DMA assignment

[carlovalgocela]

In the timesys BSP User Guide BSP User Guide for Freescale TWR-VF65GS10 | Timesys Embedded Linux

Linux uses DMA channels on DMA engine 0,mux 0

     UART1 RX - Channel 4
     UART1 TX - Channel 5

     DSPI0 RX - Channel 12
     DSPI0 TX - Channel 13

     SAI2 (I2S2) RX - Channel 20
     SAI2 (I2S2) TX - Channel 21

But when i checked the in the linux  # ls -1 /sys/class/dma

I can see that there are DMA assigned on DMA1:

dma1chan0

dma1chan1

dma1chan10

dma1chan11

dma1chan12

dma1chan13

dma1chan14

I would like to ask if it is possible to reroute DMA1 to DMA0?

I want to configure the Linux to only use DMA0 and the MQX to DMA1.

[timesyssupport]

Hello Carlo,

Which kernel version is this in regards to? This is the same query in your ticket in our queue, correct?

Thank you,

Timesys Support

[carlovalgocela]

Hello timesyssupport​,

In this test, i'm using the Kernel 3.1.13.

[timesyssupport]

Hello Carlo,

Please find the attached patch, where Linux will no longer initialize DMA1. This modifies the vf610 device tree includes file, so all you need to do is apply this patch to your kernel sources, then rebuild your device tree blob for the hardware target (pcm052).

Thanks,

Timesys Support

[jackblather]

I think you meant the 3.13-x kernel.

[carlovalgocela]

Jack Blather​

Yes you are correct.

Thanks for the correction

[jackblather]

You're Welcome.

[karina_valencia]

timesyssupport​ please continue with the follow up.

[karina_valencia]

timesyssupport​ can you help to attend this case?