rebase.
v4 : - rebase.
v3 : - move gt_dbg to after mutex block in function
i915_gsc_proxy_component_bind. (Vivaik)
v2 : - remove __func__ since drm_dbg covers that (Jani).
- add timeout dbg of the restart from front-end (Alan).

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Vivaik Balasubrawmanian <vivaik.balasubrawmanian@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231122191523.58379-1-alan.previn.teres.alexis@intel.com


# f67986b0 08-Dec-2022 Alan Previn <alan.previn.teres.alexis@intel.com>

drm/i915/pxp: Promote pxp subsystem to top-level of i915

Starting with MTL, there will be two GT-tiles, a render and media
tile. PXP as a service for supporting workloads with protected
contexts and protected buffers can be subscribed by process
workloads on any tile. However, depending on the platform,
only one of the tiles is used for control events pertaining to PXP
operation (such as creating the arbitration session and session
tear-down).

PXP as a global feature is accessible via batch buffer instructions
on any engine/tile and the coherency across tiles is handled implicitly
by the HW. In fact, for the foreseeable future, we are expecting this
single-control-tile for the PXP subsystem.

In MTL, it's the standalone media tile (not the root tile) because
it contains the VDBOX and KCR engine (among the assets PXP relies on
for those events).

Looking at the current code design, each tile is represented by the
intel_gt structure while the intel_pxp structure currently hangs off the
intel_gt structure.

Keeping the intel_pxp structure within the intel_gt structure makes some
internal functionalities more straight forward but adds code complexity to
code readability and maintainibility to many external-to-pxp subsystems
which may need to pick the correct intel_gt structure. An example of this
would be the intel_pxp_is_active or intel_pxp_is_enabled functionality
which should be viewed as a global level inquiry, not a per-gt inquiry.

That said, this series promotes the intel_pxp structure into the
drm_i915_private structure making it a top-level subsystem and the PXP
subsystem will select the control gt internally and keep a pointer to
it for internal reference.

This promotion comes with two noteworthy changes:

1. Exported pxp functions that are called by external subsystems
(such as intel_pxp_enabled/active) will have to check implicitly
if i915->pxp is valid as that structure will not be allocated
for HW that doesn't support PXP.

2. Since GT is now considered a soft-dependency of PXP we are
ensuring that GT init happens before PXP init and vice versa
for fini. This causes a minor ordering change whereby we previously
called intel_pxp_suspend after intel_uc_suspend but now is before
i915_gem_suspend_late but the change is required for correct
dependency flows. Additionally, this re-order change doesn't
have any impact because at that point in either case, the top level
entry to i915 won't observe any PXP events (since the GPU was
quiesced during suspend_prepare). Also, any PXP event doesn't
really matter when we disable the PXP HW (global GT irqs are
already off anyway, so even if there was a bug that generated
spurious events we wouldn't see it and we would just clean it
up on resume which is okay since the default fallback action
for PXP would be to keep the sessions off at this suspend stage).

Changes from prior revs:
v11: - Reformat a comment (Tvrtko).
v10: - Change the code flow for intel_pxp_init to make it more
cleaner and readible with better comments explaining the
difference between full-PXP-feature vs the partial-teelink
inits depending on the platform. Additionally, only do
the pxp allocation when we are certain the subsystem is
needed. (Tvrtko).
v9: - Cosmetic cleanups in supported/enabled/active. (Daniele).
- Add comments for intel_pxp_init and pxp_get_ctrl_gt that
explain the functional flow for when PXP is not supported
but the backend-assets are needed for HuC authentication
(Daniele and Tvrtko).
- Fix two remaining functions that are accessible outside
PXP that need to be checking pxp ptrs before using them:
intel_pxp_irq_handler and intel_pxp_huc_load_and_auth
(Tvrtko and Daniele).
- User helper macro in pxp-debugfs (Tvrtko).
v8: - Remove pxp_to_gt macro (Daniele).
- Fix a bug in pxp_get_ctrl_gt for the case of MTL and we don't
support GSC-FW on it. (Daniele).
- Leave i915->pxp as NULL if we dont support PXP and in line
with that, do additional validity check on i915->pxp for
intel_pxp_is_supported/enabled/active (Daniele).
- Remove unncessary include header from intel_gt_debugfs.c
and check drm_minor i915->drm.primary (Daniele).
- Other cosmetics / minor issues / more comments on suspend
flow order change (Daniele).
v7: - Drop i915_dev_to_pxp and in intel_pxp_init use 'i915->pxp'
through out instead of local variable newpxp. (Rodrigo)
- In the case intel_pxp_fini is called during driver unload but
after i915 loading failed without pxp being allocated, check
i915->pxp before referencing it. (Alan)
v6: - Remove HAS_PXP macro and replace it with intel_pxp_is_supported
because : [1] introduction of 'ctrl_gt' means we correct this
for MTL's upcoming series now. [2] Also, this has little impact
globally as its only used by PXP-internal callers at the moment.
- Change intel_pxp_init/fini to take in i915 as its input to avoid
ptr-to-ptr in init/fini calls.(Jani).
- Remove the backpointer from pxp->i915 since we can use
pxp->ctrl_gt->i915 if we need it. (Rodrigo).
v5: - Switch from series to single patch (Rodrigo).
- change function name from pxp_get_kcr_owner_gt to
pxp_get_ctrl_gt.
- Fix CI BAT failure by removing redundant call to intel_pxp_fini
from driver-remove.
- NOTE: remaining open still persists on using ptr-to-ptr
and back-ptr.
v4: - Instead of maintaining intel_pxp as an intel_gt structure member
and creating a number of convoluted helpers that takes in i915 as
input and redirects to the correct intel_gt or takes any intel_gt
and internally replaces with the correct intel_gt, promote it to
be a top-level i915 structure.
v3: - Rename gt level helper functions to "intel_pxp_is_enabled/
supported/ active_on_gt" (Daniele)
- Upgrade _gt_supports_pxp to replace what was intel_gtpxp_is
supported as the new intel_pxp_is_supported_on_gt to check for
PXP feature support vs the tee support for huc authentication.
Fix pxp-debugfs-registration to use only the former to decide
support. (Daniele)
- Couple minor optimizations.
v2: - Avoid introduction of new device info or gt variables and use
existing checks / macros to differentiate the correct GT->PXP
control ownership (Daniele Ceraolo Spurio)
- Don't reuse the updated global-checkers for per-GT callers (such
as other files within PXP) to avoid unnecessary GT-reparsing,
expose a replacement helper like the prior ones. (Daniele).
v1: - Add one more patch to the series for the intel_pxp suspend/resume
for similar refactoring

