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Diffstat (limited to 'tinyusb/src/common/tusb_fifo.c')
| -rwxr-xr-x | tinyusb/src/common/tusb_fifo.c | 1000 |
1 files changed, 1000 insertions, 0 deletions
diff --git a/tinyusb/src/common/tusb_fifo.c b/tinyusb/src/common/tusb_fifo.c new file mode 100755 index 00000000..11b8fc5f --- /dev/null +++ b/tinyusb/src/common/tusb_fifo.c @@ -0,0 +1,1000 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2019 Ha Thach (tinyusb.org) + * Copyright (c) 2020 Reinhard Panhuber - rework to unmasked pointers + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * + * This file is part of the TinyUSB stack. + */ + +#include "osal/osal.h" +#include "tusb_fifo.h" + +// Supress IAR warning +// Warning[Pa082]: undefined behavior: the order of volatile accesses is undefined in this statement +#if defined(__ICCARM__) +#pragma diag_suppress = Pa082 +#endif + +// implement mutex lock and unlock +#if CFG_FIFO_MUTEX + +static inline void _ff_lock(tu_fifo_mutex_t mutex) +{ + if (mutex) osal_mutex_lock(mutex, OSAL_TIMEOUT_WAIT_FOREVER); +} + +static inline void _ff_unlock(tu_fifo_mutex_t mutex) +{ + if (mutex) osal_mutex_unlock(mutex); +} + +#else + +#define _ff_lock(_mutex) +#define _ff_unlock(_mutex) + +#endif + +/** \enum tu_fifo_copy_mode_t + * \brief Write modes intended to allow special read and write functions to be able to + * copy data to and from USB hardware FIFOs as needed for e.g. STM32s and others + */ +typedef enum +{ + TU_FIFO_COPY_INC, ///< Copy from/to an increasing source/destination address - default mode + TU_FIFO_COPY_CST_FULL_WORDS, ///< Copy from/to a constant source/destination address - required for e.g. STM32 to write into USB hardware FIFO +} tu_fifo_copy_mode_t; + +bool tu_fifo_config(tu_fifo_t *f, void* buffer, uint16_t depth, uint16_t item_size, bool overwritable) +{ + if (depth > 0x8000) return false; // Maximum depth is 2^15 items + + _ff_lock(f->mutex_wr); + _ff_lock(f->mutex_rd); + + f->buffer = (uint8_t*) buffer; + f->depth = depth; + f->item_size = item_size; + f->overwritable = overwritable; + + // Limit index space to 2*depth - this allows for a fast "modulo" calculation + // but limits the maximum depth to 2^16/2 = 2^15 and buffer overflows are detectable + // only if overflow happens once (important for unsupervised DMA applications) + f->max_pointer_idx = 2*depth - 1; + f->non_used_index_space = UINT16_MAX - f->max_pointer_idx; + + f->rd_idx = f->wr_idx = 0; + + _ff_unlock(f->mutex_wr); + _ff_unlock(f->mutex_rd); + + return true; +} + +// Static functions are intended to work on local variables +static inline uint16_t _ff_mod(uint16_t idx, uint16_t depth) +{ + while ( idx >= depth) idx -= depth; + return idx; +} + +// Intended to be used to read from hardware USB FIFO in e.g. STM32 where all data is read from a constant address +// Code adapted from dcd_synopsis.c +// TODO generalize with configurable 1 byte or 4 byte each read +static void _ff_push_const_addr(uint8_t * ff_buf, const void * app_buf, uint16_t len) +{ + volatile uint32_t * rx_fifo = (volatile uint32_t *) app_buf; + + // Reading full available 32 bit words from const app address + uint16_t full_words = len >> 2; + while(full_words--) + { + tu_unaligned_write32(ff_buf, *rx_fifo); + ff_buf += 4; + } + + // Read the remaining 1-3 bytes from const app address + uint8_t const bytes_rem = len & 0x03; + if ( bytes_rem ) + { + uint32_t tmp32 = *rx_fifo; + memcpy(ff_buf, &tmp32, bytes_rem); + } +} + +// Intended to be used to write to hardware USB FIFO in e.g. STM32 +// where all data is written to a constant address in full word copies +static void _ff_pull_const_addr(void * app_buf, const uint8_t * ff_buf, uint16_t len) +{ + volatile uint32_t * tx_fifo = (volatile uint32_t *) app_buf; + + // Pushing full available 32 bit words to const app address + uint16_t full_words = len >> 2; + while(full_words--) + { + *tx_fifo = tu_unaligned_read32(ff_buf); + ff_buf += 4; + } + + // Write the remaining 1-3 bytes into const app address + uint8_t const bytes_rem = len & 0x03; + if ( bytes_rem ) + { + uint32_t tmp32 = 0; + memcpy(&tmp32, ff_buf, bytes_rem); + + *tx_fifo = tmp32; + } +} + +// send one item to FIFO WITHOUT updating write pointer +static inline void _ff_push(tu_fifo_t* f, void const * app_buf, uint16_t rel) +{ + memcpy(f->buffer + (rel * f->item_size), app_buf, f->item_size); +} + +// send n items to FIFO WITHOUT updating write pointer +static void _ff_push_n(tu_fifo_t* f, void const * app_buf, uint16_t n, uint16_t rel, tu_fifo_copy_mode_t copy_mode) +{ + uint16_t const nLin = f->depth - rel; + uint16_t const nWrap = n - nLin; + + uint16_t nLin_bytes = nLin * f->item_size; + uint16_t nWrap_bytes = nWrap * f->item_size; + + // current buffer of fifo + uint8_t* ff_buf = f->buffer + (rel * f->item_size); + + switch (copy_mode) + { + case TU_FIFO_COPY_INC: + if(n <= nLin) + { + // Linear only + memcpy(ff_buf, app_buf, n*f->item_size); + } + else + { + // Wrap around + + // Write data to linear part of buffer + memcpy(ff_buf, app_buf, nLin_bytes); + + // Write data wrapped around + memcpy(f->buffer, ((uint8_t const*) app_buf) + nLin_bytes, nWrap_bytes); + } + break; + + case TU_FIFO_COPY_CST_FULL_WORDS: + // Intended for hardware buffers from which it can be read word by word only + if(n <= nLin) + { + // Linear only + _ff_push_const_addr(ff_buf, app_buf, n*f->item_size); + } + else + { + // Wrap around case + + // Write full words to linear part of buffer + uint16_t nLin_4n_bytes = nLin_bytes & 0xFFFC; + _ff_push_const_addr(ff_buf, app_buf, nLin_4n_bytes); + ff_buf += nLin_4n_bytes; + + // There could be odd 1-3 bytes before the wrap-around boundary + volatile uint32_t * rx_fifo = (volatile uint32_t *) app_buf; + uint8_t rem = nLin_bytes & 0x03; + if (rem > 0) + { + uint8_t remrem = tu_min16(nWrap_bytes, 4-rem); + nWrap_bytes -= remrem; + + uint32_t tmp32 = *rx_fifo; + uint8_t * src_u8 = ((uint8_t *) &tmp32); + + // Write 1-3 bytes before wrapped boundary + while(rem--) *ff_buf++ = *src_u8++; + + // Read more bytes to beginning to complete a word + ff_buf = f->buffer; + while(remrem--) *ff_buf++ = *src_u8++; + } + else + { + ff_buf = f->buffer; // wrap around to beginning + } + + // Write data wrapped part + if (nWrap_bytes > 0) _ff_push_const_addr(ff_buf, app_buf, nWrap_bytes); + } + break; + } +} + +// get one item from FIFO WITHOUT updating read pointer +static inline void _ff_pull(tu_fifo_t* f, void * app_buf, uint16_t rel) +{ + memcpy(app_buf, f->buffer + (rel * f->item_size), f->item_size); +} + +// get n items from FIFO WITHOUT updating read pointer +static void _ff_pull_n(tu_fifo_t* f, void* app_buf, uint16_t n, uint16_t rel, tu_fifo_copy_mode_t copy_mode) +{ + uint16_t const nLin = f->depth - rel; + uint16_t const nWrap = n - nLin; // only used if wrapped + + uint16_t nLin_bytes = nLin * f->item_size; + uint16_t nWrap_bytes = nWrap * f->item_size; + + // current buffer of fifo + uint8_t* ff_buf = f->buffer + (rel * f->item_size); + + switch (copy_mode) + { + case TU_FIFO_COPY_INC: + if ( n <= nLin ) + { + // Linear only + memcpy(app_buf, ff_buf, n*f->item_size); + } + else + { + // Wrap around + + // Read data from linear part of buffer + memcpy(app_buf, ff_buf, nLin_bytes); + + // Read data wrapped part + memcpy((uint8_t*) app_buf + nLin_bytes, f->buffer, nWrap_bytes); + } + break; + + case