media/ipu3/ipu3-css-pool.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 // Copyright (C) 2018 Intel Corporation
0003
0004 #include <linux/device.h>
0005
0006 #include "ipu3.h"
0007 #include "ipu3-css-pool.h"
0008 #include "ipu3-dmamap.h"
0009
0010 int imgu_css_dma_buffer_resize(struct imgu_device *imgu,
0011                    struct imgu_css_map *map, size_t size)
0012 {
0013     if (map->size < size && map->vaddr) {
0014         dev_warn(&imgu->pci_dev->dev, "dma buf resized from %zu to %zu",
0015              map->size, size);
0016
0017         imgu_dmamap_free(imgu, map);
0018         if (!imgu_dmamap_alloc(imgu, map, size))
0019             return -ENOMEM;
0020     }
0021
0022     return 0;
0023 }
0024
0025 void imgu_css_pool_cleanup(struct imgu_device *imgu, struct imgu_css_pool *pool)
0026 {
0027     unsigned int i;
0028
0029     for (i = 0; i < IPU3_CSS_POOL_SIZE; i++)
0030         imgu_dmamap_free(imgu, &pool->entry[i].param);
0031 }
0032
0033 int imgu_css_pool_init(struct imgu_device *imgu, struct imgu_css_pool *pool,
0034                size_t size)
0035 {
0036     unsigned int i;
0037
0038     for (i = 0; i < IPU3_CSS_POOL_SIZE; i++) {
0039         pool->entry[i].valid = false;
0040         if (size == 0) {
0041             pool->entry[i].param.vaddr = NULL;
0042             continue;
0043         }
0044
0045         if (!imgu_dmamap_alloc(imgu, &pool->entry[i].param, size))
0046             goto fail;
0047     }
0048
0049     pool->last = IPU3_CSS_POOL_SIZE;
0050
0051     return 0;
0052
0053 fail:
0054     imgu_css_pool_cleanup(imgu, pool);
0055     return -ENOMEM;
0056 }
0057
0058 /*
0059  * Allocate a new parameter via recycling the oldest entry in the pool.
0060  */
0061 void imgu_css_pool_get(struct imgu_css_pool *pool)
0062 {
0063     /* Get the oldest entry */
0064     u32 n = (pool->last + 1) % IPU3_CSS_POOL_SIZE;
0065
0066     pool->entry[n].valid = true;
0067     pool->last = n;
0068 }
0069
0070 /*
0071  * Undo, for all practical purposes, the effect of pool_get().
0072  */
0073 void imgu_css_pool_put(struct imgu_css_pool *pool)
0074 {
0075     pool->entry[pool->last].valid = false;
0076     pool->last = (pool->last + IPU3_CSS_POOL_SIZE - 1) % IPU3_CSS_POOL_SIZE;
0077 }
0078
0079 /**
0080  * imgu_css_pool_last - Retrieve the nth pool entry from last
0081  *
0082  * @pool: a pointer to &struct imgu_css_pool.
0083  * @n: the distance to the last index.
0084  *
0085  * Returns:
0086  *  The nth entry from last or null map to indicate no frame stored.
0087  */
0088 const struct imgu_css_map *
0089 imgu_css_pool_last(struct imgu_css_pool *pool, unsigned int n)
0090 {
0091     static const struct imgu_css_map null_map = { 0 };
0092     int i = (pool->last + IPU3_CSS_POOL_SIZE - n) % IPU3_CSS_POOL_SIZE;
0093
0094     WARN_ON(n >= IPU3_CSS_POOL_SIZE);
0095
0096     if (!pool->entry[i].valid)
0097         return &null_map;
0098
0099     return &pool->entry[i].param;
0100 }