Offload FCS to driver specific code

This commit is contained in:
retu2libc 2024-03-07 00:05:39 -05:00
parent 8662e5ca5e
commit 6c976d8b56
2 changed files with 10 additions and 5 deletions

View file

@ -635,7 +635,13 @@ I64 PCNetPacketReceive(U8 **packet_buffer_out, U16 *packet_length_out)
NetDebug("PCNET RECEIVE PACKET: de_index incremented = 0x%0X", pcnet.current_rx_de_index); NetDebug("PCNET RECEIVE PACKET: de_index incremented = 0x%0X", pcnet.current_rx_de_index);
*packet_buffer_out = pcnet.rx_buffer_addr_phys + de_index * ETHERNET_FRAME_SIZE; *packet_buffer_out = pcnet.rx_buffer_addr_phys + de_index * ETHERNET_FRAME_SIZE;
*packet_length_out = packet_length;
// ASTRPRCV causes 802.3 packets to be stripped and FCS to be checked
U16 ethertype = (*packet_buffer_out)[ETHERNET_ETHERTYPE_OFFSET + 1] | (*packet_buffer_out)[ETHERNET_ETHERTYPE_OFFSET] << 8;
if (ethertype < ETHERNET_v2_MTU)
*packet_length_out = ethertype;
else
*packet_length_out = packet_length - FCS_LENGTH; // ethertype ii TODO: Validate FCS
return de_index; return de_index;
} }

View file

@ -29,6 +29,8 @@ U0 EthernetGlobalsInit()
U0 EthernetFrameParse(CEthernetFrame *frame_out, U8 *frame, U16 length) U0 EthernetFrameParse(CEthernetFrame *frame_out, U8 *frame, U16 length)
{ {
// length is assumed to NOT include the FCS.
// Shrine says MemCopy has a high overhead. // Shrine says MemCopy has a high overhead.
// Almost tempted to say that means that a lot // Almost tempted to say that means that a lot
// of the current system should be done with // of the current system should be done with
@ -45,10 +47,7 @@ U0 EthernetFrameParse(CEthernetFrame *frame_out, U8 *frame, U16 length)
frame_out->data = frame + ETHERNET_DATA_OFFSET; frame_out->data = frame + ETHERNET_DATA_OFFSET;
if (frame_out->ethertype <= ETHERNET_v2_MTU) // check if the field is a length or an ethertype frame_out->length = length - ETHERNET_MAC_HEADER_LENGTH;
frame_out->length = frame_out->ethertype;
else
frame_out->length = length - ETHERNET_MAC_HEADER_LENGTH - FCS_LENGTH;
} }
U0 EthernetFrameFinish(I64 de_index) U0 EthernetFrameFinish(I64 de_index)