TU_FIFO_COPY_CST_FULL_WORDS: + if ( n <= nLin ) + { + // Linear only + _ff_pull_const_addr(app_buf, ff_buf, n*f->item_size); + } + else + { + // Wrap around case + + // Read full words from linear part of buffer + uint16_t nLin_4n_bytes = nLin_bytes & 0xFFFC; + _ff_pull_const_addr(app_buf, ff_buf, nLin_4n_bytes); + ff_buf += nLin_4n_bytes; + + // There could be odd 1-3 bytes before the wrap-around boundary + volatile uint32_t * tx_fifo = (volatile uint32_t *) app_buf; + uint8_t rem = nLin_bytes & 0x03; + if (rem > 0) + { + uint8_t remrem = tu_min16(nWrap_bytes, 4-rem); + nWrap_bytes -= remrem; + + uint32_t tmp32=0; + uint8_t * dst_u8 = (uint8_t *)&tmp32; + + // Read 1-3 bytes before wrapped boundary + while(rem--) *dst_u8++ = *ff_buf++; + + // Read more bytes from beginning to complete a word + ff_buf = f->buffer; + while(remrem--) *dst_u8++ = *ff_buf++; + + *tx_fifo = tmp32; + } + else + { + ff_buf = f->buffer; // wrap around to beginning + } + + // Read data wrapped part + if (nWrap_bytes > 0) _ff_pull_const_addr(app_buf, ff_buf, nWrap_bytes); + } + break; + + default: break; + } +} + +// Advance an absolute pointer +static uint16_t advance_pointer(tu_fifo_t* f, uint16_t p, uint16_t offset) +{ + // We limit the index space of p such that a correct wrap around happens + // Check for a wrap around or if we are in unused index space - This has to be checked first!! + // We are exploiting the wrap around to the correct index + if ((p > (uint16_t)(p + offset)) || ((uint16_t)(p + offset) > f->max_pointer_idx)) + { + p = (p + offset) + f->non_used_index_space; + } + else + { + p += offset; + } + return p; +} + +// Backward an absolute pointer +static uint16_t backward_pointer(tu_fifo_t* f, uint16_t p, uint16_t offset) +{ + // We limit the index space of p such that a correct wrap around happens + // Check for a wrap around or if we are in unused index space - This has to be checked first!! + // We are exploiting the wrap around to the correct index + if ((p < (uint16_t)(p - offset)) || ((uint16_t)(p - offset) > f->max_pointer_idx)) + { + p = (p - offset) - f->non_used_index_space; + } + else + { + p -= offset; + } + return p; +} + +// get relative from absolute pointer +static uint16_t get_relative_pointer(tu_fifo_t* f, uint16_t p) +{ + return _ff_mod(p, f->depth); +} + +// Works on local copies of w and r - return only the difference and as such can be used to determine an overflow +static inline uint16_t _tu_fifo_count(tu_fifo_t* f, uint16_t wAbs, uint16_t rAbs) +{ + uint16_t cnt = wAbs-rAbs; + + // In case we have non-power of two depth we need a further modification + if (rAbs > wAbs) cnt -= f->non_used_index_space; + + return cnt; +} + +// Works on local copies of w and r +static inline bool _tu_fifo_empty(uint16_t wAbs, uint16_t rAbs) +{ + return wAbs == rAbs; +} + +// Works on local copies of w and r +static inline bool _tu_fifo_full(tu_fifo_t* f, uint16_t wAbs, uint16_t rAbs) +{ + return (_tu_fifo_count(f, wAbs, rAbs) == f->depth); +} + +// Works on local copies of w and r +// BE AWARE - THIS FUNCTION MIGHT NOT GIVE A CORRECT ANSWERE IN CASE WRITE POINTER "OVERFLOWS" +// Only one overflow is allowed for this function to work e.g. if depth = 100, you must not +// write more than 2*depth-1 items in one rush without updating write pointer. Otherwise +// write pointer wraps and you pointer states are messed up. This can only happen if you +// use DMAs, write functions do not allow such an error. +static inline bool _tu_fifo_overflowed(tu_fifo_t* f, uint16_t wAbs, uint16_t rAbs) +{ + return (_tu_fifo_count(f, wAbs, rAbs) > f->depth); +} + +// Works on local copies of w +// For more details see _tu_fifo_overflow()! +static