[PATCH v7] pcie: Add Xilinx PCIe Host Bridge IP driver

Srikanth Thokala sthokal at xilinx.com
Wed Sep 3 00:22:05 PDT 2014


Hi Bjorn,

I fixed the mentioned issues with build-bot in v7.  Could you please
take this patch?

Thanks
Srikanth

On Wed, Aug 20, 2014 at 9:56 PM, Srikanth Thokala <sthokal at xilinx.com> wrote:
> This is the driver for Xilinx AXI PCIe Host Bridge Soft IP
>
> Signed-off-by: Srikanth Thokala <sthokal at xilinx.com>
> Acked-by: Arnd Bergmann <arnd at arndb.de>
> ---
> Changes in v7:
> - Removed errors reported from build-bot.  The errors are
>   mainly due to same CONFIG_PCI_XILINX flag being used for
>   Zynq and Microblaze platforms.  So, renamed the driver
>   config flag name to CONFIG_PCIE_XILINX.
> - Also, renamed the driver file to pcie-xilinx.c to be in
>   sync with CONFIG option.
> - Fixed the annotation of xilinx_pcie_scan_bus() function
>   to remove build-bot warnings.
>
> Changes in v6:
> - Added Ack from Arnd. Thanks Arnd.
> - Rebased on 3.16-rc7.
>
> Changes in v5:
> - Removed unnecessary checking of port structure.
> - Changed the return type of verify_config from int to bool.
> - Renamed following functions,
>   xilinx_pcie_is_link_up() -> xilinx_pcie_link_is_up()
>   xilinx_pcie_verify_config() -> xilinx_pcie_valid_device()
>   xilinx_pcie_get_config_base() -> xilinx_pcie_config_base()
> - Removed link_up bool flag from port structure, as it is not
>   being used.
> - Removed unused constants.
> - Rebased on 3.16-rc6.
> - Fixed some minor comments.
> - Thanks Bjorn for the review.
>
> Changes in v4:
> - Regarding the comments to separate ECAM functionality,
>   I have sent a separate patch and it is decided to implement
>   it later. The patch is here,
>   https://lkml.org/lkml/2014/5/18/54
> - Fixed issue with adding configuration bus resource.
> - Moved the logic for setting up bus resources to probe() from
>   pcie_setup().
> - Instead of mapping all the MSI interrupts in the probe, changed
>   to map only when a MSI is requested.
> - Earlier, the implementation of legacy and MSI interrupts init-
>   is mutually exclusive, now changed to have the legacy interrupts
>   init always and MSI interrupt init based on CONFIG_PCI_MSI flag.
> - Regarding the MSI generic implementation comment, I will plan to
>   do on top of this driver patch.
> - Rebased on 3.16-rc2.
> - Fixed other minor comments.
> - Thanks Arnd and Bjorn for the review.
>
> Changes in v3:
> - Rebased on v3.15.0-rc1
> - Added support for interrupt-map DT functionality.
> - Removed map_irq() wrapper, instead using of_irq_parse_and_map_pci().
> - Modified resource mapping logic as per the series
>   "PCI: ARM: add support for generic PCI host controller"
> - Modified devicetree binding documentation to update with interrupt-
>   map properties.
> - Use devm calls wherever applicable.
> - Fixed minor comments from Jason
> - Thanks Jason for the review and suggestions.
>
> Changes in v2:
> - Rebased on v3.14.0-rc8
> - Removed IP specific DT properties like include-rc, axibar-num etc.,
>   as suggested by Jason and Bjorn, Thanks
> ---
>  .../devicetree/bindings/pci/xilinx-pcie.txt        |   62 ++
>  drivers/pci/host/Kconfig                           |    7 +
>  drivers/pci/host/Makefile                          |    1 +
>  drivers/pci/host/pcie-xilinx.c                     |  978 ++++++++++++++++++++
>  4 files changed, 1048 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pci/xilinx-pcie.txt
>  create mode 100644 drivers/pci/host/pcie-xilinx.c
>
> diff --git a/Documentation/devicetree/bindings/pci/xilinx-pcie.txt b/Documentation/devicetree/bindings/pci/xilinx-pcie.txt
> new file mode 100644
> index 0000000..3e2c88d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/xilinx-pcie.txt
> @@ -0,0 +1,62 @@
> +* Xilinx AXI PCIe Root Port Bridge DT description
> +
> +Required properties:
> +- #address-cells: Address representation for root ports, set to <3>
> +- #size-cells: Size representation for root ports, set to <2>
> +- #interrupt-cells: specifies the number of cells needed to encode an
> +       interrupt source. The value must be 1.
> +- compatible: Should contain "xlnx,axi-pcie-host-1.00.a"
> +- reg: Should contain AXI PCIe registers location and length
> +- device_type: must be "pci"
> +- interrupts: Should contain AXI PCIe interrupt
> +- interrupt-map-mask,
> +  interrupt-map: standard PCI properties to define the mapping of the
> +       PCI interface to interrupt numbers.
> +- ranges: ranges for the PCI memory regions (I/O space region is not
> +       supported by hardware)
> +       Please refer to the standard PCI bus binding document for a more
> +       detailed explanation
> +
> +Optional properties:
> +- bus-range: PCI bus numbers covered
> +
> +Interrupt controller child node
> ++++++++++++++++++++++++++++++++
> +Required properties:
> +- interrupt-controller: identifies the node as an interrupt controller
> +- #address-cells: specifies the number of cells needed to encode an
> +       address. The value must be 0.
