a question of mpc8313, maybe simple

Scott Wood scottwood at freescale.com
Tue Jun 24 03:09:56 EST 2008


On Mon, Jun 23, 2008 at 05:48:07AM -0700, jumpingProgrammer wrote:
> i am working with a board of mpc8313 using default mpc8313erdb.dts.
> But i do not know how can i correctly use DMA to transport data from memory
> to a PCI device.
> i tryed this
> {
>      .....
>      request_irq(IRQ,....);
>      request_dma(.....);
>      ....
> }
> 
> In request_irq() , i do not know what is the parameter IRQ.

Use pci_dev->irq.

> And , i did not find any words about DMA in mpc8313erdb.dts .

PCI devices can do bus-mastering DMA themselves; request_dma() is for ISA
devices.

-Scott



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