All, I have a Freescale P2020 Reference Design Board. I am investigating the possibility of using the dmaengine capability in the 2.6.32.13 kernel to transfer data from memory out onto the PCIe bus. As a first step, I thought I would try the DMA test client (dmatest.ko) to make sure the dmaengine was functioning. I know this doesn't transfer anything over PCIe but only transfers from one memory buffer to another, but I figured I need to get this working first. Anyway I built dmatest.ko and ran it (with insmod), and discovered it didn't do anything. I added some printk's to the kernel to investigate what was going on and I found that all attempts to find a channel within dma_request_channel were unsuccessful. Three of the channels were not used because they were already publicly allocated. One channel was not used because it didn't have DMA_MEMCPY capability.
Here are my questions then: 1. Is the dmaengine the appropriate method to use for transferring data from memory out onto the PCIe bus? 2. If dmaengine is correct, what can I do to free up a channel for my own use? Thank you. Chuck _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
