1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_res_cursor.h b/drivers/gpu/drm/xe/xe_res_cursor.h
new file mode 100644
index 000000000000..f54409850d74
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_res_cursor.h
@@ -0,0 +1,226 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Copyright 2020 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 __XE_RES_CURSOR_H__
+#define __XE_RES_CURSOR_H__
+
+#include <linux/scatterlist.h>
+
+#include <drm/drm_mm.h>
+#include <drm/ttm/ttm_placement.h>
+#include <drm/ttm/ttm_range_manager.h>
+#include <drm/ttm/ttm_resource.h>
+#include <drm/ttm/ttm_tt.h>
+
+#include "xe_bo.h"
+#include "xe_macros.h"
+#include "xe_ttm_vram_mgr.h"
+
+/* state back for walking over vram_mgr and gtt_mgr allocations */
+struct xe_res_cursor {
+	u64 start;
+	u64 size;
+	u64 remaining;
+	void *node;
+	u32 mem_type;
+	struct scatterlist *sgl;
+};
+
+/**
+ * xe_res_first - initialize a xe_res_cursor
+ *
+ * @res: TTM resource object to walk
+ * @start: Start of the range
+ * @size: Size of the range
+ * @cur: cursor object to initialize
+ *
+ * Start walking over the range of allocations between @start and @size.
+ */
+static inline void xe_res_first(struct ttm_resource *res,
+				u64 start, u64 size,
+				struct xe_res_cursor *cur)
+{
+	struct drm_buddy_block *block;
+	struct list_head *head, *next;
+
+	cur->sgl = NULL;
+	if (!res)
+		goto fallback;
+
+	XE_BUG_ON(start + size > res->size);
+
+	cur->mem_type = res->mem_type;
+
+	switch (cur->mem_type) {
+	case XE_PL_VRAM0:
+	case XE_PL_VRAM1:
+		head = &to_xe_ttm_vram_mgr_resource(res)->blocks;
+
+		block = list_first_entry_or_null(head,
+						 struct drm_buddy_block,
+						 link);
+		if (!block)
+			goto fallback;
+
+		while (start >= xe_ttm_vram_mgr_block_size(block)) {
+			start -= xe_ttm_vram_mgr_block_size(block);
+
+			next = block->link.next;
+			if (next != head)
+				block = list_entry(next, struct drm_buddy_block,
+						   link);
+		}
+
+		cur->start = xe_ttm_vram_mgr_block_start(block) + start;
+		cur->size = min(xe_ttm_vram_mgr_block_size(block) - start,
+				size);
+		cur->remaining = size;
+		cur->node = block;
+		break;
+	default:
+		goto fallback;
+	}
+
+	return;
+
+fallback:
+	cur->start = start;
+	cur->size = size;
+	cur->remaining = size;
+	cur->node = NULL;
+	cur->mem_type = XE_PL_TT;
+	XE_WARN_ON(res && start + size > res->size);
+	return;
+}
+
+static inline void __xe_res_sg_next(struct xe_res_cursor *cur)
+{
+	struct scatterlist *sgl = cur->sgl;
+	u64 start = cur->start;
+
+	while (start >= sg_dma_len(sgl)) {
+		start -= sg_dma_len(sgl);
+		sgl = sg_next(sgl);
+		XE_BUG_ON(!sgl);
+	}
+
+	cur->start = start;
+	cur->size = sg_dma_len(sgl) - start;
+	cur->sgl = sgl;
+}
+
+/**
+ * xe_res_first_sg - initialize a xe_res_cursor with a scatter gather table
+ *
+ * @sg: scatter gather table to walk
+ * @start: Start of the range
+ * @size: Size of the range
+ * @cur: cursor object to initialize
+ *
+ * Start walking over the range of allocations between @start and @size.
+ */
+static inline void xe_res_first_sg(const struct sg_table *sg,
+				   u64 start, u64 size,
+				   struct xe_res_cursor *cur)
+{
+	XE_BUG_ON(!sg);
+	XE_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE) ||
+		  !IS_ALIGNED(size, PAGE_SIZE));
+	cur->node = NULL;
+	cur->start = start;
+	cur->remaining = size;
+	cur->size = 0;
+	cur->sgl = sg->sgl;
+	cur->mem_type = XE_PL_TT;
+	__xe_res_sg_next(cur);
+}
+
+/**
+ * xe_res_next - advance the cursor
+ *
+ * @cur: the cursor to advance
+ * @size: number of bytes to move forward
+ *
+ * Move the cursor @size bytes forwrad, walking to the next node if necessary.
+ */
+static inline void xe_res_next(struct xe_res_cursor *cur, u64 size)
+{
+	struct drm_buddy_block *block;
+	struct list_head *next;
+	u64 start;
+
+	XE_BUG_ON(size > cur->remaining);
+
+	cur->remaining -= size;
+	if (!cur->remaining)
+		return;
+
+	if (cur->size > size) {
+		cur->size -= size;
+		cur->start += size;
+		return;
+	}
+
+	if (cur->sgl) {
+		cur->start += size;
+		__xe_res_sg_next(cur);
+		return;
+	}
+
+	switch (cur->mem_type) {
+	case XE_PL_VRAM0:
+	case XE_PL_VRAM1:
+		start = size - cur->size;
+		block = cur->node;
+
+		next = block->link.next;
+		block = list_entry(next, struct drm_buddy_block, link);
+
+
+		while (start >= xe_ttm_vram_mgr_block_size(block)) {
+			start -= xe_ttm_vram_mgr_block_size(block);
+
+			next = block->link.next;
+			block = list_entry(next, struct drm_buddy_block, link);
+		}
+
+		cur->start = xe_ttm_vram_mgr_block_start(block) + start;
+		cur->size = min(xe_ttm_vram_mgr_block_size(block) - start,
+				cur->remaining);
+		cur->node = block;
+		break;
+	default:
+		return;
+	}
+}
+
+/**
+ * xe_res_dma - return dma address of cursor at current position
+ *
+ * @cur: the cursor to return the dma address from
+ */
+static inline u64 xe_res_dma(const struct xe_res_cursor *cur)
+{
+	return cur->sgl ? sg_dma_address(cur->sgl) + cur->start : cur->start;
+}
+#endif