RE: [PATCH v2 08/10] PCI: layerscape: Add EP mode support for ls1088a and ls2088a
From: Xiaowei Bao
Date: Fri Aug 23 2019 - 20:18:28 EST
> -----Original Message-----
> From: Andrew Murray <andrew.murray@xxxxxxx>
> Sent: 2019年8月23日 22:28
> To: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> Cc: bhelgaas@xxxxxxxxxx; robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx;
> shawnguo@xxxxxxxxxx; Leo Li <leoyang.li@xxxxxxx>; kishon@xxxxxx;
> lorenzo.pieralisi@xxxxxx; arnd@xxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; 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
> Subject: Re: [PATCH v2 08/10] PCI: layerscape: Add EP mode support for
> ls1088a and ls2088a
>
> On Thu, Aug 22, 2019 at 07:22:40PM +0800, Xiaowei Bao wrote:
> > Add PCIe EP mode support for ls1088a and ls2088a, there are some
> > difference between LS1 and LS2 platform, so refactor the code of the
> > EP driver.
> >
> > Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> > ---
> > v2:
> > - New mechanism for layerscape EP driver.
>
> Was there a v1 of this patch?
Yes, but I don't know how to comments, ^_^
>
> >
> > drivers/pci/controller/dwc/pci-layerscape-ep.c | 76
> > ++++++++++++++++++++------
> > 1 file changed, 58 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > index 7ca5fe8..2a66f07 100644
> > --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> > @@ -20,27 +20,29 @@
> >
> > #define PCIE_DBI2_OFFSET 0x1000 /* DBI2 base address*/
> >
> > -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)
> > +
> > +struct ls_pcie_ep_drvdata {
> > + u32 func_offset;
> > + const struct dw_pcie_ep_ops *ops;
> > + const struct dw_pcie_ops *dw_pcie_ops;
> > };
> >
> > -#define to_ls_pcie_ep(x) dev_get_drvdata((x)->dev)
> > +struct ls_pcie_ep {
> > + struct dw_pcie *pci;
> > + struct pci_epc_features *ls_epc;
> > + const struct ls_pcie_ep_drvdata *drvdata; };
> >
> > static int ls_pcie_establish_link(struct dw_pcie *pci) {
> > return 0;
> > }
> >
> > -static const struct dw_pcie_ops ls_pcie_ep_ops = {
> > +static const struct dw_pcie_ops dw_ls_pcie_ep_ops = {
> > .start_link = ls_pcie_establish_link, };
> >
> > -static const struct of_device_id ls_pcie_ep_of_match[] = {
> > - { .compatible = "fsl,ls-pcie-ep",},
> > - { },
> > -};
> > -
> > static const struct pci_epc_features* ls_pcie_ep_get_features(struct
> > dw_pcie_ep *ep) { @@ -82,10 +84,44 @@ static int
> > ls_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> > }
> > }
> >
> > -static const struct dw_pcie_ep_ops pcie_ep_ops = {
> > +static unsigned int ls_pcie_ep_func_conf_select(struct dw_pcie_ep *ep,
> > + u8 func_no)
> > +{
> > + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > + struct ls_pcie_ep *pcie = to_ls_pcie_ep(pci);
> > + u8 header_type;
> > +
> > + header_type = ioread8(pci->dbi_base + PCI_HEADER_TYPE);
> > +
> > + if (header_type & (1 << 7))
> > + return pcie->drvdata->func_offset * func_no;
> > + else
> > + return 0;
>
> It looks like there isn't a PCI define for multi function, the nearest I could find
> was PCI_HEADER_TYPE_MULTIDEVICE in hotplug/ibmphp.h. A comment
> above the test might be helpful to explain the test.
Yes, I have not find the PCI_HEADER_TYPE_MULTIDEVICE define. OK, I will add
The comments in next version patch.
>
> As the ls_pcie_ep_drvdata structures are static, the unset .func_offset will be
> initialised to 0, so you could just drop the test above.
OK, thanks
>
> However something to the effect of the following may help spot
> misconfiguration:
>
> WARN_ON(func_no && !pcie->drvdata->func_offset); return
> pcie->drvdata->func_offset * func_no;
Thanks a lot, this looks better.
>
> The WARN is probably quite useful as if you are attempting to use non-zero
> functions and func_offset isn't set - then things may appear to work normally
> but actually will break horribly.
got it, thanks.
>
> Thanks,
>
> Andrew Murray
>
> > +}
> > +
> > +static const struct dw_pcie_ep_ops ls_pcie_ep_ops = {
> > .ep_init = ls_pcie_ep_init,
> > .raise_irq = ls_pcie_ep_raise_irq,
> > .get_features = ls_pcie_ep_get_features,
> > + .func_conf_select = ls_pcie_ep_func_conf_select, };
> > +
> > +static const struct ls_pcie_ep_drvdata ls1_ep_drvdata = {
> > + .ops = &ls_pcie_ep_ops,
> > + .dw_pcie_ops = &dw_ls_pcie_ep_ops,
> > +};
> > +
> > +static const struct ls_pcie_ep_drvdata ls2_ep_drvdata = {
> > + .func_offset = 0x20000,
> > + .ops = &ls_pcie_ep_ops,
> > + .dw_pcie_ops = &dw_ls_pcie_ep_ops,
> > +};
> > +
> > +static const struct of_device_id ls_pcie_ep_of_match[] = {
> > + { .compatible = "fsl,ls1046a-pcie-ep", .data = &ls1_ep_drvdata },
> > + { .compatible = "fsl,ls1088a-pcie-ep", .data = &ls2_ep_drvdata },
> > + { .compatible = "fsl,ls2088a-pcie-ep", .data = &ls2_ep_drvdata },
> > + { },
> > };
> >
> > static int __init ls_add_pcie_ep(struct ls_pcie_ep *pcie, @@ -98,7
> > +134,7 @@ static int __init ls_add_pcie_ep(struct ls_pcie_ep *pcie,
> > int ret;
> >
> > ep = &pci->ep;
> > - ep->ops = &pcie_ep_ops;
> > + ep->ops = pcie->drvdata->ops;
> >
> > res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> "addr_space");
> > if (!res)
> > @@ -137,14 +173,11 @@ static int __init ls_pcie_ep_probe(struct
> platform_device *pdev)
> > 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))
> > - return PTR_ERR(pci->dbi_base);
> > + pcie->drvdata = of_device_get_match_data(dev);
> >
> > - pci->dbi_base2 = pci->dbi_base + PCIE_DBI2_OFFSET;
> > pci->dev = dev;
> > - pci->ops = &ls_pcie_ep_ops;
> > + pci->ops = pcie->drvdata->dw_pcie_ops;
> > +
> > pcie->pci = pci;
> >
> > ls_epc->linkup_notifier = false,
> > @@ -152,6 +185,13 @@ static int __init ls_pcie_ep_probe(struct
> > platform_device *pdev)
> >
> > pcie->ls_epc = ls_epc;
> >
> > + 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))
> > + return PTR_ERR(pci->dbi_base);
> > +
> > + pci->dbi_base2 = pci->dbi_base + PCIE_DBI2_OFFSET;
> > +
> > platform_set_drvdata(pdev, pcie);
> >
> > ret = ls_add_pcie_ep(pcie, pdev);
> > --
> > 2.9.5
> >