diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 59b7ff5..5901810 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -559,12 +559,44 @@ static void __pdp_fini(struct i915_page_directory_pointer *pdp)
 	pdp->page_directory = NULL;
 }
 
+static struct
+i915_page_directory_pointer *alloc_pdp(struct drm_device *dev)
+{
+	struct i915_page_directory_pointer *pdp;
+	int ret = -ENOMEM;
+
+	WARN_ON(!USES_FULL_48BIT_PPGTT(dev));
+
+	pdp = kzalloc(sizeof(*pdp), GFP_KERNEL);
+	if (!pdp)
+		return ERR_PTR(-ENOMEM);
+
+	ret = __pdp_init(dev, pdp);
+	if (ret)
+		goto fail_bitmap;
+
+	ret = setup_px(dev, pdp);
+	if (ret)
+		goto fail_page_m;
+
+	return pdp;
+
+fail_page_m:
+	__pdp_fini(pdp);
+fail_bitmap:
+	kfree(pdp);
+
+	return ERR_PTR(ret);
+}
+
 static void free_pdp(struct drm_device *dev,
 		     struct i915_page_directory_pointer *pdp)
 {
 	__pdp_fini(pdp);
-	if (USES_FULL_48BIT_PPGTT(dev))
+	if (USES_FULL_48BIT_PPGTT(dev)) {
+		cleanup_px(dev, pdp);
 		kfree(pdp);
+	}
 }
 
 /* Broadwell Page Directory Pointer Descriptors */
@@ -758,12 +790,9 @@ static void gen8_free_scratch(struct i915_address_space *vm)
 	free_scratch_page(dev, vm->scratch_page);
 }
 
-static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
+static void gen8_ppgtt_cleanup_3lvl(struct drm_device *dev,
+				    struct i915_page_directory_pointer *pdp)
 {
-	struct i915_hw_ppgtt *ppgtt =
-		container_of(vm, struct i915_hw_ppgtt, base);
-	struct i915_page_directory_pointer *pdp = &ppgtt->pdp; /* FIXME: 48b */
-	struct drm_device *dev = ppgtt->base.dev;
 	int i;
 
 	for_each_set_bit(i, pdp->used_pdpes, I915_PDPES_PER_PDP(dev)) {
@@ -775,6 +804,31 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
 	}
 
 	free_pdp(dev, pdp);
+}
+
+static void gen8_ppgtt_cleanup_4lvl(struct i915_hw_ppgtt *ppgtt)
+{
+	int i;
+
+	for_each_set_bit(i, ppgtt->pml4.used_pml4es, GEN8_PML4ES_PER_PML4) {
+		if (WARN_ON(!ppgtt->pml4.pdps[i]))
+			continue;
+
+		gen8_ppgtt_cleanup_3lvl(ppgtt->base.dev, ppgtt->pml4.pdps[i]);
+	}
+
+	cleanup_px(ppgtt->base.dev, &ppgtt->pml4);
+}
+
+static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
+{
+	struct i915_hw_ppgtt *ppgtt =
+		container_of(vm, struct i915_hw_ppgtt, base);
+
+	if (!USES_FULL_48BIT_PPGTT(ppgtt->base.dev))
+		gen8_ppgtt_cleanup_3lvl(ppgtt->base.dev, &ppgtt->pdp);
+	else
+		gen8_ppgtt_cleanup_4lvl(ppgtt);
 
 	gen8_free_scratch(vm);
 }
@@ -957,14 +1011,15 @@ static void mark_tlbs_dirty(struct i915_hw_ppgtt *ppgtt)
 	ppgtt->pd_dirty_rings = INTEL_INFO(ppgtt->base.dev)->ring_mask;
 }
 
-static int gen8_alloc_va_range(struct i915_address_space *vm,
-			       uint64_t start, uint64_t length)
+static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm,
+				    struct i915_page_directory_pointer *pdp,
+				    uint64_t start,
+				    uint64_t length)
 {
 	struct i915_hw_ppgtt *ppgtt =
 		container_of(vm, struct i915_hw_ppgtt, base);
 	unsigned long *new_page_dirs, **new_page_tables;
 	struct drm_device *dev = vm->dev;
-	struct i915_page_directory_pointer *pdp = &ppgtt->pdp; /* FIXME: 48b */
 	struct i915_page_directory *pd;
 	const uint64_t orig_start = start;
 	const uint64_t orig_length = length;
@@ -1065,6 +1120,79 @@ err_out:
 	return ret;
 }
 
