#include <stdint.h>
// #include "uart.h"
// #include "gpio.h"
// #include "timer.h"

volatile uint32_t *cdr_0_tx_status = (uint32_t*)( 0x40000000 + 0x0 ); //read
volatile uint32_t *cdr_0_tx_txLen  = (uint32_t*)( 0x40000000 + 0x4 ); //write
volatile uint32_t *cdr_0_tx_txFifo = (uint32_t*)( 0x40000000 + 0x8 ); //write

volatile uint32_t *cdr_0_rx_softReset = (uint32_t*)( 0x40000000 + 0x10 ); //write
volatile uint32_t *cdr_0_rx_status    = (uint32_t*)( 0x40000000 + 0x14 ); //read
volatile uint32_t *cdr_0_rx_rxLen     = (uint32_t*)( 0x40000000 + 0x18 ); //read
volatile uint32_t *cdr_0_rx_rxFifo    = (uint32_t*)( 0x40000000 + 0x1c ); //read

volatile uint32_t *cdr_1_tx_status = (uint32_t*)( 0x40000080 + 0x0 ); //read
volatile uint32_t *cdr_1_tx_txLen  = (uint32_t*)( 0x40000080 + 0x4 ); //write
volatile uint32_t *cdr_1_tx_txFifo = (uint32_t*)( 0x40000080 + 0x8 ); //write

volatile uint32_t *cdr_1_rx_softReset = (uint32_t*)( 0x40000080 + 0x10 ); //write
volatile uint32_t *cdr_1_rx_status    = (uint32_t*)( 0x40000080 + 0x14 ); //read
volatile uint32_t *cdr_1_rx_rxLen     = (uint32_t*)( 0x40000080 + 0x18 ); //read
volatile uint32_t *cdr_1_rx_rxFifo    = (uint32_t*)( 0x40000080 + 0x1c ); //read

volatile uint32_t *WriteGpio        = (uint32_t*) ( 0x60000000);
volatile uint32_t *ReadGpio         = (uint32_t*) ( 0x60000000);
volatile uint32_t *ReadIsLast       = (uint32_t*) ( 0x60000008);


static inline void error() {
    while(1);
}




void main()
{
	uint32_t readDat;
	uint8_t operator;
	uint16_t downRecvLen;
	uint16_t upRecvLen;

	uint8_t slvNum;
	uint8_t totNum;

	while(1){

		asm volatile (
			"1:\n"
			"beqz sp, 1b\n"
			"li ra, 1\n"
			"sub sp, sp, ra\n"
		);

		readDat = *cdr_0_rx_rxFifo;
		operator = (readDat >> 16) & 0xf;
		downRecvLen = readDat >> 24;

			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);

		readDat = *cdr_0_rx_rxFifo;

		if( operator == 0 ){
			slvNum = 64 - ( downRecvLen >> 3 );

			uint16_t localLen = 8;
			uint16_t downSendLen = downRecvLen - 8;

			//接收本地包
			for( uint8_t i = 0; i < 8/4; i++ ){
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);
				readDat = *cdr_0_rx_rxFifo;
			}

			// 下行包头
			*cdr_0_tx_txLen = downRecvLen; //downSendLen + 8
			*cdr_0_tx_txFifo = (downSendLen << 24) |( 0 << 16) | 0;
			*cdr_0_tx_txFifo = 0;

			//下行负载
			for( uint16_t i = 0; i < (downSendLen >> 3); i++ ){ //一次传4byte
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);
				*cdr_0_tx_txFifo = *cdr_0_rx_rxFifo; //接收即发送			
			}

			//CRC
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);
			uint32_t crc = *cdr_0_rx_rxFifo; //CRC

			asm volatile (    //等待发送完成标志
				"1:\n"
				"andi ra, x4, 0x4\n"
				"beqz x4, 1b\n"
			);

			asm volatile (
				"beqz sp, 2f\n"
				"1:"
				"j 1b\n"
				"2:\n"
			);


			//上行转发

			//接收第一个包
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);

			readDat = *cdr_1_rx_rxFifo;
			operator = (readDat >> 16) & 0xf;
			upRecvLen = readDat >> 24;
			totNum = slvNum + (upRecvLen >> 3) - 1;

			//接收第二个包
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);
			readDat = *cdr_1_rx_rxFifo;

			//发送上行包头
			*cdr_1_tx_txLen = upRecvLen + 16; //downSendLen + 8
			*cdr_1_tx_txFifo = ((upRecvLen + 8) << 24) |( 0 << 16) | 0;
			*cdr_1_tx_txFifo = 0;

			for( uint8_t i = 0; i < 8/4; i ++ ){
				*cdr_1_tx_txFifo = 0;
			}

			for( uint16_t i = 0; i < upRecvLen >> 3; i ++ ){ //一次传4byte
				asm volatile (
					"1:\n"

					"andi ra, x4, 0x40\n"
					"beqz ra, 3f\n"

					"2:\n"
					"lui ra, %hi(0x40000000)\n"
					"lw ra, 0x80(ra)\n"
					"andi ra, ra, 0x20\n"
					"bnez ra, 2b\n"

					"3:\n"
					"beqz sp, 1b\n"
					"addi sp, sp, -1\n"
				);

				*cdr_1_tx_txFifo = *cdr_1_rx_rxFifo; //接收即发送
			}

			//CRC
			asm volatile (
				"1:\n"
				"beqz sp, 1b\n"
				"addi sp, sp, -1\n"
			);
			crc = *cdr_1_rx_rxFifo; //CRC
			asm volatile (
				"beqz sp, 2f\n"
				"1:"
				"j 1b\n"
				"2:\n"
			);

		} else if ( operator == 1 ){
			error();
		} else if ( operator == 2 ){
			error();
		} else {
			error();
		}		
	}



}