// SPDX-License-Identifier: GPL-2.0+
/*
* PCIe host controller driver for Xilinx Versal CPM DMA Bridge
*
* (C) Copyright 2019 - 2020, Xilinx, Inc.
*/
#include <linux/bitfield.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include "../pci.h"
#include "pcie-xilinx-common.h"
/* Register definitions */
#define XILINX_CPM_PCIE_REG_IDR 0x00000E10
#define XILINX_CPM_PCIE_REG_IMR 0x00000E14
#define XILINX_CPM_PCIE_REG_PSCR 0x00000E1C
#define XILINX_CPM_PCIE_REG_RPSC 0x00000E20
#define XILINX_CPM_PCIE_REG_RPEFR 0x00000E2C
#define XILINX_CPM_PCIE_REG_IDRN 0x00000E38
#define XILINX_CPM_PCIE_REG_IDRN_MASK 0x00000E3C
#define XILINX_CPM_PCIE_MISC_IR_STATUS 0x00000340
#define XILINX_CPM_PCIE_MISC_IR_ENABLE 0x00000348
#define XILINX_CPM_PCIE_MISC_IR_LOCAL BIT(1)
#define XILINX_CPM_PCIE_IR_STATUS 0x000002A0
#define XILINX_CPM_PCIE_IR_ENABLE 0x000002A8
#define XILINX_CPM_PCIE_IR_LOCAL BIT(0)
#define IMR(x) BIT(XILINX_PCIE_INTR_ ##x)
#define XILINX_CPM_PCIE_IMR_ALL_MASK \
( \
IMR(LINK_DOWN) | \
IMR(HOT_RESET) | \
IMR(CFG_PCIE_TIMEOUT) | \
IMR(CFG_TIMEOUT) | \
IMR(CORRECTABLE) | \
IMR(NONFATAL) | \
IMR(FATAL) | \
IMR(CFG_ERR_POISON) | \
IMR(PME_TO_ACK_RCVD) | \
IMR(INTX) | \
IMR(PM_PME_RCVD) | \
IMR(SLV_UNSUPP) | \
IMR(SLV_UNEXP) | \
IMR(SLV_COMPL) | \
IMR(SLV_ERRP) | \
IMR(SLV_CMPABT) | \
IMR(SLV_ILLBUR) | \
IMR(MST_DECERR) | \
IMR(MST_SLVERR) | \
IMR(SLV_PCIE_TIMEOUT) \
)
#define XILINX_CPM_PCIE_IDR_ALL_MASK 0xFFFFFFFF
#define XILINX_CPM_PCIE_IDRN_MASK GENMASK(19, 16)
#define XILINX_CPM_PCIE_IDRN_SHIFT 16
/* Root Port Error FIFO Read Register definitions */
#define XILINX_CPM_PCIE_RPEFR_ERR_VALID BIT(18)
#define XILINX_CPM_PCIE_RPEFR_REQ_ID GENMASK(15, 0)
#define XILINX_CPM_PCIE_RPEFR_ALL_MASK 0xFFFFFFFF
/* Root Port Status/control Register definitions */
#define XILINX_CPM_PCIE_REG_RPSC_BEN BIT(0)
/* Phy Status/Control Register definitions */
#define XILINX_CPM_PCIE_REG_PSCR_LNKUP BIT(11)
enum xilinx_cpm_version {
CPM,
CPM5,
};
/**
* struct xilinx_cpm_variant - CPM variant information
* @version: CPM version
*/
struct xilinx_cpm_variant {
enum xilinx_cpm_version version;
};
/**
* struct xilinx_cpm_pcie - PCIe port information
* @dev: Device pointer
* @reg_base: Bridge Register Base
* @cpm_base: CPM System Level Control and Status Register(SLCR) Base
* @intx_domain: Legacy IRQ domain pointer
* @cpm_domain: CPM IRQ domain pointer
* @cfg: Holds mappings of config space window
* @intx_irq: legacy interrupt number
* @irq: Error interrupt number
* @lock: lock protecting shared register access
* @variant: CPM version check pointer
*/
struct xilinx_cpm_pcie {
struct device *dev;
void __iomem *reg_base;
void __iomem *cpm_base;
struct irq_domain *intx_domain;
struct irq_domain *cpm_domain;
struct pci_config_window *cfg;
int intx_irq;
int irq;
raw_spinlock_t lock;
const struct xilinx_cpm_variant *variant;
};
static u32 pcie_read(struct xilinx_cpm_pcie *port, u32 reg)
{
return readl_relaxed(port->reg_base + reg);
}
static void pcie_write(struct xilinx_cpm_pcie *port,
u32 val, u32 reg)
{
writel_relaxed(val, port->reg_base + reg);
}
static bool cpm_pcie_link_up(struct xilinx_cpm_pcie *port)
{
return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
XILINX_CPM_PCIE_REG_PSCR_LNKUP);
}
static void cpm_pcie_clear_err_interrupts(struct xilinx_cpm_pcie *port)
{
unsigned long val = pcie_read(port, XILINX_CPM_PCIE_REG_RPEFR);
if (val & XILINX_CPM_PCIE_RPEFR_ERR_VALID) {
dev_dbg(port->dev, "Requester ID %lu\n",
val & XILINX_CPM_PCIE_RPEFR_REQ_ID);
pcie_write(port, XILINX_CPM_PCIE_RPEFR_ALL_MASK,
XILINX_CPM_PCIE_REG_RPEFR);
}
}
static void xilinx_cpm_mask_leg_irq(struct irq_data *data)
{
struct xilinx_cpm_pcie *port = irq_data_get_irq_chip_data(data);