inline void _tu_fifo_correct_read_pointer(tu_fifo_t* f, uint16_t wAbs) +{ + f->rd_idx = backward_pointer(f, wAbs, f->depth); +} + +// Works on local copies of w and r +// Must be protected by mutexes since in case of an overflow read pointer gets modified +static bool _tu_fifo_peek(tu_fifo_t* f, void * p_buffer, uint16_t wAbs, uint16_t rAbs) +{ + uint16_t cnt = _tu_fifo_count(f, wAbs, rAbs); + + // Check overflow and correct if required + if (cnt > f->depth) + { + _tu_fifo_correct_read_pointer(f, wAbs); + cnt = f->depth; + } + + // Skip beginning of buffer + if (cnt == 0) return false; + + uint16_t rRel = get_relative_pointer(f, rAbs); + + // Peek data + _ff_pull(f, p_buffer, rRel); + + return true; +} + +// Works on local copies of w and r +// Must be protected by mutexes since in case of an overflow read pointer gets modified +static uint16_t _tu_fifo_peek_n(tu_fifo_t* f, void * p_buffer, uint16_t n, uint16_t wAbs, uint16_t rAbs, tu_fifo_copy_mode_t copy_mode) +{ + uint16_t cnt = _tu_fifo_count(f, wAbs, rAbs); + + // Check overflow and correct if required + if (cnt > f->depth) + { + _tu_fifo_correct_read_pointer(f, wAbs); + rAbs = f->rd_idx; + cnt = f->depth; + } + + // Skip beginning of buffer + if (cnt == 0) return 0; + + // Check if we can read something at and after offset - if too less is available we read what remains + if (cnt < n) n = cnt; + + uint16_t rRel = get_relative_pointer(f, rAbs); + + // Peek data + _ff_pull_n(f, p_buffer, n, rRel, copy_mode); + + return n; +} + +// Works on local copies of w and r +static inline uint16_t _tu_fifo_remaining(tu_fifo_t* f, uint16_t wAbs, uint16_t rAbs) +{ + return f->depth - _tu_fifo_count(f, wAbs, rAbs); +} + +static uint16_t _tu_fifo_write_n(tu_fifo_t* f, const void * data, uint16_t n, tu_fifo_copy_mode_t copy_mode) +{ + if ( n == 0 ) return 0; + + _ff_lock(f->mutex_wr); + + uint16_t w = f->wr_idx, r = f->rd_idx; + uint8_t const* buf8 = (uint8_t const*) data; + + if (!f->overwritable) + { + // Not overwritable limit up to full + n = tu_min16(n, _tu_fifo_remaining(f, w, r)); + } + else if (n >= f->depth) + { + // Only copy last part + buf8 = buf8 + (n - f->depth) * f->item_size; + n = f->depth; + + // We start writing at the read pointer's position since we fill the complete + // buffer and we do not want to modify the read pointer within a write function! + // This would end up in a race condition with read functions! + w = r; + } + + uint16_t wRel = get_relative_pointer(f, w); + + // Write data + _ff_push_n(f, buf8, n, wRel, copy_mode); + + // Advance pointer + f->wr_idx = advance_pointer(f, w, n); + + _ff_unlock(f->mutex_wr); + + return n; +} + +static uint16_t _tu_fifo_read_n(tu_fifo_t* f, void * buffer, uint16_t n, tu_fifo_copy_mode_t copy_mode) +{ + _ff_lock(f->mutex_rd); + + // Peek the data + // f->rd_idx might get modified in case of an overflow so we can not use a local variable + n = _tu_fifo_peek_n(f, buffer, n, f->wr_idx, f->rd_idx, copy_mode); + + // Advance read pointer + f->rd_idx = advance_pointer(f, f->rd_idx, n); + + _ff_unlock(f->mutex_rd); + return n; +} + +/******************************************************************************/ +/*! + @brief Get number of items in FIFO. + + As this function only reads the read and write pointers once, this function is + reentrant and thus thread and ISR save without any mutexes. In case an + overflow occurred, this function return f.depth at maximum. Overflows are + checked and corrected for in the read functions! + + @param[in] f + Pointer to the FIFO buffer to manipulate + + @returns Number of items in FIFO + */ +/******************************************************************************/ +uint16_t