6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthew Brost <matthew.brost@xxxxxxxxx>
commit b1231ff7ea0689d04040a44864c265bc11612fa8 upstream.
RING_CMD_CCTL read index should be UC on iGPU parts due to L3 caching
structure. Having this as WB blocks ULLS from being enabled. Change to
UC to unblock ULLS on iGPU.
v2:
- Drop internal communications commnet, bspec is updated
Cc: Balasubramani Vivekanandan <balasubramani.vivekanandan@xxxxxxxxx>
Cc: Michal Mrozek <michal.mrozek@xxxxxxxxx>
Cc: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx>
Cc: José Roberto de Souza <jose.souza@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 328e089bfb37 ("drm/xe: Leverage ComputeCS read L3 caching")
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
Acked-by: Michal Mrozek <michal.mrozek@xxxxxxxxx>
Reviewed-by: Stuart Summers <stuart.summers@xxxxxxxxx>
Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20250114002507.114087-1-matthew.brost@xxxxxxxxx
(cherry picked from commit 758debf35b9cda5450e40996991a6e4b222899bd)
Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/xe/xe_hw_engine.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/xe/xe_hw_engine.c
+++ b/drivers/gpu/drm/xe/xe_hw_engine.c
@@ -417,7 +417,7 @@ hw_engine_setup_default_state(struct xe_
* Bspec: 72161
*/
const u8 mocs_write_idx = gt->mocs.uc_index;
- const u8 mocs_read_idx = hwe->class == XE_ENGINE_CLASS_COMPUTE &&
+ const u8 mocs_read_idx = hwe->class == XE_ENGINE_CLASS_COMPUTE && IS_DGFX(xe) &&
(GRAPHICS_VER(xe) >= 20 || xe->info.platform == XE_PVC) ?
gt->mocs.wb_index : gt->mocs.uc_index;
u32 ring_cmd_cctl_val = REG_FIELD_PREP(CMD_CCTL_WRITE_OVERRIDE_MASK, mocs_write_idx) |
