drm/i915: Don't enable WaIncreaseLatencyIPCEnabled when IPC is disabled

[ Upstream commit 421abe2 ]

In commit 5a7d202, a logical AND was erroneously changed to an OR,
causing WaIncreaseLatencyIPCEnabled to be enabled unconditionally for
kabylake and coffeelake, even when IPC is disabled. Fix the logic so
that WaIncreaseLatencyIPCEnabled is only used when IPC is enabled.

Fixes: 5a7d202 ("drm/i915: Drop WaIncreaseLatencyIPCEnabled/1140 for cnl")
Cc: [email protected] # 5.3.x+
Signed-off-by: Sultan Alsawaf <[email protected]>
Signed-off-by: Ville Syrjälä <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit 690d22d)
Signed-off-by: Rodrigo Vivi <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

drivers/gpu/drm/i915/intel_pm.c

@@ -4784,7 +4784,7 @@ static void skl_compute_plane_wm(const struct intel_crtc_state *crtc_state,
 	 * WaIncreaseLatencyIPCEnabled: kbl,cfl
 	 * Display WA #1141: kbl,cfl
 	 */
-	if ((IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv)) ||
+	if ((IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv)) &&
 	    dev_priv->ipc_enabled)
 		latency += 4;