+static int gen8_alloc_va_range_4lvl(struct i915_address_space *vm,
+				    struct i915_pml4 *pml4,
+				    uint64_t start,
+				    uint64_t length)
+{
+	DECLARE_BITMAP(new_pdps, GEN8_PML4ES_PER_PML4);
+	struct i915_page_directory_pointer *pdp;
+	const uint64_t orig_start = start;
+	const uint64_t orig_length = length;
+	uint64_t temp, pml4e;
+	int ret = 0;
+
+	/* Do the pml4 allocations first, so we don't need to track the newly
+	 * allocated tables below the pdp */
+	bitmap_zero(new_pdps, GEN8_PML4ES_PER_PML4);
+
+	/* The pagedirectory and pagetable allocations are done in the shared 3
+	 * and 4 level code. Just allocate the pdps.
+	 */
+	gen8_for_each_pml4e(pdp, pml4, start, length, temp, pml4e) {
+		if (!test_bit(pml4e, pml4->used_pml4es)) {
+			pdp = alloc_pdp(vm->dev);
+			if (IS_ERR(pdp))
+				goto err_out;
+
+			pml4->pdps[pml4e] = pdp;
+			__set_bit(pml4e, new_pdps);
+			trace_i915_page_directory_pointer_entry_alloc(vm,
+								      pml4e,
+								      start,
+								      GEN8_PML4E_SHIFT);
+		}
+	}
+
+	WARN(bitmap_weight(new_pdps, GEN8_PML4ES_PER_PML4) > 2,
+	     "The allocation has spanned more than 512GB. "
+	     "It is highly likely this is incorrect.");
+
+	start = orig_start;
+	length = orig_length;
+
+	gen8_for_each_pml4e(pdp, pml4, start, length, temp, pml4e) {
+		WARN_ON(!pdp);
+
+		ret = gen8_alloc_va_range_3lvl(vm, pdp, start, length);
+		if (ret)
+			goto err_out;
+	}
+
+	bitmap_or(pml4->used_pml4es, new_pdps, pml4->used_pml4es,
+		  GEN8_PML4ES_PER_PML4);
+
+	return 0;
+
+err_out:
+	for_each_set_bit(pml4e, new_pdps, GEN8_PML4ES_PER_PML4)
+		gen8_ppgtt_cleanup_3lvl(vm->dev, pml4->pdps[pml4e]);
+
+	return ret;
+}
+
+static int gen8_alloc_va_range(struct i915_address_space *vm,
+			       uint64_t start, uint64_t length)
+{
+	struct i915_hw_ppgtt *ppgtt =
+		container_of(vm, struct i915_hw_ppgtt, base);
+
+	if (USES_FULL_48BIT_PPGTT(vm->dev))
+		return gen8_alloc_va_range_4lvl(vm, &ppgtt->pml4, start, length);
+	else
+		return gen8_alloc_va_range_3lvl(vm, &ppgtt->pdp, start, length);
+}
+
 /*
  * GEN8 legacy ppgtt programming is accomplished through a max 4 PDP registers
  * with a net effect resembling a 2-level page table in normal x86 terms. Each
@@ -1090,9 +1218,14 @@ static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
 
 	ppgtt->switch_mm = gen8_mm_switch;
 
-	if (!USES_FULL_48BIT_PPGTT(ppgtt->base.dev)) {
-		ret = __pdp_init(false, &ppgtt->pdp);
+	if (USES_FULL_48BIT_PPGTT(ppgtt->base.dev)) {
+		ret = setup_px(ppgtt->base.dev, &ppgtt->pml4);
+		if (ret)
+			goto free_scratch;
 
+		ppgtt->base.total = 1ULL << 48;
+	} else {
+		ret = __pdp_init(false, &ppgtt->pdp);
 		if (ret)
 			goto free_scratch;
 
@@ -1104,10 +1237,10 @@ static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
 			 * 2GiB).
 			 */
 			ppgtt->base.total = to_i915(ppgtt->base.dev)->gtt.base.total;
-	} else {
-		ppgtt->base.total = 1ULL << 48;
-		ret = -EPERM; /* Not yet implemented */
-		goto free_scratch;
+
+		trace_i915_page_directory_pointer_entry_alloc(&ppgtt->base,
+							      0, 0,
+							      GEN8_PML4E_SHIFT);
 	}
 
 	return 0;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 04bc66f..e63ef07 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -95,6 +95,7 @@ typedef uint64_t gen8_pde_t;
  */
 #define GEN8_PML4ES_PER_PML4		512
 #define GEN8_PML4E_SHIFT		39
+#define GEN8_PML4E_MASK			(GEN8_PML4ES_PER_PML4 - 1)
 #define GEN8_PDPE_SHIFT			30
 /* NB: GEN8_PDPE_MASK is untrue for 32b platforms, but it has no impact on 32b page
  * tables */
@@ -465,6 +466,15 @@ static inline uint32_t gen6_pde_index(uint32_t addr)
 	     temp = min(temp, length),					\
 	     start += temp, length -= temp)
 
+#define gen8_for_each_pml4e(pdp, pml4, start, length, temp, iter)	\
+	for (iter = gen8_pml4e_index(start);	\
+	     pdp = (pml4)->pdps[iter], \
+	     length > 0 && iter < GEN8_PML4ES_PER_PML4; \
+	     iter++,				\
+	     temp = ALIGN(start+1, 1ULL << GEN8_PML4E_SHIFT) - start,	\
+	     temp = min(temp, length),					\
+	     start += temp, length -= temp)
+
 static inline uint32_t gen8_pte_index(uint64_t address)
 {
 	return i915_pte_index(address, GEN8_PDE_SHIFT);
@@ -482,8 +492,7 @@ static inline uint32_t gen8_pdpe_index(uint64_t address)
 
 static inline uint32_t gen8_pml4e_index(uint64_t address)
 {
-	WARN_ON(1); /* For 64B */
-	return 0;
+	return (address >> GEN8_PML4E_SHIFT) & GEN8_PML4E_MASK;
 }
 
 static inline size_t gen8_pte_count(uint64_t address, uint64_t length)
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index f230d76..e6b5c74 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -221,6 +221,14 @@ DEFINE_EVENT_PRINT(i915_px_entry, i915_page_directory_entry_alloc,
 			     __entry->vm, __entry->px, __entry->start, __entry->end)
 );
 
+DEFINE_EVENT_PRINT(i915_px_entry, i915_page_directory_pointer_entry_alloc,
+		   TP_PROTO(struct i915_address_space *vm, u32 pml4e, u64 start, u64 pml4e_shift),
+		   TP_ARGS(vm, pml4e, start, pml4e_shift),
+
+		   TP_printk("vm=%p, pml4e=%d (0x%llx-0x%llx)",
+			     __entry->vm, __entry->px, __entry->start, __entry->end)
+);
+
 /* Avoid extra math because we only support two sizes. The format is defined by
  * bitmap_scnprintf. Each 32 bits is 8 HEX digits followed by comma */
 #define TRACE_PT_SIZE(bits) \