References: https://patchwork.freedesktop.org/patch/msgid/20221202011407.4068371-1-alan.previn.teres.alexis@intel.com
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221208180542.998148-1-alan.previn.teres.alexis@intel.com


# 03d2c54d 06-Sep-2022 Matt Roper <matthew.d.roper@intel.com>

drm/i915/mtl: Use primary GT's irq lock for media GT

When we hook up interrupts (in the next patch), interrupts for the media
GT are still processed as part of the primary GT's interrupt flow. As
such, we should share the same IRQ lock with the primary GT. Let's
convert gt->irq_lock into a pointer and just point the media GT's
instance at the same lock the primary GT is using.

v2:
- Point media's gt->irq_lock at the primary GT lock properly. (Daniele)
- Fix jump target for intel_root_gt_init_early errors. (Daniele)

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220906234934.3655440-14-matthew.d.roper@intel.com
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>


# 0d6419e9 27-Jan-2022 Matt Roper <matthew.d.roper@intel.com>

drm/i915: Move GT registers to their own header file

This is a huge, chaotic mass of registers copied over as-is without any
real cleanup. We'll come back and organize these better, align on
consistent coding style, remove dead code, etc. in separate patches
later that will be easier to review.

v2:
- Add missing include in intel_pxp_irq.c
v3:
- Correct a few indentation errors (Lucas)
- Minor conflict resolution

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220127234334.4016964-6-matthew.d.roper@intel.com


# 0cfab4cb 24-Sep-2021 Huang, Sean Z <sean.z.huang@intel.com>

drm/i915/pxp: Enable PXP power management

During the power event S3+ sleep/resume, hardware will lose all the
encryption keys for every hardware session, even though the
session state might still be marked as alive after resume. Therefore,
we should consider the session as dead on suspend and invalidate all the
objects. The session will be automatically restarted on the first
protected submission on resume.

v2: runtime suspend also invalidates the keys
v3: fix return codes, simplify rpm ops (Chris), use the new worker func
v4: invalidate the objects on suspend, don't re-create the arb sesson on
resume (delayed to first submission).
v5: move irq changes back to irq patch (Rodrigo)
v6: drop invalidation in runtime suspend (Rodrigo)

Signed-off-by: Huang, Sean Z <sean.z.huang@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924191452.1539378-13-alan.previn.teres.alexis@intel.com


# 32271ecd 24-Sep-2021 Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>

drm/i915/pxp: start the arb session on demand

Now that we can handle destruction and re-creation of the arb session,
we can postpone the start of the session to the first submission that
requires it, to avoid keeping it running with no user.

v10: increase timeout when waiting in intel_pxp_start as firmware
session startup is slower right after boot.
v13: increase the same timeout by 50 milisec because previous timeout
was not enough to cover two lower level 100 milisec timeouts
in the session termination + creation steps.

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924191452.1539378-12-alan.previn.teres.alexis@intel.com


# 2ae09687 24-Sep-2021 Huang, Sean Z <sean.z.huang@intel.com>

drm/i915/pxp: Implement PXP irq handler

The HW will generate a teardown interrupt when session termination is
required, which requires i915 to submit a terminating batch. Once the HW
is done with the termination it will generate another interrupt, at
which point it is safe to re-create the session.

Since the termination and re-creation flow is something we want to
trigger from the driver as well, use a common work function that can be
called both from the irq handler and from the driver set-up flows, which
has the addded benefit of allowing us to skip any extra locks because
the work itself serializes the operations.

v2: use struct completion instead of bool (Chris)
v3: drop locks, clean up functions and improve comments (Chris),
move to common work function.
v4: improve comments, simplify wait logic (Rodrigo)
v5: unconditionally set interrupts, rename state_attacked var (Rodrigo)
v10: remove inclusion of intel_gt_types.h from intel_pxp.h (Jani)

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Signed-off-by: Huang, Sean Z <sean.z.huang@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924191452.1539378-10-alan.previn.teres.alexis@intel.com