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!
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