> +- #interrupt-cells: specifies the number of cells needed to encode an
> +       interrupt source. The value must be 1.
> +
> +NOTE:
> +The core provides a single interrupt for both INTx/MSI messages. So,
> +created a interrupt controller node to support 'interrupt-map' DT
> +functionality.  The driver will create an IRQ domain for this map, decode
> +the four INTx interrupts in ISR and route them to this domain.
> +
> +
> +Example:
> +++++++++
> +
> +       pci_express: axi-pcie at 50000000 {
> +               #address-cells = <3>;
> +               #size-cells = <2>;
> +               #interrupt-cells = <1>;
> +               compatible = "xlnx,axi-pcie-host-1.00.a";
> +               reg = < 0x50000000 0x10000000 >;
> +               device_type = "pci";
> +               interrupts = < 0 52 4 >;
> +               interrupt-map-mask = <0 0 0 7>;
> +               interrupt-map = <0 0 0 1 &pcie_intc 1>,
> +                               <0 0 0 2 &pcie_intc 2>,
> +                               <0 0 0 3 &pcie_intc 3>,
> +                               <0 0 0 4 &pcie_intc 4>;
> +               ranges = < 0x02000000 0 0x60000000 0x60000000 0 0x10000000 >;
> +
> +               pcie_intc: interrupt-controller {
> +                       interrupt-controller;
> +                       #address-cells = <0>;
> +                       #interrupt-cells = <1>;
> +               }
> +       };
> diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
> index 21df477..255a9fa 100644
> --- a/drivers/pci/host/Kconfig
> +++ b/drivers/pci/host/Kconfig
> @@ -46,4 +46,11 @@ config PCI_HOST_GENERIC
>           Say Y here if you want to support a simple generic PCI host
>           controller, such as the one emulated by kvmtool.
>
> +config PCIE_XILINX
> +       bool "Xilinx AXI PCIe host bridge support"
> +       depends on ARCH_ZYNQ
> +       help
> +         Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
> +         Host Bridge driver.
> +
>  endmenu
> diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
> index 611ba4b..339595c 100644
> --- a/drivers/pci/host/Makefile
> +++ b/drivers/pci/host/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
>  obj-$(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_XILINX) += pcie-xilinx.o
> diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
> new file mode 100644
> index 0000000..32c5ded
> --- /dev/null
> +++ b/drivers/pci/host/pcie-xilinx.c
> @@ -0,0 +1,978 @@
> +/*
> + * PCIe host controller driver for Xilinx AXI PCIe Bridge
> + *
> + * Copyright (c) 2012 - 2014 Xilinx, Inc.
> + *
> + * Based on the Tegra PCIe driver
> + *
> + * Bits taken from Synopsys Designware Host controller driver and
> + * ARM PCI Host generic driver.
> + *
> + * 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.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/msi.h>
> +#include <linux/of_address.h>
> +#include <linux/of_pci.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +
> +/* Register definitions */
> +#define XILINX_PCIE_REG_BIR            0x00000130
> +#define XILINX_PCIE_REG_IDR            0x00000138
> +#define XILINX_PCIE_REG_IMR            0x0000013c
> +#define XILINX_PCIE_REG_PSCR           0x00000144
> +#define XILINX_PCIE_REG_RPSC           0x00000148
> +#define XILINX_PCIE_REG_MSIBASE1       0x0000014c
> +#define XILINX_PCIE_REG_MSIBASE2       0x00000150
> +#define XILINX_PCIE_REG_RPEFR          0x00000154
> +#define XILINX_PCIE_REG_RPIFR1         0x00000158
> +#define XILINX_PCIE_REG_RPIFR2         0x0000015c
> +
> +/* Interrupt registers definitions */
> +#define XILINX_PCIE_INTR_LINK_DOWN     BIT(0)
> +#define XILINX_PCIE_INTR_ECRC_ERR      BIT(1)
> +#define XILINX_PCIE_INTR_STR_ERR       BIT(2)
> +#define XILINX_PCIE_INTR_HOT_RESET     BIT(3)
> +#define XILINX_PCIE_INTR_CFG_TIMEOUT   BIT(8)
> +#define XILINX_PCIE_INTR_CORRECTABLE   BIT(9)
> +#define XILINX_PCIE_INTR_NONFATAL      BIT(10)
> +#define XILINX_PCIE_INTR_FATAL         BIT(11)
> +#define XILINX_PCIE_INTR_INTX          BIT(16)
> +#define XILINX_PCIE_INTR_MSI           BIT(17)
> +#define XILINX_PCIE_INTR_SLV_UNSUPP    BIT(20)
> +#define XILINX_PCIE_INTR_SLV_UNEXP     BIT(21)
> +#define XILINX_PCIE_INTR_SLV_COMPL     BIT(22)
> +#define XILINX_PCIE_INTR_SLV_ERRP      BIT(23)
> +#define XILINX_PCIE_INTR_SLV_CMPABT    BIT(24)
> +#define XILINX_PCIE_INTR_SLV_ILLBUR    BIT(25)
> +#define XILINX_PCIE_INTR_MST_DECERR    BIT(26)
> +#define XILINX_PCIE_INTR_MST_SLVERR    BIT(27)
> +#define XILINX_PCIE_INTR_MST_ERRP      BIT(28)
> +#define XILINX_PCIE_IMR_ALL_MASK       0x1FF30FED
