drm/xe/mocs: LNCF MOCS settings only need to be restored on pre-Xe_HP

Browse source

Reprogramming the LNCF MOCS registers on render domain reset is not
intended to be regular driver programming, but rather the implementation
of a specific workaround (Wa_1607983814).  This workaround no longer
applies on Xe_HP any beyond, so we can expect that these registers, like
the rest of the LNCF/LBCF registers, will maintain their values through
all engine resets.  We should only add these registers to the GuC's
save/restore list on platforms that need the workaround.

Furthermore, xe_mocs_init_engine() appears to be another attempt to
satisfy this same workaround.  This is unnecessary on the Xe driver
since even on platforms where the workaround is necessary, all
single-engine resets are initiated by the GuC and thus the GuC will take
care of saving/restoring these registers.  The only host-initiated
resets we have in Xe are full GT resets which will already
(re)initialize these registers as part of the regular xe_mocs_init()
flow.

v2:
 - Add needs_wa_1607983814() so that calculate_regset_size() doesn't
   overallocate regset space when the workaround isn't needed.  (Lucas)
 - On platforms affected by Wa_1607983814, only add the LNCF MOCS
   registers to the render engine's GuC save/restore list; resets of
   other engines don't need to save/restore these.

Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

...

This commit is contained in:

Matt Roper 2023-02-23 10:57:39 -08:00 • committed by Rodrigo Vivi

parent ee17e7f34a

commit f659ac1564

5 changed files with 17 additions and 20 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

drivers/gpu/drm/xe/xe_execlist.c

View file

20

drivers/gpu/drm/xe/xe_guc_ads.c

View file

1

drivers/gpu/drm/xe/xe_guc_submit.c

View file

13

drivers/gpu/drm/xe/xe_mocs.c

View file

1

drivers/gpu/drm/xe/xe_mocs.h

View file