drm/amdgpu: add drm buddy support to amdgpu

- Switch to drm buddy allocator
- Add resource cursor support for drm buddy

v2(Matthew Auld):
  - replace spinlock with mutex as we call kmem_cache_zalloc
    (..., GFP_KERNEL) in drm_buddy_alloc() function

  - lock drm_buddy_block_trim() function as it calls
    mark_free/mark_split are all globally visible

v3(Matthew Auld):
  - remove trim method error handling as we address the failure case
    at drm_buddy_block_trim() function

v4:
  - fix warnings reported by kernel test robot <lkp@intel.com>

v5:
  - fix merge conflict issue

v6:
  - fix warnings reported by kernel test robot <lkp@intel.com>

v7:
  - remove DRM_BUDDY_RANGE_ALLOCATION flag usage

v8:
  - keep DRM_BUDDY_RANGE_ALLOCATION flag usage
  - resolve conflicts created by drm/amdgpu: remove VRAM accounting v2

v9(Christian):
  - merged the below patch
     - drm/amdgpu: move vram inline functions into a header
  - rename label name as fallback
  - move struct amdgpu_vram_mgr to amdgpu_vram_mgr.h
  - remove unnecessary flags from struct amdgpu_vram_reservation
  - rewrite block NULL check condition
  - change else style as per coding standard
  - rewrite the node max size
  - add a helper function to fetch the first entry from the list

v10(Christian):
   - rename amdgpu_get_node() function name as amdgpu_vram_mgr_first_block

v11:
   - if size is not aligned with min_page_size, enable is_contiguous flag,
     therefore, the size round up to the power of two and trimmed to the
     original size.
v12:
   - rename the function names having prefix as amdgpu_vram_mgr_*()
   - modify the round_up() logic conforming to contiguous flag enablement
     or if size is not aligned to min_block_size
   - modify the trim logic
   - rename node as block wherever applicable

Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407224843.2416-1-Arunpravin.PaneerSelvam@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.h
new file mode 100644
index 000000000000..9a2db87186c7
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: MIT
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#ifndef __AMDGPU_VRAM_MGR_H__
+#define __AMDGPU_VRAM_MGR_H__
+
+#include <drm/drm_buddy.h>
+
+struct amdgpu_vram_mgr {
+	struct ttm_resource_manager manager;
+	struct drm_buddy mm;
+	/* protects access to buffer objects */
+	struct mutex lock;
+	struct list_head reservations_pending;
+	struct list_head reserved_pages;
+	atomic64_t vis_usage;
+	u64 default_page_size;
+};
+
+struct amdgpu_vram_mgr_resource {
+	struct ttm_resource base;
+	struct list_head blocks;
+	unsigned long flags;
+};
+
+static inline u64 amdgpu_vram_mgr_block_start(struct drm_buddy_block *block)
+{
+	return drm_buddy_block_offset(block);
+}
+
+static inline u64 amdgpu_vram_mgr_block_size(struct drm_buddy_block *block)
+{
+	return PAGE_SIZE << drm_buddy_block_order(block);
+}
+
+static inline struct drm_buddy_block *
+amdgpu_vram_mgr_first_block(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct drm_buddy_block, link);
+}
+
+static inline bool amdgpu_is_vram_mgr_blocks_contiguous(struct list_head *head)
+{
+	struct drm_buddy_block *block;
+	u64 start, size;
+
+	block = amdgpu_vram_mgr_first_block(head);
+	if (!block)
+		return false;
+
+	while (head != block->link.next) {
+		start = amdgpu_vram_mgr_block_start(block);
+		size = amdgpu_vram_mgr_block_size(block);
+
+		block = list_entry(block->link.next, struct drm_buddy_block, link);
+		if (start + size != amdgpu_vram_mgr_block_start(block))
+			return false;
+	}
+
+	return true;
+}
+
+static inline struct amdgpu_vram_mgr_resource *
+to_amdgpu_vram_mgr_resource(struct ttm_resource *res)
+{
+	return container_of(res, struct amdgpu_vram_mgr_resource, base);
+}
+
+#endif