> +#define XILINX_PCIE_IDR_ALL_MASK       0xFFFFFFFF
> +
> +/* Root Port Error FIFO Read Register definitions */
> +#define XILINX_PCIE_RPEFR_ERR_VALID    BIT(18)
> +#define XILINX_PCIE_RPEFR_REQ_ID       GENMASK(15, 0)
> +#define XILINX_PCIE_RPEFR_ALL_MASK     0xFFFFFFFF
> +
> +/* Root Port Interrupt FIFO Read Register 1 definitions */
> +#define XILINX_PCIE_RPIFR1_INTR_VALID  BIT(31)
> +#define XILINX_PCIE_RPIFR1_MSI_INTR    BIT(30)
> +#define XILINX_PCIE_RPIFR1_INTR_MASK   GENMASK(28, 27)
> +#define XILINX_PCIE_RPIFR1_ALL_MASK    0xFFFFFFFF
> +#define XILINX_PCIE_RPIFR1_INTR_SHIFT          27
> +
> +/* Bridge Info Register definitions */
> +#define XILINX_PCIE_BIR_ECAM_SZ_MASK   GENMASK(18, 16)
> +#define XILINX_PCIE_BIR_ECAM_SZ_SHIFT  16
> +
> +/* Root Port Interrupt FIFO Read Register 2 definitions */
> +#define XILINX_PCIE_RPIFR2_MSG_DATA    GENMASK(15, 0)
> +
> +/* Root Port Status/control Register definitions */
> +#define XILINX_PCIE_REG_RPSC_BEN       BIT(0)
> +
> +/* Phy Status/Control Register definitions */
> +#define XILINX_PCIE_REG_PSCR_LNKUP     BIT(11)
> +
> +/* ECAM definitions */
> +#define ECAM_BUS_NUM_SHIFT             20
> +#define ECAM_DEV_NUM_SHIFT             12
> +
> +/* Number of MSI IRQs */
> +#define XILINX_NUM_MSI_IRQS            128
> +
> +/* Number of Memory Resources */
> +#define XILINX_MAX_NUM_RESOURCES       3
> +
> +/**
> + * struct xilinx_pcie_port - PCIe port information
> + * @reg_base: IO Mapped Register Base
> + * @irq: Interrupt number
> + * @msi_pages: MSI pages
> + * @root_busno: Root Bus number
> + * @dev: Device pointer
> + * @irq_domain: IRQ domain pointer
> + * @bus_range: Bus range
> + * @resources: Bus Resources
> + */
> +struct xilinx_pcie_port {
> +       void __iomem *reg_base;
> +       u32 irq;
> +       unsigned long msi_pages;
> +       u8 root_busno;
> +       struct device *dev;
> +       struct irq_domain *irq_domain;
> +       struct resource bus_range;
> +       struct list_head resources;
> +};
> +
> +static DECLARE_BITMAP(msi_irq_in_use, XILINX_NUM_MSI_IRQS);
> +
> +static inline struct xilinx_pcie_port *sys_to_pcie(struct pci_sys_data *sys)
> +{
> +       return sys->private_data;
> +}
> +
> +static inline u32 pcie_read(struct xilinx_pcie_port *port, u32 reg)
> +{
> +       return readl(port->reg_base + reg);
> +}
> +
> +static inline void pcie_write(struct xilinx_pcie_port *port,
> +                             u32 val, u32 reg)
> +{
> +       writel(val, port->reg_base + reg);
> +}
> +
> +static inline bool xilinx_pcie_link_is_up(struct xilinx_pcie_port *port)
> +{
> +       return (pcie_read(port, XILINX_PCIE_REG_PSCR) &
> +               XILINX_PCIE_REG_PSCR_LNKUP) ? 1 : 0;
> +}
> +
> +/**
> + * xilinx_pcie_clear_err_interrupts - Clear Error Interrupts
> + * @port: PCIe port information
> + */
> +static void xilinx_pcie_clear_err_interrupts(struct xilinx_pcie_port *port)
> +{
> +       u32 val = pcie_read(port, XILINX_PCIE_REG_RPEFR);
> +
> +       if (val & XILINX_PCIE_RPEFR_ERR_VALID) {
> +               dev_dbg(port->dev, "Requester ID %d\n",
> +                       val & XILINX_PCIE_RPEFR_REQ_ID);
> +               pcie_write(port, XILINX_PCIE_RPEFR_ALL_MASK,
> +                          XILINX_PCIE_REG_RPEFR);
> +       }
> +}
> +
> +/**
> + * xilinx_pcie_valid_device - Check if a valid device is present on bus
> + * @bus: PCI Bus structure
> + * @devfn: device/function
> + *
> + * Return: 'true' on success and 'false' if invalid device is found
> + */
> +static bool xilinx_pcie_valid_device(struct pci_bus *bus,
> +                                    unsigned int devfn)
> +{
> +       struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
> +
> +       /* Check if link is up when trying to access downstream ports */
> +       if (bus->number != port->root_busno)
> +               if (!xilinx_pcie_link_is_up(port))
> +                       return false;
> +
> +       /* Only one device down on each root port */
> +       if (bus->number == port->root_busno && devfn > 0)
> +               return false;
> +
> +       /*
> +        * Do not read more than one device on the bus directly attached
> +        * to RC.
> +        */
> +       if (bus->primary == port->root_busno && devfn > 0)
> +               return false;
> +
> +       return true;
> +}
> +
> +/**
> + * xilinx_pcie_config_base - Get configuration base
> + * @bus: PCI Bus structure
> + * @devfn: Device/function
> + * @where: Offset from base
> + *
> + * Return: Base address of the configuration space needed to be
> + *        accessed.
