Re: [PATCH v8 1/4] pci:host: APM X-Gene PCIe host controller driver

From: Liviu Dudau <Liviu.Dudau@arm.com>
To: Tanmay Inamdar <tinamdar@apm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Jason Gunthorpe <jgunthorpe@obsidianresearch.com>,
	"grant.likely@linaro.org" <grant.likely@linaro.org>,
	Rob Herring <robh+dt@kernel.org>,
	Catalin Marinas <Catalin.Marinas@arm.com>,
	Rob Landley <rob@landley.net>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"patches@apm.com" <patches@apm.com>,
	"jcm@redhat.com" <jcm@redhat.com>
Subject: Re: [PATCH v8 1/4] pci:host: APM X-Gene PCIe host controller driver
Date: Fri, 12 Sep 2014 10:18:16 +0100	[thread overview]
Message-ID: <20140912091816.GU27864@e106497-lin.cambridge.arm.com> (raw)
In-Reply-To: <1410476266-29426-2-git-send-email-tinamdar@apm.com>

On Thu, Sep 11, 2014 at 11:57:43PM +0100, Tanmay Inamdar wrote:
> This patch adds the AppliedMicro X-Gene SOC PCIe host controller driver.
> X-Gene PCIe controller supports maximum up to 8 lanes and GEN3 speed.
> X-Gene SOC supports maximum 5 PCIe ports.
> 
> Signed-off-by: Tanmay Inamdar <tinamdar@apm.com>

Hi Tanmay,

It looks good to me now. You can add if you care:

Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com>

Best regards,
Liviu

> ---
>  drivers/pci/host/Kconfig     |  10 +
>  drivers/pci/host/Makefile    |   1 +
>  drivers/pci/host/pci-xgene.c | 646 +++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 657 insertions(+)
>  create mode 100644 drivers/pci/host/pci-xgene.c
> 
> diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
> index 90f5cca..382fd3d 100644
> --- a/drivers/pci/host/Kconfig
> +++ b/drivers/pci/host/Kconfig
> @@ -63,4 +63,14 @@ config PCIE_SPEAR13XX
>         help
>           Say Y here if you want PCIe support on SPEAr13XX SoCs.
> 
> +config PCI_XGENE
> +       bool "X-Gene PCIe controller"
> +       depends on ARCH_XGENE
> +       depends on OF
> +       select PCIEPORTBUS
> +       help
> +         Say Y here if you want internal PCI support on APM X-Gene SoC.
> +         There are 5 internal PCIe ports available. Each port is GEN3 capable
> +         and have varied lanes from x1 to x8.
> +
>  endmenu
> diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
> index d0e88f1..845611f 100644
> --- a/drivers/pci/host/Makefile
> +++ b/drivers/pci/host/Makefile
> @@ -8,3 +8,4 @@ obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
>  obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o
>  obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
>  obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
> +obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
> diff --git a/drivers/pci/host/pci-xgene.c b/drivers/pci/host/pci-xgene.c
> new file mode 100644
> index 0000000..dae61a6
> --- /dev/null
> +++ b/drivers/pci/host/pci-xgene.c
> @@ -0,0 +1,646 @@
> +/**
> + * APM X-Gene PCIe Driver
> + *
> + * Copyright (c) 2014 Applied Micro Circuits Corporation.
