/*!
* \brief Load a packet into the nic's transmit ring buffer.
*
* Interupts must have been disabled when calling this function.
*
* \param nb Network buffer structure containing the packet to be sent.
* The structure must have been allocated by a previous
* call NutNetBufAlloc(). This routine will automatically
* release the buffer in case of an error.
*
* \return 0 on success, -1 in case of any errors. Errors
* will automatically release the network buffer
* structure.
*/
static int NicPutPacket(NETBUF * nb)
{
u_int16_t sz;
uint8_t odd = 0;
uint8_t imsk;
//printf("[P]");
/*
* Calculate the number of bytes to be send. Do not send packets
* larger than the Ethernet maximum transfer unit. The MTU
* consist of 1500 data bytes plus the 14 byte Ethernet header
* plus 4 bytes CRC. We check the data bytes only.
*/
if ((sz = nb->nb_nw.sz + nb->nb_tp.sz + nb->nb_ap.sz) > ETH_DATA_LEN)
return -1;
/* Disable all interrupts. */
imsk = nic_inlb(NIC_MSK);
nic_outlb(NIC_MSK, 0);
/* Allocate packet buffer space. */
nic_bs(2);
nic_outlb(NIC_MMUCR, MMU_ALO);
if (NicMmuWait(100))
return -1;
/* Enable interrupts including allocation success. */
nic_outlb(NIC_MSK, imsk | INT_ALLOC);
/* The MMU needs some time. Use it to calculate the byte count. */
sz += nb->nb_dl.sz;
sz += 6;
if (sz & 1) {
sz++;
odd++;
}
/* Wait for allocation success. */
while ((nic_inlb(NIC_IST) & INT_ALLOC) == 0) {
if (NutEventWait(&maq, 125)) {
nic_outlb(NIC_MMUCR, MMU_RST);
NicMmuWait(1000);
nic_outlb(NIC_MMUCR, MMU_ALO);
if (NicMmuWait(100) || (nic_inlb(NIC_IST) & INT_ALLOC) == 0) {
if (NutEventWait(&maq, 125)) {
return -1;
}
}
}
}
/* Disable interrupts. */
imsk = nic_inlb(NIC_MSK);
nic_outlb(NIC_MSK, 0);
nic_outlb(NIC_PNR, nic_inhb(NIC_PNR));
nic_outw(NIC_PTR, 0x4000);
/* Transfer control word. */
nic_outlb(NIC_DATA, 0);
nic_outlb(NIC_DATA, 0);
/* Transfer the byte count. */
nic_outw(NIC_DATA, sz);
/* Transfer the Ethernet frame. */
NicWrite(nb->nb_dl.vp, nb->nb_dl.sz);
NicWrite(nb->nb_nw.vp, nb->nb_nw.sz);
NicWrite(nb->nb_tp.vp, nb->nb_tp.sz);
NicWrite(nb->nb_ap.vp, nb->nb_ap.sz);
if (odd)
nic_outlb(NIC_DATA, 0);
/* Transfer the control word. */
nic_outw(NIC_DATA, 0);
/* Enqueue packet. */
if (NicMmuWait(100))
return -1;
nic_outlb(NIC_MMUCR, MMU_ENQ);
/* Enable interrupts. */
imsk |= INT_TX | INT_TX_EMPTY;
nic_outlb(NIC_MSK, imsk);
return 0;
}
/*!
* \brief Send an Ethernet frame.
*
* \param dmac Destination MAC address.
* \param type Frame type.
* \param len Frame size.
*
* \return 0 on success, -1 otherwise.
*/
int EtherOutput(const u_char * dmac, u_short type, u_short len)
{
ETHERHDR *eh;
u_char *cp;
/*
* Set the Ethernet header.
*/
if (type == ETHERTYPE_ARP) {
cp = (u_char *) & arpframe;
} else {
cp = (u_char *) & sframe;
}
eh = (ETHERHDR *)cp;
memcpy_(eh->ether_shost, confnet.cdn_mac, 6);
memcpy_(eh->ether_dhost, dmac, 6);
eh->ether_type = type;
/*
* The total packet length includes
* - status word (2 bytes)
* - byte count (2 bytes)
* - destination address (6 bytes)
* - source address (6 bytes)
* - Ethernet type (2 bytes)
* - data bytes (variable)
* - control word (2 bytes)
* Thus we add 20 to the number of data bytes. We didn't
* manage to get an odd number of bytes transmitted, so
* add another byte.
*/
if((len += 20) & 1) {
len++;
}
DEBUG(" Tx(");
DEBUGUSHORT(len);
DEBUG(")");
/* Allocate transmit packet buffer space. */
nic_bs(2);
nic_outlb(NIC_MMUCR, MMU_ALO);
if (NicMmuWait(100)) {
return -1;
}
/*
* An allocation error might appear when incoming packets occupy
* all the buffer. Reset the MMU to release all memory. This is
* very drastic, but OK for our sequential boot loader.
*/
if ((nic_inlb(NIC_IST) & INT_ALLOC) == 0) {
DEBUG("[MMURST]");
nic_outlb(NIC_MMUCR, MMU_RST);
NicMmuWait(1000);
nic_outlb(NIC_MMUCR, MMU_ALO);
if (NicMmuWait(100) || (nic_inlb(NIC_IST) & INT_ALLOC) == 0) {
return -1;
}
}
/*
* Read the number of the allcocated packet from the allocation
* result register and write it to the packet number register.
*/
nic_outlb(NIC_PNR, nic_inhb(NIC_PNR));
/*
* Initially set the pointer register address to 2 and enable
* auto increment. The first two bytes will be used by the CSMA
* to store the status word upon transmit completion.
*/
nic_outw(NIC_PTR, PTR_AUTO_INCR | 2);
/*
* Transfer the byte count and the data bytes.
*/
nic_outw(NIC_DATA, len);
while (len--) {
nic_outlb(NIC_DATA, *cp);
cp++;
}
/*
* Transfer the control word. As stated above, we never succeeded
* in sending an odd number of bytes.
*/
nic_outw(NIC_DATA, 0);
/* Enqueue packet. */
NicMmuWait(100);
nic_outlb(NIC_MMUCR, MMU_ENQ);
return 0;
}
