drm/i915/psr: Move logic to get TPS registers values to another function

This will make hsw_activate_psr1() more easy to read and will make
future modification to TPS registers more easy to review and read.

v4: Rename new function to intel_psr1_get_tp_time() (Dhinakaran and
Rodrigo)

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190312195743.8829-2-jose.souza@intel.com

drivers/gpu/drm/i915/intel_psr.c

@@ -434,30 +434,10 @@ static void intel_psr_enable_sink(struct intel_dp *intel_dp)
 	drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
 }
 
-static void hsw_activate_psr1(struct intel_dp *intel_dp)
+static u32 intel_psr1_get_tp_time(struct intel_dp *intel_dp)
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
-	u32 max_sleep_time = 0x1f;
-	u32 val = EDP_PSR_ENABLE;
-
-	/* Let's use 6 as the minimum to cover all known cases including the
-	 * off-by-one issue that HW has in some cases.
-	 */
-	int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
-
-	/* sink_sync_latency of 8 means source has to wait for more than 8
-	 * frames, we'll go with 9 frames for now
-	 */
-	idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency + 1);
-
-	val |= idle_frames << EDP_PSR_IDLE_FRAME_SHIFT;
-
-	val |= max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT;
-	if (IS_HASWELL(dev_priv))
-		val |= EDP_PSR_MIN_LINK_ENTRY_TIME_8_LINES;
-
-	if (dev_priv->psr.link_standby)
-		val |= EDP_PSR_LINK_STANDBY;
+	u32 val = 0;
 
 	if (dev_priv->vbt.psr.tp1_wakeup_time_us == 0)
 		val |= EDP_PSR_TP1_TIME_0us;
@@ -483,6 +463,35 @@ static void hsw_activate_psr1(struct intel_dp *intel_dp)
 	else
 		val |= EDP_PSR_TP1_TP2_SEL;
 
+	return val;
+}
+
+static void hsw_activate_psr1(struct intel_dp *intel_dp)
+{
+	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+	u32 max_sleep_time = 0x1f;
+	u32 val = EDP_PSR_ENABLE;
+
+	/* Let's use 6 as the minimum to cover all known cases including the
+	 * off-by-one issue that HW has in some cases.
+	 */
+	int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
+
+	/* sink_sync_latency of 8 means source has to wait for more than 8
+	 * frames, we'll go with 9 frames for now
+	 */
+	idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency + 1);
+	val |= idle_frames << EDP_PSR_IDLE_FRAME_SHIFT;
+
+	val |= max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT;
+	if (IS_HASWELL(dev_priv))
+		val |= EDP_PSR_MIN_LINK_ENTRY_TIME_8_LINES;
+
+	if (dev_priv->psr.link_standby)
+		val |= EDP_PSR_LINK_STANDBY;
+
+	val |= intel_psr1_get_tp_time(intel_dp);
+
 	if (INTEL_GEN(dev_priv) >= 8)
 		val |= EDP_PSR_CRC_ENABLE;