1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2018 Intel Corporation
3
4#include <linux/device.h>
5
6#include "ipu3.h"
7#include "ipu3-css-pool.h"
8#include "ipu3-dmamap.h"
9
10int imgu_css_dma_buffer_resize(struct imgu_device *imgu,
11			       struct imgu_css_map *map, size_t size)
12{
13	if (map->size < size && map->vaddr) {
14		dev_warn(&imgu->pci_dev->dev, "dma buf resized from %zu to %zu",
15			 map->size, size);
16
17		imgu_dmamap_free(imgu, map);
18		if (!imgu_dmamap_alloc(imgu, map, size))
19			return -ENOMEM;
20	}
21
22	return 0;
23}
24
25void imgu_css_pool_cleanup(struct imgu_device *imgu, struct imgu_css_pool *pool)
26{
27	unsigned int i;
28
29	for (i = 0; i < IPU3_CSS_POOL_SIZE; i++)
30		imgu_dmamap_free(imgu, &pool->entry[i].param);
31}
32
33int imgu_css_pool_init(struct imgu_device *imgu, struct imgu_css_pool *pool,
34		       size_t size)
35{
36	unsigned int i;
37
38	for (i = 0; i < IPU3_CSS_POOL_SIZE; i++) {
39		pool->entry[i].valid = false;
40		if (size == 0) {
41			pool->entry[i].param.vaddr = NULL;
42			continue;
43		}
44
45		if (!imgu_dmamap_alloc(imgu, &pool->entry[i].param, size))
46			goto fail;
47	}
48
49	pool->last = IPU3_CSS_POOL_SIZE;
50
51	return 0;
52
53fail:
54	imgu_css_pool_cleanup(imgu, pool);
55	return -ENOMEM;
56}
57
58/*
59 * Allocate a new parameter via recycling the oldest entry in the pool.
60 */
61void imgu_css_pool_get(struct imgu_css_pool *pool)
62{
63	/* Get the oldest entry */
64	u32 n = (pool->last + 1) % IPU3_CSS_POOL_SIZE;
65
66	pool->entry[n].valid = true;
67	pool->last = n;
68}
69
70/*
71 * Undo, for all practical purposes, the effect of pool_get().
72 */
73void imgu_css_pool_put(struct imgu_css_pool *pool)
74{
75	pool->entry[pool->last].valid = false;
76	pool->last = (pool->last + IPU3_CSS_POOL_SIZE - 1) % IPU3_CSS_POOL_SIZE;
77}
78
79/**
80 * imgu_css_pool_last - Retrieve the nth pool entry from last
81 *
82 * @pool: a pointer to &struct imgu_css_pool.
83 * @n: the distance to the last index.
84 *
85 * Returns:
86 *  The nth entry from last or null map to indicate no frame stored.
87 */
88const struct imgu_css_map *
89imgu_css_pool_last(struct imgu_css_pool *pool, unsigned int n)
90{
91	static const struct imgu_css_map null_map = { 0 };
92	int i = (pool->last + IPU3_CSS_POOL_SIZE - n) % IPU3_CSS_POOL_SIZE;
93
94	WARN_ON(n >= IPU3_CSS_POOL_SIZE);
95
96	if (!pool->entry[i].valid)
97		return &null_map;
98
99	return &pool->entry[i].param;
100}
101