> + *
> + * Author: Tanmay Inamdar <tinamdar@apm.com>.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + */
> +#include <linux/clk-private.h>
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/jiffies.h>
> +#include <linux/memblock.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_pci.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#define PCIECORE_CTLANDSTATUS          0x50
> +#define PIM1_1L                                0x80
> +#define IBAR2                          0x98
> +#define IR2MSK                         0x9c
> +#define PIM2_1L                                0xa0
> +#define IBAR3L                         0xb4
> +#define IR3MSKL                                0xbc
> +#define PIM3_1L                                0xc4
> +#define OMR1BARL                       0x100
> +#define OMR2BARL                       0x118
> +#define OMR3BARL                       0x130
> +#define CFGBARL                                0x154
> +#define CFGBARH                                0x158
> +#define CFGCTL                         0x15c
> +#define RTDID                          0x160
> +#define BRIDGE_CFG_4                   0x2010
> +#define BRIDGE_STATUS_0                        0x2600
> +
> +#define LINK_UP_MASK                   0x00000100
> +#define AXI_EP_CFG_ACCESS              0x10000
> +#define EN_COHERENCY                   0xF0000000
> +#define EN_REG                         0x00000001
> +#define OB_LO_IO                       0x00000002
> +#define XGENE_PCIE_VENDORID            0x10E8
> +#define XGENE_PCIE_DEVICEID            0xE004
> +#define SZ_1T                          (SZ_1G*1024ULL)
> +#define PIPE_PHY_RATE_RD(src)          ((0xc000 & (u32)(src)) >> 0xe)
> +
> +struct xgene_pcie_port {
> +       struct device_node      *node;
> +       struct device           *dev;
> +       struct clk              *clk;
> +       void __iomem            *csr_base;
> +       void __iomem            *cfg_base;
> +       unsigned long           cfg_addr;
> +       bool                    link_up;
> +};
> +
> +static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
> +{
> +       return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags;
> +}
> +
> +/* PCIE Configuration Out/In */
> +static inline void xgene_pcie_cfg_out32(void __iomem *addr, int offset, u32 val)
> +{
> +       writel(val, addr + offset);
> +}
> +
> +static inline void xgene_pcie_cfg_out16(void __iomem *addr, int offset, u16 val)
> +{
> +       u32 val32 = readl(addr + (offset & ~0x3));
> +
> +       switch (offset & 0x3) {
> +       case 2:
> +               val32 &= ~0xFFFF0000;
> +               val32 |= (u32)val << 16;
> +               break;
> +       case 0:
> +       default:
> +               val32 &= ~0xFFFF;
> +               val32 |= val;
> +               break;
> +       }
> +       writel(val32, addr + (offset & ~0x3));
> +}
> +
> +static inline void xgene_pcie_cfg_out8(void __iomem *addr, int offset, u8 val)
> +{
> +       u32 val32 = readl(addr + (offset & ~0x3));
> +
> +       switch (offset & 0x3) {
> +       case 0:
> +               val32 &= ~0xFF;
> +               val32 |= val;
> +               break;
> +       case 1:
> +               val32 &= ~0xFF00;
> +               val32 |= (u32)val << 8;
> +               break;
> +       case 2:
> +               val32 &= ~0xFF0000;
> +               val32 |= (u32)val << 16;
> +               break;
> +       case 3:
> +       default:
> +               val32 &= ~0xFF000000;
> +               val32 |= (u32)val << 24;
> +               break;
> +       }
> +       writel(val32, addr + (offset & ~0x3));
> +}
> +
> +static inline void xgene_pcie_cfg_in32(void __iomem *addr, int offset, u32 *val)
> +{
> +       *val = readl(addr + offset);
> +}
> +
> +static inline void
> +xgene_pcie_cfg_in16(void __iomem *addr, int offset, u32 *val)
> +{
> +       *val = readl(addr + (offset & ~0x3));
> +
> +       switch (offset & 0x3) {
> +       case 2:
> +               *val >>= 16;
> +               break;
> +       }
> +
> +       *val &= 0xFFFF;
> +}
> +
> +static inline void
> +xgene_pcie_cfg_in8(void __iomem *addr, int offset, u32 *val)
> +{
> +       *val = readl(addr + (offset & ~0x3));
> +
> +       switch (offset & 0x3) {
> +       case 3:
> +               *val = *val >> 24;
> +               break;
> +       case 2:
> +               *val = *val >> 16;
> +               break;
> +       case 1:
> +               *val = *val >> 8;
> +               break;
> +       }
> +       *val &= 0xFF;
> +}
> +
> +/* When the address bit [17:16] is 2'b01, the Configuration access will be
> + * treated as Type 1 and it will be forwarded to external PCIe device.
> + */
> +static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
> +{
> +       struct xgene_pcie_port *port = bus->sysdata;
> +
> +       if (bus->number >= (bus->primary + 1))
> +               return port->cfg_base + AXI_EP_CFG_ACCESS;
> +
> +       return port->cfg_base;
> +}
> +
> +/* For Configuration request, RTDID register is used as Bus Number,
> + * Device Number and Function number of the header fields.
