[PATCH 04/59] drm/i915/cnl: Get RC6 working.

Timo Aaltonen tjaalton at ubuntu.com
Wed Mar 28 15:30:14 UTC 2018


From: Rodrigo Vivi <rodrigo.vivi at intel.com>

BugLink: http://bugs.launchpad.net/bugs/1757573

On CNL, individual wake rate limit was added to each engine.

GT can only go to RC6 if both Render and Media engines are
individually qualified. So we need to set their individual
wake rate limit.

+-----------------+---------------+--------------+--------------+
|                 |    GT RC6     |  Render C6   |   Media C6   |
+-----------------+---------------+--------------+--------------+
| Wake rate limit | 0xA09C[31:16] | 0xA09C[15:0] | 0xA0A0[15:0] |
+-----------------+---------------+--------------+--------------+

v2: - Tune Render and Media wake rate values according to some extra
      info I got from HW engineers. Value can be tuned, but for now
      these are the recommended values.
    - Fix typos pointed by James.

Cc: Nathan Ciobanu <nathan.d.ciobanu at intel.com>
Cc: Wayne Boyer <wayne.boyer at intel.com>
Cc: Joe Konno <joe.konno at linux.intel.com>
Cc: David Weinehall <david.weinehall at linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
Reviewed-by: James Ausmus <james.ausmus at intel.com>
Reviewed-by: David Weinehall <david.weinehall at linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171023224612.27208-1-rodrigo.vivi@intel.com
(cherry picked from commit 0aab201b4ad10fa530e4d12f8ea30b6f0a0540bd)
Signed-off-by: Timo Aaltonen <timo.aaltonen at canonical.com>
---
 drivers/gpu/drm/i915/i915_reg.h |  1 +
 drivers/gpu/drm/i915/intel_pm.c | 15 +++++++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 7923dfd9963c..861b29f57c09 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7905,6 +7905,7 @@ enum {
 #define GEN6_RC1_WAKE_RATE_LIMIT		_MMIO(0xA098)
 #define GEN6_RC6_WAKE_RATE_LIMIT		_MMIO(0xA09C)
 #define GEN6_RC6pp_WAKE_RATE_LIMIT		_MMIO(0xA0A0)
+#define GEN10_MEDIA_WAKE_RATE_LIMIT		_MMIO(0xA0A0)
 #define GEN6_RC_EVALUATION_INTERVAL		_MMIO(0xA0A8)
 #define GEN6_RC_IDLE_HYSTERSIS			_MMIO(0xA0AC)
 #define GEN6_RC_SLEEP				_MMIO(0xA0B0)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index f0d0dbab4150..b68d444b1791 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -6614,12 +6614,19 @@ static void gen9_enable_rc6(struct drm_i915_private *dev_priv)
 	I915_WRITE(GEN6_RC_CONTROL, 0);
 
 	/* 2b: Program RC6 thresholds.*/
-
-	/* WaRsDoubleRc6WrlWithCoarsePowerGating: Doubling WRL only when CPG is enabled */
-	if (IS_SKYLAKE(dev_priv))
+	if (INTEL_GEN(dev_priv) >= 10) {
+		I915_WRITE(GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
+		I915_WRITE(GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
+	} else if (IS_SKYLAKE(dev_priv)) {
+		/*
+		 * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only
+		 * when CPG is enabled
+		 */
 		I915_WRITE(GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16);
-	else
+	} else {
 		I915_WRITE(GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16);
+	}
+
 	I915_WRITE(GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
 	I915_WRITE(GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
 	for_each_engine(engine, dev_priv, id)
-- 
2.15.1





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