unsigned long flags;
u32 mask;
u32 val;
mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
raw_spin_lock_irqsave(&port->lock, flags);
val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
pcie_write(port, (val & (~mask)), XILINX_CPM_PCIE_REG_IDRN_MASK);
raw_spin_unlock_irqrestore(&port->lock, flags);
}
static void xilinx_cpm_unmask_leg_irq(struct irq_data *data)
{
struct xilinx_cpm_pcie *port = irq_data_get_irq_chip_data(data);
unsigned long flags;
u32 mask;
u32 val;
mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
raw_spin_lock_irqsave(&port->lock, flags);
val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
pcie_write(port, (val | mask), XILINX_CPM_PCIE_REG_IDRN_MASK);
raw_spin_unlock_irqrestore(&port->lock, flags);
}
static struct irq_chip xilinx_cpm_leg_irq_chip = {
.name = "INTx",
.irq_mask = xilinx_cpm_mask_leg_irq,
.irq_unmask = xilinx_cpm_unmask_leg_irq,
};
/**
* xilinx_cpm_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_cpm_pcie_intx_map(struct irq_domain *domain,
unsigned int irq, irq_hw_number_t hwirq)
{
irq_set_chip_and_handler(irq, &xilinx_cpm_leg_irq_chip,
handle_level_irq);
irq_set_chip_data(irq, domain->host_data);
irq_set_status_flags(irq, IRQ_LEVEL);
return 0;
}
/* INTx IRQ Domain operations */
static const struct irq_domain_ops intx_domain_ops = {
.map = xilinx_cpm_pcie_intx_map,
};
static void xilinx_cpm_pcie_intx_flow(struct irq_desc *desc)
{
struct xilinx_cpm_pcie *port = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned long val;
int i;
chained_irq_enter(chip, desc);
val = FIELD_GET(XILINX_CPM_PCIE_IDRN_MASK,
pcie_read(port, XILINX_CPM_PCIE_REG_IDRN));
for_each_set_bit(i, &val, PCI_NUM_INTX)
generic_handle_domain_irq(port->intx_domain, i);
chained_irq_exit(chip, desc);
}
static void xilinx_cpm_mask_event_irq(struct irq_data *d)
{
struct xilinx_cpm_pcie *port = irq_data_get_irq_chip_data(d);
u32 val;
raw_spin_lock(&port->lock);
val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
val &= ~BIT(d->hwirq);
pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
raw_spin_unlock(&port->lock);
}
static void xilinx_cpm_unmask_event_irq(struct irq_data *d)
{
struct xilinx_cpm_pcie *port = irq_data_get_irq_chip_data(d);
u32 val;
raw_spin_lock(&port->lock);
val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
val |= BIT(d->hwirq);
pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
raw_spin_unlock(&port->lock);
}
static struct irq_chip xilinx_cpm_event_irq_chip = {
.name = "RC-Event",
.irq_mask = xilinx_cpm_mask_event_irq,
.irq_unmask = xilinx_cpm_unmask_event_irq,
};
static int xilinx_cpm_pcie_event_map(struct irq_domain *domain,
unsigned int irq, irq_hw_number_t hwirq)
{
irq_set_chip_and_handler(irq, &xilinx_cpm_event_irq_chip,
handle_level_irq);
irq_set_chip_data(irq, domain->host_data);
irq_set_status_flags(irq, IRQ_LEVEL);
return 0;
}
static const struct irq_domain_ops event_domain_ops = {
.map = xilinx_cpm_pcie_event_map,
};
static void xilinx_cpm_pcie_event_flow(struct irq_desc *desc)
{
struct xilinx_cpm_pcie *port = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned long val;
int i;
chained_irq_enter(chip, desc);
val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
val &= pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
for_each_set_bit(i, &val, 32)
generic_handle_domain_irq(port->cpm_domain, i);
pcie_write(port, val, XILINX_CPM_PCIE_REG_IDR);
if (port->variant->version == CPM5) {
val = readl_relaxed(port->cpm_base + XILINX_CPM_PCIE_IR_STATUS);
if (val)
writel_relaxed(val, port->cpm_base +
XILINX_CPM_PCIE_IR_STATUS);
}
/*
* XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
* CPM SLCR block.
