[PATCH RFC] PCI: imx6: remove outbound io/mem ATU region mapping
pratyush.anand at st.com
Tue Nov 26 22:50:56 EST 2013
On Wed, Nov 27, 2013 at 04:46:09AM +0800, Marek Vasut wrote:
> 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.
Then if I do not miss anything, MX6 should work even without this patch.
> Best regards,
> Marek Vasut
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