/*
* initEdma() - Initialize the DMA controller. Use linked transfers to
* automatically transition from ping to pong and visa-versa.
*/
void initEdma(void)
{
/* Configure transmit channel */
hEdmaXmt = EDMA_open(EDMA_CHA_XEVT1, EDMA_OPEN_RESET); // get hEdmaXmt handle and reset channel
hEdmaReloadXmtPing = EDMA_allocTable(-1); // get hEdmaReloadXmtPing handle
hEdmaReloadXmtPong = EDMA_allocTable(-1); // get hEdmaReloadXmtPong handle
gEdmaConfigXmt.dst = MCBSP_getXmtAddr(hMcbsp1); // set the desination address to McBSP1 DXR
gXmtChan = EDMA_intAlloc(-1); // get an open TCC
gEdmaConfigXmt.opt |= EDMA_FMK(OPT,TCC,gXmtChan); // set TCC to gXmtChan
EDMA_config(hEdmaXmt, &gEdmaConfigXmt); // then configure the registers
EDMA_config(hEdmaReloadXmtPing, &gEdmaConfigXmt); // and the reload for Ping
gEdmaConfigXmt.src = EDMA_SRC_OF(gBufferXmtPong); // change the structure to have a source of Pong
EDMA_config(hEdmaReloadXmtPong, &gEdmaConfigXmt); // and configure the reload for Pong
EDMA_link(hEdmaXmt,hEdmaReloadXmtPong); // link the regs to Pong
EDMA_link(hEdmaReloadXmtPong,hEdmaReloadXmtPing); // link Pong to Ping
EDMA_link(hEdmaReloadXmtPing,hEdmaReloadXmtPong); // and link Ping to Pong
/* Configure receive channel */
hEdmaRcv = EDMA_open(EDMA_CHA_REVT1, EDMA_OPEN_RESET); // get hEdmaRcv handle and reset channel
hEdmaReloadRcvPing = EDMA_allocTable(-1); // get hEdmaReloadRcvPing handle
hEdmaReloadRcvPong = EDMA_allocTable(-1); // get hEdmaReloadRcvPong handle
gEdmaConfigRcv.src = MCBSP_getRcvAddr(hMcbsp1); // and the desination address to McBSP1 DXR
gRcvChan = EDMA_intAlloc(-1); // get an open TCC
gEdmaConfigRcv.opt |= EDMA_FMK(OPT,TCC,gRcvChan); // set TCC to gRcvChan
EDMA_config(hEdmaRcv, &gEdmaConfigRcv); // then configure the registers
EDMA_config(hEdmaReloadRcvPing, &gEdmaConfigRcv); // and the reload for Ping
gEdmaConfigRcv.dst = EDMA_DST_OF(gBufferRcvPong); // change the structure to have a destination of Pong
EDMA_config(hEdmaReloadRcvPong, &gEdmaConfigRcv); // and configure the reload for Pong
EDMA_link(hEdmaRcv,hEdmaReloadRcvPong); // link the regs to Pong
EDMA_link(hEdmaReloadRcvPong,hEdmaReloadRcvPing); // link Pong to Ping
EDMA_link(hEdmaReloadRcvPing,hEdmaReloadRcvPong); // and link Ping to Pong
/* Enable interrupts in the EDMA controller */
EDMA_intClear(gXmtChan);
EDMA_intClear(gRcvChan); // clear any possible spurious interrupts
EDMA_intEnable(gXmtChan); // enable EDMA interrupts (CIER)
EDMA_intEnable(gRcvChan); // enable EDMA interrupts (CIER)
EDMA_enableChannel(hEdmaXmt); // enable EDMA channel
EDMA_enableChannel(hEdmaRcv); // enable EDMA channel
/* Do a dummy write to generate the first McBSP transmit event */
MCBSP_write(hMcbsp1, 0);
}
/*
* EDMA receive channel config
*/
EDMA_Config gEdmaRcvConfig = {
EDMA_OPT_RMK(
EDMA_OPT_PRI_LOW,
EDMA_OPT_ESIZE_32BIT,
EDMA_OPT_2DS_NO,
EDMA_OPT_SUM_NONE, // no source address update
EDMA_OPT_2DD_NO,
EDMA_OPT_DUM_INC, // increment destination address
EDMA_OPT_TCINT_YES, // Source address update mode
EDMA_OPT_TCC_DEFAULT,
EDMA_OPT_LINK_YES,
EDMA_OPT_FS_NO), // Frame synchronisation, we copy element by element
EDMA_SRC_OF(0x00000000), // EDMA Channel Source Address
EDMA_CNT_RMK(0, 108), // Frame count (FRMCNT), Element count (FRMCNT)
EDMA_DST_OF((Uint32) &gRcvBufferA), // EDMA Channel Destination Address
EDMA_IDX_RMK(EDMA_IDX_FRMIDX_DEFAULT, EDMA_IDX_ELEIDX_DEFAULT), // Frame index, Element index
EDMA_RLD_RMK(0x0000, 0x0000) // Element count reload, Link address
};
/*
* EDMA transmit channel config
*/
EDMA_Config gEdmaXmtConfig = {
EDMA_OPT_RMK(
EDMA_OPT_PRI_LOW,
EDMA_OPT_ESIZE_32BIT,
EDMA_OPT_2DS_NO,
EDMA_OPT_SUM_INC, // increment source address