tu_fifo_count(tu_fifo_t* f) +{ + return tu_min16(_tu_fifo_count(f, f->wr_idx, f->rd_idx), f->depth); +} + +/******************************************************************************/ +/*! + @brief Check if FIFO is empty. + + As this function only reads the read and write pointers once, this function is + reentrant and thus thread and ISR save without any mutexes. + + @param[in] f + Pointer to the FIFO buffer to manipulate + + @returns Number of items in FIFO + */ +/******************************************************************************/ +bool tu_fifo_empty(tu_fifo_t* f) +{ + return _tu_fifo_empty(f->wr_idx, f->rd_idx); +} + +/******************************************************************************/ +/*! + @brief Check if FIFO is full. + + As this function only reads the read and write pointers once, this function is + reentrant and thus thread and ISR save without any mutexes. + + @param[in] f + Pointer to the FIFO buffer to manipulate + + @returns Number of items in FIFO + */ +/******************************************************************************/ +bool tu_fifo_full(tu_fifo_t* f) +{ + return _tu_fifo_full(f, f->wr_idx, f->rd_idx); +} + +/******************************************************************************/ +/*! + @brief Get remaining space in FIFO. + + As this function only reads the read and write pointers once, this function is + reentrant and thus thread and ISR save without any mutexes. + + @param[in] f + Pointer to the FIFO buffer to manipulate + + @returns Number of items in FIFO + */ +/******************************************************************************/ +uint16_t tu_fifo_remaining(tu_fifo_t* f) +{ + return _tu_fifo_remaining(f, f->wr_idx, f->rd_idx); +} + +/******************************************************************************/ +/*! + @brief Check if overflow happened. + + BE AWARE - THIS FUNCTION MIGHT NOT GIVE A CORRECT ANSWERE IN CASE WRITE POINTER "OVERFLOWS" + Only one overflow is allowed for this function to work e.g. if depth = 100, you must not + write more than 2*depth-1 items in one rush without updating write pointer. Otherwise + write pointer wraps and your pointer states are messed up. This can only happen if you + use DMAs, write functions do not allow such an error. Avoid such nasty things! + + All reading functions (read, peek) check for overflows and correct read pointer on their own such + that latest items are read. + If required (e.g. for DMA use) you can also correct the read pointer by + tu_fifo_correct_read_pointer(). + + @param[in] f + Pointer to the FIFO buffer to manipulate + + @returns True if overflow happened + */ +/******************************************************************************/ +bool tu_fifo_overflowed(tu_fifo_t* f) +{ + return _tu_fifo_overflowed(f, f->wr_idx, f->rd_idx); +} + +// Only use in case tu_fifo_overflow() returned true! +void tu_fifo_correct_read_pointer(tu_fifo_t* f) +{ + _ff_lock(f->mutex_rd); + _tu_fifo_correct_read_pointer(f, f->wr_idx); + _ff_unlock(f->mutex_rd); +} + +/******************************************************************************/ +/*! + @brief Read one element out of the buffer. + + This function will return the element located at the array index of the + read pointer, and then increment the read pointer index. + This function checks for an overflow and corrects read pointer if required. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] buffer + Pointer to the place holder for data read from the buffer + + @returns TRUE if the queue is not empty + */ +/******************************************************************************/ +bool tu_fifo_read(tu_fifo_t* f, void * buffer) +{ + _ff_lock(f->mutex_rd); + + // Peek the data + // f->rd_idx might get modified in case of an overflow so we can not use a local variable + bool ret = _tu_fifo_peek(f, buffer, f->wr_idx, f->rd_idx); + + // Advance pointer + f->rd_idx = advance_pointer(f, f->rd_idx, ret); + + _ff_unlock(f->mutex_rd); + return ret; +} + +/******************************************************************************/ +/*! + @brief This function will read n elements from the array index specified by + the read pointer and increment the read index. + This function checks for an overflow and corrects read pointer if required. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] buffer + The pointer to data location + @param[in] n + Number of element that buffer can afford + + @returns number of items read from the FIFO + */ +/******************************************************************************/ +uint16_t tu_fifo_read_n(tu_fifo_t* f, void * buffer, uint16_t n) +{ + return _tu_fifo_read_n(f, buffer, n, TU_FIFO_COPY_INC); +} + +uint16_t tu_fifo_read_n_const_addr_full_words(tu_fifo_t* f, void * buffer, uint16_t n) +{ + return _tu_fifo_read_n(f, buffer, n, TU_FIFO_COPY_CST_FULL_WORDS); +} + +/******************************************************************************/ +/*! + @brief Read one item without removing it from the FIFO. + This function checks for an overflow and corrects read pointer if required. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] offset + Position to read from in the FIFO buffer with respect to read pointer + @param[in] p_buffer + Pointer to the place holder for data read from the buffer + + @returns TRUE if the queue is not empty + */ +/******************************************************************************/ +bool tu_fifo_peek(tu_fifo_t* f, void * p_buffer) +{ + _ff_lock(f->mutex_rd); + bool ret = _tu_fifo_peek(f, p_buffer, f->wr_idx, f->rd_idx); + _ff_unlock(f->mutex_rd); + return ret; +} + +/******************************************************************************/ +/*! + @brief Read n items without removing it from the FIFO + This function checks for an overflow and corrects read pointer if required. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] p_buffer + Pointer to the place holder for data read from the buffer + @param[in] n + Number of items to peek + + @returns Number of bytes written to p_buffer + */ +/******************************************************************************/ +uint16_t tu_fifo_peek_n(tu_fifo_t* f, void * p_buffer, uint16_t n) +{ + _ff_lock(f->mutex_rd); + bool ret = _tu_fifo_peek_n(f, p_buffer, n, f->wr_idx, f->rd_idx, TU_FIFO_COPY_INC); + _ff_unlock(f->mutex_rd); + return ret; +} + +/******************************************************************************/ +/*! + @brief Write one element into the buffer. + + This function will write one element into the array index specified by + the write pointer and increment the write index. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] data + The byte to add to the FIFO + + @returns TRUE if the data was written to the FIFO (overwrittable + FIFO will always return TRUE) + */ +/******************************************************************************/ +bool tu_fifo_write(tu_fifo_t* f, const void * data) +{ + _ff_lock(f->mutex_wr); + + uint16_t w = f->wr_idx; + + if ( _tu_fifo_full(f, w, f->rd_idx) && !f->overwritable ) return false; + + uint16_t wRel = get_relative_pointer(f, w); + + // Write data + _ff_push(f, data, wRel); + + // Advance pointer + f->wr_idx = advance_pointer(f, w, 1); + + _ff_unlock(f->mutex_wr); + + return true; +} + +/******************************************************************************/ +/*! + @brief This function will write n elements into the array index specified by + the write pointer and increment the write index. