#ifndef __ETHERNETIF_H
#define __ETHERNETIF_H

#include "lwip/err.h"
#include "lwip/netif.h"

/* Unique device ID */
#define ROM_CFG_USERADR_ID 0x1FFFF7E8

/* Ethernet Frame Size Definitions */
#define ETH_HEADER \
  14                /* 6 byte Dest addr, 6 byte Src addr, 2 byte length/type */
#define ETH_CRC 4   /* Ethernet CRC */
#define ETH_EXTRA 2 /* Extra bytes in some cases */
#define VLAN_TAG 4  /* optional 802.1q VLAN Tag */

#define MIN_ETH_PAYLOAD 46   /* Minimum Ethernet payload size */
#define MAX_ETH_PAYLOAD 1500 /* Maximum Ethernet payload size */

#define ETH_MAX_PACKET_SIZE \
  1536 /* ETH_HEADER + VLAN_TAG + MAX_ETH_PAYLOAD + ETH_CRC */
#define MIN_ETH_FRAME_SIZE (ETH_HEADER + MIN_ETH_PAYLOAD) /* 60 bytes */

/* Buffer Configuration */
#define ETH_RX_BUF_COUNT 4
#define ETH_TX_BUF_COUNT 2
#define ETH_RX_BUF_SIZE ETH_MAX_PACKET_SIZE
#define ETH_TX_BUF_SIZE ETH_MAX_PACKET_SIZE

/* DMA descriptor stuff */
#define ETH_DMARxDesc_FrameLengthShift 16

typedef struct {
  uint32_t volatile Status;     /* Status */
  uint32_t ControlBufferSize;   /* Control and Buffer1, Buffer2 lengths */
  uint32_t Buffer1Addr;         /* Buffer1 address pointer */
  uint32_t Buffer2NextDescAddr; /* Buffer2 or next descriptor address pointer */
} ETH_DMADESCTypeDef;

/**
 * Should be called at the beginning of the program to set up the
 * network interface. It calls the function low_level_init() to do the
 * actual setup of the hardware.
 *
 * This function should be passed as a parameter to netif_add().
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return ERR_OK if the loopif is initialized
 *         ERR_MEM if private data couldn't be allocated
 *         any other err_t on error
 */
err_t ethernetif_init(struct netif* netif);

/**
 * This function should be called when a packet is ready to be read
 * from the interface. It uses the function low_level_input() that
 * should handle the actual reception of bytes from the network
 * interface. Then the type of the received packet is determined and
 * the appropriate input function is called.
 *
 * @param netif the lwip network interface structure for this ethernetif
 */
void ethernetif_input(struct netif* netif);

/**
 * This function should be called periodically from the main loop
 * to check the link status and update lwIP accordingly.
 *
 * @param netif the lwip network interface structure for this ethernetif
 */
void ethernetif_link_poll(struct netif* netif);

/**
 * Write a value to PHY register.
 *
 * @param reg_add PHY register address.
 * @param reg_val Value to write.
 */
void phy_write_reg(uint8_t reg_add, uint16_t reg_val);

/**
 * Read a value from PHY register.
 *
 * @param reg_add PHY register address.
 * @return Register value.
 */
uint16_t phy_read_reg(uint8_t reg_add);

#endif /* __ETHERNETIF_H */