[PATCH RFC] PCI: imx6: remove outbound io/mem ATU region mapping

Marek Vasut marex at denx.de
Tue Nov 26 15:46:09 EST 2013

Dear Pratyush Anand,

> Hi,
> On Wed, Oct 23, 2013 at 12:55:43PM +0800, Tim Harvey wrote:
> > The IMX6 iATU is used for address translation between the AXI bus
> > address space and PCI address space.  This is used for type0 and type1
> > config cycles but is not necessary for outbound io/mem regions.
> > 
> > This patch removes the calls that inappropriately re-configures the ATU
> > viewport for outbound memory and IO after config cycles and removes them
> > altogether as they are not necessary.
> > 
> > This resolves issues with PCI devices behind switches and has been tested
> > with a Gige device behind a PLX PEX860x switch.  More testing is needed
> > for other configurations.
> It seems to me that in your controller you have only one view port.
> Also mem_base and mem_bus_addr is same. Thats why it works in your
> case.

MX6 has 4 In/4 Out viewports AFAICT.

Best regards,
Marek Vasut

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