drm/i915: Do not modifiy reserved bit in gens that do not have IPC

IPC was only added in SKL+(actually we don't even enable for SKL due
WA) so without this change, driver was writing to a reserved bit.

Also removing the uncessary dev_priv->ipc_enabled = false; as now
gens without IPC will not have IPC enabled.

v2(Rodrigo):
- moved the new handling of WA #0477 to the next patch

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180918204714.27306-3-jose.souza@intel.com

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 1db9b83..e2ca045 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -6117,6 +6117,9 @@ void intel_enable_ipc(struct drm_i915_private *dev_priv)
 {
        u32 val;
 
+       if (!HAS_IPC(dev_priv))
+               return;
+
        /* Display WA #0477 WaDisableIPC: skl */
        if (IS_SKYLAKE(dev_priv))
                dev_priv->ipc_enabled = false;
@@ -6138,7 +6141,6 @@ void intel_enable_ipc(struct drm_i915_private *dev_priv)
 
 void intel_init_ipc(struct drm_i915_private *dev_priv)
 {
-       dev_priv->ipc_enabled = false;
        if (!HAS_IPC(dev_priv))
                return;