drm/i915/bdw: Populate lrc with aliasing ppgtt if required

A previous commit broke aliasing PPGTT for lrc, resulting in a kernel oops
on boot. Add a check so that is full PPGTT is not in use the context is
populated with the aliasing PPGTT.

Issue: VIZ-4278
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index c096b9b7f22a..b54f31207cac 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1452,12 +1452,17 @@ static int
 populate_lr_context(struct intel_context *ctx, struct drm_i915_gem_object *ctx_obj,
                     struct intel_engine_cs *ring, struct intel_ringbuffer *ringbuf)
 {
+        struct drm_device *dev = ring->dev;
+        struct drm_i915_private *dev_priv = dev->dev_private;
         struct drm_i915_gem_object *ring_obj = ringbuf->obj;
         struct i915_hw_ppgtt *ppgtt = ctx->ppgtt;
         struct page *page;
         uint32_t *reg_state;
         int ret;
 
+        if (!ppgtt)
+                ppgtt = dev_priv->mm.aliasing_ppgtt;
+
         ret = i915_gem_object_set_to_cpu_domain(ctx_obj, true);
         if (ret) {
                 DRM_DEBUG_DRIVER("Could not set to CPU domain\n");