On Gen8+ this register is not priviledged and we want to use it in
Mesa to implement a feature required by GPA called Null Hardware. The
idea is to have the command parser turn 3DPRIMITIVE/GPGPU_WALKER into
NOOPs.

This patch just whitelists the bits that we need and that are
currently not used by the kernel.

v2: Bump the command parser revision (Chris)

v3: Whitelist TEXTURE_PALETTE_LOAD_INSTRUCTION_DISABLE (Chris)

Signed-off-by: Lionel Landwerlin <lionel.g.landwer...@intel.com>
---
 drivers/gpu/drm/i915/i915_cmd_parser.c | 13 ++++++++++++-
 drivers/gpu/drm/i915/i915_reg.h        |  5 +++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c 
b/drivers/gpu/drm/i915/i915_cmd_parser.c
index 95478db9998b..ecf2aede04ed 100644
--- a/drivers/gpu/drm/i915/i915_cmd_parser.c
+++ b/drivers/gpu/drm/i915/i915_cmd_parser.c
@@ -534,6 +534,16 @@ struct drm_i915_reg_descriptor {
        { .addr = _reg ## _UDW(idx) }
 
 static const struct drm_i915_reg_descriptor gen7_render_regs[] = {
+       REG32(INSTPM,
+             .mask = ~((INSTPM_TEXTURE_PALETTE_LOAD_INSTRUCTION_DISABLE |
+                        INSTPM_3D_STATE_INSTRUCTION_DISABLE |
+                        INSTPM_3D_RENDERING_INSTRUCTION_DISABLE |
+                        INSTPM_MEDIA_INSTRUCTION_DISABLE) << 16 |
+                       (INSTPM_TEXTURE_PALETTE_LOAD_INSTRUCTION_DISABLE |
+                        INSTPM_3D_STATE_INSTRUCTION_DISABLE |
+                        INSTPM_3D_RENDERING_INSTRUCTION_DISABLE |
+                        INSTPM_MEDIA_INSTRUCTION_DISABLE)),
+             .value = 0),
        REG64(GPGPU_THREADS_DISPATCHED),
        REG64(HS_INVOCATION_COUNT),
        REG64(DS_INVOCATION_COUNT),
@@ -1382,6 +1392,7 @@ int i915_cmd_parser_get_version(struct drm_i915_private 
*dev_priv)
         *    the parser enabled.
         * 9. Don't whitelist or handle oacontrol specially, as ownership
         *    for oacontrol state is moving to i915-perf.
+        * 10. Whitelist bits of INSTPM on Ivybridge & Haswell.
         */
-       return 9;
+       return 10;
 }
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 196a0eb79272..ebfc9cdc5378 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2530,7 +2530,12 @@ enum i915_power_well_id {
                                        be delivered when out of C3. */
 #define   INSTPM_FORCE_ORDERING                                (1<<7) /* GEN6+ 
*/
 #define   INSTPM_TLB_INVALIDATE        (1<<9)
+#define   INSTPM_CONSTANT_BUFFER_ADDRESS_OFFSET_DISABLE   (1 << 6) /* GEN6+ */
 #define   INSTPM_SYNC_FLUSH    (1<<5)
+#define   INSTPM_MEDIA_INSTRUCTION_DISABLE                (1 << 3) /* GEN6+ */
+#define   INSTPM_3D_RENDERING_INSTRUCTION_DISABLE         (1 << 2) /* GEN6+ */
+#define   INSTPM_3D_STATE_INSTRUCTION_DISABLE             (1 << 1) /* GEN6+ */
+#define   INSTPM_TEXTURE_PALETTE_LOAD_INSTRUCTION_DISABLE (1 << 0) /* GEN6+ */
 #define ACTHD          _MMIO(0x20c8)
 #define MEM_MODE       _MMIO(0x20cc)
 #define   MEM_DISPLAY_B_TRICKLE_FEED_DISABLE (1<<3) /* 830 only */
-- 
2.17.0

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