[PATCH v3 0/2] Add prefetch fault support for Xe3p

[Varun Gupta <varun.gupta@intel.com>]

Xe3p hardware prefetches memory ranges and notifies software via an
additional bit (bit 11) in the page fault descriptor that the fault
was caused by prefetch.

Patch 1 adds a dedicated stats counter to track invalid prefetch
pagefaults separately from regular faults.

Patch 2 implements the prefetch support by extracting the prefetch bit
from the fault descriptor and echoing it in the response (bit 6) only
when handling fails. This prevents CAT errors for prefetch faults.
Stats are incremented for prefetch errors without verbose logging to
avoid log spam. The prefetch bit value is included in error messages
to distinguish prefetch faults from regular faults.

Based on original patches by Brian Welty and Priyanka Dandamudi.

v3:
 - Split stats counter into separate patch (Matt Brost)
 - Drop xe_guc_pagefault_types.h rename patch (Matt Brost)
 - Move prefetch check to caller of xe_pagefault_print (Matt Brost)
 - Rename XE3P_PFD_PREFETCH/PFR_PREFETCH to remove XE3P_ prefix,
   add comments about Xe3+ platform support (Matt Brost)
 - Rename PREFETCH_PAGEFAULT_COUNT to INVALID_PREFETCH_PAGEFAULT_COUNT
   for clarity (Matt Brost)
 - Include prefetch bit value in error message (Matt Brost)

v2:
 - Initial implementation combining all changes

Varun Gupta (2):
  drm/xe: Add counter for invalid prefetch pagefaults
  drm/xe: Add prefetch fault support for Xe3p

 drivers/gpu/drm/xe/xe_gt_stats.c        |  1 +
 drivers/gpu/drm/xe/xe_gt_stats_types.h  |  1 +
 drivers/gpu/drm/xe/xe_guc_fwif.h        |  5 +++--
 drivers/gpu/drm/xe/xe_guc_pagefault.c   |  2 ++
 drivers/gpu/drm/xe/xe_pagefault.c       | 16 +++++++++++++---
 drivers/gpu/drm/xe/xe_pagefault_types.h |  8 +++++++-
 6 files changed, 27 insertions(+), 6 deletions(-)

-- 
2.43.0