Public bug reported:

[Impact]
After suspend/resume, the internal display freezes and stops refreshing on
systems with SDC eDP panels using Panel Replay. The display content appears
frozen — typing or mouse movement shows no visual feedback. External
monitors continue to work normally.

The root cause is incorrect handling of Panel Replay Selective Update X
granularity DPCD registers (0xb2 and 0xb3). Per the DP specification,
0xffff means full-line granularity, but the driver did not handle this
special value, causing selective update to fail after suspend/resume.

Upstream bug: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/7284

[Fix]
Cherry-pick 5 upstream commits (v6.18 through v7.0-rc3):

- f861e54fb33b5 ("drm/i915/psr: Add panel granularity information into 
intel_connector")
- 90d8aad11f613 ("drm/i915/psr: Panel Replay SU cap dpcd read return value")
- 1cc854647450  ("drm/i915/psr: Use SU granularity information available in 
intel_connector")
- ace7dcc818137 ("drm/dp: Add definition for Panel Replay full-line 
granularity")
- a99cac460ddeb ("drm/i915/psr: Fix for Panel Replay X granularity DPCD 
register handling")

[Test Plan]
On a system with an SDC eDP panel supporting Panel Replay:

$ for i in $(seq 1 10); do sudo rtcwake -m mem -s 20; sleep 5; done

Without the patch: Internal display freezes after resume.
With the patch: Display refreshes normally after every resume.

[Where problems could occur]
Incorrect granularity handling could cause visual artifacts on panels with
non-0xffff granularity values. All patches are upstream and reviewed by
Intel display maintainers.

[Other Info]
SRU for OEM-6.17, questing, and resolute.

** Affects: hwe-next
     Importance: Undecided
     Assignee: AaronMa (mapengyu)
         Status: In Progress

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: In Progress

** Affects: linux-oem-6.17 (Ubuntu)
     Importance: Undecided
         Status: Invalid

** Affects: linux (Ubuntu Noble)
     Importance: Undecided
         Status: Won't Fix

** Affects: linux-oem-6.17 (Ubuntu Noble)
     Importance: Undecided
         Status: In Progress

** Affects: linux (Ubuntu Questing)
     Importance: Undecided
         Status: In Progress

** Affects: linux-oem-6.17 (Ubuntu Questing)
     Importance: Undecided
         Status: Invalid

** Affects: linux (Ubuntu Resolute)
     Importance: Undecided
         Status: In Progress

** Affects: linux-oem-6.17 (Ubuntu Resolute)
     Importance: Undecided
         Status: Invalid


** Tags: jira-sutton-4391 oem-priority sutton

** Tags added: jira-sutton-4391 oem-priority sutton

** Also affects: linux (Ubuntu Noble)
   Importance: Undecided
       Status: New

** Also affects: linux-oem-6.17 (Ubuntu Noble)
   Importance: Undecided
       Status: New

** Also affects: linux (Ubuntu Questing)
   Importance: Undecided
       Status: New

** Also affects: linux-oem-6.17 (Ubuntu Questing)
   Importance: Undecided
       Status: New

** Also affects: linux (Ubuntu Resolute)
   Importance: Undecided
       Status: New

** Also affects: linux-oem-6.17 (Ubuntu Resolute)
   Importance: Undecided
       Status: New

** Changed in: hwe-next
       Status: New => In Progress

** Changed in: hwe-next
     Assignee: (unassigned) => AaronMa (mapengyu)

** Changed in: linux (Ubuntu Noble)
       Status: New => In Progress

** Changed in: linux-oem-6.17 (Ubuntu Noble)
       Status: New => In Progress

** Changed in: linux (Ubuntu Questing)
       Status: New => In Progress

** Changed in: linux-oem-6.17 (Ubuntu Questing)
       Status: New => Invalid

** Changed in: linux (Ubuntu Resolute)
       Status: New => In Progress

** Changed in: linux-oem-6.17 (Ubuntu Resolute)
       Status: New => Invalid

** Changed in: linux (Ubuntu Noble)
       Status: In Progress => Won't Fix

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https://bugs.launchpad.net/bugs/2144637

Title:
  drm/i915/psr: Display freezes after suspend/resume with Panel Replay
  on SDC eDP panels

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