> + */
> +static void __iomem *xilinx_pcie_config_base(struct pci_bus *bus,
> +                                                unsigned int devfn,
> +                                                int where)
> +{
> +       struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
> +       int relbus;
> +
> +       relbus = (bus->number << ECAM_BUS_NUM_SHIFT) |
> +                (devfn << ECAM_DEV_NUM_SHIFT);
> +
> +       return port->reg_base + relbus + where;
> +}
> +
> +/**
> + * xilinx_pcie_read_config - Read configuration space
> + * @bus: PCI Bus structure
> + * @devfn: Device/function
> + * @where: Offset from base
> + * @size: Byte/word/dword
> + * @val: Value to be read
> + *
> + * Return: PCIBIOS_SUCCESSFUL on success
> + *        EINVAL/PCIBIOS_DEVICE_NOT_FOUND/PCIBIOS_BAD_REGISTER_NUMBER
> + *        on failure.
> + */
> +static int xilinx_pcie_read_config(struct pci_bus *bus,
> +                                  unsigned int devfn, int where,
> +                                  int size, u32 *val)
> +{
> +       void __iomem *addr;
> +
> +       if (!xilinx_pcie_valid_device(bus, devfn)) {
> +               *val = 0xFFFFFFFF;
> +               return PCIBIOS_DEVICE_NOT_FOUND;
> +       }
> +
> +       addr = xilinx_pcie_config_base(bus, devfn, where);
> +
> +       switch (size) {
> +       case 1:
> +               *val = readb(addr);
> +               break;
> +       case 2:
> +               *val = readw(addr);
> +               break;
> +       default:
> +               *val = readl(addr);
> +               break;
> +       }
> +
> +       return PCIBIOS_SUCCESSFUL;
> +}
> +
> +/**
> + * xilinx_pcie_write_config - Write configuration space
> + * @bus: PCI Bus structure
> + * @devfn: Device/function
> + * @where: Offset from base
> + * @size: Byte/word/dword
> + * @val: Value to be written to device
> + *
> + * Return: PCIBIOS_SUCCESSFUL on success,
> + *        EINVAL/PCIBIOS_DEVICE_NOT_FOUND/PCIBIOS_BAD_REGISTER_NUMBER
> + *        on failure.
> + */
> +static int xilinx_pcie_write_config(struct pci_bus *bus,
> +                                   unsigned int devfn, int where,
> +                                   int size, u32 val)
> +{
> +       void __iomem *addr;
> +
> +       if (!xilinx_pcie_valid_device(bus, devfn))
> +               return PCIBIOS_DEVICE_NOT_FOUND;
> +
> +       addr = xilinx_pcie_config_base(bus, devfn, where);
> +
> +       switch (size) {
> +       case 1:
> +               writeb(val, addr);
> +               break;
> +       case 2:
> +               writew(val, addr);
> +               break;
> +       default:
> +               writel(val, addr);
> +               break;
> +       }
> +
> +       return PCIBIOS_SUCCESSFUL;
> +}
> +
> +/* PCIe operations */
> +static struct pci_ops xilinx_pcie_ops = {
> +       .read  = xilinx_pcie_read_config,
> +       .write = xilinx_pcie_write_config,
> +};
> +
> +/* MSI functions */
> +
> +/**
> + * xilinx_pcie_destroy_msi - Free MSI number
> + * @irq: IRQ to be freed
> + */
> +static void xilinx_pcie_destroy_msi(unsigned int irq)
> +{
> +       struct irq_desc *desc;
> +       struct msi_desc *msi;
> +       struct xilinx_pcie_port *port;
> +
> +       desc = irq_to_desc(irq);
> +       msi = irq_desc_get_msi_desc(desc);
> +       port = sys_to_pcie(msi->dev->bus->sysdata);
> +
> +       if (!test_bit(irq, msi_irq_in_use))
> +               dev_err(port->dev, "Trying to free unused MSI#%d\n", irq);
> +       else
> +               clear_bit(irq, msi_irq_in_use);
> +}
> +
> +/**
> + * xilinx_pcie_assign_msi - Allocate MSI number
> + * @port: PCIe port structure
> + *
> + * Return: A valid IRQ on success and error value on failure.
