RE: [PATCH 05/10] PCI: layerscape: Modify the way of getting capability with different PEX

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

> -----Original Message-----
> From: Andrew Murray <andrew.murray@arm.com>
> Sent: 2019年8月16日 18:26
> To: Xiaowei Bao <xiaowei.bao@nxp.com>
> Cc: jingoohan1@gmail.com; gustavo.pimentel@synopsys.com;
> bhelgaas@google.com; robh+dt@kernel.org; mark.rutland@arm.com;
> shawnguo@kernel.org; Leo Li <leoyang.li@nxp.com>; kishon@ti.com;
> lorenzo.pieralisi@arm.com; arnd@arndb.de; gregkh@linuxfoundation.org;
> M.h. Lian <minghuan.lian@nxp.com>; Mingkai Hu <mingkai.hu@nxp.com>;
> Roy Zang <roy.zang@nxp.com>; linux-pci@vger.kernel.org;
> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linuxppc-dev@lists.ozlabs.org; Z.q. Hou
> <zhiqiang.hou@nxp.com>
> Subject: Re: [PATCH 05/10] PCI: layerscape: Modify the way of getting
> capability with different PEX
> 
> On Fri, Aug 16, 2019 at 03:00:00AM +0000, Xiaowei Bao wrote:
> >
> >
> > > -----Original Message-----
> > > From: Andrew Murray <andrew.murray@arm.com>
> > > Sent: 2019年8月15日 20:51
> > > To: Xiaowei Bao <xiaowei.bao@nxp.com>
> > > Cc: jingoohan1@gmail.com; gustavo.pimentel@synopsys.com;
> > > bhelgaas@google.com; robh+dt@kernel.org; mark.rutland@arm.com;
> > > shawnguo@kernel.org; Leo Li <leoyang.li@nxp.com>; kishon@ti.com;
> > > lorenzo.pieralisi@arm.com; arnd@arndb.de;
> > > gregkh@linuxfoundation.org; M.h. Lian <minghuan.lian@nxp.com>;
> > > Mingkai Hu <mingkai.hu@nxp.com>; Roy Zang <roy.zang@nxp.com>;
> > > linux-pci@vger.kernel.org; devicetree@vger.kernel.org;
> > > linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> > > linuxppc-dev@lists.ozlabs.org
> > > Subject: Re: [PATCH 05/10] PCI: layerscape: Modify the way of
> > > getting capability with different PEX
> > >
> > > On Thu, Aug 15, 2019 at 04:37:11PM +0800, Xiaowei Bao wrote:
> > > > The different PCIe controller in one board may be have different
> > > > capability of MSI or MSIX, so change the way of getting the MSI
> > > > capability, make it more flexible.
> > > >
> > > > Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
> > > > ---
> > > >  drivers/pci/controller/dwc/pci-layerscape-ep.c | 28
> > > > +++++++++++++++++++-------
> > > >  1 file changed, 21 insertions(+), 7 deletions(-)
> > > >
> > > > diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > index be61d96..9404ca0 100644
> > > > --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > > > @@ -22,6 +22,7 @@
> > > >
> > > >  struct ls_pcie_ep {
> > > >  	struct dw_pcie		*pci;
> > > > +	struct pci_epc_features	*ls_epc;
> > > >  };
> > > >
> > > >  #define to_ls_pcie_ep(x)	dev_get_drvdata((x)->dev)
> > > > @@ -40,25 +41,26 @@ static const struct of_device_id
> > > ls_pcie_ep_of_match[] = {
> > > >  	{ },
> > > >  };
> > > >
> > > > -static const struct pci_epc_features ls_pcie_epc_features = {
> > > > -	.linkup_notifier = false,
> > > > -	.msi_capable = true,
> > > > -	.msix_capable = false,
> > > > -};
> > > > -
> > > >  static const struct pci_epc_features*
> > > > ls_pcie_ep_get_features(struct dw_pcie_ep *ep)  {
> > > > -	return &ls_pcie_epc_features;
> > > > +	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > > +	struct ls_pcie_ep *pcie = to_ls_pcie_ep(pci);
> > > > +
> > > > +	return pcie->ls_epc;
> > > >  }
> > > >
> > > >  static void ls_pcie_ep_init(struct dw_pcie_ep *ep)  {
> > > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > > +	struct ls_pcie_ep *pcie = to_ls_pcie_ep(pci);
> > > >  	enum pci_barno bar;
> > > >
> > > >  	for (bar = BAR_0; bar <= BAR_5; bar++)
> > > >  		dw_pcie_ep_reset_bar(pci, bar);
> > > > +
> > > > +	pcie->ls_epc->msi_capable = ep->msi_cap ? true : false;
> > > > +	pcie->ls_epc->msix_capable = ep->msix_cap ? true : false;
> > > >  }
> > > >
> > > >  static int ls_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8
> > > > func_no, @@
> > > > -118,6 +120,7 @@ static int __init ls_pcie_ep_probe(struct
> > > > platform_device
> > > *pdev)
> > > >  	struct device *dev = &pdev->dev;
> > > >  	struct dw_pcie *pci;
> > > >  	struct ls_pcie_ep *pcie;
> > > > +	struct pci_epc_features *ls_epc;
> > > >  	struct resource *dbi_base;
> > > >  	int ret;
> > > >
> > > > @@ -129,6 +132,10 @@ static int __init ls_pcie_ep_probe(struct
> > > platform_device *pdev)
> > > >  	if (!pci)
> > > >  		return -ENOMEM;
> > > >
> > > > +	ls_epc = devm_kzalloc(dev, sizeof(*ls_epc), GFP_KERNEL);
> > > > +	if (!ls_epc)
> > > > +		return -ENOMEM;
> > > > +
> > > >  	dbi_base = platform_get_resource_byname(pdev,
> IORESOURCE_MEM,
> > > "regs");
> > > >  	pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
> > > >  	if (IS_ERR(pci->dbi_base))
> > > > @@ -139,6 +146,13 @@ static int __init ls_pcie_ep_probe(struct
> > > platform_device *pdev)
> > > >  	pci->ops = &ls_pcie_ep_ops;
> > > >  	pcie->pci = pci;
> > > >
> > > > +	ls_epc->linkup_notifier = false,
> > > > +	ls_epc->msi_capable = true,
> > > > +	ls_epc->msix_capable = true,
> > >
> > > As [msi,msix]_capable is shortly set from ls_pcie_ep_init - is there
> > > any reason to set them here (to potentially incorrect values)?
> > This is a INIT value, maybe false is better for msi_capable and
> > msix_capable, of course, we don't need to set it.
> 
> ls_epc is kzalloc'd and so all zeros, so you get false for free. I think you can
> remove these two lines (or all three if you don't care that linkup_notifier isn't
> explicitly set).
Agree, This is correct, thanks a lot.
> 
> Thanks,
> 
> Andrew Murray
> 
> > >
> > > Thanks,
> > >
> > > Andrew Murray
> > >
> > > > +	ls_epc->bar_fixed_64bit = (1 << BAR_2) | (1 << BAR_4),
> > > > +
> > > > +	pcie->ls_epc = ls_epc;
> > > > +
> > > >  	platform_set_drvdata(pdev, pcie);
> > > >
> > > >  	ret = ls_add_pcie_ep(pcie, pdev);
> > > > --
> > > > 2.9.5
> > > >