drm/i915/tgl: Tigerlake only has global MOCS registers

Until Icelake, each engine had its own set of 64 MOCS registers. In
order to simplify, Tigerlake moves to only 64 Global MOCS registers,
which are no longer part of the engine context. Since these registers
are now global, they also only need to be initialized once.

>From Gen12 onwards, MOCS must specify the target cache (3:2) and LRU
management (5:4) fields and cannot be programmed to 'use the value from
Private PAT', because these fields are no longer part of the PPAT. Also
cacheability control (1:0) field has changed, 00 no longer means 'use
controls from page table', but uncacheable (UC).

v2 (Lucas):
    - Move the changes to the fault registers to a separate commit - the
      old ones overlap with the range used by the new global MOCS
      (requested by Daniele)
v3 (Lucas):
    - Clarify comment about setting the unused entries to the same value
      of index 0, that is the invalid entry (requested by Daniele)
    - Move changes to DONE_REG and ERROR_GEN6 to a separate commit
      (requested by Daniele)

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Tomasz Lis <tomasz.lis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190730180407.5993-5-lucas.demarchi@intel.com

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_mocs.h b/drivers/gpu/drm/i915/gt/intel_mocs.h
index 8e20ca8bb34c..d5d3558caf4e 100644
--- a/drivers/gpu/drm/i915/gt/intel_mocs.h
+++ b/drivers/gpu/drm/i915/gt/intel_mocs.h
@@ -54,6 +54,7 @@ struct intel_engine_cs;
 struct intel_gt;
 
 void intel_mocs_init_l3cc_table(struct intel_gt *gt);
+void intel_mocs_init_global(struct intel_gt *gt);
 void intel_mocs_init_engine(struct intel_engine_cs *engine);
 
 int intel_mocs_emit(struct i915_request *rq);