Commit Graph

4 Commits

Author SHA1 Message Date
Jay Cornwall
b7851f8c66 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>
(cherry picked from commit 4238888794)
Cc: stable@vger.kernel.org
2025-12-08 15:22:45 -05:00
Jay Cornwall
424648c383 drm/amdkfd: Fix instruction hazard in gfx12 trap handler
VALU instructions with SGPR source need wait states to avoid hazard
with SALU using different SGPR.

v2: Eliminate some hazards to reduce code explosion

Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7e0459d453)
Cc: stable@vger.kernel.org # 6.12.x
2025-03-18 16:28:34 -04:00
Lancelot SIX
d584198a6f drm/amdkfd: Ensure consistent barrier state saved in gfx12 trap handler
It is possible for some waves in a workgroup to finish their save
sequence before the group leader has had time to capture the workgroup
barrier state.  When this happens, having those waves exit do impact the
barrier state.  As a consequence, the state captured by the group leader
is invalid, and is eventually incorrectly restored.

This patch proposes to have all waves in a workgroup wait for each other
at the end of their save sequence (just before calling s_endpgm_saved).

Signed-off-by: Lancelot SIX <lancelot.six@amd.com>
Reviewed-by: Jay Cornwall <jay.cornwall@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # 6.12.x
2025-02-12 19:47:15 -05:00
Jay Cornwall
62498e797a drm/amdkfd: Move gfx12 trap handler to separate file
gfx12 derivatives will have substantially different trap handler
implementations from gfx10/gfx11. Add a separate source file for
gfx12+ and remove unneeded conditional code.

No functional change.

v2: Revert copyright date to 2018, minor comment fixes

Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
Cc: Jonathan Kim <jonathan.kim@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2025-01-09 16:02:56 -05:00