> + */
> +static int xilinx_pcie_assign_msi(struct xilinx_pcie_port *port)
> +{
> +       int pos;
> +
> +       pos = find_first_zero_bit(msi_irq_in_use, XILINX_NUM_MSI_IRQS);
> +       if (pos < XILINX_NUM_MSI_IRQS)
> +               set_bit(pos, msi_irq_in_use);
> +       else
> +               return -ENOSPC;
> +
> +       return pos;
> +}
> +
> +/**
> + * xilinx_msi_teardown_irq - Destroy the MSI
> + * @chip: MSI Chip descriptor
> + * @irq: MSI IRQ to destroy
> + */
> +static void xilinx_msi_teardown_irq(struct msi_chip *chip, unsigned int irq)
> +{
> +       xilinx_pcie_destroy_msi(irq);
> +}
> +
> +/**
> + * xilinx_pcie_msi_setup_irq - Setup MSI request
> + * @chip: MSI chip pointer
> + * @pdev: PCIe device pointer
> + * @desc: MSI descriptor pointer
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_pcie_msi_setup_irq(struct msi_chip *chip,
> +                                    struct pci_dev *pdev,
> +                                    struct msi_desc *desc)
> +{
> +       struct xilinx_pcie_port *port = sys_to_pcie(pdev->bus->sysdata);
> +       unsigned int irq;
> +       int hwirq;
> +       struct msi_msg msg;
> +       phys_addr_t msg_addr;
> +
> +       hwirq = xilinx_pcie_assign_msi(port);
> +       if (irq < 0)
> +               return irq;
> +
> +       irq = irq_create_mapping(port->irq_domain, hwirq);
> +       if (!irq)
> +               return -EINVAL;
> +
> +       irq_set_msi_desc(irq, desc);
> +
> +       msg_addr = virt_to_phys((void *)port->msi_pages);
> +
> +       msg.address_hi = 0;
> +       msg.address_lo = msg_addr;
> +       msg.data = irq;
> +
> +       write_msi_msg(irq, &msg);
> +
> +       return 0;
> +}
> +
> +/* MSI Chip Descriptor */
> +static struct msi_chip xilinx_pcie_msi_chip = {
> +       .setup_irq = xilinx_pcie_msi_setup_irq,
> +       .teardown_irq = xilinx_msi_teardown_irq,
> +};
> +
> +/* HW Interrupt Chip Descriptor */
> +static struct irq_chip xilinx_msi_irq_chip = {
> +       .name = "Xilinx PCIe MSI",
> +       .irq_enable = unmask_msi_irq,
> +       .irq_disable = mask_msi_irq,
> +       .irq_mask = mask_msi_irq,
> +       .irq_unmask = unmask_msi_irq,
> +};
> +
> +/**
> + * xilinx_pcie_msi_map - Set the handler for the MSI and mark IRQ as valid
> + * @domain: IRQ domain
> + * @irq: Virtual IRQ number
> + * @hwirq: HW interrupt number
> + *
> + * Return: Always returns 0.
> + */
> +static int xilinx_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
> +                              irq_hw_number_t hwirq)
> +{
> +       irq_set_chip_and_handler(irq, &xilinx_msi_irq_chip, handle_simple_irq);
> +       irq_set_chip_data(irq, domain->host_data);
> +       set_irq_flags(irq, IRQF_VALID);
> +
> +       return 0;
> +}
> +
> +/* IRQ Domain operations */
> +static const struct irq_domain_ops msi_domain_ops = {
> +       .map = xilinx_pcie_msi_map,
> +};
> +
> +/**
> + * xilinx_pcie_enable_msi - Enable MSI support
> + * @port: PCIe port information
> + */
> +static void xilinx_pcie_enable_msi(struct xilinx_pcie_port *port)
> +{
> +       phys_addr_t msg_addr;
> +
> +       port->msi_pages = __get_free_pages(GFP_KERNEL, 0);
> +       msg_addr = virt_to_phys((void *)port->msi_pages);
> +       pcie_write(port, 0x0, XILINX_PCIE_REG_MSIBASE1);
> +       pcie_write(port, msg_addr, XILINX_PCIE_REG_MSIBASE2);
> +}
> +
> +/**
> + * xilinx_pcie_add_bus - Add MSI chip info to PCIe bus
> + * @bus: PCIe bus
> + */
> +static void xilinx_pcie_add_bus(struct pci_bus *bus)
> +{
> +       if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +               struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
> +
> +               xilinx_pcie_msi_chip.dev = port->dev;
> +               bus->msi = &xilinx_pcie_msi_chip;
> +       }
> +}
> +
> +/* INTx Functions */
> +
> +/**
> + * xilinx_pcie_intx_map - Set the handler for the INTx and mark IRQ as valid
> + * @domain: IRQ domain
> + * @irq: Virtual IRQ number
> + * @hwirq: HW interrupt number
> + *
> + * Return: Always returns 0.
> + */
> +static int xilinx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
> +                               irq_hw_number_t hwirq)
> +{
> +       irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
> +       irq_set_chip_data(irq, domain->host_data);
> +       set_irq_flags(irq, IRQF_VALID);
> +
> +       return 0;
> +}
> +
> +/* INTx IRQ Domain operations */
> +static const struct irq_domain_ops intx_domain_ops = {
> +       .map = xilinx_pcie_intx_map,
> +};
> +
> +/* PCIe HW Functions */
> +
> +/**
> + * xilinx_pcie_intr_handler - Interrupt Service Handler
> + * @irq: IRQ number
> + * @data: PCIe port information
> + *
> + * Return: IRQ_HANDLED on success and IRQ_NONE on failure
> + */
> +static irqreturn_t xilinx_pcie_intr_handler(int irq, void *data)
> +{
> +       struct xilinx_pcie_port *port = (struct xilinx_pcie_port *)data;
> +       u32 val, mask, status, msi_data;
> +
> +       /* Read interrupt decode and mask registers */
> +       val = pcie_read(port, XILINX_PCIE_REG_IDR);
> +       mask = pcie_read(port, XILINX_PCIE_REG_IMR);
> +
> +       status = val & mask;
> +       if (!status)
> +               return IRQ_NONE;
> +
> +       if (status & XILINX_PCIE_INTR_LINK_DOWN)
> +               dev_warn(port->dev, "Link Down\n");
> +
> +       if (status & XILINX_PCIE_INTR_ECRC_ERR)
