RE: [PATCH v3 08/11] PCI: layerscape: Modify the MSIX to the doorbell mode

From: Gustavo Pimentel
Date: Mon Sep 16 2019 - 04:54:17 EST


On Sat, Sep 14, 2019 at 7:37:54, Xiaowei Bao <xiaowei.bao@xxxxxxx> wrote:

>
>
> > -----Original Message-----
> > From: Gustavo Pimentel <Gustavo.Pimentel@xxxxxxxxxxxx>
> > Sent: 2019å9æ12æ 19:24
> > To: Andrew Murray <andrew.murray@xxxxxxx>; Xiaowei Bao
> > <xiaowei.bao@xxxxxxx>
> > Cc: robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; shawnguo@xxxxxxxxxx; Leo
> > Li <leoyang.li@xxxxxxx>; kishon@xxxxxx; lorenzo.pieralisi@xxxxxxx; M.h.
> > Lian <minghuan.lian@xxxxxxx>; Mingkai Hu <mingkai.hu@xxxxxxx>; Roy
> > Zang <roy.zang@xxxxxxx>; jingoohan1@xxxxxxxxx;
> > gustavo.pimentel@xxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linuxppc-dev@xxxxxxxxxxxxxxxx;
> > arnd@xxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; Z.q. Hou
> > <zhiqiang.hou@xxxxxxx>
> > Subject: RE: [PATCH v3 08/11] PCI: layerscape: Modify the MSIX to the
> > doorbell mode
> >
> > Hi,
> >
> > Sorry for the delay I was in parental leave and I'm still trying not to drown in
> > the mailing list emails... ð
> >
> > On Mon, Sep 2, 2019 at 13:1:47, Andrew Murray <andrew.murray@xxxxxxx>
> > wrote:
> >
> > > On Mon, Sep 02, 2019 at 11:17:13AM +0800, Xiaowei Bao wrote:
> > > > dw_pcie_ep_raise_msix_irq was never called in the exisitng driver
> > > > before, because the ls1046a platform don't support the MSIX feature
> > > > and msix_capable was always set to false.
> > > > Now that add the ls1088a platform with MSIX support, but the
> > > > existing dw_pcie_ep_raise_msix_irq doesn't work, so use the doorbell
> > > > method to support the MSIX feature.
> >
> > Hum... the implementation of msix implementation did work on my use case,
> > however, at the time the setup used for developing and testing the
> > implementation only had one PF (by default 0). Perhaps this could was is
> > causing the different behavior between our setups.
> >
> > You have more than one PF, right?
>
> Yes, I have two PFs.

Probably that's the reason why my MSI-X raise function implementation
didn't work on your case.

>
> Thanks
> Xiaowei
>
> >
> > If I remember correctly, msix feature support entered on kernel 4.19 version
> > and it worked quite well at the time, but I didn't test since there (I've to
> > manage time to be able to retest it again), I'm didn't seen any patch that
> > could interfere with this.
> >
> > Regards,
> > Gustavo
> >
> >
> > > >
> > > > Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> > >
> > > Reviewed-by: Andrew Murray <andrew.murray@xxxxxxx>
> > >
> > > > ---
> > > > v2:
> > > > - No change
> > > > v3:
> > > > - Modify the commit message make it clearly.
> > > >
> > > > drivers/pci/controller/dwc/pci-layerscape-ep.c | 3 ++-
> > > > 1 file changed, 2 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > index 1e07287..5f0cb99 100644
> > > > --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > @@ -79,7 +79,8 @@ static int ls_pcie_ep_raise_irq(struct dw_pcie_ep
> > *ep, u8 func_no,
> > > > case PCI_EPC_IRQ_MSI:
> > > > return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
> > > > case PCI_EPC_IRQ_MSIX:
> > > > - return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
> > > > + return dw_pcie_ep_raise_msix_irq_doorbell(ep, func_no,
> > > > + interrupt_num);
> > > > default:
> > > > dev_err(pci->dev, "UNKNOWN IRQ type\n");
> > > > return -EINVAL;
> > > > --
> > > > 2.9.5
> > > >
> >