LXR linux/drivers/staging/media/ipu3/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}
 101