/**
* @file
* Ethernet Interface Skeleton
*
*/

/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
*    this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
*    this list of conditions and the following disclaimer in the documentation
*    and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
*    derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/

#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/timeouts.h"
#include "netif/etharp.h"
#include "err.h"
#include "ethernetif.h"

#include "main.h"
#include "gd32h7xx_enet.h"
#include <string.h>
#include "semphr.h"
#include "app_init/app_init.h"

/* EthIf 任务栈与优先级与 CCU601E_D 一致：取自 my_task_data[TASK_ID_EthIf]，禁止硬编码 350
 *（字），否则栈过小，经 tcpip_input 入栈易 HardFault，表现为“程序不跑”。 */
#define LOWLEVEL_OUTPUT_WAITING_TIME              (250)
/* The time to block waiting for input */
#define LOWLEVEL_INPUT_WAITING_TIME               ((portTickType )100)
/* define those to better describe your network interface */
#define IFNAME0 'G'
#define IFNAME1 'D'

/* ENET RxDMA/TxDMA descriptor */
extern enet_descriptors_struct  rxdesc_tab[ENET_RXBUF_NUM], txdesc_tab[ENET_TXBUF_NUM];

/* ENET receive buffer  */
extern uint8_t rx_buff[ENET_RXBUF_NUM][ENET_RXBUF_SIZE];

/* ENET transmit buffer */
extern uint8_t tx_buff[ENET_TXBUF_NUM][ENET_TXBUF_SIZE];

/*global transmit and receive descriptors pointers */
extern enet_descriptors_struct  *dma_current_txdesc;
extern enet_descriptors_struct  *dma_current_rxdesc;

/* preserve another ENET RxDMA/TxDMA ptp descriptor for normal mode */
enet_descriptors_struct  ptp_txstructure[ENET_TXBUF_NUM];
enet_descriptors_struct  ptp_rxstructure[ENET_RXBUF_NUM];


static struct netif *low_netif = NULL;
xSemaphoreHandle g_rx_semaphore = NULL;

/**
* In this function, the hardware should be initialized.
* Called from ethernetif_init().
*
* @param netif the already initialized lwip network interface structure
*        for this ethernetif
*/
static void low_level_init(struct netif *netif)
{
    uint32_t i;

    /* set netif MAC hardware address length */
    netif->hwaddr_len = ETHARP_HWADDR_LEN;

    /* set netif MAC hardware address */
    netif->hwaddr[0] =  BOARD_MAC_ADDR0;
    netif->hwaddr[1] =  BOARD_MAC_ADDR1;
    netif->hwaddr[2] =  BOARD_MAC_ADDR2;
    netif->hwaddr[3] =  BOARD_MAC_ADDR3;
    netif->hwaddr[4] =  BOARD_MAC_ADDR4;
    netif->hwaddr[5] =  BOARD_MAC_ADDR5;

    /* set netif maximum transfer unit */
    netif->mtu = 1500;

    /* accept broadcast address and ARP traffic */
    netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;

    low_netif = netif;

    /* create binary semaphore used for informing ethernetif of frame reception */
    if(g_rx_semaphore == NULL) {
        vSemaphoreCreateBinary(g_rx_semaphore);
        xSemaphoreTake(g_rx_semaphore, 0);
    }

#ifdef USE_ENET0
    /* initialize MAC address in ethernet MAC */
    enet_mac_address_set(ENET0, ENET_MAC_ADDRESS0, netif->hwaddr);
#endif /* USE_ENET0 */
#ifdef USE_ENET1
    /* initialize MAC address in ethernet MAC */
    enet_mac_address_set(ENET1, ENET_MAC_ADDRESS0, netif->hwaddr);
#endif /* USE_ENET1 */

#ifdef USE_ENET0
    /* initialize descriptors list: chain/ring mode */
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
    enet_ptp_enhanced_descriptors_chain_init(ENET0, ENET_DMA_TX);
    enet_ptp_enhanced_descriptors_chain_init(ENET0, ENET_DMA_RX);
#else
    enet_descriptors_chain_init(ENET0, ENET_DMA_TX);
    enet_descriptors_chain_init(ENET0, ENET_DMA_RX);

//    enet_descriptors_ring_init(ENET0, ENET_DMA_TX);
//    enet_descriptors_ring_init(ENET0, ENET_DMA_RX);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET0 */

#ifdef USE_ENET1
    /* initialize descriptors list: chain/ring mode */
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
    enet_ptp_enhanced_descriptors_chain_init(ENET1, ENET_DMA_TX);
    enet_ptp_enhanced_descriptors_chain_init(ENET1, ENET_DMA_RX);
#else
    enet_descriptors_chain_init(ENET1, ENET_DMA_TX);
    enet_descriptors_chain_init(ENET1, ENET_DMA_RX);

