[PATCH v4 0/4] drm/xe/sysctrl: Add System Controller debugfs

["Anoop, Vijay" <anoop.c.vijay@intel.com>]

From: Anoop Vijay <anoop.c.vijay@intel.com>

This series adds debugfs-based test interfaces for the System
Controller (sysctrl) mailbox, to aid validation of firmware
communication and RAS error handling without requiring userspace
tooling.

Key features introduced:
- Debugfs infrastructure for sysctrl (types, registration hook)
- Loopback test entry exercising the mailbox send/receive path via
  the Core group's inverted loopback command (0xFF/0x03)
- RAS error injection entry exercising the Diag group's
  RAS_ERR_INJECT command (0x02/0x7E), gated on the diag application
  having completed firmware boot/init
- Generic mailbox passthrough entry for any group/command not
  covered by a dedicated entry

Design question from v3 review:
The review suggested hiding the ras_error_inject debugfs file until 
the diag firmware is ready. Since there is no firmware-ready event 
to trigger registration, this revision keeps the file visible under
sc/ but blocks access. Both read and write operations return -ENODEV
until the diag firmware reports ready.

v4 (Rodrigo, Anshuman):
- Added lore links to the parent application-status series
- Squashed debugfs infrastructure and loopback support into a single commit
- Gated ras_error_inject on diag firmware readiness in .open()
- Added a generic mailbox debugfs entry

v3:
- Fix RAS error injection command ID to 0x7E
- Add xe_pm_runtime guard for mailbox commands
- Rename error injection command to avoid fwctl command ID collision
- Reject writes until the diag firmware is ready


Anoop Vijay (4):
  drm/xe/sysctrl: Add System Controller get application status
  drm/xe/sysctrl: Add sysctrl debugfs infrastructure and loopback test
    interface
  drm/xe/sysctrl: Add RAS error injection debugfs interface
  drm/xe/sysctrl: Add generic mailbox passthrough debugfs entry

 drivers/gpu/drm/xe/Makefile                   |   1 +
 drivers/gpu/drm/xe/xe_debugfs.c               |   5 +
 drivers/gpu/drm/xe/xe_sysctrl.c               |  82 ++++
 drivers/gpu/drm/xe/xe_sysctrl.h               |   2 +
 drivers/gpu/drm/xe/xe_sysctrl_debugfs.c       | 405 ++++++++++++++++++
 drivers/gpu/drm/xe/xe_sysctrl_debugfs.h       |  14 +
 drivers/gpu/drm/xe/xe_sysctrl_mailbox_types.h |  98 +++++
 drivers/gpu/drm/xe/xe_sysctrl_types.h         |  41 ++
 8 files changed, 648 insertions(+)
 create mode 100644 drivers/gpu/drm/xe/xe_sysctrl_debugfs.c
 create mode 100644 drivers/gpu/drm/xe/xe_sysctrl_debugfs.h

-- 
2.43.0