[PATCH 3/4] drm/i915: HSW PM - removing pcode read/write

[rodrigo.vivi at gmail.com (Rodrigo Vivi)]

Yet according to pm spec pcode read/write operations aren't necessary for HSW.

CC: Paulo Zanoni <paulo.r.zanoni at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at gmail.com>
---
 drivers/gpu/drm/i915/intel_pm.c | 50 ++++++++++++++++++++++-------------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index aea5fac..f6a7366 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2645,18 +2645,20 @@ static void gen6_enable_rps(struct drm_device *dev)
 		   GEN6_RP_UP_BUSY_AVG |
 		   (IS_HASWELL(dev) ? GEN7_RP_DOWN_IDLE_AVG : GEN6_RP_DOWN_IDLE_CONT));
 
-	ret = sandybridge_pcode_write(dev_priv, GEN6_PCODE_WRITE_MIN_FREQ_TABLE, 0);
-	if (!ret && (IS_GEN6(dev) || IS_IVYBRIDGE(dev))) {
-		pcu_mbox = 0;
-		ret = sandybridge_pcode_read(dev_priv, GEN6_READ_OC_PARAMS, &pcu_mbox);
-		if (!ret && (pcu_mbox & (1<<31))) { /* OC supported */
-			DRM_DEBUG_DRIVER("overclocking supported, adjusting frequency max from %dMHz to %dMHz\n",
-					 (dev_priv->rps.max_delay & 0xff) * 50,
-					 (pcu_mbox & 0xff) * 50);
-			dev_priv->rps.max_delay = pcu_mbox & 0xff;
+	if (!IS_HASWELL(dev)) {
+		ret = sandybridge_pcode_write(dev_priv, GEN6_PCODE_WRITE_MIN_FREQ_TABLE, 0);
+		if (!ret && (IS_GEN6(dev) || IS_IVYBRIDGE(dev))) {
+			pcu_mbox = 0;
+			ret = sandybridge_pcode_read(dev_priv, GEN6_READ_OC_PARAMS, &pcu_mbox);
+			if (!ret && (pcu_mbox & (1<<31))) { /* OC supported */
+				DRM_DEBUG_DRIVER("overclocking supported, adjusting frequency max from %dMHz to %dMHz\n",
+						 (dev_priv->rps.max_delay & 0xff) * 50,
+						 (pcu_mbox & 0xff) * 50);
+				dev_priv->rps.max_delay = pcu_mbox & 0xff;
+			}
+		} else {
+			DRM_DEBUG_DRIVER("Failed to set the min frequency\n");
 		}
-	} else {
-		DRM_DEBUG_DRIVER("Failed to set the min frequency\n");
 	}
 
 	gen6_set_rps(dev_priv->dev, (gt_perf_status & 0xff00) >> 8);
@@ -2670,18 +2672,20 @@ static void gen6_enable_rps(struct drm_device *dev)
 	/* enable all PM interrupts */
 	I915_WRITE(GEN6_PMINTRMSK, 0);
 
-	rc6vids = 0;
-	ret = sandybridge_pcode_read(dev_priv, GEN6_PCODE_READ_RC6VIDS, &rc6vids);
-	if (IS_GEN6(dev) && ret) {
-		DRM_DEBUG_DRIVER("Couldn't check for BIOS workaround\n");
-	} else if (IS_GEN6(dev) && (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
-		DRM_DEBUG_DRIVER("You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
-			  GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
-		rc6vids &= 0xffff00;
-		rc6vids |= GEN6_ENCODE_RC6_VID(450);
-		ret = sandybridge_pcode_write(dev_priv, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
-		if (ret)
-			DRM_ERROR("Couldn't fix incorrect rc6 voltage\n");
+	if (!IS_HASWELL(dev)) {
+		rc6vids = 0;
+		ret = sandybridge_pcode_read(dev_priv, GEN6_PCODE_READ_RC6VIDS, &rc6vids);
+		if (IS_GEN6(dev) && ret) {
+			DRM_DEBUG_DRIVER("Couldn't check for BIOS workaround\n");
+		} else if (IS_GEN6(dev) && (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
+			DRM_DEBUG_DRIVER("You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
+					 GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
+			rc6vids &= 0xffff00;
+			rc6vids |= GEN6_ENCODE_RC6_VID(450);
+			ret = sandybridge_pcode_write(dev_priv, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
+			if (ret)
+				DRM_ERROR("Couldn't fix incorrect rc6 voltage\n");
+		}
 	}
 
 	gen6_gt_force_wake_put(dev_priv);
-- 
1.8.1.4