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

In commit 5a7d202b1574, 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: 5a7d202b1574 ("drm/i915: Drop WaIncreaseLatencyIPCEnabled/1140 for cnl")
Cc: stable@vger.kernel.org # 5.3.x+
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430214654.51314-1-sultan@kerneltoast.com
(cherry picked from commit 690d22dafa88b82453516387b475664047a6bd14)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 8375054ba27d92b72f6b03a0e15f2703b5befdb5..a52986a9e7a68245f670746e1e3ba32ad90db042 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4992,7 +4992,7 @@ 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;