linux_dsm_epyc7002/drivers/pci/host/pcie-xilinx.c
Grygorii Strashko 8ff0ef996c PCI: host: Mark PCIe/PCI (MSI) IRQ cascade handlers as IRQF_NO_THREAD
On -RT and if kernel is booting with "threadirqs" cmd line parameter,
PCIe/PCI (MSI) IRQ cascade handlers (like dra7xx_pcie_msi_irq_handler())
will be forced threaded and, as result, will generate warnings like this:

  WARNING: CPU: 1 PID: 82 at kernel/irq/handle.c:150 handle_irq_event_percpu+0x14c/0x174()
  irq 460 handler irq_default_primary_handler+0x0/0x14 enabled interrupts
  Backtrace:
   (warn_slowpath_common) from (warn_slowpath_fmt+0x38/0x40)
   (warn_slowpath_fmt) from (handle_irq_event_percpu+0x14c/0x174)
   (handle_irq_event_percpu) from (handle_irq_event+0x84/0xb8)
   (handle_irq_event) from (handle_simple_irq+0x90/0x118)
   (handle_simple_irq) from (generic_handle_irq+0x30/0x44)
   (generic_handle_irq) from (dra7xx_pcie_msi_irq_handler+0x7c/0x8c)
   (dra7xx_pcie_msi_irq_handler) from (irq_forced_thread_fn+0x28/0x5c)
   (irq_forced_thread_fn) from (irq_thread+0x128/0x204)

This happens because all of them invoke generic_handle_irq() from the
requested handler.  generic_handle_irq() grabs raw_locks and thus needs to
run in raw-IRQ context.

This issue was originally reproduced on TI dra7-evem, but, as was
identified during discussion [1], other hosts can also suffer from this
issue.  Fix all them at once by marking PCIe/PCI (MSI) IRQ cascade handlers
IRQF_NO_THREAD explicitly.

[1] http://lkml.kernel.org/r/1448027966-21610-1-git-send-email-grygorii.strashko@ti.com

[bhelgaas: add stable tag, fix typos]
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lucas Stach <l.stach@pengutronix.de> (for imx6)
CC: stable@vger.kernel.org
CC: Kishon Vijay Abraham I <kishon@ti.com>
CC: Jingoo Han <jingoohan1@gmail.com>
CC: Kukjin Kim <kgene@kernel.org>
CC: Krzysztof Kozlowski <k.kozlowski@samsung.com>
CC: Richard Zhu <Richard.Zhu@freescale.com>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: Simon Horman <horms@verge.net.au>
CC: Pratyush Anand <pratyush.anand@gmail.com>
CC: Michal Simek <michal.simek@xilinx.com>
CC: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
CC: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2016-01-06 16:08:02 -06:00

896 lines
22 KiB
C

/*
* 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)
{
unsigned long val = pcie_read(port, XILINX_PCIE_REG_RPEFR);
if (val & XILINX_PCIE_RPEFR_ERR_VALID) {
dev_dbg(port->dev, "Requester ID %lu\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_map_bus - 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_map_bus(struct pci_bus *bus,
unsigned int devfn, int where)
{
struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
int relbus;
if (!xilinx_pcie_valid_device(bus, devfn))
return NULL;
relbus = (bus->number << ECAM_BUS_NUM_SHIFT) |
(devfn << ECAM_DEV_NUM_SHIFT);
return port->reg_base + relbus + where;
}
/* PCIe operations */
static struct pci_ops xilinx_pcie_ops = {
.map_bus = xilinx_pcie_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
/* MSI functions */
/**
* xilinx_pcie_destroy_msi - Free MSI number
* @irq: IRQ to be freed
*/
static void xilinx_pcie_destroy_msi(unsigned int irq)
{
struct msi_desc *msi;
struct xilinx_pcie_port *port;
if (!test_bit(irq, msi_irq_in_use)) {
msi = irq_get_msi_desc(irq);
port = sys_to_pcie(msi_desc_to_pci_sysdata(msi));
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_controller *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_controller *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 (hwirq < 0)
return hwirq;
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;
pci_write_msi_msg(irq, &msg);
return 0;
}
/* MSI Chip Descriptor */
static struct msi_controller 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 = pci_msi_unmask_irq,
.irq_disable = pci_msi_mask_irq,
.irq_mask = pci_msi_mask_irq,
.irq_unmask = pci_msi_unmask_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);
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);
}
/* 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);
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;
}
if (!(val & XILINX_PCIE_RPIFR1_MSI_INTR)) {
/* 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;
if (IS_ENABLED(CONFIG_PCI_MSI))
bus = pci_scan_root_bus_msi(port->dev, sys->busnr,
&xilinx_pcie_ops, sys,
&sys->resources,
&xilinx_pcie_msi_chip);
else
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 resource_entry *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);
resource_list_for_each_entry(win, &port->resources)
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 | IRQF_NO_THREAD,
"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,
.scan = xilinx_pcie_scan_bus,
.ops = &xilinx_pcie_ops,
};
#ifdef CONFIG_PCI_MSI
xilinx_pcie_msi_chip.dev = port->dev;
#endif
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",
.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");