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/drm_mm.h>
 30#include <drm/ttm/ttm_placement.h>
 31#include <drm/ttm/ttm_range_manager.h>
 32#include <drm/ttm/ttm_resource.h>
 33#include <drm/ttm/ttm_tt.h>
 34
 35#include "xe_bo.h"
 36#include "xe_device.h"
 37#include "xe_macros.h"
 38#include "xe_ttm_vram_mgr.h"
 39
 40/* state back for walking over vram_mgr, stolen_mgr, and gtt_mgr allocations */
 41struct xe_res_cursor {
 42	u64 start;
 43	u64 size;
 44	u64 remaining;
 45	void *node;
 46	u32 mem_type;
 47	struct scatterlist *sgl;
 48	struct drm_buddy *mm;
 49};
 50
 51static struct drm_buddy *xe_res_get_buddy(struct ttm_resource *res)
 52{
 53	struct ttm_resource_manager *mgr;
 54
 55	mgr = ttm_manager_type(res->bo->bdev, res->mem_type);
 56	return &to_xe_ttm_vram_mgr(mgr)->mm;
 57}
 58
 59/**
 60 * xe_res_first - initialize a xe_res_cursor
 61 *
 62 * @res: TTM resource object to walk
 63 * @start: Start of the range
 64 * @size: Size of the range
 65 * @cur: cursor object to initialize
 66 *
 67 * Start walking over the range of allocations between @start and @size.
 68 */
 69static inline void xe_res_first(struct ttm_resource *res,
 70				u64 start, u64 size,
 71				struct xe_res_cursor *cur)
 72{
 73	cur->sgl = NULL;
 74	if (!res)
 75		goto fallback;
 76
 77	XE_WARN_ON(start + size > res->size);
 78
 79	cur->mem_type = res->mem_type;
 80
 81	switch (cur->mem_type) {
 82	case XE_PL_STOLEN:
 83	case XE_PL_VRAM0:
 84	case XE_PL_VRAM1: {
 85		struct drm_buddy_block *block;
 86		struct list_head *head, *next;
 87		struct drm_buddy *mm = xe_res_get_buddy(res);
 88
 89		head = &to_xe_ttm_vram_mgr_resource(res)->blocks;
 90
 91		block = list_first_entry_or_null(head,
 92						 struct drm_buddy_block,
 93						 link);
 94		if (!block)
 95			goto fallback;
 96
 97		while (start >= drm_buddy_block_size(mm, block)) {
 98			start -= drm_buddy_block_size(mm, block);
 99
100			next = block->link.next;
101			if (next != head)
102				block = list_entry(next, struct drm_buddy_block,
103						   link);
104		}
105
106		cur->mm = mm;
107		cur->start = drm_buddy_block_offset(block) + start;
108		cur->size = min(drm_buddy_block_size(mm, block) - start,
109				size);
110		cur->remaining = size;
111		cur->node = block;
112		break;
113	}
114	default:
115		goto fallback;
116	}
117
118	return;
119
120fallback:
121	cur->start = start;
122	cur->size = size;
123	cur->remaining = size;
124	cur->node = NULL;
125	cur->mem_type = XE_PL_TT;
126	XE_WARN_ON(res && start + size > res->size);
127}
128
129static inline void __xe_res_sg_next(struct xe_res_cursor *cur)
130{
131	struct scatterlist *sgl = cur->sgl;
132	u64 start = cur->start;
133
134	while (start >= sg_dma_len(sgl)) {
135		start -= sg_dma_len(sgl);
136		sgl = sg_next(sgl);
137		XE_WARN_ON(!sgl);
138	}
139
140	cur->start = start;
141	cur->size = sg_dma_len(sgl) - start;
142	cur->sgl = sgl;
143}
144
145/**
146 * xe_res_first_sg - initialize a xe_res_cursor with a scatter gather table
147 *
148 * @sg: scatter gather table to walk
149 * @start: Start of the range
150 * @size: Size of the range
151 * @cur: cursor object to initialize
152 *
153 * Start walking over the range of allocations between @start and @size.
154 */
155static inline void xe_res_first_sg(const struct sg_table *sg,
156				   u64 start, u64 size,
157				   struct xe_res_cursor *cur)
158{
159	XE_WARN_ON(!sg);
160	XE_WARN_ON(!IS_ALIGNED(start, PAGE_SIZE) ||
161		   !IS_ALIGNED(size, PAGE_SIZE));
162	cur->node = NULL;
163	cur->start = start;
164	cur->remaining = size;
165	cur->size = 0;
166	cur->sgl = sg->sgl;
167	cur->mem_type = XE_PL_TT;
168	__xe_res_sg_next(cur);
169}
170
171/**
172 * xe_res_next - advance the cursor
173 *
174 * @cur: the cursor to advance
175 * @size: number of bytes to move forward
176 *
177 * Move the cursor @size bytes forwrad, walking to the next node if necessary.
178 */
179static inline void xe_res_next(struct xe_res_cursor *cur, u64 size)
180{
181	struct drm_buddy_block *block;
182	struct list_head *next;
183	u64 start;
184
185	XE_WARN_ON(size > cur->remaining);
186
187	cur->remaining -= size;
188	if (!cur->remaining)
189		return;
190
191	if (cur->size > size) {
192		cur->size -= size;
193		cur->start += size;
194		return;
195	}
196
197	if (cur->sgl) {
198		cur->start += size;
199		__xe_res_sg_next(cur);
200		return;
201	}
202
203	switch (cur->mem_type) {
204	case XE_PL_STOLEN:
205	case XE_PL_VRAM0:
206	case XE_PL_VRAM1:
207		start = size - cur->size;
208		block = cur->node;
209
210		next = block->link.next;
211		block = list_entry(next, struct drm_buddy_block, link);
212
213
214		while (start >= drm_buddy_block_size(cur->mm, block)) {
215			start -= drm_buddy_block_size(cur->mm, block);
216
217			next = block->link.next;
218			block = list_entry(next, struct drm_buddy_block, link);
219		}
220
221		cur->start = drm_buddy_block_offset(block) + start;
222		cur->size = min(drm_buddy_block_size(cur->mm, block) - start,
223				cur->remaining);
224		cur->node = block;
225		break;
226	default:
227		return;
228	}
229}
230
231/**
232 * xe_res_dma - return dma address of cursor at current position
233 *
234 * @cur: the cursor to return the dma address from
235 */
236static inline u64 xe_res_dma(const struct xe_res_cursor *cur)
237{
238	return cur->sgl ? sg_dma_address(cur->sgl) + cur->start : cur->start;
239}
240#endif