Re: [PATCH v5 0/9] Introduce Xe PCIe FLR

[Matthew Brost <matthew.brost@intel.com>]

On Thu, Apr 16, 2026 at 08:19:47AM +0200, Raag Jadav wrote:
> On Wed, Apr 15, 2026 at 08:47:50AM -0700, Daniele Ceraolo Spurio wrote:
> > On 4/6/2026 7:07 AM, Raag Jadav wrote:
> > > Here's my humble attempt at introducing PCIe Function Level Reset (FLR)
> > > support in xe driver. This is ofcourse a half baked implementation and
> > > only limited to re-initializing GT. This needs to be extended for a lot
> > > of different components which I've skipped here for my lack of competence,
> > > so feel free to join in and support them.
> > 
> > I'm jumping in to review a bit late, sorry for that.
> 
> Thank you.
> 
> > I think we need a comment (both here and in code) to detail exactly what we
> > expect to happen around the FLR (or let me know if it's already somewhere
> > because I couldn't spot it). Which objects are expected to survive, which
> > ones do we need to recover or discard (and why)?
> > I'll sprinkle a few question in the relevant patches.
> 
> Yeah, there's not much of internal documentation from software POV either.
> I'm just making this up as I go along.
> 

Completely valid design flow...

But +1 to Daniele's suggestion - once we land on a design, let's write it
down somewhere in comments / kernel doc.

Matt 

> Raag
> 
> > > PS: All xe_exec_basic tests and clpeak run smoothly after FLR. Give it
> > > a spin and let me know if any regressions.
> > > 
> > > Trigger it with:
> > > 
> > > $ echo 1 > /sys/bus/pci/devices/<BDF>/reset
> > > 
> > > v2: Re-initialize migrate context (Matthew Brost)
> > >      Add kernel doc (Matthew Brost)
> > >      Spell out Function Level Reset (Jani)
> > > 
> > > v3: Cancel in-flight jobs before FLR
> > > 
> > > v4: Teardown exec queues instead of mangling scheduler pending list (Matthew Brost)
> > > 
> > > v5: Re-initialize kernel queues through submission backend (Matthew Brost)
> > >      Prevent PM ref leak for wedged device (Matthew Brost)
> > > 
> > > Raag Jadav (9):
> > >    drm/xe/uc_fw: Allow re-initializing firmware
> > >    drm/xe/guc_submit: Introduce guc_exec_queue_reinit()
> > >    drm/xe/gt: Introduce FLR helpers
> > >    drm/xe/irq: Introduce xe_irq_disable()
> > >    drm/xe: Introduce xe_device_assert_lmem_ready()
> > >    drm/xe/bo_evict: Introduce xe_bo_restore_map()
> > >    drm/xe/exec_queue: Introduce xe_exec_queue_reinit()
> > >    drm/xe/migrate: Introduce xe_migrate_reinit()
> > >    drm/xe/pci: Introduce PCIe FLR
> > > 
> > >   drivers/gpu/drm/xe/Makefile              |   1 +
> > >   drivers/gpu/drm/xe/xe_bo_evict.c         |  51 ++++++--
> > >   drivers/gpu/drm/xe/xe_bo_evict.h         |   2 +
> > >   drivers/gpu/drm/xe/xe_device.c           |  10 +-
> > >   drivers/gpu/drm/xe/xe_device.h           |   1 +
> > >   drivers/gpu/drm/xe/xe_device_types.h     |   3 +
> > >   drivers/gpu/drm/xe/xe_exec_queue.c       |  37 +++++-
> > >   drivers/gpu/drm/xe/xe_exec_queue.h       |   1 +
> > >   drivers/gpu/drm/xe/xe_exec_queue_types.h |   2 +
> > >   drivers/gpu/drm/xe/xe_gpu_scheduler.h    |   5 +
> > >   drivers/gpu/drm/xe/xe_gsc.c              |  14 ++
> > >   drivers/gpu/drm/xe/xe_gsc.h              |   1 +
> > >   drivers/gpu/drm/xe/xe_gt.c               |  47 +++++++
> > >   drivers/gpu/drm/xe/xe_gt.h               |   2 +
> > >   drivers/gpu/drm/xe/xe_gt_types.h         |   9 ++
> > >   drivers/gpu/drm/xe/xe_guc.c              |  29 ++++
> > >   drivers/gpu/drm/xe/xe_guc.h              |   2 +
> > >   drivers/gpu/drm/xe/xe_guc_submit.c       |  11 ++
> > >   drivers/gpu/drm/xe/xe_huc.c              |  14 ++
> > >   drivers/gpu/drm/xe/xe_huc.h              |   1 +
> > >   drivers/gpu/drm/xe/xe_irq.c              |  13 +-
> > >   drivers/gpu/drm/xe/xe_irq.h              |   1 +
> > >   drivers/gpu/drm/xe/xe_lrc.c              |  17 +++
> > >   drivers/gpu/drm/xe/xe_lrc.h              |   2 +
> > >   drivers/gpu/drm/xe/xe_migrate.c          |  12 ++
> > >   drivers/gpu/drm/xe/xe_migrate.h          |   1 +
> > >   drivers/gpu/drm/xe/xe_pci.c              |   1 +
> > >   drivers/gpu/drm/xe/xe_pci.h              |   2 +
> > >   drivers/gpu/drm/xe/xe_pci_err.c          | 160 +++++++++++++++++++++++
> > >   drivers/gpu/drm/xe/xe_uc.c               |  37 ++++++
> > >   drivers/gpu/drm/xe/xe_uc.h               |   2 +
> > >   drivers/gpu/drm/xe/xe_uc_fw.c            |  39 +++++-
> > >   drivers/gpu/drm/xe/xe_uc_fw.h            |   1 +
> > >   33 files changed, 510 insertions(+), 21 deletions(-)
> > >   create mode 100644 drivers/gpu/drm/xe/xe_pci_err.c
> > > 
> >