*/
val = readl_relaxed(port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
if (val)
writel_relaxed(val,
port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
chained_irq_exit(chip, desc);
}
#define _IC(x, s) \
[XILINX_PCIE_INTR_ ## x] = { __stringify(x), s }
static const struct {
const char *sym;
const char *str;
} intr_cause[32] = {
_IC(LINK_DOWN, "Link Down"),
_IC(HOT_RESET, "Hot reset"),
_IC(CFG_TIMEOUT, "ECAM access timeout"),
_IC(CORRECTABLE, "Correctable error message"),
_IC(NONFATAL, "Non fatal error message"),
_IC(FATAL, "Fatal error message"),
_IC(SLV_UNSUPP, "Slave unsupported request"),
_IC(SLV_UNEXP, "Slave unexpected completion"),
_IC(SLV_COMPL, "Slave completion timeout"),
_IC(SLV_ERRP, "Slave Error Poison"),
_IC(SLV_CMPABT, "Slave Completer Abort"),
_IC(SLV_ILLBUR, "Slave Illegal Burst"),
_IC(MST_DECERR, "Master decode error"),
_IC(MST_SLVERR, "Master slave error"),
_IC(CFG_PCIE_TIMEOUT, "PCIe ECAM access timeout"),
_IC(CFG_ERR_POISON, "ECAM poisoned completion received"),
_IC(PME_TO_ACK_RCVD, "PME_TO_ACK message received"),
_IC(PM_PME_RCVD, "PM_PME message received"),
_IC(SLV_PCIE_TIMEOUT, "PCIe completion timeout received"),
};
static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *dev_id)
{
struct xilinx_cpm_pcie *port = dev_id;
struct device *dev = port->dev;
struct irq_data *d;
d = irq_domain_get_irq_data(port->cpm_domain, irq);
switch (d->hwirq) {
case XILINX_PCIE_INTR_CORRECTABLE:
case XILINX_PCIE_INTR_NONFATAL:
case XILINX_PCIE_INTR_FATAL:
cpm_pcie_clear_err_interrupts(port);
fallthrough;
default:
if (intr_cause[d->hwirq].str)
dev_warn(dev, "%s\n", intr_cause[d->hwirq].str);
else
dev_warn(dev, "Unknown IRQ %ld\n", d->hwirq);
}
return IRQ_HANDLED;
}
static void xilinx_cpm_free_irq_domains(struct xilinx_cpm_pcie *port)
{
if (port->intx_domain) {
irq_domain_remove(port->intx_domain);
port->intx_domain = NULL;
}
if (port->cpm_domain) {
irq_domain_remove(port->cpm_domain);
port->cpm_domain = NULL;
}
}
/**
* xilinx_cpm_pcie_init_irq_domain - Initialize IRQ domain
* @port: PCIe port information
*
* Return: '0' on success and error value on failure
*/
static int xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie *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 -EINVAL;
}
port->cpm_domain = irq_domain_add_linear(pcie_intc_node, 32,
&event_domain_ops,
port);
if (!port->cpm_domain)
goto out;
irq_domain_update_bus_token(port->cpm_domain, DOMAIN_BUS_NEXUS);
port->intx_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
&intx_domain_ops,
port);
if (!port->intx_domain)
goto out;
irq_domain_update_bus_token(port->intx_domain, DOMAIN_BUS_WIRED);
of_node_put(pcie_intc_node);
raw_spin_lock_init(&port->lock);
return 0;
out:
xilinx_cpm_free_irq_domains(port);
of_node_put(pcie_intc_node);
dev_err(dev, "Failed to allocate IRQ domains\n");
return -ENOMEM;
}
static int xilinx_cpm_setup_irq(struct xilinx_cpm_pcie *port)
{
struct device *dev = port->dev;
struct platform_device *pdev = to_platform_device(dev);
int i, irq;
port->irq = platform_get_irq(pdev, 0);
if (port->irq < 0)
return port->irq;
for (i = 0; i < ARRAY_SIZE(intr_cause); i++) {
int err;
