Add FIFO copy modes: tu_fifo_copy_mode_t

Allows to copy from/to constant pointers required for STM32 hardware
FIFO copies.
This commit is contained in:
Reinhard Panhuber 2021-01-18 17:12:39 +01:00
parent 84c383061f
commit 8450bc3225
2 changed files with 127 additions and 6 deletions

View File

@ -76,6 +76,8 @@ bool tu_fifo_config(tu_fifo_t *f, void* buffer, uint16_t depth, uint16_t item_si
f->max_pointer_idx = 2*depth - 1; // 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->non_used_index_space = 0xFFFF - f->max_pointer_idx;
f->rd_mode = f->wr_mode = TU_FIFO_COPY_INC; // Default copy mode is incrementing addresses
f->rd_idx = f->wr_idx = 0;
tu_fifo_unlock(f);
@ -91,28 +93,117 @@ static inline uint16_t _ff_mod(uint16_t idx, uint16_t 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
static void _tu_fifo_read_from_const_src_ptr(void * dst, const void * src, uint16_t len)
{
uint8_t * dst_u8 = (uint8_t *)dst;
volatile uint32_t * rx_fifo = (volatile uint32_t *) src;
// Reading full available 32 bit words from FIFO
uint16_t full_words = len >> 2;
for(uint16_t i = 0; i < full_words; i++) {
uint32_t tmp = *rx_fifo;
dst_u8[0] = tmp & 0x000000FF;
dst_u8[1] = (tmp & 0x0000FF00) >> 8;
dst_u8[2] = (tmp & 0x00FF0000) >> 16;
dst_u8[3] = (tmp & 0xFF000000) >> 24;
dst_u8 += 4;
}
// Read the remaining 1-3 bytes from FIFO
uint8_t bytes_rem = len & 0x03;
if(bytes_rem != 0) {
uint32_t tmp = *rx_fifo;
dst_u8[0] = tmp & 0x000000FF;
if(bytes_rem > 1) {
dst_u8[1] = (tmp & 0x0000FF00) >> 8;
}
if(bytes_rem > 2) {
dst_u8[2] = (tmp & 0x00FF0000) >> 16;
}
}
}
// Intended to be used to write to hardware USB FIFO in e.g. STM32 where all data is written to a constant address
// Code adapted from dcd_synopsis.c
static void _tu_fifo_write_to_const_dst_ptr(void * dst, const void * src, uint16_t len)
{
volatile uint32_t * tx_fifo = (volatile uint32_t *) dst;
uint8_t * src_u8 = (uint8_t *)src;
// Pushing full available 32 bit words to FIFO
uint16_t full_words = len >> 2;
for(uint16_t i = 0; i < full_words; i++){
*tx_fifo = (src_u8[3] << 24) | (src_u8[2] << 16) | (src_u8[1] << 8) | src_u8[0];
src_u8 += 4;
}
// Write the remaining 1-3 bytes into FIFO
uint8_t bytes_rem = len & 0x03;
if(bytes_rem){
uint32_t tmp_word = 0;
tmp_word |= src_u8[0];
if(bytes_rem > 1){
tmp_word |= src_u8[1] << 8;
}
if(bytes_rem > 2){
tmp_word |= src_u8[2] << 16;
}
*tx_fifo = tmp_word;
}
}
// send one item to FIFO WITHOUT updating write pointer
static inline void _ff_push(tu_fifo_t* f, void const * data, uint16_t wRel)
{
memcpy(f->buffer + (wRel * f->item_size), data, f->item_size);
}
static inline void _ff_push_copy_fct(tu_fifo_t* f, void * dst, const void * src, uint16_t len)
{
switch (f->rd_mode)
{
case TU_FIFO_COPY_INC:
memcpy(dst, src, len);
break;
case TU_FIFO_COPY_CST:
_tu_fifo_read_from_const_src_ptr(dst, src, len);
break;
}
}
static inline void _ff_pull_copy_fct(tu_fifo_t* f, void * dst, const void * src, uint16_t len)
{
switch (f->wr_mode)
{
case TU_FIFO_COPY_INC:
memcpy(dst, src, len);
break;
case TU_FIFO_COPY_CST:
_tu_fifo_write_to_const_dst_ptr(dst, src, len);
break;
}
}
// send n items to FIFO WITHOUT updating write pointer
static void _ff_push_n(tu_fifo_t* f, void const * data, uint16_t n, uint16_t wRel)
{
if(wRel + n <= f->depth) // Linear mode only
{
memcpy(f->buffer + (wRel * f->item_size), data, n*f->item_size);
_ff_push_copy_fct(f, f->buffer + (wRel * f->item_size), data, n*f->item_size);
}
else // Wrap around
{
uint16_t nLin = f->depth - wRel;
// Write data to linear part of buffer
memcpy(f->buffer + (wRel * f->item_size), data, nLin*f->item_size);
_ff_push_copy_fct(f, f->buffer + (wRel * f->item_size), data, nLin*f->item_size);
// Write data wrapped around
memcpy(f->buffer, ((uint8_t const*) data) + nLin*f->item_size, (n - nLin) * f->item_size);
_ff_push_copy_fct(f, f->buffer, ((uint8_t const*) data) + nLin*f->item_size, (n - nLin) * f->item_size);
}
}
@ -127,17 +218,17 @@ static void _ff_pull_n(tu_fifo_t* f, void * p_buffer, uint16_t n, uint16_t rRel)
{
if(rRel + n <= f->depth) // Linear mode only
{
memcpy(p_buffer, f->buffer + (rRel * f->item_size), n*f->item_size);
_ff_pull_copy_fct(f, p_buffer, f->buffer + (rRel * f->item_size), n*f->item_size);
}
else // Wrap around
{
uint16_t nLin = f->depth - rRel;
// Read data from linear part of buffer
memcpy(p_buffer, f->buffer + (rRel * f->item_size), nLin*f->item_size);
_ff_pull_copy_fct(f, p_buffer, f->buffer + (rRel * f->item_size), nLin*f->item_size);
// Read data wrapped part
memcpy((uint8_t*)p_buffer + nLin*f->item_size, f->buffer, (n - nLin) * f->item_size);
_ff_pull_copy_fct(f, (uint8_t*)p_buffer + nLin*f->item_size, f->buffer, (n - nLin) * f->item_size);
}
}

