RE: [PATCH] PCI: layerscape: Add the SRIOV support in host side

[Xiaowei Bao <xiaowei.bao@nxp.com>]

> -----Original Message-----
> From: Marc Zyngier <maz@misterjones.org>
> Sent: 2019年12月2日 20:48
> To: Xiaowei Bao <xiaowei.bao@nxp.com>
> Cc: robh+dt@kernel.org; frowand.list@gmail.com; M.h. Lian
> <minghuan.lian@nxp.com>; Mingkai Hu <mingkai.hu@nxp.com>; Roy Zang
> <roy.zang@nxp.com>; lorenzo.pieralisi@arm.com; andrew.murray@arm.com;
> bhelgaas@google.com; devicetree@vger.kernel.org;
> linux-kernel@vger.kernel.org; linux-pci@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; Z.q. Hou <zhiqiang.hou@nxp.com>
> Subject: Re: [PATCH] PCI: layerscape: Add the SRIOV support in host side
> 
> On 2019-12-02 10:45, Xiaowei Bao wrote:
> > GIC get the map relations of devid and stream id from the msi-map
> > property of DTS, our platform add this property in u-boot base on the
> > PCIe device in the bus, but if enable the vf device in kernel, the vf
> > device msi-map will not set, so the vf device can't work, this patch
> > purpose is that manage the stream id and device id map relations
> > dynamically in kernel, and make the new PCIe device work in kernel.
> >
> > Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
> > ---
> >  drivers/of/irq.c                            |  9 +++
> >  drivers/pci/controller/dwc/pci-layerscape.c | 94
> > +++++++++++++++++++++++++++++
> >  drivers/pci/probe.c                         |  6 ++
> >  drivers/pci/remove.c                        |  6 ++
> >  4 files changed, 115 insertions(+)
> >
> > diff --git a/drivers/of/irq.c b/drivers/of/irq.c index
> > a296eaf..791e609 100644
> > --- a/drivers/of/irq.c
> > +++ b/drivers/of/irq.c
> > @@ -576,6 +576,11 @@ void __init of_irq_init(const struct of_device_id
> > *matches)
> >  	}
> >  }
> >
> > +u32 __weak ls_pcie_streamid_fix(struct device *dev, u32 rid) {
> > +	return rid;
> > +}
> > +
> >  static u32 __of_msi_map_rid(struct device *dev, struct device_node
> > **np,
> >  			    u32 rid_in)
> >  {
> > @@ -590,6 +595,10 @@ static u32 __of_msi_map_rid(struct device *dev,
> > struct device_node **np,
> >  		if (!of_map_rid(parent_dev->of_node, rid_in, "msi-map",
> >  				"msi-map-mask", np, &rid_out))
> >  			break;
> > +
> > +	if (rid_out == rid_in)
> > +		rid_out = ls_pcie_streamid_fix(parent_dev, rid_in);
> 
> Over my dead body. Get your firmware to properly program the LUT so that it
> presents the ITS with a reasonable topology. There is absolutely no way this
> kind of change makes it into the kernel.

Sorry for this, I know it is not reasonable, but I have no other way, as I know, ARM
get the mapping of stream ID to request ID from the msi-map property of DTS, if
add a new device which need the stream ID and try to get it from the msi-map of DTS,
it will failed and not work, yes? So could you give me a better advice to fix this issue,
I would really appreciate any comments or suggestions, thanks a lot.

Thanks 
Xiaowei

> 
> Thanks,
> 
>          M.
> --
> Who you jivin' with that Cosmik Debris?