1/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
  2/*
  3 * Copyright 2020 Advanced Micro Devices, Inc.
  4 *
  5 * Permission is hereby granted, free of charge, to any person obtaining a
  6 * copy of this software and associated documentation files (the "Software"),
  7 * to deal in the Software without restriction, including without limitation
  8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  9 * and/or sell copies of the Software, and to permit persons to whom the
 10 * Software is furnished to do so, subject to the following conditions:
 11 *
 12 * The above copyright notice and this permission notice shall be included in
 13 * all copies or substantial portions of the Software.
 14 *
 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 21 * OTHER DEALINGS IN THE SOFTWARE.
 22 */
 23
 24#ifndef _XE_RES_CURSOR_H_
 25#define _XE_RES_CURSOR_H_
 26
 27#include <linux/scatterlist.h>
 28
 29#include <drm/ttm/ttm_placement.h>
 30#include <drm/ttm/ttm_range_manager.h>
 31#include <drm/ttm/ttm_resource.h>
 32#include <drm/ttm/ttm_tt.h>
 33
 34#include "xe_bo.h"
 35#include "xe_device.h"
 36#include "xe_macros.h"
 37#include "xe_ttm_vram_mgr.h"
 38
 39/* state back for walking over vram_mgr, stolen_mgr, and gtt_mgr allocations */
 40struct xe_res_cursor {
 41	u64 start;
 42	u64 size;
 43	u64 remaining;
 44	void *node;
 45	u32 mem_type;
 46	struct scatterlist *sgl;
 47	struct drm_buddy *mm;
 48};
 49
 50static struct drm_buddy *xe_res_get_buddy(struct ttm_resource *res)
 51{
 52	struct ttm_resource_manager *mgr;
 53
 54	mgr = ttm_manager_type(res->bo->bdev, res->mem_type);
 55	return &to_xe_ttm_vram_mgr(mgr)->mm;
 56}
 57
 58/**
 59 * xe_res_first - initialize a xe_res_cursor
 60 *
 61 * @res: TTM resource object to walk
 62 * @start: Start of the range
 63 * @size: Size of the range
 64 * @cur: cursor object to initialize
 65 *
 66 * Start walking over the range of allocations between @start and @size.
 67 */
 68static inline void xe_res_first(struct ttm_resource *res,
 69				u64 start, u64 size,
 70				struct xe_res_cursor *cur)
 71{
 72	cur->sgl = NULL;
 73	if (!res)
 74		goto fallback;
 75
 76	XE_WARN_ON(start + size > res->size);
 77
 78	cur->mem_type = res->mem_type;
 79
 80	switch (cur->mem_type) {
 81	case XE_PL_STOLEN:
 82	case XE_PL_VRAM0:
 83	case XE_PL_VRAM1: {
 84		struct drm_buddy_block *block;
 85		struct list_head *head, *next;
 86		struct drm_buddy *mm = xe_res_get_buddy(res);
 87
 88		head = &to_xe_ttm_vram_mgr_resource(res)->blocks;
 89
 90		block = list_first_entry_or_null(head,
 91						 struct drm_buddy_block,
 92						 link);
 93		if (!block)
 94			goto fallback;
 95
 96		while (start >= drm_buddy_block_size(mm, block)) {
 97			start -= drm_buddy_block_size(mm, block);
 98
 99			next = block->link.next;
100			if (next != head)
101				block = list_entry(next, struct drm_buddy_block,
102						   link);
103		}
104
105		cur->mm = mm;
106		cur->start = drm_buddy_block_offset(block) + start;
107		cur->size = min(drm_buddy_block_size(mm, block) - start,
108				size);
109		cur->remaining = size;
110		cur->node = block;
111		break;
112	}
113	default:
114		goto fallback;
115	}
116
117	return;
118
119fallback:
120	cur->start = start;
121	cur->size = size;
122	cur->remaining = size;
123	cur->node = NULL;
124	cur->mem_type = XE_PL_TT;
125	XE_WARN_ON(res && start + size > res->size);
126}
127
128static inline void __xe_res_sg_next(struct xe_res_cursor *cur)
129{
130	struct scatterlist *sgl = cur->sgl;
131	u64 start = cur->start;
132
133	while (start >= sg_dma_len(sgl)) {
134		start -= sg_dma_len(sgl);
135		sgl = sg_next(sgl);
136		XE_WARN_ON(!sgl);
137	}
138
139	cur->start = start;
140	cur->size = sg_dma_len(sgl) - start;
141	cur->sgl = sgl;
142}
143
144/**
145 * xe_res_first_sg - initialize a xe_res_cursor with a scatter gather table
146 *
147 * @sg: scatter gather table to walk
148 * @start: Start of the range
149 * @size: Size of the range
150 * @cur: cursor object to initialize
151 *
152 * Start walking over the range of allocations between @start and @size.
153 */
154static inline void xe_res_first_sg(const struct sg_table *sg,
155				   u64 start, u64 size,
156				   struct xe_res_cursor *cur)
157{
158	XE_WARN_ON(!sg);
159	cur->node = NULL;
160	cur->start = start;
161	cur->remaining = size;
162	cur->size = 0;
163	cur->sgl = sg->sgl;
164	cur->mem_type = XE_PL_TT;
165	__xe_res_sg_next(cur);
166}
167
168/**
169 * xe_res_next - advance the cursor
170 *
171 * @cur: the cursor to advance
172 * @size: number of bytes to move forward
173 *
174 * Move the cursor @size bytes forwrad, walking to the next node if necessary.
175 */
176static inline void xe_res_next(struct xe_res_cursor *cur, u64 size)
177{
178	struct drm_buddy_block *block;
179	struct list_head *next;
180	u64 start;
181
182	XE_WARN_ON(size > cur->remaining);
183
184	cur->remaining -= size;
185	if (!cur->remaining)
186		return;
187
188	if (cur->size > size) {
189		cur->size -= size;
190		cur->start += size;
191		return;
192	}
193
194	if (cur->sgl) {
195		cur->start += size;
196		__xe_res_sg_next(cur);
197		return;
198	}
199
200	switch (cur->mem_type) {
201	case XE_PL_STOLEN:
202	case XE_PL_VRAM0:
203	case XE_PL_VRAM1:
204		start = size - cur->size;
205		block = cur->node;
206
207		next = block->link.next;
208		block = list_entry(next, struct drm_buddy_block, link);
209
210
211		while (start >= drm_buddy_block_size(cur->mm, block)) {
212			start -= drm_buddy_block_size(cur->mm, block);
213
214			next = block->link.next;
215			block = list_entry(next, struct drm_buddy_block, link);
216		}
217
218		cur->start = drm_buddy_block_offset(block) + start;
219		cur->size = min(drm_buddy_block_size(cur->mm, block) - start,
220				cur->remaining);
221		cur->node = block;
222		break;
223	default:
224		return;
225	}
226}
227
228/**
229 * xe_res_dma - return dma address of cursor at current position
230 *
231 * @cur: the cursor to return the dma address from
232 */
233static inline u64 xe_res_dma(const struct xe_res_cursor *cur)
234{
235	return cur->sgl ? sg_dma_address(cur->sgl) + cur->start : cur->start;
236}
237#endif