View File

@ -55,6 +55,19 @@ extern "C" {
#define tu_fifo_mutex_t osal_mutex_t
#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
*/
typedef enum
{
TU_FIFO_COPY_INC, ///< Copy from/to an increasing source/destination address - default mode
TU_FIFO_COPY_CST, ///< Copy from/to a constant source/destination address - required for e.g. STM32 to write into USB hardware FIFO
} tu_fifo_copy_mode_t;
//TU_FIFO_WRITE_INC_DST, ///< Write to an increasing destination address - default mode
// TU_FIFO_WRITE_CONST_DST, ///< Write to a constant destination address - required for e.g. STM32 to write into USB hardware FIFO
// TU_FIFO_READ_INC_SRC, ///< Read from an increasing source address - default mode
// TU_FIFO_READ_CONST_SRC, ///< Read from a constant source address - required for e.g. STM32 to read from USB hardware FIFO
/** \struct tu_fifo_t
* \brief Simple Circular FIFO
@ -72,6 +85,9 @@ typedef struct
volatile uint16_t wr_idx ; ///< write pointer
volatile uint16_t rd_idx ; ///< read pointer
tu_fifo_copy_mode_t wr_mode ; ///< write mode - default is TU_FIFO_COPY_INC
tu_fifo_copy_mode_t rd_mode ; ///< read mode - default is TU_FIFO_COPY_INC
#if CFG_FIFO_MUTEX
tu_fifo_mutex_t mutex;
#endif
@ -87,6 +103,8 @@ typedef struct
.overwritable = _overwritable, \
.max_pointer_idx = 2*_depth-1, \
.non_used_index_space = 0xFFFF - 2*_depth-1, \
.wr_mode = TU_FIFO_COPY_INC, \
.rd_mode = TU_FIFO_COPY_INC, \
}
bool tu_fifo_set_overwritable(tu_fifo_t *f, bool overwritable);
@ -133,6 +151,18 @@ static inline uint16_t tu_fifo_depth(tu_fifo_t* f)
return f->depth;
}
// When writing into the FIFO by fifo_write_n(), rd_mode determines how the pointer read from is modified
static inline void tu_fifo_set_copy_mode_read(tu_fifo_t* f, tu_fifo_copy_mode_t rd_mode)
{
f->rd_mode = rd_mode;
}
// When reading from the FIFO by fifo_read_n() or fifo_peek_n(), wr_mode determines how the pointer written to is modified
static inline void tu_fifo_set_copy_mode_write(tu_fifo_t* f, tu_fifo_copy_mode_t wr_mode)
{
f->wr_mode = wr_mode;
}
#ifdef __cplusplus
}
#endif