Re: [PATCH 3/6] PCI: mobiveil: Add PCIe Gen4 EP driver for NXP Layerscape SoCs

From: Russell King - ARM Linux admin
Date: Tue Oct 15 2019 - 05:08:20 EST


On Tue, Oct 15, 2019 at 07:46:12AM +0000, Xiaowei Bao wrote:
>
>
> > -----Original Message-----
> > From: Russell King - ARM Linux admin <linux@xxxxxxxxxxxxxxx>
> > Sent: 2019å9æ25æ 0:39
> > To: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> > Cc: Z.q. Hou <zhiqiang.hou@xxxxxxx>; bhelgaas@xxxxxxxxxx;
> > robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; shawnguo@xxxxxxxxxx; Leo Li
> > <leoyang.li@xxxxxxx>; kishon@xxxxxx; lorenzo.pieralisi@xxxxxxx; M.h. Lian
> > <minghuan.lian@xxxxxxx>; andrew.murray@xxxxxxx; Mingkai Hu
> > <mingkai.hu@xxxxxxx>; linux-pci@xxxxxxxxxxxxxxx;
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Subject: Re: [PATCH 3/6] PCI: mobiveil: Add PCIe Gen4 EP driver for NXP
> > Layerscape SoCs
> >
> > On Mon, Sep 16, 2019 at 10:17:39AM +0800, Xiaowei Bao wrote:
> > > This PCIe controller is based on the Mobiveil GPEX IP, it work in EP
> > > mode if select this config opteration.
> > >
> > > Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> > > ---
> > > MAINTAINERS | 2 +
> > > drivers/pci/controller/mobiveil/Kconfig | 17 ++-
> > > drivers/pci/controller/mobiveil/Makefile | 1 +
> > > .../controller/mobiveil/pcie-layerscape-gen4-ep.c | 156
> > > +++++++++++++++++++++
> > > 4 files changed, 173 insertions(+), 3 deletions(-) create mode
> > > 100644 drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS index b997056..0858b54 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -12363,11 +12363,13 @@ F:
> > drivers/pci/controller/dwc/*layerscape*
> > >
> > > PCI DRIVER FOR NXP LAYERSCAPE GEN4 CONTROLLER
> > > M: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> > > +M: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> > > L: linux-pci@xxxxxxxxxxxxxxx
> > > L: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > > S: Maintained
> > > F: Documentation/devicetree/bindings/pci/layerscape-pcie-gen4.txt
> > > F: drivers/pci/controller/mobibeil/pcie-layerscape-gen4.c
> > > +F: drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> > >
> > > PCI DRIVER FOR GENERIC OF HOSTS
> > > M: Will Deacon <will@xxxxxxxxxx>
> > > diff --git a/drivers/pci/controller/mobiveil/Kconfig
> > > b/drivers/pci/controller/mobiveil/Kconfig
> > > index 2054950..0696b6e 100644
> > > --- a/drivers/pci/controller/mobiveil/Kconfig
> > > +++ b/drivers/pci/controller/mobiveil/Kconfig
> > > @@ -27,13 +27,24 @@ config PCIE_MOBIVEIL_PLAT
> > > for address translation and it is a PCIe Gen4 IP.
> > >
> > > config PCIE_LAYERSCAPE_GEN4
> > > - bool "Freescale Layerscape PCIe Gen4 controller"
> > > + bool "Freescale Layerscpe PCIe Gen4 controller in RC mode"
> > > depends on PCI
> > > depends on OF && (ARM64 || ARCH_LAYERSCAPE)
> > > depends on PCI_MSI_IRQ_DOMAIN
> > > select PCIE_MOBIVEIL_HOST
> > > help
> > > Say Y here if you want PCIe Gen4 controller support on
> > > - Layerscape SoCs. The PCIe controller can work in RC or
> > > - EP mode according to RCW[HOST_AGT_PEX] setting.
> > > + Layerscape SoCs. And the PCIe controller work in RC mode
> > > + by setting the RCW[HOST_AGT_PEX] to 0.
> > > +
> > > +config PCIE_LAYERSCAPE_GEN4_EP
> > > + bool "Freescale Layerscpe PCIe Gen4 controller in EP mode"
> > > + depends on PCI
> > > + depends on OF && (ARM64 || ARCH_LAYERSCAPE)
> > > + depends on PCI_ENDPOINT
> > > + select PCIE_MOBIVEIL_EP
> > > + help
> > > + Say Y here if you want PCIe Gen4 controller support on
> > > + Layerscape SoCs. And the PCIe controller work in EP mode
> > > + by setting the RCW[HOST_AGT_PEX] to 1.
> > > endmenu
> > > diff --git a/drivers/pci/controller/mobiveil/Makefile
> > > b/drivers/pci/controller/mobiveil/Makefile
> > > index 686d41f..6f54856 100644
> > > --- a/drivers/pci/controller/mobiveil/Makefile
> > > +++ b/drivers/pci/controller/mobiveil/Makefile
> > > @@ -4,3 +4,4 @@ obj-$(CONFIG_PCIE_MOBIVEIL_HOST) +=
> > > pcie-mobiveil-host.o
> > > obj-$(CONFIG_PCIE_MOBIVEIL_EP) += pcie-mobiveil-ep.o
> > > obj-$(CONFIG_PCIE_MOBIVEIL_PLAT) += pcie-mobiveil-plat.o
> > > obj-$(CONFIG_PCIE_LAYERSCAPE_GEN4) += pcie-layerscape-gen4.o
> > > +obj-$(CONFIG_PCIE_LAYERSCAPE_GEN4_EP) +=
> > pcie-layerscape-gen4-ep.o
> > > diff --git a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> > > b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> > > new file mode 100644
> > > index 0000000..7bfec51
> > > --- /dev/null
> > > +++ b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> > > @@ -0,0 +1,156 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * PCIe controller EP driver for Freescale Layerscape SoCs
> > > + *
> > > + * Copyright (C) 2019 NXP Semiconductor.
> > > + *
> > > + * Author: Xiaowei Bao <xiaowei.bao@xxxxxxx> */
> > > +
> > > +#include <linux/kernel.h>
> > > +#include <linux/init.h>
> > > +#include <linux/of_pci.h>
> > > +#include <linux/of_platform.h>
> > > +#include <linux/of_address.h>
> > > +#include <linux/pci.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/resource.h>
> > > +
> > > +#include "pcie-mobiveil.h"
> > > +
> > > +#define PCIE_LX2_BAR_NUM 4
> > > +
> > > +#define to_ls_pcie_g4_ep(x) dev_get_drvdata((x)->dev)
> > > +
> > > +struct ls_pcie_g4_ep {
> > > + struct mobiveil_pcie *mv_pci;
> > > +};
> > > +
> > > +static const struct of_device_id ls_pcie_g4_ep_of_match[] = {
> > > + { .compatible = "fsl,lx2160a-pcie-ep",},
> > > + { },
> > > +};
> > > +
> > > +static const struct pci_epc_features ls_pcie_g4_epc_features = {
> > > + .linkup_notifier = false,
> > > + .msi_capable = true,
> > > + .msix_capable = true,
> > > + .reserved_bar = (1 << BAR_4) | (1 << BAR_5),
> >
> > BIT(BAR_4) | BIT(BAR_5) ?
>
> I think use .reserved_bar = (1 << BAR_4) | (1 << BAR_5), is better, because BAR_4
> is not a bit of register.

Why is whether it's a register or not relevent?

--
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