[Intel-gfx] [RFC PATCH 18/42] drm/i915/lmem: support CPU relocations

[Matthew Auld]

We need to support doing relocations from the CPU when dealing with LMEM
objects.

Signed-off-by: Matthew Auld <matthew.auld at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c | 67 ++++++++++++++++++----
 1 file changed, 56 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 02adcaf6ebea..390691128c1d 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -265,6 +265,7 @@ struct i915_execbuffer {
 		bool has_llc : 1;
 		bool has_fence : 1;
 		bool needs_unfenced : 1;
+		bool is_lmem : 1;
 
 		struct i915_request *rq;
 		u32 *rq_cmd;
@@ -973,6 +974,7 @@ static void reloc_cache_init(struct reloc_cache *cache,
 	cache->use_64bit_reloc = HAS_64BIT_RELOC(i915);
 	cache->has_fence = cache->gen < 4;
 	cache->needs_unfenced = INTEL_INFO(i915)->unfenced_needs_alignment;
+	cache->is_lmem = false;
 	cache->node.allocated = false;
 	cache->rq = NULL;
 	cache->rq_size = 0;
@@ -1027,16 +1029,23 @@ static void reloc_cache_reset(struct reloc_cache *cache)
 		i915_gem_obj_finish_shmem_access((struct drm_i915_gem_object *)cache->node.mm);
 	} else {
 		wmb();
-		io_mapping_unmap_atomic((void __iomem *)vaddr);
-		if (cache->node.allocated) {
-			struct i915_ggtt *ggtt = cache_to_ggtt(cache);
-
-			ggtt->vm.clear_range(&ggtt->vm,
-					     cache->node.start,
-					     cache->node.size);
-			drm_mm_remove_node(&cache->node);
+
+		if (cache->is_lmem) {
+			io_mapping_unmap_atomic((void __iomem *)vaddr);
+			i915_gem_object_unpin_pages((struct drm_i915_gem_object *)cache->node.mm);
+			cache->is_lmem = false;
 		} else {
-			i915_vma_unpin((struct i915_vma *)cache->node.mm);
+			io_mapping_unmap_atomic((void __iomem *)vaddr);
+			if (cache->node.allocated) {
+				struct i915_ggtt *ggtt = cache_to_ggtt(cache);
+
+				ggtt->vm.clear_range(&ggtt->vm,
+						     cache->node.start,
+						     cache->node.size);
+				drm_mm_remove_node(&cache->node);
+			} else {
+				i915_vma_unpin((struct i915_vma *)cache->node.mm);
+			}
 		}
 	}
 
@@ -1076,6 +1085,38 @@ static void *reloc_kmap(struct drm_i915_gem_object *obj,
 	return vaddr;
 }
 
+static void *reloc_lmem(struct drm_i915_gem_object *obj,
+			struct reloc_cache *cache,
+			unsigned long page)
+{
+	void *vaddr;
+	int err;
+
+	GEM_BUG_ON(use_cpu_reloc(cache, obj));
+
+	if (cache->vaddr) {
+		io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
+	} else {
+		err = i915_gem_object_set_to_wc_domain(obj, true);
+		if (err)
+			return ERR_PTR(err);
+
+		err = i915_gem_object_pin_pages(obj);
+		if (err)
+			return ERR_PTR(err);
+
+		cache->node.mm = (void *)obj;
+		cache->is_lmem = true;
+	}
+
+	vaddr = i915_gem_object_lmem_io_map_page(obj, page);
+
+	cache->vaddr = (unsigned long)vaddr;
+	cache->page = page;
+
+	return vaddr;
+}
+
 static void *reloc_iomap(struct drm_i915_gem_object *obj,
 			 struct reloc_cache *cache,
 			 unsigned long page)
@@ -1150,8 +1191,12 @@ static void *reloc_vaddr(struct drm_i915_gem_object *obj,
 		vaddr = unmask_page(cache->vaddr);
 	} else {
 		vaddr = NULL;
-		if ((cache->vaddr & KMAP) == 0)
-			vaddr = reloc_iomap(obj, cache, page);
+		if ((cache->vaddr & KMAP) == 0) {
+			if (i915_gem_object_is_lmem(obj))
+				vaddr = reloc_lmem(obj, cache, page);
+			else
+				vaddr = reloc_iomap(obj, cache, page);
+		}
 		if (!vaddr)
 			vaddr = reloc_kmap(obj, cache, page);
 	}
-- 
2.20.1