diff --git a/drivers/staging/media/ipu3/ipu3-css-pool.c b/drivers/staging/media/ipu3/ipu3-css-pool.c new file mode 100644 index 000000000000..6f271f81669b --- /dev/null +++ b/drivers/staging/media/ipu3/ipu3-css-pool.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Intel Corporation + +#include + +#include "ipu3.h" +#include "ipu3-css-pool.h" +#include "ipu3-dmamap.h" + +int ipu3_css_dma_buffer_resize(struct imgu_device *imgu, + struct ipu3_css_map *map, size_t size) +{ + if (map->size < size && map->vaddr) { + dev_warn(&imgu->pci_dev->dev, "dma buf resized from %zu to %zu", + map->size, size); + + ipu3_dmamap_free(imgu, map); + if (!ipu3_dmamap_alloc(imgu, map, size)) + return -ENOMEM; + } + + return 0; +} + +void ipu3_css_pool_cleanup(struct imgu_device *imgu, struct ipu3_css_pool *pool) +{ + unsigned int i; + + for (i = 0; i < IPU3_CSS_POOL_SIZE; i++) + ipu3_dmamap_free(imgu, &pool->entry[i].param); +} + +int ipu3_css_pool_init(struct imgu_device *imgu, struct ipu3_css_pool *pool, + size_t size) +{ + unsigned int i; + + for (i = 0; i < IPU3_CSS_POOL_SIZE; i++) { + pool->entry[i].valid = false; + if (size == 0) { + pool->entry[i].param.vaddr = NULL; + continue; + } + + if (!ipu3_dmamap_alloc(imgu, &pool->entry[i].param, size)) + goto fail; + } + + pool->last = IPU3_CSS_POOL_SIZE; + + return 0; + +fail: + ipu3_css_pool_cleanup(imgu, pool); + return -ENOMEM; +} + +/* + * Allocate a new parameter via recycling the oldest entry in the pool. + */ +void ipu3_css_pool_get(struct ipu3_css_pool *pool) +{ + /* Get the oldest entry */ + u32 n = (pool->last + 1) % IPU3_CSS_POOL_SIZE; + + pool->entry[n].valid = true; + pool->last = n; +} + +/* + * Undo, for all practical purposes, the effect of pool_get(). + */ +void ipu3_css_pool_put(struct ipu3_css_pool *pool) +{ + pool->entry[pool->last].valid = false; + pool->last = (pool->last + IPU3_CSS_POOL_SIZE - 1) % IPU3_CSS_POOL_SIZE; +} + +/** + * ipu3_css_pool_last - Retrieve the nth pool entry from last + * + * @pool: a pointer to &struct ipu3_css_pool. + * @n: the distance to the last index. + * + * Returns: + * The nth entry from last or null map to indicate no frame stored. + */ +const struct ipu3_css_map * +ipu3_css_pool_last(struct ipu3_css_pool *pool, unsigned int n) +{ + static const struct ipu3_css_map null_map = { 0 }; + int i = (pool->last + IPU3_CSS_POOL_SIZE - n) % IPU3_CSS_POOL_SIZE; + + WARN_ON(n >= IPU3_CSS_POOL_SIZE); + + if (!pool->entry[i].valid) + return &null_map; + + return &pool->entry[i].param; +} diff --git a/drivers/staging/media/ipu3/ipu3-css-pool.h b/drivers/staging/media/ipu3/ipu3-css-pool.h new file mode 100644 index 000000000000..2657c39a4d71 --- /dev/null +++ b/drivers/staging/media/ipu3/ipu3-css-pool.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2018 Intel Corporation */ + +#ifndef __IPU3_UTIL_H +#define __IPU3_UTIL_H + +struct device; +struct imgu_device; + +#define IPU3_CSS_POOL_SIZE 4 + +/** + * ipu3_css_map - store DMA mapping info for buffer + * + * @size: size of the buffer in bytes. + * @vaddr: kernel virtual address. + * @daddr: iova dma address to access IPU3. + * @vma: private, a pointer to &struct vm_struct, + * used for ipu3_dmamap_free. + */ +struct ipu3_css_map { + size_t size; + void *vaddr; + dma_addr_t daddr; + struct vm_struct *vma; +}; + +/** + * ipu3_css_pool - circular buffer pool definition + * + * @entry: array with IPU3_CSS_POOL_SIZE elements. + * @entry.param: a &struct ipu3_css_map for storing the mem mapping. + * @entry.valid: used to mark if the entry has valid data. + * @last: write pointer, initialized to IPU3_CSS_POOL_SIZE. + */ +struct ipu3_css_pool { + struct { + struct ipu3_css_map param; + bool valid; + } entry[IPU3_CSS_POOL_SIZE]; + u32 last; +}; + +int ipu3_css_dma_buffer_resize(struct imgu_device *imgu, + struct ipu3_css_map *map, size_t size); +void ipu3_css_pool_cleanup(struct imgu_device *imgu, + struct ipu3_css_pool *pool); +int ipu3_css_pool_init(struct imgu_device *imgu, struct ipu3_css_pool *pool, + size_t size); +void ipu3_css_pool_get(struct ipu3_css_pool *pool); +void ipu3_css_pool_put(struct ipu3_css_pool *pool); +const struct ipu3_css_map *ipu3_css_pool_last(struct ipu3_css_pool *pool, + u32 last); + +#endif