drm/amdkfd: Trap handler support for expert scheduling mode

The trap may be entered with dependency checking disabled.
Wait for dependency counters and save/restore scheduling mode.

v2:

Use ttmp1 instead of ttmp11. ttmp11 is not zero-initialized.
While the trap handler does zero this field before use, a user-mode
second-level trap handler could not rely on this being zero when
using an older kernel mode driver.

v3:

Use ttmp11 primarily but copy to ttmp1 before jumping to the
second level trap handler. ttmp1 is inspectable by a debugger.
Unexpected bits in the unused space may regress existing software.

Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Jay Cornwall 2025-11-14 14:32:42 -06:00 • committed by Alex Deucher
commit 4238888794
2 changed files with 73 additions and 26 deletions