esp-idf/components/soc/lldesc.c

47 wiersze
1.3 KiB
C

#include "soc/lldesc.h"
void lldesc_setup_link_constrained(lldesc_t *dmadesc, const void *data, int len, int max_desc_size, bool isrx)
{
int n = 0;
while (len) {
int dmachunklen = len;
if (dmachunklen > max_desc_size) {
dmachunklen = max_desc_size;
}
if (isrx) {
//Receive needs DMA length rounded to next 32-bit boundary
dmadesc[n].size = (dmachunklen + 3) & (~3);
dmadesc[n].length = (dmachunklen + 3) & (~3);
} else {
dmadesc[n].size = dmachunklen;
dmadesc[n].length = dmachunklen;
}
dmadesc[n].buf = (uint8_t *)data;
dmadesc[n].eof = 0;
dmadesc[n].sosf = 0;
dmadesc[n].owner = 1;
dmadesc[n].qe.stqe_next = &dmadesc[n + 1];
len -= dmachunklen;
data += dmachunklen;
n++;
}
dmadesc[n - 1].eof = 1; //Mark last DMA desc as end of stream.
dmadesc[n - 1].qe.stqe_next = NULL;
}
int lldesc_get_received_len(lldesc_t* head, lldesc_t** out_next)
{
lldesc_t* desc = head;
int len = 0;
while(desc) {
len += desc->length;
bool eof = desc->eof;
desc = STAILQ_NEXT(desc, qe);
if (eof) break;
}
if (out_next) {
*out_next = desc;
}
return len;
}