137 SPI+DMA

#include "bat32g137.h"
#include "sci.h"
#include "stdio.h"

// bref: spi dma发送
// para:
// note:
static void spi_send_dma(uint8_t *data,uint16_t len)
{
	#define SPI10_DMA_VECTOR   14
	#define DMA_SRAM_OFFSET    0
	
	DMAVEC->VEC[SPI10_DMA_VECTOR] = DMA_SRAM_OFFSET;
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMACR = (0 << CTRL_DMACR_SZ_Pos) | (0 << CTRL_DMACR_CHNE_Pos) |
									  (0 << CTRL_DMACR_DAMOD_Pos) | (1 << CTRL_DMACR_SAMOD_Pos) |
									  (0 << CTRL_DMACR_MODE_Pos);
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMBLS = 1;
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMACT = len - 1;
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMRLD = len - 1;
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMSAR = (uint32_t)data+1;
	DMAVEC->CTRL[DMA_SRAM_OFFSET].DMDAR = (uint32_t)&SCI0->SIO10;
	
	/* init DMA registers */
	CGC->PER1 |= CGC_PER1_DMAEN_Msk;
	DMA->DMABAR = DMAVEC_BASE;
	DMA->DMAEN1 |= (1 << 6);
	SCI0->SIO10 = *data;
	// 等待传输完成
//	INT->IF[SPI10_IRQn].IFL = 0;
//	while(INT->IF[SPI10_IRQn].IFL == 0);
	//INT->IF[SPI10_IRQn].IFL = 0;
	while(DMA->DMAEN1 & (1 << 6));
}



int main(void)
{
	spi_mode_t  mode = SPI_MODE_0;
	// 开启外设时钟
	CGC->PER0 |= CGC_PER0_SCI0EN_Msk;
	// 停止通道
    SCI0->ST0 |= _0004_SCI_CH2_STOP_TRG_ON;
	// 分频器
    SCI0->SPS0 &= ~SCI0_SPS0_PRS01_Msk;
    SCI0->SPS0 |= (0 << SCI0_SPS0_PRS01_Pos);
	// 设置为主模式
    SCI0->SIR02 = _0004_SCI_SIRMN_FECTMN | _0002_SCI_SIRMN_PECTMN | _0001_SCI_SIRMN_OVCTMN;
	// 设置为SPI模式 传输结束产生中断
    SCI0->SMR02 = _0020_SMRMN_DEFAULT_VALUE | _8000_SCI_CLOCK_SELECT_CK01 | _0000_SCI_CLOCK_MODE_CKS |
                  _0000_SCI_TRIGGER_SOFTWARE | _0000_SCI_MODE_SPI | _0001_SCI_BUFFER_EMPTY;
	// 设置SPI 极性
    SCI0->SCR02 = _0004_SCRMN_DEFAULT_VALUE | _8000_SCI_TRANSMISSION | mode | _0000_SCI_INTSRE_MASK |
                  _0000_SCI_PARITY_NONE | _0000_SCI_MSB | _0000_SCI_STOP_NONE | _0003_SCI_LENGTH_8;

	//(2+1)*2 = 6 
	// 48/6 = 8M
    SCI0->SDR02 = 2 << 9; 

    /* Set output enable */
    if ((mode == SPI_MODE_0) || (mode == SPI_MODE_1))
    {
        SCI0->SO0 &= ~_0400_SCI_CH2_CLOCK_OUTPUT_1;
    }
    if ((mode == SPI_MODE_2) || (mode == SPI_MODE_3))
    {
        SCI0->SO0 |= _0400_SCI_CH2_CLOCK_OUTPUT_1;
    }
    SCI0->SOE0 |= _0004_SCI_CH2_OUTPUT_ENABLE;
	SCI0->SO0 |= _0004_SCI_CH2_DATA_OUTPUT_1;
    SCI0->SOE0 |= _0004_SCI_CH2_OUTPUT_ENABLE;
    SCI0->SS0 |= _0004_SCI_CH2_START_TRG_ON;
//    /* Set P02/SDO10 pin */
    PORT->PMC0 &= ~(1<<2);
    PORT->P0 |= 1<<2;
    PORT->PM0 &= ~(1<<2);
    /* Set P03/SDI10 pin */
    PORT->PMC0 &= 0xF7U;
    PORT->PM0 |= 0x08U;
    /* Set P04/SCK10 pin */
    PORT->PMC0 &= 0xEFU;
    PORT->P0 |= 0x10;
    PORT->PM0 &= ~(1<<4);
	// 
	PORT->PMC0 &= ~(1<<5);
    PORT->PM0 &= ~(1<<5);
	
	PORT->P0 &=~(1<<5); 
	
	// 开启对应的中断
	 /* clear INTSPI10 interrupt flag */
    INTC_ClearPendingIRQ(SPI10_IRQn);
    NVIC_ClearPendingIRQ(SPI10_IRQn);
    /* enable INTSPI10 interrupt */
    INTC_EnableIRQ(SPI10_IRQn);
    NVIC_EnableIRQ(SPI10_IRQn);
	
	// 使能通道
	SCI0->SS0 |= _0004_SCI_CH2_START_TRG_ON;
	
	static uint8_t buff[] = {0xAA,0x55,0x12,0x34};
	while(1)
	{
		spi_send_dma(buff,sizeof(buff));
	}
}

void IRQ13_Handler(void) __attribute__((alias("spi10_interrupt")));
/***********************************************************************************************************************
* Function Name: spi10_interrupt
* Description  : None
* Arguments    : None
* Return Value : None
***********************************************************************************************************************/
void spi10_interrupt(void)
{
    volatile uint8_t err_type;
    volatile uint8_t sio_dummy;

    INTC_ClearPendingIRQ(SPI10_IRQn);
    err_type = (uint8_t)(SCI0->SSR02 & _0001_SCI_OVERRUN_ERROR);
    SCI0->SIR02 = (uint16_t)err_type;

    if (1U == err_type)
    {
        //spi10_callback_error(err_type);    /* overrun error occurs */
		
    }
    else
    {
		if(PORT->P0 & (1<<5))
		{
			PORT->P0 &=~(1<<5);
		}
		else
		{
			PORT->P0 |=(1<<5);
		}
        
    }
}

DMA需要找SPI的DMA向量位置，找一个内存设置为 DMA的信息块。

DMA机制是利用截获SPI的中断来启动DMA传输，所以可以先写一个数据启动DMA传输。

while(DMA->DMAEN1 & (1 << 6));这个意思是传输完成6 bit自动变为0.

也可以判断中断方式来确定DMA是否传输完成，由于本例子中开启了中断，所以不使用本方法判断DMA传输结束。