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

From: Srikanth Thokala
Date: Wed Aug 20 2014 - 12:26:28 EST

This is the driver for Xilinx AXI PCIe Host Bridge Soft IP

Signed-off-by: Srikanth Thokala <sthokal@xxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
---
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@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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