RE: [PATCHv4 1/3] ARMv8: dts: ls1046a: add the property of IB and OB

[M.h. Lian]

> -----Original Message-----
> From: Leo Li
> Sent: Saturday, November 11, 2017 5:21 AM
> To: Kishon Vijay Abraham I <kishon@xxxxxx>; Xiaowei Bao
> <xiaowei.bao@xxxxxxx>; robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx;
> catalin.marinas@xxxxxxx; will.deacon@xxxxxxx; bhelgaas@xxxxxxxxxx;
> shawnguo@xxxxxxxxxx; Madalin-cristian Bucur <madalin.bucur@xxxxxxx>;
> Sumit Garg <sumit.garg@xxxxxxx>; Y.b. Lu <yangbo.lu@xxxxxxx>; Andy Tang
> <andy.tang@xxxxxxx>; jingoohan1@xxxxxxxxx; pbrobinson@xxxxxxxxx;
> songxiaowei@xxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxx; linuxppc-dev@xxxxxxxxxxxxxxxx; Z.q. Hou
> <zhiqiang.hou@xxxxxxx>; Mingkai Hu <mingkai.hu@xxxxxxx>; M.h. Lian
> <minghuan.lian@xxxxxxx>
> Subject: RE: [PATCHv4 1/3] ARMv8: dts: ls1046a: add the property of IB and OB
> 
> 
> 
> > -----Original Message-----
> > From: Kishon Vijay Abraham I [mailto:kishon@xxxxxx]
> > Sent: Friday, November 10, 2017 12:22 AM
> > To: Xiaowei Bao <xiaowei.bao@xxxxxxx>; robh+dt@xxxxxxxxxx;
> > mark.rutland@xxxxxxx; catalin.marinas@xxxxxxx; will.deacon@xxxxxxx;
> > bhelgaas@xxxxxxxxxx; shawnguo@xxxxxxxxxx; Madalin-cristian Bucur
> > <madalin.bucur@xxxxxxx>; Sumit Garg <sumit.garg@xxxxxxx>; Y.b. Lu
> > <yangbo.lu@xxxxxxx>; hongtao.jia@xxxxxxx; Andy Tang
> > <andy.tang@xxxxxxx>; Leo Li <leoyang.li@xxxxxxx>;
> > jingoohan1@xxxxxxxxx; pbrobinson@xxxxxxxxx; songxiaowei@xxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> > linux- kernel@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linuxppc-
> > dev@xxxxxxxxxxxxxxxx; Z.q. Hou <zhiqiang.hou@xxxxxxx>; Mingkai Hu
> > <mingkai.hu@xxxxxxx>; M.h. Lian <minghuan.lian@xxxxxxx>
> > Subject: Re: [PATCHv4 1/3] ARMv8: dts: ls1046a: add the property of IB
> > and OB
> >
> > Hi Bao,
> >
> > On Friday 10 November 2017 09:18 AM, Bao Xiaowei wrote:
> > > Add the property of inbound and outbound windows number for ep driver.
> > >
> > > Signed-off-by: Bao Xiaowei <xiaowei.bao@xxxxxxx>
> > > Acked-by: Minghuan Lian <minghuan.Lian@xxxxxxx>
> > > ---
> > >  v2:
> > >  - no change
> > >  v3:
> > >  - modify the commit message
> > >  v4:
> > >  - no change
> > >
> > >  arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi | 6 ++++++
> > >  1 file changed, 6 insertions(+)
> >
> > $subject should start with something like
> > arm64: dts: ls1046a: **
> > >
> > > diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi
> > > b/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi
> > > index 06b5e12d04d8..f8332669663c 100644
> > > --- a/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi
> > > +++ b/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi
> > > @@ -674,6 +674,8 @@
> > >  			device_type = "pci";
> > >  			dma-coherent;
> > >  			num-lanes = <4>;
> > > +			num-ib-windows = <6>;
> > > +			num-ob-windows = <6>;
> >
> > EP specific properties shouldn't be added in RC dt node. Ideally you
> > should have a separate dt node for RC and EP.
> 
> It is a single PCIe controller which can be configured to either RC mode or EP
> mode.  Wouldn't it conflict with the device tree principles to have two device
> tree nodes for the same PCIe controller?  And obviously the two modes cannot
> be used at the same time so we cannot have two drivers both probe on the
> same hardware.
> 
[Minghuan Lian]  There is only one PCIe dts node in the dts file. PCIe dts node describes the PCIe controller's hardware properties and does not have work mode.  The new properties  "num-ib-windows " and "num-ob-windows" are used to describe the inbound/outbound window number included in the PCIe hardware. These windows are used in both RC and EP mode.  We can change work mode when resetting via RCW(reset configuration word).


> Regards,
> Leo