> + */
> +static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
> +{
> +       struct xgene_pcie_port *port = bus->sysdata;
> +       unsigned int b, d, f;
> +       u32 rtdid_val = 0;
> +
> +       b = bus->number;
> +       d = PCI_SLOT(devfn);
> +       f = PCI_FUNC(devfn);
> +
> +       if (!pci_is_root_bus(bus))
> +               rtdid_val = (b << 8) | (d << 3) | f;
> +
> +       writel(rtdid_val, port->csr_base + RTDID);
> +       /* read the register back to ensure flush */
> +       readl(port->csr_base + RTDID);
> +}
> +
> +static int xgene_pcie_read_config(struct pci_bus *bus, unsigned int devfn,
> +                                 int offset, int len, u32 *val)
> +{
> +       struct xgene_pcie_port *port = bus->sysdata;
> +       void __iomem *addr;
> +
> +       if ((pci_is_root_bus(bus) && devfn != 0) || !port->link_up)
> +               return PCIBIOS_DEVICE_NOT_FOUND;
> +
> +       xgene_pcie_set_rtdid_reg(bus, devfn);
> +       addr = xgene_pcie_get_cfg_base(bus);
> +       switch (len) {
> +       case 1:
> +               xgene_pcie_cfg_in8(addr, offset, val);
> +               break;
> +       case 2:
> +               xgene_pcie_cfg_in16(addr, offset, val);
> +               break;
> +       default:
> +               xgene_pcie_cfg_in32(addr, offset, val);
> +               break;
> +       }
> +       return PCIBIOS_SUCCESSFUL;
> +}
> +
> +static int xgene_pcie_write_config(struct pci_bus *bus, unsigned int devfn,
> +                                  int offset, int len, u32 val)
> +{
> +       struct xgene_pcie_port *port = bus->sysdata;
> +       void __iomem *addr;
> +
> +       if ((pci_is_root_bus(bus) && devfn != 0) || !port->link_up)
> +               return PCIBIOS_DEVICE_NOT_FOUND;
> +
> +       xgene_pcie_set_rtdid_reg(bus, devfn);
> +       addr = xgene_pcie_get_cfg_base(bus);
> +       switch (len) {
> +       case 1:
> +               xgene_pcie_cfg_out8(addr, offset, (u8)val);
> +               break;
> +       case 2:
> +               xgene_pcie_cfg_out16(addr, offset, (u16)val);
> +               break;
> +       default:
> +               xgene_pcie_cfg_out32(addr, offset, val);
> +               break;
> +       }
> +
> +       return PCIBIOS_SUCCESSFUL;
> +}
> +
> +static struct pci_ops xgene_pcie_ops = {
> +       .read = xgene_pcie_read_config,
> +       .write = xgene_pcie_write_config
> +};
> +
> +static u64 xgene_pcie_set_ib_mask(void __iomem *csr_base, u32 addr,
> +                                 u32 flags, u64 size)
> +{
> +       u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags;
> +       u32 val32 = 0;
> +       u32 val;
> +
> +       val32 = readl(csr_base + addr);
> +       val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16);
> +       writel(val, csr_base + addr);
> +
> +       val32 = readl(csr_base + addr + 0x04);
> +       val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16);
> +       writel(val, csr_base + addr + 0x04);
> +
> +       val32 = readl(csr_base + addr + 0x04);
> +       val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16);
> +       writel(val, csr_base + addr + 0x04);
> +
> +       val32 = readl(csr_base + addr + 0x08);
> +       val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16);
> +       writel(val, csr_base + addr + 0x08);
> +
> +       return mask;
> +}
> +
> +static void xgene_pcie_linkup(struct xgene_pcie_port *port,
> +                                  u32 *lanes, u32 *speed)
> +{
> +       void __iomem *csr_base = port->csr_base;
> +       u32 val32;
> +
> +       port->link_up = false;
> +       val32 = readl(csr_base + PCIECORE_CTLANDSTATUS);
> +       if (val32 & LINK_UP_MASK) {
> +               port->link_up = true;
> +               *speed = PIPE_PHY_RATE_RD(val32);
> +               val32 = readl(csr_base + BRIDGE_STATUS_0);
> +               *lanes = val32 >> 26;
> +       }
> +}
> +
> +static int xgene_pcie_init_port(struct xgene_pcie_port *port)
> +{
> +       int rc;
> +
> +       port->clk = clk_get(port->dev, NULL);
> +       if (IS_ERR(port->clk)) {
