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git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@1188 35acf78f-673a-0410-8e92-d51de3d6d3f4

master
gdisirio 2009-09-27 13:53:06 +00:00
parent 7f4861c9ea
commit 85eea6f195
1 changed files with 66 additions and 0 deletions
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66
os/io/platforms/AT91SAM7X/mac_lld.c
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@ -282,7 +282,65 @@ uint8_t *mac_lld_get_transmit_buffer(MACTransmitDescriptor *tdp) {
*/
MACReceiveDescriptor *max_lld_get_receive_descriptor(MACDriver *macp,
size_t *szp) {
unsigned n;
MACReceiveDescriptor *rdp;
n = EMAC_RECEIVE_BUFFERS;
/*
* Skips unused buffers, if any.
*/
skip:
while ((n > 0) && !(rxptr->w1 & W1_R_OWNERSHIP)) {
if (++rxptr >= &rd[EMAC_RECEIVE_BUFFERS])
rxptr = rd;
n--;
}
/*
* Skips fragments, if any, cleaning them up.
*/
while ((n > 0) && (rxptr->w1 & W1_R_OWNERSHIP) &&
!(rxptr->w2 & W2_R_FRAME_START)) {
rxptr->w1 &= ~W1_R_OWNERSHIP;
if (++rxptr >= &rd[EMAC_RECEIVE_BUFFERS])
rxptr = rd;
n--;
}
/*
* Now compute the total frame size skipping eventual incomplete frames
* or holes...
*/
restart:
rdp = rxptr;
while (n > 0) {
if (!(rxptr->w1 & W1_R_OWNERSHIP))
goto skip; /* Empty buffer for some reason... */
/*
* End Of Frame found.
*/
if (rxptr->w2 & W2_R_FRAME_END) {
*szp = rxptr->w2 & W2_T_LENGTH_MASK;
return rdp;
}
if ((rdp != rxptr) && (rxptr->w2 & W2_R_FRAME_START)) {
/* Found another start... cleaning up the incomplete frame.*/
do {
rdp->w1 &= ~W1_R_OWNERSHIP;
if (++rdp >= &rd[EMAC_RECEIVE_BUFFERS])
rdp = rd;
}
while (rdp != rxptr);
goto restart; /* Another start buffer for some reason... */
}
if (++rxptr >= &rd[EMAC_RECEIVE_BUFFERS])
rxptr = rd;
n--;
}
return NULL;
}
@ -297,6 +355,14 @@ MACReceiveDescriptor *max_lld_get_receive_descriptor(MACDriver *macp,
void mac_lld_release_receive_descriptor(MACDriver *macp,
MACReceiveDescriptor *rdp) {
unsigned n = EMAC_RECEIVE_BUFFERS;
do {
rdp->w1 &= ~W1_R_OWNERSHIP;
if (++rdp >= &rd[EMAC_RECEIVE_BUFFERS])
rdp = rd;
n--;
}
while ((n > 0) || !(rxptr->w2 & W2_R_FRAME_END));
}
/**