> +               dev_warn(port->dev, "ECRC failed\n");
> +
> +       if (status & XILINX_PCIE_INTR_STR_ERR)
> +               dev_warn(port->dev, "Streaming error\n");
> +
> +       if (status & XILINX_PCIE_INTR_HOT_RESET)
> +               dev_info(port->dev, "Hot reset\n");
> +
> +       if (status & XILINX_PCIE_INTR_CFG_TIMEOUT)
> +               dev_warn(port->dev, "ECAM access timeout\n");
> +
> +       if (status & XILINX_PCIE_INTR_CORRECTABLE) {
> +               dev_warn(port->dev, "Correctable error message\n");
> +               xilinx_pcie_clear_err_interrupts(port);
> +       }
> +
> +       if (status & XILINX_PCIE_INTR_NONFATAL) {
> +               dev_warn(port->dev, "Non fatal error message\n");
> +               xilinx_pcie_clear_err_interrupts(port);
> +       }
> +
> +       if (status & XILINX_PCIE_INTR_FATAL) {
> +               dev_warn(port->dev, "Fatal error message\n");
> +               xilinx_pcie_clear_err_interrupts(port);
> +       }
> +
> +       if (status & XILINX_PCIE_INTR_INTX) {
> +               /* INTx interrupt received */
> +               val = pcie_read(port, XILINX_PCIE_REG_RPIFR1);
> +
> +               /* Check whether interrupt valid */
> +               if (!(val & XILINX_PCIE_RPIFR1_INTR_VALID)) {
> +                       dev_warn(port->dev, "RP Intr FIFO1 read error\n");
> +                       return IRQ_HANDLED;
> +               }
> +
> +               /* Clear interrupt FIFO register 1 */
> +               pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK,
> +                          XILINX_PCIE_REG_RPIFR1);
> +
> +               /* Handle INTx Interrupt */
> +               val = ((val & XILINX_PCIE_RPIFR1_INTR_MASK) >>
> +                       XILINX_PCIE_RPIFR1_INTR_SHIFT) + 1;
> +               generic_handle_irq(irq_find_mapping(port->irq_domain, val));
> +       }
> +
> +       if (status & XILINX_PCIE_INTR_MSI) {
> +               /* MSI Interrupt */
> +               val = pcie_read(port, XILINX_PCIE_REG_RPIFR1);
> +
> +               if (!(val & XILINX_PCIE_RPIFR1_INTR_VALID)) {
> +                       dev_warn(port->dev, "RP Intr FIFO1 read error\n");
> +                       return IRQ_HANDLED;
> +               }
> +
> +               if (val & XILINX_PCIE_RPIFR1_MSI_INTR) {
> +                       msi_data = pcie_read(port, XILINX_PCIE_REG_RPIFR2) &
> +                                  XILINX_PCIE_RPIFR2_MSG_DATA;
> +
> +                       /* Clear interrupt FIFO register 1 */
> +                       pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK,
> +                                  XILINX_PCIE_REG_RPIFR1);
> +
> +                       if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +                               /* Handle MSI Interrupt */
> +                               generic_handle_irq(msi_data);
> +                       }
> +               }
> +       }
> +
> +       if (status & XILINX_PCIE_INTR_SLV_UNSUPP)
> +               dev_warn(port->dev, "Slave unsupported request\n");
> +
> +       if (status & XILINX_PCIE_INTR_SLV_UNEXP)
> +               dev_warn(port->dev, "Slave unexpected completion\n");
> +
> +       if (status & XILINX_PCIE_INTR_SLV_COMPL)
> +               dev_warn(port->dev, "Slave completion timeout\n");
> +
> +       if (status & XILINX_PCIE_INTR_SLV_ERRP)
> +               dev_warn(port->dev, "Slave Error Poison\n");
> +
> +       if (status & XILINX_PCIE_INTR_SLV_CMPABT)
> +               dev_warn(port->dev, "Slave Completer Abort\n");
> +
> +       if (status & XILINX_PCIE_INTR_SLV_ILLBUR)
> +               dev_warn(port->dev, "Slave Illegal Burst\n");
> +
> +       if (status & XILINX_PCIE_INTR_MST_DECERR)
> +               dev_warn(port->dev, "Master decode error\n");
> +
> +       if (status & XILINX_PCIE_INTR_MST_SLVERR)
> +               dev_warn(port->dev, "Master slave error\n");
> +
> +       if (status & XILINX_PCIE_INTR_MST_ERRP)
> +               dev_warn(port->dev, "Master error poison\n");
> +
> +       /* Clear the Interrupt Decode register */
> +       pcie_write(port, status, XILINX_PCIE_REG_IDR);
> +
> +       return IRQ_HANDLED;
> +}
> +
> +/**
> + * xilinx_pcie_free_irq_domain - Free IRQ domain
> + * @port: PCIe port information
> + */
> +static void xilinx_pcie_free_irq_domain(struct xilinx_pcie_port *port)
> +{
> +       int i;
> +       u32 irq, num_irqs;
> +
> +       /* Free IRQ Domain */
> +       if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +
> +               free_pages(port->msi_pages, 0);
> +
> +               num_irqs = XILINX_NUM_MSI_IRQS;
> +       } else {
> +               /* INTx */
> +               num_irqs = 4;
> +       }
> +
> +       for (i = 0; i < num_irqs; i++) {
> +               irq = irq_find_mapping(port->irq_domain, i);
> +               if (irq > 0)
> +                       irq_dispose_mapping(irq);
> +       }
> +
> +       irq_domain_remove(port->irq_domain);
> +}
> +
> +/**
> + * xilinx_pcie_init_irq_domain - Initialize IRQ domain
> + * @port: PCIe port information
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
> +{
> +       struct device *dev = port->dev;
> +       struct device_node *node = dev->of_node;
> +       struct device_node *pcie_intc_node;
> +
> +       /* Setup INTx */
> +       pcie_intc_node = of_get_next_child(node, NULL);
