hi,all.
I am using SPI2 to access a SPI Flash for my application, the source is changed from kernel 2.6.32-17(DVSDK4.0).
But I found the EDMA only send ONE byte ,and never send again.
the charlen=8.
From datasheet, DMA rx and tx channel for SPI2 is 11 and 10, but I donot know how to set the EVENTQ. For SPI0 it is 3.
I use the code following to allocate DMA:
edma_alloc_channel(11,davinci_spi_dma_rx_callback, mydata, davinci_spi_dma->eventq);
if (r < 0) {
DBG("Unable to request DMA channel for MibSPI RX\n");
return -EAGAIN;
}
davinci_spi_dma->dma_rx_channel = r;
r = edma_alloc_channel(10,davinci_spi_dma_tx_callback,mydata,davinci_spi_dma->eventq);
if (r < 0) {
edma_free_channel(davinci_spi_dma->dma_rx_channel);
davinci_spi_dma->dma_rx_channel = -1;
DBG("Unable to request DMA channel for MibSPI TX\n");
return -EAGAIN;
}
davinci_spi_dma->dma_tx_channel = r;
and it seems OK.
So i start DMA by these:
count=8,data_type=1,
edma_set_transfer_params(davinci_spi_dma->dma_tx_channel, data_type, count, 1, 0, ASYNC); edma_set_dest(davinci_spi_dma->dma_tx_channel, tx_reg, INCR, W8BIT); /*not fifo!*/ edma_set_src(davinci_spi_dma->dma_tx_channel, spix->tx_dma_addr, INCR, W8BIT); edma_set_src_index(davinci_spi_dma->dma_tx_channel, data_type, 0); edma_set_dest_index(davinci_spi_dma->dma_tx_channel, 0, 0); edma_start(davinci_spi_dma->dma_tx_channel); davinci_spi_set_dma_req(spix, 1); // But the DMA only send ONE byte ,and never send more data again. Someone has tips?Thanks!