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] data + The pointer to data to add to the FIFO + @param[in] count + Number of element + @return Number of written elements + */ +/******************************************************************************/ +uint16_t tu_fifo_write_n(tu_fifo_t* f, const void * data, uint16_t n) +{ + return _tu_fifo_write_n(f, data, n, TU_FIFO_COPY_INC); +} + +/******************************************************************************/ +/*! + @brief This function will write n elements into the array index specified by + the write pointer and increment the write index. The source address will + not be incremented which is useful for reading from registers. + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] data + The pointer to data to add to the FIFO + @param[in] count + Number of element + @return Number of written elements + */ +/******************************************************************************/ +uint16_t tu_fifo_write_n_const_addr_full_words(tu_fifo_t* f, const void * data, uint16_t n) +{ + return _tu_fifo_write_n(f, data, n, TU_FIFO_COPY_CST_FULL_WORDS); +} + +/******************************************************************************/ +/*! + @brief Clear the fifo read and write pointers + + @param[in] f + Pointer to the FIFO buffer to manipulate + */ +/******************************************************************************/ +bool tu_fifo_clear(tu_fifo_t *f) +{ + _ff_lock(f->mutex_wr); + _ff_lock(f->mutex_rd); + + f->rd_idx = f->wr_idx = 0; + f->max_pointer_idx = 2*f->depth-1; + f->non_used_index_space = UINT16_MAX - f->max_pointer_idx; + + _ff_unlock(f->mutex_wr); + _ff_unlock(f->mutex_rd); + return true; +} + +/******************************************************************************/ +/*! + @brief Change the fifo mode to overwritable or not overwritable + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] overwritable + Overwritable mode the fifo is set to + */ +/******************************************************************************/ +bool tu_fifo_set_overwritable(tu_fifo_t *f, bool overwritable) +{ + _ff_lock(f->mutex_wr); + _ff_lock(f->mutex_rd); + + f->overwritable = overwritable; + + _ff_unlock(f->mutex_wr); + _ff_unlock(f->mutex_rd); + + return true; +} + +/******************************************************************************/ +/*! + @brief Advance write pointer - intended to be used in combination with DMA. + It is possible to fill the FIFO by use of a DMA in circular mode. Within + DMA ISRs you may update the write pointer to be able to read from the FIFO. + As long as the DMA is the only process writing into the FIFO this is safe + to use. + + USE WITH CARE - WE DO NOT CONDUCT SAFTY CHECKS HERE! + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] n + Number of items the write pointer moves forward + */ +/******************************************************************************/ +void tu_fifo_advance_write_pointer(tu_fifo_t *f, uint16_t n) +{ + f->wr_idx = advance_pointer(f, f->wr_idx, n); +} + +/******************************************************************************/ +/*! + @brief Advance read pointer - intended to be used in combination with DMA. + It is possible to read from the FIFO by use of a DMA in linear mode. Within + DMA ISRs you may update the read pointer to be able to again write into the + FIFO. As long as the DMA is the only process reading from the FIFO this is + safe to use. + + USE WITH CARE - WE DO NOT