Merge tag 'drm-intel-next-2018-09-06-2' of git://anongit.freedesktop.org/drm/drm...
[sfrench/cifs-2.6.git] / drivers / gpu / drm / i915 / gvt / gtt.c
index bbfb168a966565698c7fd9827ce4ad051edb2f7d..2402395a068da2fc5e83ba988aa76afccfe09f03 100644 (file)
@@ -1905,6 +1905,7 @@ static struct intel_vgpu_mm *intel_vgpu_create_ggtt_mm(struct intel_vgpu *vgpu)
                vgpu_free_mm(mm);
                return ERR_PTR(-ENOMEM);
        }
+       mm->ggtt_mm.last_partial_off = -1UL;
 
        return mm;
 }
@@ -1929,6 +1930,7 @@ void _intel_vgpu_mm_release(struct kref *mm_ref)
                invalidate_ppgtt_mm(mm);
        } else {
                vfree(mm->ggtt_mm.virtual_ggtt);
+               mm->ggtt_mm.last_partial_off = -1UL;
        }
 
        vgpu_free_mm(mm);
@@ -2181,6 +2183,62 @@ static int emulate_ggtt_mmio_write(struct intel_vgpu *vgpu, unsigned int off,
        memcpy((void *)&e.val64 + (off & (info->gtt_entry_size - 1)), p_data,
                        bytes);
 
+       /* If ggtt entry size is 8 bytes, and it's split into two 4 bytes
+        * write, we assume the two 4 bytes writes are consecutive.
+        * Otherwise, we abort and report error
+        */
+       if (bytes < info->gtt_entry_size) {
+               if (ggtt_mm->ggtt_mm.last_partial_off == -1UL) {
+                       /* the first partial part*/
+                       ggtt_mm->ggtt_mm.last_partial_off = off;
+                       ggtt_mm->ggtt_mm.last_partial_data = e.val64;
+                       return 0;
+               } else if ((g_gtt_index ==
+                               (ggtt_mm->ggtt_mm.last_partial_off >>
+                               info->gtt_entry_size_shift)) &&
+                       (off != ggtt_mm->ggtt_mm.last_partial_off)) {
+                       /* the second partial part */
+
+                       int last_off = ggtt_mm->ggtt_mm.last_partial_off &
+                               (info->gtt_entry_size - 1);
+
+                       memcpy((void *)&e.val64 + last_off,
+                               (void *)&ggtt_mm->ggtt_mm.last_partial_data +
+                               last_off, bytes);
+
+                       ggtt_mm->ggtt_mm.last_partial_off = -1UL;
+               } else {
+                       int last_offset;
+
+                       gvt_vgpu_err("failed to populate guest ggtt entry: abnormal ggtt entry write sequence, last_partial_off=%lx, offset=%x, bytes=%d, ggtt entry size=%d\n",
+                                       ggtt_mm->ggtt_mm.last_partial_off, off,
+                                       bytes, info->gtt_entry_size);
+
+                       /* set host ggtt entry to scratch page and clear
+                        * virtual ggtt entry as not present for last
+                        * partially write offset
+                        */
+                       last_offset = ggtt_mm->ggtt_mm.last_partial_off &
+                                       (~(info->gtt_entry_size - 1));
+
+                       ggtt_get_host_entry(ggtt_mm, &m, last_offset);
+                       ggtt_invalidate_pte(vgpu, &m);
+                       ops->set_pfn(&m, gvt->gtt.scratch_mfn);
+                       ops->clear_present(&m);
+                       ggtt_set_host_entry(ggtt_mm, &m, last_offset);
+                       ggtt_invalidate(gvt->dev_priv);
+
+                       ggtt_get_guest_entry(ggtt_mm, &e, last_offset);
+                       ops->clear_present(&e);
+                       ggtt_set_guest_entry(ggtt_mm, &e, last_offset);
+
+                       ggtt_mm->ggtt_mm.last_partial_off = off;
+                       ggtt_mm->ggtt_mm.last_partial_data = e.val64;
+
+                       return 0;
+               }
+       }
+
        if (ops->test_present(&e)) {
                gfn = ops->get_pfn(&e);
                m = e;