// -------------------------------------------------------------------------
// ethernet.c
//
//  21.12.2003, J. Ahrensfeld
//
// -------------------------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <sys/time.h>
#include <sys/types.h>

#include <libsys/libsys.h>
#include "emac.h"
#include "ethernet.h"

// -------------------------------------------------------------------------
uint32_t eth_crc32(uint32_t crc, uint8_t *pData, uint32_t len)
{
	uint32_t n;
	uint32_t crc_table[] =
	{
		0x4DBDF21C, 0x500AE278, 0x76D3D2D4, 0x6B64C2B0,
		0x3B61B38C, 0x26D6A3E8, 0x000F9344, 0x1DB88320,
		0xA005713C, 0xBDB26158, 0x9B6B51F4, 0x86DC4190,
		0xD6D930AC, 0xCB6E20C8, 0xEDB71064, 0xF0000000
	};

	for (n=0; n < len; n++)
	{
		crc = (crc >> 4) ^ crc_table[(crc ^ (pData[n] >> 0)) & 0x0F];  /* lower nibble */
		crc = (crc >> 4) ^ crc_table[(crc ^ (pData[n] >> 4)) & 0x0F];  /* upper nibble */
	}
	return crc;
}

// -------------------------------------------------------------------------
void EthInit(void)
{
}

uint8_t *Eth_pkt_create(packet_t *pPacket, uint16_t proto, uint8_t *pHwAddr_src, uint8_t *pHwAddr_dst)
{
	eth_hdr_t *pEth_hdr;

	pPacket->pData = pPacket->pkt_buf;

	pEth_hdr = (eth_hdr_t*)pPacket->pData;

	memcpy(pEth_hdr->eth_addr_src, pHwAddr_src, 6);
	memcpy(pEth_hdr->eth_addr_dst, pHwAddr_dst, 6);
	pEth_hdr->proto = proto;

	pPacket->size = sizeof(eth_hdr_t);
	pPacket->pData += pPacket->size;

	return pPacket->pData;
}

uint8_t *Eth_pkt_append(packet_t *pPacket, uint32_t size)
{
	pPacket->size += size;
	pPacket->pData += size;

	return pPacket->pData;
}

uint8_t *Eth_pkt_buffer_get(packet_t *pPacket)
{
	return pPacket->pData;
}

uint32_t Eth_pkt_send(packet_t *pPacket)
{
	volatile uint32_t *pEmac_ctrl = (uint32_t*)SYS_EMAC_TX_CTRL;
	volatile uint32_t *pEmac_size = (uint32_t*)SYS_EMAC_TX_SIZE;
	volatile uint32_t *pEmac_data = (uint32_t*)SYS_EMAC_DATA;
	uint32_t *pData = (uint32_t*)pPacket->pkt_buf;
	
	uint32_t i, num_words, num_bytes;

	num_bytes = pPacket->size;

	do
	{
		EMAC_TX_alloc(num_bytes);

	} while(!EMAC_TX_is_avail());

	num_words = num_bytes >> 2;
	if (num_bytes & 3)
		num_words++;

	while(num_words >= 8)
	{
		*pEmac_data = pData[i+0];
		*pEmac_data = pData[i+1];
		*pEmac_data = pData[i+2];
		*pEmac_data = pData[i+3];
		*pEmac_data = pData[i+4];
		*pEmac_data = pData[i+5];
		*pEmac_data = pData[i+6];
		*pEmac_data = pData[i+7];
		i += 8;
		num_words -= 8;
	}
	for (i=0; i < num_words; i++)
	{
		*pEmac_data = pData[i];
	}

	EMAC_TX_commit();

	return num_bytes;

}

uint32_t Eth_pkt_recv(uint8_t *pData)
{

	volatile uint32_t *pEmac_ctrl = (uint32_t*)SYS_EMAC_RX_CTRL;
	volatile uint32_t *pEmac_size = (uint32_t*)SYS_EMAC_RX_SIZE;
	volatile uint32_t *pEmac_data = (uint32_t*)SYS_EMAC_DATA;

	uint32_t i, num_words, num_bytes;
	
	if(EMAC_RX_is_avail())
	{

		if (EMAC_RX_is_valid())
		{
//			if ((*pEmac_ctrl & EMAC_RX_STAT_PKT_BCAST))
//			{
//				printf("Packet broad cast!\n");
//			}

			num_bytes = EMAC_RX_get_size();
			num_words = num_bytes >> 2;
			if (num_bytes & 3)
				num_words++;

			EMAC_RX_request();
			for (i=0; i < num_words; i++)
			{
				 ((uint32_t*)pData)[i] = *pEmac_data;
			}

			EMAC_RX_free();
		}
	}
	return num_bytes;
}

uint16_t htons(uint16_t a)
{
	return HTONS(a);
}