[Intel-gfx] [PATCH] drm/i915/tgl: WaEnablePreemptionGranularityControlByUMD

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Certain workloads need the ability to disable preemption completely so
allow them to do that by whitelisting GEN8_CS_CHICKEN1.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Michal Mrozek <michal.mrozek at intel.com>
Cc: Tony Ye <tony.ye at intel.com>
Cc: Rafael Antognolli <rafael.antognolli at intel.com>
Cc: Jason Ekstrand <jason at jlekstrand.net>
---
We need confirmation and acks from all three userspace components here.
Especially since my impression was some are for and some were against
whitelisting this one.
---
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 391f39b1fb26..37becdf77427 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -1276,6 +1276,9 @@ static void tgl_whitelist_build(struct intel_engine_cs *engine)
 
 		/* Wa_1806527549:tgl */
 		whitelist_reg(w, HIZ_CHICKEN);
+
+		/* WaEnablePreemptionGranularityControlByUMD:tgl */
+		whitelist_reg(w, GEN8_CS_CHICKEN1);
 		break;
 	default:
 		break;
-- 
2.20.1