SC59x UART Tx DMA

Hi

I'm trying to use a UART on a Sharc core using DMA so I can send strings of data in the background.  I have been able to configure the UART to transmit using core register access, but having difficulty getting a small DMA test function working.  My code is below.  The ARM just calls adi_gic_Init() before enabling the Sharc.

My code should output '[Hello][world!]', but only outputs '[][]' which are done using core access of the UART.

Can you point me towards where I'm going wrong?

Thanks

Howard

#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include "services/int/adi_sec.h"
#include "services/int/adi_int.h"
#include "platform_include.h"
#include "ADSP-SC59x_typedefs.h"


void uart_init(void) {

 /* Use UART 0 for testing
 * UART0_TX = PA_06 (multiplexed function 1)
 * UART0_RX = PA_07 (multiplexed function 1)
 */

 ADI_SPU_SECUREP_t secure_peripheral_reg;
 secure_peripheral_reg.VALUE32 = 0;
 secure_peripheral_reg.SSEC = 1;
 secure_peripheral_reg.MSEC = 1;
 *pREG_SPU0_SECUREP29 = secure_peripheral_reg.VALUE32; /* UART0 */

 ADI_PORT_FER_SET_t port_func_set;
 port_func_set.VALUE32 = 0;
 port_func_set.PX6 = 1;
 port_func_set.PX7 = 1;
 *pREG_PORTA_FER_SET = port_func_set.VALUE32;

 ADI_PORT_MUX_t port_mux;
 port_mux.VALUE32 = 0;
 port_mux.MUX6 = 1;
 port_mux.MUX7 = 1;
 *pREG_PORTA_MUX = port_mux.VALUE32;

 /* Set baud rate to 300 - looks like SCLK0 is 125 MHz, not 100MHz as hinted in Hardware reference manual */
 ADI_UART_CLK_t uart_clk;
 uart_clk.VALUE32 = 0;
 uart_clk.EDBO = UART_CLK_DIS_DIV_BY_ONE;
 uart_clk.DIV = 26041;
 *pREG_UART0_CLK = uart_clk.VALUE32;

 ADI_UART_CTL_t uart_ctl;
 uart_ctl.VALUE32 = 0;
 uart_ctl.EN = UART_CTL_CLK_EN;
 uart_ctl.MOD = UART_CTL_UART_MODE;
 uart_ctl.WLS = UART_CTL_WL8BITS;
 *pREG_UART0_CTL = uart_ctl.VALUE32;

 *pREG_DMA20_STAT = 0xffffffff;
 *pREG_DMA20_CFG = 0;
 *pREG_DMA20_DSCPTR_NXT = 0;
 *pREG_DMA20_ADDRSTART = 0;
 *pREG_DMA20_XCNT = 0;
 *pREG_DMA20_XMOD = 0;
 *pREG_DMA20_YCNT = 0;
 *pREG_DMA20_YMOD = 0;

 adi_int_ClearPending(INTR_UART0_TXDMA);

}

void uart_print(const char * p_str) {

 while ((*pREG_UART0_STAT & (1<<5)) == 0) {
 ;
 }
 *pREG_UART0_THR = '[';

/*
 * From page 22-24 of SC592 HRM
 *
 * 1. Make sure that the UART_IMSK.ETBEI or the UART_IMSK.ERBFI bits are cleared before configuring the DMA.
 * 2. Configure the dedicated DMA channel.
 * 3. Set the UART_IMSK.ETBEI or UART_IMSK.ERBFI bits to start the transfer.
 *
 * From page 34-4 of SC592 HRM
 *
 * DMA20 UART0_TXDMA UART0 Transmit DMA
 */

 ADI_UART_IMSK_CLR_t uart_imsk_clr;
 uart_imsk_clr.VALUE32 = 0;
 uart_imsk_clr.ETBEI = UART_IMSK_ETBEI_HI;
 *pREG_UART0_IMSK_CLR = uart_imsk_clr.VALUE32;

 ADI_DMA_CFG0_CFG_t dma_cfg;
 dma_cfg.VALUE32 = 0;
 dma_cfg.EN = DMA_CFG_EN;
 dma_cfg.WNR = DMA_CFG_READ;
 dma_cfg.PSIZE = DMA_CFG_PSIZE01;
 dma_cfg.MSIZE = DMA_CFG_MSIZE01;
 dma_cfg.FLOW = DMA_CFG_STOP;
 dma_cfg.INT = DMA_CFG_XCNT_INT;
 dma_cfg.TWOD = DMA_CFG_ADDR1D;

 *pREG_DMA20_CFG = 0;
 *pREG_DMA20_ADDRSTART = (uint32_t *)p_str;
 *pREG_DMA20_XCNT = strlen(p_str);
 *pREG_DMA20_XMOD = 1;
 *pREG_DMA20_CFG = dma_cfg.VALUE32;

 ADI_UART_IMSK_SET_t uart_imsk_set;
 uart_imsk_set.VALUE32 = 0;
 uart_imsk_set.ETBEI = UART_IMSK_ETBEI_HI;
 *pREG_UART0_IMSK_SET = uart_imsk_set.VALUE32;

 while ((*pREG_UART0_STAT & (1<<5)) == 0) {
 ;
 }
 *pREG_UART0_THR = ']';
 
 adi_uart_DMAWrite()

 return;
}


int main(int argc, char *argv[]) {

 if (adi_sec_Init() != ADI_SEC_SUCCESS) {
 return 1;
 }

 uart_init();
 uart_print("Hello");
 uart_print("world!");

 return 0;
}