Does the DMA Buffer Size should be same as UART FIFO size?

Posted by ddpd on Stack Overflow See other posts from Stack Overflow or by ddpd
Published on 2014-06-12T09:21:08Z Indexed on 2014/06/12 9:24 UTC
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linux-device-driver

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uart

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dma

I have written a driver for a UART in omap4460 panda board running on Linux platform.I have enabled DMA in FIFO mode in UART.My user application transfers 100 bytes of data from user space to kernel buffer(DMA buffer).

As soon as the DMA channel is enabled, data from DMA buffer is copied to FIFO which is then transmitted to TSR of UART.Since my FIFO size is 64bytes,only 64 bytes is transmitted to TSR.

What should I do to transfer remaining bytes from DMA buffer to FIFO?/ IS there any overflow occuring?

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