CONDUCT SAFTY CHECKS HERE! + + @param[in] f + Pointer to the FIFO buffer to manipulate + @param[in] n + Number of items the read pointer moves forward + */ +/******************************************************************************/ +void tu_fifo_advance_read_pointer(tu_fifo_t *f, uint16_t n) +{ + f->rd_idx = advance_pointer(f, f->rd_idx, n); +} + +/******************************************************************************/ +/*! + @brief Get read info + + Returns the length and pointer from which bytes can be read in a linear manner. + This is of major interest for DMA transmissions. If returned length is zero the + corresponding pointer is invalid. + The read pointer does NOT get advanced, use tu_fifo_advance_read_pointer() to + do so! + @param[in] f + Pointer to FIFO + @param[out] *info + Pointer to struct which holds the desired infos + */ +/******************************************************************************/ +void tu_fifo_get_read_info(tu_fifo_t *f, tu_fifo_buffer_info_t *info) +{ + // Operate on temporary values in case they change in between + uint16_t w = f->wr_idx, r = f->rd_idx; + + uint16_t cnt = _tu_fifo_count(f, w, r); + + // Check overflow and correct if required - may happen in case a DMA wrote too fast + if (cnt > f->depth) + { + _ff_lock(f->mutex_rd); + _tu_fifo_correct_read_pointer(f, w); + _ff_unlock(f->mutex_rd); + r = f->rd_idx; + cnt = f->depth; + } + + // Check if fifo is empty + if (cnt == 0) + { + info->len_lin = 0; + info->len_wrap = 0; + info->ptr_lin = NULL; + info->ptr_wrap = NULL; + return; + } + + // Get relative pointers + w = get_relative_pointer(f, w); + r = get_relative_pointer(f, r); + + // Copy pointer to buffer to start reading from + info->ptr_lin = &f->buffer[r]; + + // Check if there is a wrap around necessary + if (w > r) { + // Non wrapping case + info->len_lin = cnt; + info->len_wrap = 0; + info->ptr_wrap = NULL; + } + else + { + info->len_lin = f->depth - r; // Also the case if FIFO was full + info->len_wrap = cnt - info->len_lin; + info->ptr_wrap = f->buffer; + } +} + +/******************************************************************************/ +/*! + @brief Get linear write info + + Returns the length and pointer to which bytes can be written into FIFO in a linear manner. + This is of major interest for DMA transmissions not using circular mode. If a returned length is zero the + corresponding pointer is invalid. The returned lengths summed up are the currently free space in the FIFO. + The write pointer does NOT get advanced, use tu_fifo_advance_write_pointer() to do so! + TAKE CARE TO NOT OVERFLOW THE BUFFER MORE THAN TWO TIMES THE FIFO DEPTH - IT CAN NOT RECOVERE OTHERWISE! + @param[in] f + Pointer to FIFO + @param[out] *info + Pointer to struct which holds the desired infos + */ +/******************************************************************************/ +void tu_fifo_get_write_info(tu_fifo_t *f, tu_fifo_buffer_info_t *info) +{ + uint16_t w = f->wr_idx, r = f->rd_idx; + uint16_t free = _tu_fifo_remaining(f, w, r); + + if (free == 0) + { + info->len_lin = 0; + info->len_wrap = 0; + info->ptr_lin = NULL; + info->ptr_wrap = NULL; + return; + } + + // Get relative pointers + w = get_relative_pointer(f, w); + r = get_relative_pointer(f, r); + + // Copy pointer to buffer to start writing to + info->ptr_lin = &f->buffer[w]; + + if (w < r) + { + // Non wrapping case + info->len_lin = r-w; + info->len_wrap = 0; + info->ptr_wrap = NULL; + } + else + { + info->len_lin = f->depth - w; + info->len_wrap = free - info->len_lin; // Remaining length - n already was limited to free or FIFO depth + info->ptr_wrap = f->buffer; // Always start of buffer + } +} |