[Intel-gfx] [PATCH 5/5] drm/i915: Setup static bias for GPU

[deepak.s at linux.intel.com]

From: Deepak S <deepak.s at linux.intel.com>

Based on the spec, Setting up static BIAS for GPU to improve the
rps performace.

Signed-off-by: Deepak S <deepak.s at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h |  5 +++++
 drivers/gpu/drm/i915/intel_pm.c | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 55143cb..dd776df 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -662,6 +662,11 @@ enum skl_disp_power_wells {
 #define   FB_FMAX_VMIN_FREQ_LO_SHIFT		27
 #define   FB_FMAX_VMIN_FREQ_LO_MASK		0xf8000000
 
+#define VLV_IOSFB_RPS_OVERRIDE	0x04
+#define VLV_OVERRIDE_RPS_MASK	1
+#define VLV_ENABLE_BIAS_SHARE	(1 << 1)
+#define VLV_BIAS_VAL	(6 << 2)
+
 #define VLV_CZ_CLOCK_TO_MILLI_SEC		100000
 #define VLV_RP_UP_EI_THRESHOLD			90
 #define VLV_RP_DOWN_EI_THRESHOLD		70
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 7716be9..5bbb047 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4841,6 +4841,12 @@ static void cherryview_enable_rps(struct drm_device *dev)
 		   GEN6_RP_UP_BUSY_AVG |
 		   GEN6_RP_DOWN_IDLE_AVG);
 
+	/* Setting Fixed Bias */
+	val = VLV_OVERRIDE_RPS_MASK |
+		  VLV_ENABLE_BIAS_SHARE |
+		  VLV_BIAS_VAL;
+	vlv_punit_write(dev_priv, VLV_IOSFB_RPS_OVERRIDE, val);
+
 	val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
 
 	/* RPS code assumes GPLL is used */
@@ -4951,6 +4957,12 @@ static void valleyview_enable_rps(struct drm_device *dev)
 
 	I915_WRITE(GEN6_RC_CONTROL, rc6_mode);
 
+	/* Setting Fixed Bias */
+	val = VLV_OVERRIDE_RPS_MASK |
+		  VLV_ENABLE_BIAS_SHARE |
+		  VLV_BIAS_VAL;
+	vlv_punit_write(dev_priv, VLV_IOSFB_RPS_OVERRIDE, val);
+
 	val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
 
 	/* RPS code assumes GPLL is used */
-- 
1.9.1