ipu3-css-pool.c

  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}