> +               dev_err(port->dev, "clock not available\n");
> +               return -ENODEV;
> +       }
> +
> +       rc = clk_prepare_enable(port->clk);
> +       if (rc) {
> +               dev_err(port->dev, "clock enable failed\n");
> +               return rc;
> +       }
> +
> +       return 0;
> +}
> +
> +static void xgene_pcie_fixup_bridge(struct pci_dev *dev)
> +{
> +       int i;
> +
> +       /* Hide the PCI host BARs from the kernel as their content doesn't
> +        * fit well in the resource management
> +        */
> +       for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
> +               dev->resource[i].start = dev->resource[i].end = 0;
> +               dev->resource[i].flags = 0;
> +       }
> +       dev_info(&dev->dev, "Hiding X-Gene pci host bridge resources %s\n",
> +                pci_name(dev));
> +}
> +DECLARE_PCI_FIXUP_HEADER(XGENE_PCIE_VENDORID, XGENE_PCIE_DEVICEID,
> +                        xgene_pcie_fixup_bridge);
> +
> +static int xgene_pcie_map_reg(struct xgene_pcie_port *port,
> +                             struct platform_device *pdev)
> +{
> +       struct resource *res;
> +
> +       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr");
> +       port->csr_base = devm_ioremap_resource(port->dev, res);
> +       if (IS_ERR(port->csr_base))
> +               return PTR_ERR(port->csr_base);
> +
> +       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> +       port->cfg_base = devm_ioremap_resource(port->dev, res);
> +       if (IS_ERR(port->cfg_base))
> +               return PTR_ERR(port->cfg_base);
> +       port->cfg_addr = res->start;
> +
> +       return 0;
> +}
> +
> +static void xgene_pcie_setup_ob_reg(struct xgene_pcie_port *port,
> +                                   struct resource *res, u32 offset,
> +                                   u64 cpu_addr, u64 pci_addr)
> +{
> +       void __iomem *base = port->csr_base + offset;
> +       resource_size_t size = resource_size(res);
> +       u64 restype = resource_type(res);
> +       u64 mask = 0;
> +       u32 min_size;
> +       u32 flag = EN_REG;
> +
> +       if (restype == IORESOURCE_MEM) {
> +               min_size = SZ_128M;
> +       } else {
> +               min_size = 128;
> +               flag |= OB_LO_IO;
> +       }
> +
> +       if (size >= min_size)
> +               mask = ~(size - 1) | flag;
> +       else
> +               dev_warn(port->dev, "res size 0x%llx less than minimum 0x%x\n",
> +                        (u64)size, min_size);
> +
> +       writel(lower_32_bits(cpu_addr), base);
> +       writel(upper_32_bits(cpu_addr), base + 0x04);
> +       writel(lower_32_bits(mask), base + 0x08);
> +       writel(upper_32_bits(mask), base + 0x0c);
> +       writel(lower_32_bits(pci_addr), base + 0x10);
> +       writel(upper_32_bits(pci_addr), base + 0x14);
> +}
> +
> +static void xgene_pcie_setup_cfg_reg(void __iomem *csr_base, u64 addr)
> +{
> +       writel(lower_32_bits(addr), csr_base + CFGBARL);
> +       writel(upper_32_bits(addr), csr_base + CFGBARH);
> +       writel(EN_REG, csr_base + CFGCTL);
> +}
> +
> +static int xgene_pcie_map_ranges(struct xgene_pcie_port *port,
> +                                struct list_head *res,
> +                                resource_size_t io_base)
> +{
> +       struct pci_host_bridge_window *window;
> +       struct device *dev = port->dev;
> +       int ret;
> +
> +       list_for_each_entry(window, res, list) {
> +               struct resource *res = window->res;
> +               u64 restype = resource_type(res);
> +
> +               dev_dbg(port->dev, "0x%08lx 0x%016llx...0x%016llx\n",
> +                       res->flags, res->start, res->end);
> +
> +               switch (restype) {
> +               case IORESOURCE_IO:
> +                       xgene_pcie_setup_ob_reg(port, res, OMR3BARL, io_base,
> +                                               res->start - window->offset);
> +                       ret = pci_remap_iospace(res, io_base);
> +                       if (ret < 0)
