drm/i915/ttm: switch over to ttm_buddy_man

Move back to the buddy allocator for managing device local memory, and
restore the lost mock selftests. Keep around the range manager related
bits, since we likely need this for managing stolen at some point. For
stolen we also don't need to reserve anything so no need to support a
generic reserve interface.

v2(Thomas):
    - bo->page_alignment is in page units, not bytes

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616152501.394518-6-matthew.auld@intel.com

1 files changed, 46 insertions, 76 deletions

diff --git a/drivers/gpu/drm/i915/intel_region_ttm.c b/drivers/gpu/drm/i915/intel_region_ttm.c
index f9d616544728..052253c81e98 100644
--- a/drivers/gpu/drm/i915/intel_region_ttm.c
+++ b/drivers/gpu/drm/i915/intel_region_ttm.c
@@ -8,6 +8,7 @@
 
 #include "i915_drv.h"
 #include "i915_scatterlist.h"
+#include "i915_ttm_buddy_manager.h"
 
 #include "intel_region_ttm.h"
 
@@ -67,72 +68,28 @@ int intel_region_to_ttm_type(const struct intel_memory_region *mem)
 	return type;
 }
 
-static struct ttm_resource *
-intel_region_ttm_resource_reserve(struct intel_memory_region *mem,
-			      resource_size_t offset,
-			      resource_size_t size)
-{
-	struct ttm_resource_manager *man = mem->region_private;
-	struct ttm_place place = {};
-	struct ttm_buffer_object mock_bo = {};
-	struct ttm_resource *res;
-	int ret;
-
-	/*
-	 * Having to use a mock_bo is unfortunate but stems from some
-	 * drivers having private managers that insist to know what the
-	 * allocate memory is intended for, using it to send private
-	 * data to the manager. Also recently the bo has been used to send
-	 * alignment info to the manager. Assume that apart from the latter,
-	 * none of the managers we use will ever access the buffer object
-	 * members, hoping we can pass the alignment info in the
-	 * struct ttm_place in the future.
-	 */
-
-	place.fpfn = offset >> PAGE_SHIFT;
-	place.lpfn = place.fpfn + (size >> PAGE_SHIFT);
-	mock_bo.base.size = size;
-	ret = man->func->alloc(man, &mock_bo, &place, &res);
-	if (ret == -ENOSPC)
-		ret = -ENXIO;
-
-	return ret ? ERR_PTR(ret) : res;
-}
-
 /**
- * intel_region_ttm_resource_free - Free a resource allocated from a resource manager
- * @mem: The region the resource was allocated from.
- * @res: The opaque resource representing an allocation.
+ * intel_region_ttm_init - Initialize a memory region for TTM.
+ * @mem: The region to initialize.
+ *
+ * This function initializes a suitable TTM resource manager for the
+ * region, and if it's a LMEM region type, attaches it to the TTM
+ * device. MOCK regions are NOT attached to the TTM device, since we don't
+ * have one for the mock selftests.
+ *
+ * Return: 0 on success, negative error code on failure.
  */
-void intel_region_ttm_resource_free(struct intel_memory_region *mem,
-				    struct ttm_resource *res)
-{
-	struct ttm_resource_manager *man = mem->region_private;
-
-	man->func->free(man, res);
-}
-
-static const struct intel_memory_region_private_ops priv_ops = {
-	.reserve = intel_region_ttm_resource_reserve,
-	.free = intel_region_ttm_resource_free,
-};
-
 int intel_region_ttm_init(struct intel_memory_region *mem)
 {
 	struct ttm_device *bdev = &mem->i915->bdev;
 	int mem_type = intel_region_to_ttm_type(mem);
 	int ret;
 
-	ret = ttm_range_man_init(bdev, mem_type, false,
-				 resource_size(&mem->region) >> PAGE_SHIFT);
+	ret = i915_ttm_buddy_man_init(bdev, mem_type, false,
+				      resource_size(&mem->region), PAGE_SIZE);
 	if (ret)
 		return ret;
 
-	mem->chunk_size = PAGE_SIZE;
-	mem->max_order =
-		get_order(rounddown_pow_of_two(resource_size(&mem->region)));
-	mem->is_range_manager = true;
-	mem->priv_ops = &priv_ops;
 	mem->region_private = ttm_manager_type(bdev, mem_type);
 
 	return 0;
@@ -150,8 +107,8 @@ void intel_region_ttm_fini(struct intel_memory_region *mem)
 {
 	int ret;
 
-	ret = ttm_range_man_fini(&mem->i915->bdev,
-				 intel_region_to_ttm_type(mem));
+	ret = i915_ttm_buddy_man_fini(&mem->i915->bdev,
+				      intel_region_to_ttm_type(mem));
 	GEM_WARN_ON(ret);
 	mem->region_private = NULL;
 }
@@ -171,12 +128,15 @@ void intel_region_ttm_fini(struct intel_memory_region *mem)
 struct sg_table *intel_region_ttm_resource_to_st(struct intel_memory_region *mem,
 						 struct ttm_resource *res)
 {
-	struct ttm_range_mgr_node *range_node =
-		container_of(res, typeof(*range_node), base);
+	if (mem->is_range_manager) {
+		struct ttm_range_mgr_node *range_node =
+			to_ttm_range_mgr_node(res);
 
-	GEM_WARN_ON(!mem->is_range_manager);
-	return i915_sg_from_mm_node(&range_node->mm_nodes[0],
-				    mem->region.start);
+		return i915_sg_from_mm_node(&range_node->mm_nodes[0],
+					    mem->region.start);
+	} else {
+		return i915_sg_from_buddy_resource(res, mem->region.start);
+	}
 }
 
 #ifdef CONFIG_DRM_I915_SELFTEST
@@ -206,25 +166,35 @@ intel_region_ttm_resource_alloc(struct intel_memory_region *mem,
 	struct ttm_resource *res;
 	int ret;
 
-	/*
-	 * We ignore the flags for now since we're using the range
-	 * manager and contigous and min page size would be fulfilled
-	 * by default if size is min page size aligned.
-	 */
 	mock_bo.base.size = size;
-
-	if (mem->is_range_manager) {
-		if (size >= SZ_1G)
-			mock_bo.page_alignment = SZ_1G >> PAGE_SHIFT;
-		else if (size >= SZ_2M)
-			mock_bo.page_alignment = SZ_2M >> PAGE_SHIFT;
-		else if (size >= SZ_64K)
-			mock_bo.page_alignment = SZ_64K >> PAGE_SHIFT;
-	}
+	mock_bo.page_alignment = 1;
+	place.flags = flags;
 
 	ret = man->func->alloc(man, &mock_bo, &place, &res);
 	if (ret == -ENOSPC)
 		ret = -ENXIO;
 	return ret ? ERR_PTR(ret) : res;
 }
+
 #endif
+
+void intel_region_ttm_node_free(struct intel_memory_region *mem,
+				struct ttm_resource *res)
+{
+	struct ttm_resource_manager *man = mem->region_private;
+
+	man->func->free(man, res);
+}
+
+/**
+ * intel_region_ttm_resource_free - Free a resource allocated from a resource manager
+ * @mem: The region the resource was allocated from.
+ * @res: The opaque resource representing an allocation.
+ */
+void intel_region_ttm_resource_free(struct intel_memory_region *mem,
+				    struct ttm_resource *res)
+{
+	struct ttm_resource_manager *man = mem->region_private;
+
+	man->func->free(man, res);
+}