> +       if (!pcie_intc_node) {
> +               dev_err(dev, "No PCIe Intc node found\n");
> +               return PTR_ERR(pcie_intc_node);
> +       }
> +
> +       port->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
> +                                                &intx_domain_ops,
> +                                                port);
> +       if (!port->irq_domain) {
> +               dev_err(dev, "Failed to get a INTx IRQ domain\n");
> +               return PTR_ERR(port->irq_domain);
> +       }
> +
> +       /* Setup MSI */
> +       if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +               port->irq_domain = irq_domain_add_linear(node,
> +                                                        XILINX_NUM_MSI_IRQS,
> +                                                        &msi_domain_ops,
> +                                                        &xilinx_pcie_msi_chip);
> +               if (!port->irq_domain) {
> +                       dev_err(dev, "Failed to get a MSI IRQ domain\n");
> +                       return PTR_ERR(port->irq_domain);
> +               }
> +
> +               xilinx_pcie_enable_msi(port);
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * xilinx_pcie_init_port - Initialize hardware
> + * @port: PCIe port information
> + */
> +static void xilinx_pcie_init_port(struct xilinx_pcie_port *port)
> +{
> +       if (xilinx_pcie_link_is_up(port))
> +               dev_info(port->dev, "PCIe Link is UP\n");
> +       else
> +               dev_info(port->dev, "PCIe Link is DOWN\n");
> +
> +       /* Disable all interrupts */
> +       pcie_write(port, ~XILINX_PCIE_IDR_ALL_MASK,
> +                  XILINX_PCIE_REG_IMR);
> +
> +       /* Clear pending interrupts */
> +       pcie_write(port, pcie_read(port, XILINX_PCIE_REG_IDR) &
> +                        XILINX_PCIE_IMR_ALL_MASK,
> +                  XILINX_PCIE_REG_IDR);
> +
> +       /* Enable all interrupts */
> +       pcie_write(port, XILINX_PCIE_IMR_ALL_MASK, XILINX_PCIE_REG_IMR);
> +
> +       /* Enable the Bridge enable bit */
> +       pcie_write(port, pcie_read(port, XILINX_PCIE_REG_RPSC) |
> +                        XILINX_PCIE_REG_RPSC_BEN,
> +                  XILINX_PCIE_REG_RPSC);
> +}
> +
> +/**
> + * xilinx_pcie_setup - Setup memory resources
> + * @nr: Bus number
> + * @sys: Per controller structure
> + *
> + * Return: '1' on success and error value on failure
> + */
> +static int xilinx_pcie_setup(int nr, struct pci_sys_data *sys)
> +{
> +       struct xilinx_pcie_port *port = sys_to_pcie(sys);
> +
> +       list_splice_init(&port->resources, &sys->resources);
> +
> +       return 1;
> +}
> +
> +/**
> + * xilinx_pcie_scan_bus - Scan PCIe bus for devices
> + * @nr: Bus number
> + * @sys: Per controller structure
> + *
> + * Return: Valid Bus pointer on success and NULL on failure
> + */
> +static struct pci_bus *xilinx_pcie_scan_bus(int nr,
> +                                                  struct pci_sys_data *sys)
> +{
> +       struct xilinx_pcie_port *port = sys_to_pcie(sys);
> +       struct pci_bus *bus;
> +
> +       port->root_busno = sys->busnr;
> +       bus = pci_scan_root_bus(port->dev, sys->busnr, &xilinx_pcie_ops,
> +                               sys, &sys->resources);
> +
> +       return bus;
> +}
> +
> +/**
> + * xilinx_pcie_parse_and_add_res - Add resources by parsing ranges
> + * @port: PCIe port information
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_pcie_parse_and_add_res(struct xilinx_pcie_port *port)
> +{
> +       struct device *dev = port->dev;
> +       struct device_node *node = dev->of_node;
> +       struct resource *mem;
> +       resource_size_t offset;
> +       struct of_pci_range_parser parser;
> +       struct of_pci_range range;
> +       struct pci_host_bridge_window *win;
> +       int err = 0, mem_resno = 0;
> +
> +       /* Get the ranges */
> +       if (of_pci_range_parser_init(&parser, node)) {
> +               dev_err(dev, "missing \"ranges\" property\n");
> +               return -EINVAL;
> +       }
> +
> +       /* Parse the ranges and add the resources found to the list */
> +       for_each_of_pci_range(&parser, &range) {
> +
> +               if (mem_resno >= XILINX_MAX_NUM_RESOURCES) {
> +                       dev_err(dev, "Maximum memory resources exceeded\n");
> +                       return -EINVAL;
> +               }
> +
> +               mem = devm_kmalloc(dev, sizeof(*mem), GFP_KERNEL);
> +               if (!mem) {
> +                       err = -ENOMEM;
> +                       goto free_resources;
> +               }
> +
> +               of_pci_range_to_resource(&range, node, mem);
> +
> +               switch (mem->flags & IORESOURCE_TYPE_BITS) {
> +               case IORESOURCE_MEM:
> +                       offset = range.cpu_addr - range.pci_addr;
> +                       mem_resno++;
> +                       break;
> +               default:
> +                       err = -EINVAL;
> +                       break;
> +               }
> +
> +               if (err < 0) {
> +                       dev_warn(dev, "Invalid resource found %pR\n", mem);
> +                       continue;
> +               }
> +
> +               err = request_resource(&iomem_resource, mem);
> +               if (err)
> +                       goto free_resources;
