drm/i915: Rename pre-icl SAGV enable/disable functions

Give the pre-icl SAGV control functions a skl_ prefix instead
of the intel_ prefix to make it a bit more clear that they
are not some kind of universal things that can be called on
any platform. Also make the functions void since we never
use the return value anyway.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220309164948.10671-6-ville.syrjala@linux.intel.comReviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

drivers/gpu/drm/i915/intel_pm.c

@@ -57,7 +57,7 @@
 #include "vlv_sideband.h"
 #include "../../../platform/x86/intel_ips.h"
 
-static int intel_disable_sagv(struct drm_i915_private *dev_priv);
+static void skl_sagv_disable(struct drm_i915_private *dev_priv);
 
 struct drm_i915_clock_gating_funcs {
 	void (*init_clock_gating)(struct drm_i915_private *i915);
@@ -3707,7 +3707,7 @@ static void intel_sagv_init(struct drm_i915_private *i915)
 	 * For icl+ this was already determined by intel_bw_init_hw().
 	 */
 	if (DISPLAY_VER(i915) < 11)
-		intel_disable_sagv(i915);
+		skl_sagv_disable(i915);
 
 	drm_WARN_ON(&i915->drm, i915->sagv_status == I915_SAGV_UNKNOWN);
 
@@ -3737,16 +3737,15 @@ static void intel_sagv_init(struct drm_i915_private *i915)
  *  - All planes can enable watermarks for latencies >= SAGV engine block time
  *  - We're not using an interlaced display configuration
  */
-static int
-intel_enable_sagv(struct drm_i915_private *dev_priv)
+static void skl_sagv_enable(struct drm_i915_private *dev_priv)
 {
 	int ret;
 
 	if (!intel_has_sagv(dev_priv))
-		return 0;
+		return;
 
 	if (dev_priv->sagv_status == I915_SAGV_ENABLED)
-		return 0;
+		return;
 
 	drm_dbg_kms(&dev_priv->drm, "Enabling SAGV\n");
 	ret = snb_pcode_write(dev_priv, GEN9_PCODE_SAGV_CONTROL,
@@ -3761,26 +3760,24 @@ intel_enable_sagv(struct drm_i915_private *dev_priv)
 	if (IS_SKYLAKE(dev_priv) && ret == -ENXIO) {
 		drm_dbg(&dev_priv->drm, "No SAGV found on system, ignoring\n");
 		dev_priv->sagv_status = I915_SAGV_NOT_CONTROLLED;
-		return 0;
+		return;
 	} else if (ret < 0) {
 		drm_err(&dev_priv->drm, "Failed to enable SAGV\n");
-		return ret;
+		return;
 	}
 
 	dev_priv->sagv_status = I915_SAGV_ENABLED;
-	return 0;
 }
 
-static int
-intel_disable_sagv(struct drm_i915_private *dev_priv)
+static void skl_sagv_disable(struct drm_i915_private *dev_priv)
 {
 	int ret;
 
 	if (!intel_has_sagv(dev_priv))
-		return 0;
+		return;
 
 	if (dev_priv->sagv_status == I915_SAGV_DISABLED)
-		return 0;
+		return;
 
 	drm_dbg_kms(&dev_priv->drm, "Disabling SAGV\n");
 	/* bspec says to keep retrying for at least 1 ms */
@@ -3795,14 +3792,13 @@ intel_disable_sagv(struct drm_i915_private *dev_priv)
 	if (IS_SKYLAKE(dev_priv) && ret == -ENXIO) {
 		drm_dbg(&dev_priv->drm, "No SAGV found on system, ignoring\n");
 		dev_priv->sagv_status = I915_SAGV_NOT_CONTROLLED;
-		return 0;
+		return;
 	} else if (ret < 0) {
 		drm_err(&dev_priv->drm, "Failed to disable SAGV (%d)\n", ret);
-		return ret;
+		return;
 	}
 
 	dev_priv->sagv_status = I915_SAGV_DISABLED;
-	return 0;
 }
 
 static void skl_sagv_pre_plane_update(struct intel_atomic_state *state)
@@ -3815,7 +3811,7 @@ static void skl_sagv_pre_plane_update(struct intel_atomic_state *state)
 		return;
 
 	if (!intel_can_enable_sagv(i915, new_bw_state))
-		intel_disable_sagv(i915);
+		skl_sagv_disable(i915);
 }
 
 static void skl_sagv_post_plane_update(struct intel_atomic_state *state)
@@ -3828,7 +3824,7 @@ static void skl_sagv_post_plane_update(struct intel_atomic_state *state)
 		return;
 
 	if (intel_can_enable_sagv(i915, new_bw_state))
-		intel_enable_sagv(i915);
+		skl_sagv_enable(i915);
 }
 
 static void icl_sagv_pre_plane_update(struct intel_atomic_state *state)