//    enet_descriptors_ring_init(ENET1, ENET_DMA_TX);
//    enet_descriptors_ring_init(ENET1, ENET_DMA_RX);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET1 */

    /* enable ethernet Rx interrrupt */
    {
        int i;
        for(i = 0; i < ENET_RXBUF_NUM; i++) {
            enet_rx_desc_immediate_receive_complete_interrupt(&rxdesc_tab[i]);
        }
    }


#ifdef CHECKSUM_BY_HARDWARE
    /* enable the TCP, UDP and ICMP checksum insertion for the Tx frames */
    for(i = 0; i < ENET_TXBUF_NUM; i++) {
        enet_transmit_checksum_config(&txdesc_tab[i], ENET_CHECKSUM_TCPUDPICMP_FULL);
    }
#endif /* CHECKSUM_BY_HARDWARE */

    /* EthIf：与 CCU601E_D ethernetif.c 相同，用任务表栈/优先级创建 */
    (void)MY_TASK_NEW(TASK_ID_EthIf, ethernetif_input, (void *)netif);

    /* enable MAC and DMA transmission and reception */
#ifdef USE_ENET0
    /* enable MAC and DMA transmission and reception */
    enet_enable(ENET0);
#endif /* USE_ENET0 */

#ifdef USE_ENET1
    /* enable MAC and DMA transmission and reception */
    enet_enable(ENET1);
#endif /* USE_ENET1 */
}


/**
* This function should do the actual transmission of the packet. The packet is
* contained in the pbuf that is passed to the function. This pbuf
* might be chained.
*
* @param netif the lwip network interface structure for this ethernetif
* @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
* @return ERR_OK if the packet could be sent
*         an err_t value if the packet couldn't be sent
*
* @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
*       strange results. You might consider waiting for space in the DMA queue
*       to become availale since the stack doesn't retry to send a packet
*       dropped because of memory failure (except for the TCP timers).
*/

static err_t low_level_output(struct netif *netif, struct pbuf *p)
{
    static xSemaphoreHandle s_tx_semaphore = NULL;
    struct pbuf *q;
    uint8_t *buffer ;
    uint16_t framelength = 0;
    ErrStatus reval = ERROR;
    uint32_t wait_guard;

    SYS_ARCH_DECL_PROTECT(sr);

    if(s_tx_semaphore == NULL) {
        vSemaphoreCreateBinary(s_tx_semaphore);
    }

    if (xSemaphoreTake(s_tx_semaphore, LOWLEVEL_OUTPUT_WAITING_TIME) == pdTRUE) {
        SYS_ARCH_PROTECT(sr);

        /* 避免死等：若 DMA 描述符长期不可用，返回 ERR_TIMEOUT，不能卡死 tcpip 线程 */
        wait_guard = 0U;
        while (((uint32_t)RESET != (dma_current_txdesc->status & ENET_TDES0_DAV)) && (wait_guard < 1000000U)) {
            wait_guard++;
        }
        if (wait_guard >= 1000000U) {
            SYS_ARCH_UNPROTECT(sr);
            (void)xSemaphoreGive(s_tx_semaphore);
            return ERR_TIMEOUT;
        }

#ifdef USE_ENET0
        buffer = (uint8_t *)(enet_desc_information_get(ENET0, dma_current_txdesc, TXDESC_BUFFER_1_ADDR));
#endif /* USE_ENET0 */

#ifdef USE_ENET1
        buffer = (uint8_t *)(enet_desc_information_get(ENET1, dma_current_txdesc, TXDESC_BUFFER_1_ADDR));
#endif /* USE_ENET1 */

        for(q = p; q != NULL; q = q->next) {
            memcpy((uint8_t *)&buffer[framelength], q->payload, q->len);
            framelength = framelength + q->len;
        }

#ifdef USE_ENET0
        /* transmit descriptors to give to DMA */
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
        reval = ENET_NOCOPY_PTPFRAME_TRANSMIT_ENHANCED_MODE(ENET0, framelength, NULL);
#else
        reval = ENET_NOCOPY_FRAME_TRANSMIT(ENET0, framelength);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET0 */

#ifdef USE_ENET1
        /* transmit descriptors to give to DMA */
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
        reval = ENET_NOCOPY_PTPFRAME_TRANSMIT_ENHANCED_MODE(ENET1, ramelength, NULL);
#else
        reval = ENET_NOCOPY_FRAME_TRANSMIT(ENET1, framelength);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET1 */
        SYS_ARCH_UNPROTECT(sr);