> +                               return ret;
> +                       break;
> +               case IORESOURCE_MEM:
> +                       xgene_pcie_setup_ob_reg(port, res, OMR1BARL, res->start,
> +                                               res->start - window->offset);
> +                       break;
> +               case IORESOURCE_BUS:
> +                       break;
> +               default:
> +                       dev_err(dev, "invalid io resource!");
> +                       return -EINVAL;
> +               }
> +       }
> +       xgene_pcie_setup_cfg_reg(port->csr_base, port->cfg_addr);
> +
> +       return 0;
> +}
> +
> +static void xgene_pcie_setup_pims(void *addr, u64 pim, u64 size)
> +{
> +       writel(lower_32_bits(pim), addr);
> +       writel(upper_32_bits(pim) | EN_COHERENCY, addr + 0x04);
> +       writel(lower_32_bits(size), addr + 0x10);
> +       writel(upper_32_bits(size), addr + 0x14);
> +}
> +
> +/*
> + * X-Gene PCIe support maximum 3 inbound memory regions
> + * This function helps to select a region based on size of region
> + */
> +static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
> +{
> +       if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) {
> +               *ib_reg_mask |= (1 << 1);
> +               return 1;
> +       }
> +
> +       if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
> +               *ib_reg_mask |= (1 << 0);
> +               return 0;
> +       }
> +
> +       if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) {
> +               *ib_reg_mask |= (1 << 2);
> +               return 2;
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static void xgene_pcie_setup_ib_reg(struct xgene_pcie_port *port,
> +                                   struct of_pci_range *range, u8 *ib_reg_mask)
> +{
> +       void __iomem *csr_base = port->csr_base;
> +       void __iomem *cfg_base = port->cfg_base;
> +       void *bar_addr;
> +       void *pim_addr;
> +       u64 cpu_addr = range->cpu_addr;
> +       u64 pci_addr = range->pci_addr;
> +       u64 size = range->size;
> +       u64 mask = ~(size - 1) | EN_REG;
> +       u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
> +       u32 bar_low;
> +       int region;
> +
> +       region = xgene_pcie_select_ib_reg(ib_reg_mask, range->size);
> +       if (region < 0) {
> +               dev_warn(port->dev, "invalid pcie dma-range config\n");
> +               return;
> +       }
> +
> +       if (range->flags & IORESOURCE_PREFETCH)
> +               flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
> +
> +       bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
> +       switch (region) {
> +       case 0:
> +               xgene_pcie_set_ib_mask(csr_base, BRIDGE_CFG_4, flags, size);
> +               bar_addr = cfg_base + PCI_BASE_ADDRESS_0;
> +               writel(bar_low, bar_addr);
> +               writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
> +               pim_addr = csr_base + PIM1_1L;
> +               break;
> +       case 1:
> +               bar_addr = csr_base + IBAR2;
> +               writel(bar_low, bar_addr);
> +               writel(lower_32_bits(mask), csr_base + IR2MSK);
> +               pim_addr = csr_base + PIM2_1L;
> +               break;
> +       case 2:
> +               bar_addr = csr_base + IBAR3L;
> +               writel(bar_low, bar_addr);
> +               writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
> +               writel(lower_32_bits(mask), csr_base + IR3MSKL);
> +               writel(upper_32_bits(mask), csr_base + IR3MSKL + 0x4);
> +               pim_addr = csr_base + PIM3_1L;
> +               break;
> +       }
> +
> +       xgene_pcie_setup_pims(pim_addr, pci_addr, ~(size - 1));
> +}
> +
> +static int pci_dma_range_parser_init(struct of_pci_range_parser *parser,
> +                                    struct device_node *node)
> +{
> +       const int na = 3, ns = 2;
> +       int rlen;
> +
> +       parser->node = node;
> +       parser->pna = of_n_addr_cells(node);
