Hi Jaehoon,
On Thu, 16 Apr 2015 15:59:45 -0700
Jaehoon Chung <jh80.chung@xxxxxxxxxxx> wrote:
> Hi,
>
> Well, I'm not sure..
> But in my understanding..configuration range might be support both "ranges" and "config" of reg.
>
> On 04/16/2015 10:59 PM, Jisheng Zhang wrote:
> > Hi all,
> >
> > I didn't fully understand the "ranges" usage, here is one situation which I dunno
> > how to handle.
> >
> > In arch/arm/boot/dts/berlin2q.dtsi, we describe the /soc ranges as
> >
> > ranges = <0 0xf7000000 0x1000000>;
> >
> > That's fine. Now there's a pci device based on pcie-designware.c which prefer
> > put "config" space in reg. But the config space starts at 0xe0000000, due to
> > the /soc ranges, the "config" space following pcie node is not correct in fact.
> >
> > soc {
> > ranges = <0 0xf7000000 0x1000000>;
> > ...
> > pcie: pcie@e40000 {
> > compatible = "...";
> > reg = <0xe40000 0x10000>, <0xe0000000 0x8000000>;
> > reg-names = "dbi", "pad", "config";
> > ...
> > };
> > ...
> > };
>
> According to yours,
>
> reg = <0xe40000 0x1000 /* dbi */
> 0xe000000 0x800000 /* pad */
> 0xf7000000 0x1000000>; /* config ? */
oops, there's no pad at all, dbi starts at 0xf7e40000, config space starts at 0xe0000000
so my pcie in my understanding is
pcie: pcie@e40000 {
compatible = "...";
reg = <0xe40000 0x10000>, <0xe0000000 0x8000000>;
reg-names = "dbi", "config";
};
But the "/soc" ranges is defined as "<0 0xf7000000 0x1000000>;", so the config space
in the above dts is not correct.
My solution is change the "/soc" ranges as following:
soc {
ranges;
...
};
Is there any elegant solutions for this situation?
>
> If there is not "config" into reg-names, it should be tried to find it into "ranges".
The pcie-designware driver prefers users define config space in "reg"
Thanks for your help,
Jisheng
>
> If my understanding is wrong, let me know, plz.
>
> In my case,
>
> reg = <0x156b0000 0x1000
> 0x15680000 0x1000
> 0x0c000000 0x1000>;
> reg-names = "elbi", "phy", "config";
>
> ranges = < ..... /* downstream I/O */
> ...... /* non-prefetchable memory */
>
>
> Best Regards,
> Jaehoon Chung
>
> >
> > How to define the "config" space in this situation? Did we need to change
> > the /soc ranges as the following?
> >
> > soc {
> > ranges;
> > }
> >
> > Thanks in advance,
> > Jisheng
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> >
>
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
