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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/staging/media/atomisp/pci/base/circbuf/src | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/staging/media/atomisp/pci/base/circbuf/src')
-rw-r--r-- | drivers/staging/media/atomisp/pci/base/circbuf/src/circbuf.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/drivers/staging/media/atomisp/pci/base/circbuf/src/circbuf.c b/drivers/staging/media/atomisp/pci/base/circbuf/src/circbuf.c new file mode 100644 index 0000000000..d9f7c14379 --- /dev/null +++ b/drivers/staging/media/atomisp/pci/base/circbuf/src/circbuf.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for Intel Camera Imaging ISP subsystem. + * Copyright (c) 2015, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include "ia_css_circbuf.h" + +#include <assert_support.h> + +/********************************************************************** + * + * Forward declarations. + * + **********************************************************************/ +/* + * @brief Read the oldest element from the circular buffer. + * Read the oldest element WITHOUT checking whehter the + * circular buffer is empty or not. The oldest element is + * also removed out from the circular buffer. + * + * @param cb The pointer to the circular buffer. + * + * @return the oldest element. + */ +static inline ia_css_circbuf_elem_t +ia_css_circbuf_read(ia_css_circbuf_t *cb); + +/* + * @brief Shift a chunk of elements in the circular buffer. + * A chunk of elements (i.e. the ones from the "start" position + * to the "chunk_src" position) are shifted in the circular buffer, + * along the direction of new elements coming. + * + * @param cb The pointer to the circular buffer. + * @param chunk_src The position at which the first element in the chunk is. + * @param chunk_dest The position to which the first element in the chunk would be shift. + */ +static inline void ia_css_circbuf_shift_chunk(ia_css_circbuf_t *cb, + u32 chunk_src, + uint32_t chunk_dest); + +/* + * @brief Get the "val" field in the element. + * + * @param elem The pointer to the element. + * + * @return the "val" field. + */ +static inline uint32_t +ia_css_circbuf_elem_get_val(ia_css_circbuf_elem_t *elem); + +/********************************************************************** + * + * Non-inline functions. + * + **********************************************************************/ +/* + * @brief Create the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +void +ia_css_circbuf_create(ia_css_circbuf_t *cb, + ia_css_circbuf_elem_t *elems, + ia_css_circbuf_desc_t *desc) +{ + u32 i; + + OP___assert(desc); + + cb->desc = desc; + /* Initialize to defaults */ + cb->desc->start = 0; + cb->desc->end = 0; + cb->desc->step = 0; + + for (i = 0; i < cb->desc->size; i++) + ia_css_circbuf_elem_init(&elems[i]); + + cb->elems = elems; +} + +/* + * @brief Destroy the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +void ia_css_circbuf_destroy(ia_css_circbuf_t *cb) +{ + cb->desc = NULL; + + cb->elems = NULL; +} + +/* + * @brief Pop a value out of the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +uint32_t ia_css_circbuf_pop(ia_css_circbuf_t *cb) +{ + u32 ret; + ia_css_circbuf_elem_t elem; + + assert(!ia_css_circbuf_is_empty(cb)); + + /* read an element from the buffer */ + elem = ia_css_circbuf_read(cb); + ret = ia_css_circbuf_elem_get_val(&elem); + return ret; +} + +/* + * @brief Extract a value out of the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +uint32_t ia_css_circbuf_extract(ia_css_circbuf_t *cb, int offset) +{ + int max_offset; + u32 val; + u32 pos; + u32 src_pos; + u32 dest_pos; + + /* get the maximum offest */ + max_offset = ia_css_circbuf_get_offset(cb, cb->desc->start, cb->desc->end); + max_offset--; + + /* + * Step 1: When the target element is at the "start" position. + */ + if (offset == 0) { + val = ia_css_circbuf_pop(cb); + return val; + } + + /* + * Step 2: When the target element is out of the range. + */ + if (offset > max_offset) { + val = 0; + return val; + } + + /* + * Step 3: When the target element is between the "start" and + * "end" position. + */ + /* get the position of the target element */ + pos = ia_css_circbuf_get_pos_at_offset(cb, cb->desc->start, offset); + + /* get the value from the target element */ + val = ia_css_circbuf_elem_get_val(&cb->elems[pos]); + + /* shift the elements */ + src_pos = ia_css_circbuf_get_pos_at_offset(cb, pos, -1); + dest_pos = pos; + ia_css_circbuf_shift_chunk(cb, src_pos, dest_pos); + + return val; +} + +/* + * @brief Peek an element from the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +uint32_t ia_css_circbuf_peek(ia_css_circbuf_t *cb, int offset) +{ + int pos; + + pos = ia_css_circbuf_get_pos_at_offset(cb, cb->desc->end, offset); + + /* get the value at the position */ + return cb->elems[pos].val; +} + +/* + * @brief Get the value of an element from the circular buffer. + * Refer to "ia_css_circbuf.h" for details. + */ +uint32_t ia_css_circbuf_peek_from_start(ia_css_circbuf_t *cb, int offset) +{ + int pos; + + pos = ia_css_circbuf_get_pos_at_offset(cb, cb->desc->start, offset); + + /* get the value at the position */ + return cb->elems[pos].val; +} + +/* @brief increase size of a circular buffer. + * Use 'CAUTION' before using this function. This was added to + * support / fix issue with increasing size for tagger only + * Please refer to "ia_css_circbuf.h" for details. + */ +bool ia_css_circbuf_increase_size( + ia_css_circbuf_t *cb, + unsigned int sz_delta, + ia_css_circbuf_elem_t *elems) +{ + u8 curr_size; + u8 curr_end; + unsigned int i = 0; + + if (!cb || sz_delta == 0) + return false; + + curr_size = cb->desc->size; + curr_end = cb->desc->end; + /* We assume cb was pre defined as global to allow + * increase in size */ + /* FM: are we sure this cannot cause size to become too big? */ + if (((uint8_t)(cb->desc->size + (uint8_t)sz_delta) > cb->desc->size) && + ((uint8_t)sz_delta == sz_delta)) + cb->desc->size += (uint8_t)sz_delta; + else + return false; /* overflow in size */ + + /* If elems are passed update them else we assume its been taken + * care before calling this function */ + if (elems) { + /* cb element array size will not be increased dynamically, + * but pointers to new elements can be added at the end + * of existing pre defined cb element array of + * size >= new size if not already added */ + for (i = curr_size; i < cb->desc->size; i++) + cb->elems[i] = elems[i - curr_size]; + } + /* Fix Start / End */ + if (curr_end < cb->desc->start) { + if (curr_end == 0) { + /* Easily fix End */ + cb->desc->end = curr_size; + } else { + /* Move elements and fix Start*/ + ia_css_circbuf_shift_chunk(cb, + curr_size - 1, + curr_size + sz_delta - 1); + } + } + + return true; +} + +/**************************************************************** + * + * Inline functions. + * + ****************************************************************/ +/* + * @brief Get the "val" field in the element. + * Refer to "Forward declarations" for details. + */ +static inline uint32_t +ia_css_circbuf_elem_get_val(ia_css_circbuf_elem_t *elem) +{ + return elem->val; +} + +/* + * @brief Read the oldest element from the circular buffer. + * Refer to "Forward declarations" for details. + */ +static inline ia_css_circbuf_elem_t +ia_css_circbuf_read(ia_css_circbuf_t *cb) +{ + ia_css_circbuf_elem_t elem; + + /* get the element from the target position */ + elem = cb->elems[cb->desc->start]; + + /* clear the target position */ + ia_css_circbuf_elem_init(&cb->elems[cb->desc->start]); + + /* adjust the "start" position */ + cb->desc->start = ia_css_circbuf_get_pos_at_offset(cb, cb->desc->start, 1); + return elem; +} + +/* + * @brief Shift a chunk of elements in the circular buffer. + * Refer to "Forward declarations" for details. + */ +static inline void +ia_css_circbuf_shift_chunk(ia_css_circbuf_t *cb, + u32 chunk_src, uint32_t chunk_dest) +{ + int chunk_offset; + int chunk_sz; + int i; + + /* get the chunk offset and size */ + chunk_offset = ia_css_circbuf_get_offset(cb, + chunk_src, chunk_dest); + chunk_sz = ia_css_circbuf_get_offset(cb, cb->desc->start, chunk_src) + 1; + + /* shift each element to its terminal position */ + for (i = 0; i < chunk_sz; i++) { + /* copy the element from the source to the destination */ + ia_css_circbuf_elem_cpy(&cb->elems[chunk_src], + &cb->elems[chunk_dest]); + + /* clear the source position */ + ia_css_circbuf_elem_init(&cb->elems[chunk_src]); + + /* adjust the source/terminal positions */ + chunk_src = ia_css_circbuf_get_pos_at_offset(cb, chunk_src, -1); + chunk_dest = ia_css_circbuf_get_pos_at_offset(cb, chunk_dest, -1); + } + + /* adjust the index "start" */ + cb->desc->start = ia_css_circbuf_get_pos_at_offset(cb, cb->desc->start, + chunk_offset); +} |