> +       parser->np = parser->pna + na + ns;
> +
> +       parser->range = of_get_property(node, "dma-ranges", &rlen);
> +       if (!parser->range)
> +               return -ENOENT;
> +       parser->end = parser->range + rlen / sizeof(__be32);
> +
> +       return 0;
> +}
> +
> +static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie_port *port)
> +{
> +       struct device_node *np = port->node;
> +       struct of_pci_range range;
> +       struct of_pci_range_parser parser;
> +       struct device *dev = port->dev;
> +       u8 ib_reg_mask = 0;
> +
> +       if (pci_dma_range_parser_init(&parser, np)) {
> +               dev_err(dev, "missing dma-ranges property\n");
> +               return -EINVAL;
> +       }
> +
> +       /* Get the dma-ranges from DT */
> +       for_each_of_pci_range(&parser, &range) {
> +               u64 end = range.cpu_addr + range.size - 1;
> +
> +               dev_dbg(port->dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n",
> +                       range.flags, range.cpu_addr, end, range.pci_addr);
> +               xgene_pcie_setup_ib_reg(port, &range, &ib_reg_mask);
> +       }
> +       return 0;
> +}
> +
> +/* clear bar configuration which was done by firmware */
> +static void xgene_pcie_clear_config(struct xgene_pcie_port *port)
> +{
> +       int i;
> +
> +       for (i = PIM1_1L; i <= CFGCTL; i += 4)
> +               writel(0x0, port->csr_base + i);
> +}
> +
> +static int xgene_pcie_setup(struct xgene_pcie_port *port,
> +                           struct list_head *res,
> +                           resource_size_t io_base)
> +{
> +       u32 lanes = 0, speed = 0;
> +       int ret;
> +
> +       xgene_pcie_clear_config(port);
> +
> +       ret = xgene_pcie_map_ranges(port, res, io_base);
> +       if (ret)
> +               return ret;
> +
> +       ret = xgene_pcie_parse_map_dma_ranges(port);
> +       if (ret)
> +               return ret;
> +
> +       xgene_pcie_linkup(port, &lanes, &speed);
> +       if (!port->link_up)
> +               dev_info(port->dev, "(rc) link down\n");
> +       else
> +               dev_info(port->dev, "(rc) x%d gen-%d link up\n",
> +                               lanes, speed + 1);
> +       return 0;
> +}
> +
> +static int xgene_pcie_probe_bridge(struct platform_device *pdev)
> +{
> +       struct device_node *dn = pdev->dev.of_node;
> +       struct xgene_pcie_port *port;
> +       resource_size_t iobase = 0;
> +       struct pci_bus *bus;
> +       int ret;
> +       LIST_HEAD(res);
> +
> +       port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
> +       if (!port)
> +               return -ENOMEM;
> +       port->node = of_node_get(pdev->dev.of_node);
> +       port->dev = &pdev->dev;
> +
> +       ret = xgene_pcie_map_reg(port, pdev);
> +       if (ret)
> +               return ret;
> +
> +       ret = xgene_pcie_init_port(port);
> +       if (ret)
> +               return ret;
> +
> +       ret = of_pci_get_host_bridge_resources(dn, 0, 0xff, &res, &iobase);
> +       if (ret)
> +               return ret;
> +
> +       ret = xgene_pcie_setup(port, &res, iobase);
> +       if (ret)
> +               return ret;
> +
> +       bus = pci_scan_root_bus(&pdev->dev, 0, &xgene_pcie_ops, port, &res);
> +       if (!bus)
> +               return -ENOMEM;
> +
> +       platform_set_drvdata(pdev, port);
> +       return 0;
> +}
> +
> +static const struct of_device_id xgene_pcie_match_table[] = {
> +       {.compatible = "apm,xgene-pcie",},
> +       {},
> +};
> +
> +static struct platform_driver xgene_pcie_driver = {
> +       .driver = {
> +                  .name = "xgene-pcie",
> +                  .owner = THIS_MODULE,
> +                  .of_match_table = of_match_ptr(xgene_pcie_match_table),
> +       },
> +       .probe = xgene_pcie_probe_bridge,
> +};
> +module_platform_driver(xgene_pcie_driver);
> +
> +MODULE_AUTHOR("Tanmay Inamdar <tinamdar@apm.com>");
> +MODULE_DESCRIPTION("APM X-Gene PCIe driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1
> 
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