Re: [irda-users] [PATCH] Make VLSI FIR depend on X86

From: Martin Diehl
Date: Tue Oct 21 2003 - 02:19:33 EST


On Mon, 20 Oct 2003, David S. Miller wrote:

> On Mon, 20 Oct 2003 19:30:33 +0200 (CEST)
> Martin Diehl <lists@xxxxxxxxx> wrote:
>
> > Well, it would work with any arch, _if_ there was a way to sync the
> > streaming pci dma buffers before giving them back to hardware.
>
> If pci_dma_sync() doesn't perform the operation you want, please
> describe what that operation is.
>

Last time I checked pci_dma_sync was meant to sync the mapping when
ownership gets transferred from busmaster to cpu, i.e. after hardware
used/modified the buffer. What about the other direction when the cpu
filled a reused streaming map to device and wants to pass ownership to the
busmaster - we need to flush cpu caches to make sure the busmaster sees
the modified data.

<http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=103221032617171&amp;w=2>
<http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=103221300019951&amp;w=2>

Did I miss something?

Thanks,
Martin

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/