> +
> +               pci_add_resource_offset(&port->resources, mem, offset);
> +       }
> +
> +       /* Get the bus range */
> +       if (of_pci_parse_bus_range(node, &port->bus_range)) {
> +               u32 val = pcie_read(port, XILINX_PCIE_REG_BIR);
> +               u8 last;
> +
> +               last = (val & XILINX_PCIE_BIR_ECAM_SZ_MASK) >>
> +                       XILINX_PCIE_BIR_ECAM_SZ_SHIFT;
> +
> +               port->bus_range = (struct resource) {
> +                       .name   = node->name,
> +                       .start  = 0,
> +                       .end    = last,
> +                       .flags  = IORESOURCE_BUS,
> +               };
> +       }
> +
> +       /* Register bus resource */
> +       pci_add_resource(&port->resources, &port->bus_range);
> +
> +       return 0;
> +
> +free_resources:
> +       release_child_resources(&iomem_resource);
> +       list_for_each_entry(win, &port->resources, list)
> +               devm_kfree(dev, win->res);
> +       pci_free_resource_list(&port->resources);
> +
> +       return err;
> +}
> +
> +/**
> + * xilinx_pcie_parse_dt - Parse Device tree
> + * @port: PCIe port information
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port)
> +{
> +       struct device *dev = port->dev;
> +       struct device_node *node = dev->of_node;
> +       struct resource regs;
> +       const char *type;
> +       int err;
> +
> +       type = of_get_property(node, "device_type", NULL);
> +       if (!type || strcmp(type, "pci")) {
> +               dev_err(dev, "invalid \"device_type\" %s\n", type);
> +               return -EINVAL;
> +       }
> +
> +       err = of_address_to_resource(node, 0, &regs);
> +       if (err) {
> +               dev_err(dev, "missing \"reg\" property\n");
> +               return err;
> +       }
> +
> +       port->reg_base = devm_ioremap_resource(dev, &regs);
> +       if (IS_ERR(port->reg_base))
> +               return PTR_ERR(port->reg_base);
> +
> +       port->irq = irq_of_parse_and_map(node, 0);
> +       err = devm_request_irq(dev, port->irq, xilinx_pcie_intr_handler,
> +                              IRQF_SHARED, "xilinx-pcie", port);
> +       if (err) {
> +               dev_err(dev, "unable to request irq %d\n", port->irq);
> +               return err;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * xilinx_pcie_probe - Probe function
> + * @pdev: Platform device pointer
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_pcie_probe(struct platform_device *pdev)
> +{
> +       struct xilinx_pcie_port *port;
> +       struct hw_pci hw;
> +       struct device *dev = &pdev->dev;
> +       int err;
> +
> +       if (!dev->of_node)
> +               return -ENODEV;
> +
> +       port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
> +       if (!port)
> +               return -ENOMEM;
> +
> +       port->dev = dev;
> +
> +       err = xilinx_pcie_parse_dt(port);
> +       if (err) {
> +               dev_err(dev, "Parsing DT failed\n");
> +               return err;
> +       }
> +
> +       xilinx_pcie_init_port(port);
> +
> +       err = xilinx_pcie_init_irq_domain(port);
> +       if (err) {
> +               dev_err(dev, "Failed creating IRQ Domain\n");
> +               return err;
> +       }
> +
> +       /*
> +        * Parse PCI ranges, configuration bus range and
> +        * request their resources
> +        */
> +       INIT_LIST_HEAD(&port->resources);
> +       err = xilinx_pcie_parse_and_add_res(port);
> +       if (err) {
> +               dev_err(dev, "Failed adding resources\n");
> +               return err;
> +       }
> +
> +       platform_set_drvdata(pdev, port);
> +
> +       /* Register the device */
> +       memset(&hw, 0, sizeof(hw));
> +       hw = (struct hw_pci) {
> +               .nr_controllers = 1,
> +               .private_data   = (void **)&port,
> +               .setup          = xilinx_pcie_setup,
> +               .map_irq        = of_irq_parse_and_map_pci,
> +               .add_bus        = xilinx_pcie_add_bus,
> +               .scan           = xilinx_pcie_scan_bus,
> +               .ops            = &xilinx_pcie_ops,
> +       };
> +       pci_common_init_dev(dev, &hw);
> +
> +       return 0;
> +}
> +
> +/**
> + * xilinx_pcie_remove - Remove function
> + * @pdev: Platform device pointer
> + *
> + * Return: '0' always
> + */
> +static int xilinx_pcie_remove(struct platform_device *pdev)
> +{
> +       struct xilinx_pcie_port *port = platform_get_drvdata(pdev);
> +
> +       xilinx_pcie_free_irq_domain(port);
> +
> +       return 0;
> +}
> +
> +static struct of_device_id xilinx_pcie_of_match[] = {
> +       { .compatible = "xlnx,axi-pcie-host-1.00.a", },
> +       {}
> +};
> +
> +static struct platform_driver xilinx_pcie_driver = {
> +       .driver = {
> +               .name = "xilinx-pcie",
> +               .owner = THIS_MODULE,
> +               .of_match_table = xilinx_pcie_of_match,
> +               .suppress_bind_attrs = true,
> +       },
> +       .probe = xilinx_pcie_probe,
> +       .remove = xilinx_pcie_remove,
> +};
> +module_platform_driver(xilinx_pcie_driver);
> +
> +MODULE_AUTHOR("Xilinx Inc");
> +MODULE_DESCRIPTION("Xilinx AXI PCIe driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.7.9.5
>



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