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more clean up for _ff_pull_const_addr_in_full_words()

This commit is contained in:
hathach 2021-04-06 23:39:39 +07:00
parent d82ee2f8c0
commit a3c06aa7bc
1 changed files with 33 additions and 31 deletions
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64
src/common/tusb_fifo.c
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@ -265,68 +265,68 @@ static inline void _ff_pull(tu_fifo_t* f, void * p_buffer, uint16_t rRel)
// get n items from FIFO WITHOUT updating read pointer
static void _ff_pull_n(tu_fifo_t* f, uint8_t* p_buffer, uint16_t n, uint16_t rRel, tu_fifo_copy_mode_t copy_mode)
{
uint16_t const nLin = f->depth - rRel;
uint16_t const nWrap = n - nLin; // only used if wrapped
switch (copy_mode)
{
case TU_FIFO_COPY_INC:
if ( n <= f->depth - rRel )
if ( n <= nLin )
{
// Linear mode only
// Linear only
memcpy(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);
// Read data wrapped part
memcpy(p_buffer + nLin*f->item_size, f->buffer, (n - nLin) * f->item_size);
memcpy(p_buffer + nLin*f->item_size, f->buffer, nWrap*f->item_size);
}
break;
break;
case TU_FIFO_COPY_CST_FULL_WORDS:
if ( n <= f->depth - rRel )
if ( n <= nLin )
{
// Linear mode only
_ff_pull_const_addr_in_full_words(p_buffer, f->buffer + (rRel * f->item_size), n*f->item_size);
}
else
{
// since it is const address, we don't increase p_buffer
volatile uint32_t * tx_fifo = (volatile uint32_t *) p_buffer;
// Wrap around case
uint16_t nLin_bytes = nLin * f->item_size;
uint16_t nWrap_bytes = nWrap * f->item_size;
uint8_t* src = f->buffer + (rRel * f->item_size);
// Wrap around case
uint16_t nLin = (f->depth - rRel) * f->item_size;
uint16_t nLin_4n = nLin & 0xFFFC;
uint16_t nWrap = (n - nLin) * f->item_size;
// Read data from linear part of buffer
_ff_pull_const_addr_in_full_words(p_buffer, src, nLin_4n);
src += nLin_4n;
uint16_t nLin_4n_bytes = nLin_bytes & 0xFFFC;
_ff_pull_const_addr_in_full_words(p_buffer, src, nLin_4n_bytes);
src += nLin_4n_bytes;
// There could be odd 1-3 bytes before the wrap-around boundary
// Handle wrap around - do it manually as these are only 4 bytes and its faster without memcpy
uint8_t rem = nLin & 0x03;
volatile uint32_t * tx_fifo = (volatile uint32_t *) p_buffer;
uint8_t rem = nLin_bytes & 0x03;
if (rem > 0)
{
uint8_t remrem = tu_min16(nWrap, 4-rem);
nWrap -= remrem;
uint8_t remrem = tu_min16(nWrap_bytes, 4-rem);
nWrap_bytes -= remrem;
uint32_t tmp;
uint8_t * dst_u8 = (uint8_t *)&tmp;
while(rem--)
{
*dst_u8++ = *src++;
}
// Get 1-3 bytes before wrapped boundary
while(rem--) *dst_u8++ = *src++;
// Get more bytes from beginning to form a complete word
src = f->buffer;
while(remrem--)
{
*dst_u8++ = *src++;
}
while(remrem--) *dst_u8++ = *src++;
*tx_fifo = tmp;
}
else
@ -334,10 +334,12 @@ static void _ff_pull_n(tu_fifo_t* f, uint8_t* p_buffer, uint16_t n, uint16_t rRe
src = f->buffer; // wrap around to beginning
}
// Final linear part
if (nWrap > 0) _ff_pull_const_addr_in_full_words(p_buffer, src, nWrap);
// Read data wrapped part
if (nWrap_bytes > 0) _ff_pull_const_addr_in_full_words(p_buffer, src, nWrap_bytes);
}
break;
break;
default: break;
}
}
// Advance an absolute pointer