        /* give semaphore and exit */
        xSemaphoreGive(s_tx_semaphore);
    }

    if (SUCCESS == reval) {
        return ERR_OK;
    }
    /* 发送失败不能死循环，否则会卡死 tcpip 线程导致运行灯停 */
    return ERR_IF;

}

/**
* Should allocate a pbuf and transfer the bytes of the incoming
* packet from the interface into the pbuf.
*
* @param netif the lwip network interface structure for this ethernetif
* @return a pbuf filled with the received packet (including MAC header)
*         NULL on memory error
*/
static struct pbuf *low_level_input(struct netif *netif)
{
    struct pbuf *p = NULL, *q;
    uint32_t l = 0;
    u16_t len;
    uint8_t *buffer;

    (void)netif; /* 单网口时仍用全局 DMA 描述符，与参考工程行为一致 */

#ifdef USE_ENET0
    /* obtain the size of the packet and put it into the "len" variable. */
    len = enet_desc_information_get(ENET0, dma_current_rxdesc, RXDESC_FRAME_LENGTH);
    buffer = (uint8_t *)(enet_desc_information_get(ENET0, dma_current_rxdesc, RXDESC_BUFFER_1_ADDR));
#endif /* USE_ENET0 */

#ifdef USE_ENET1
    /* obtain the size of the packet and put it into the "len" variable. */
    len = enet_desc_information_get(ENET1, dma_current_rxdesc, RXDESC_FRAME_LENGTH);
    buffer = (uint8_t *)(enet_desc_information_get(ENET1, dma_current_rxdesc, RXDESC_BUFFER_1_ADDR));
#endif /* USE_ENET1 */

    if(len > 0) {
        /* We allocate a pbuf chain of pbufs from the Lwip buffer pool */
        p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
    }

    if(p != NULL) {
        for(q = p; q != NULL; q = q->next) {
            memcpy((uint8_t *)q->payload, (u8_t *)&buffer[l], q->len);
            l = l + q->len;
        }
    }
#ifdef USE_ENET0
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
    ENET_NOCOPY_PTPFRAME_RECEIVE_ENHANCED_MODE(ENET0, NULL);
#else
    ENET_NOCOPY_FRAME_RECEIVE(ENET0);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET0 */

#ifdef USE_ENET1
#ifdef SELECT_DESCRIPTORS_ENHANCED_MODE
    ENET_NOCOPY_PTPFRAME_RECEIVE_ENHANCED_MODE(ENET1, NULL);
#else
    ENET_NOCOPY_FRAME_RECEIVE(ENET1);
#endif /* SELECT_DESCRIPTORS_ENHANCED_MODE */
#endif /* USE_ENET1 */

    return p;
}


/**
* This function is the ethernetif_input task, it is processed 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(void *pvParameters)
{
    struct pbuf *p;
    struct netif *netif;
    BaseType_t rx_event = pdFALSE;
    SYS_ARCH_DECL_PROTECT(sr);

    netif = (struct netif *)pvParameters;
    if (netif == NULL) {
        netif = low_netif;
    }

    for (;;) {
        rx_event = xSemaphoreTake(g_rx_semaphore, LOWLEVEL_INPUT_WAITING_TIME);

#if (ENET_RX_FALLBACK_POLLING == 0)
        if (rx_event != pdTRUE) {
            continue;
        }
#endif

TRY_GET_NEXT_FRAME:
        SYS_ARCH_PROTECT(sr);
        p = low_level_input(netif);
        SYS_ARCH_UNPROTECT(sr);

        if (p != NULL) {
            if (ERR_OK != netif->input(p, netif)) {
                pbuf_free(p);
            } else {
                goto TRY_GET_NEXT_FRAME;
            }
        }

        /* 当 ENET_RX_FALLBACK_POLLING=1 时，超时后也会进入一次兜底轮询 */
        LWIP_UNUSED_ARG(rx_event);
    }
}

/**
* 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)
{
    LWIP_ASSERT("netif != NULL", (netif != NULL));

#if LWIP_NETIF_HOSTNAME
    /* initialize interface hostname */
    netif->hostname = "lwip";
#endif /* LWIP_NETIF_HOSTNAME */

    netif->name[0] = IFNAME0;
    netif->name[1] = IFNAME1;

    netif->output = etharp_output;
    netif->linkoutput = low_level_output;

    /* initialize the hardware */
    low_level_init(netif);

    return ERR_OK;
}