if (!intr_cause[i].str)
continue;
irq = irq_create_mapping(port->cpm_domain, i);
if (!irq) {
dev_err(dev, "Failed to map interrupt\n");
return -ENXIO;
}
err = devm_request_irq(dev, irq, xilinx_cpm_pcie_intr_handler,
0, intr_cause[i].sym, port);
if (err) {
dev_err(dev, "Failed to request IRQ %d\n", irq);
return err;
}
}
port->intx_irq = irq_create_mapping(port->cpm_domain,
XILINX_PCIE_INTR_INTX);
if (!port->intx_irq) {
dev_err(dev, "Failed to map INTx interrupt\n");
return -ENXIO;
}
/* Plug the INTx chained handler */
irq_set_chained_handler_and_data(port->intx_irq,
xilinx_cpm_pcie_intx_flow, port);
/* Plug the main event chained handler */
irq_set_chained_handler_and_data(port->irq,
xilinx_cpm_pcie_event_flow, port);
return 0;
}
/**
* xilinx_cpm_pcie_init_port - Initialize hardware
* @port: PCIe port information
*/
static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie *port)
{
if (cpm_pcie_link_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_CPM_PCIE_IDR_ALL_MASK,
XILINX_CPM_PCIE_REG_IMR);
/* Clear pending interrupts */
pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_IDR) &
XILINX_CPM_PCIE_IMR_ALL_MASK,
XILINX_CPM_PCIE_REG_IDR);
/*
* XILINX_CPM_PCIE_MISC_IR_ENABLE register is mapped to
* CPM SLCR block.
*/
writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
if (port->variant->version == CPM5) {
writel(XILINX_CPM_PCIE_IR_LOCAL,
port->cpm_base + XILINX_CPM_PCIE_IR_ENABLE);
}
/* Enable the Bridge enable bit */
pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
XILINX_CPM_PCIE_REG_RPSC_BEN,
XILINX_CPM_PCIE_REG_RPSC);
}
/**
* xilinx_cpm_pcie_parse_dt - Parse Device tree
* @port: PCIe port information
* @bus_range: Bus resource
*
* Return: '0' on success and error value on failure
*/
static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie *port,
struct resource *bus_range)
{
struct device *dev = port->dev;
struct platform_device *pdev = to_platform_device(dev);
struct resource *res;
port->cpm_base = devm_platform_ioremap_resource_byname(pdev,
"cpm_slcr");
if (IS_ERR(port->cpm_base))
return PTR_ERR(port->cpm_base);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
if (!res)
return -ENXIO;
port->cfg = pci_ecam_create(dev, res, bus_range,
&pci_generic_ecam_ops);
if (IS_ERR(port->cfg))
return PTR_ERR(port->cfg);
if (port->variant->version == CPM5) {
port->reg_base = devm_platform_ioremap_resource_byname(pdev,
"cpm_csr");
if (IS_ERR(port->reg_base))
return PTR_ERR(port->reg_base);
} else {
port->reg_base = port->cfg->win;
}
return 0;
}
static void xilinx_cpm_free_interrupts(struct xilinx_cpm_pcie *port)
{
irq_set_chained_handler_and_data(port->intx_irq, NULL, NULL);
irq_set_chained_handler_and_data(port->irq, NULL, NULL);
}
/**
* xilinx_cpm_pcie_probe - Probe function
* @pdev: Platform device pointer
*
* Return: '0' on success and error value on failure
*/
static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
{
struct xilinx_cpm_pcie *port;
struct device *dev = &pdev->dev;
struct pci_host_bridge *bridge;
struct resource_entry *bus;
int err;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
if (!bridge)
return -ENODEV;
port = pci_host_bridge_priv(bridge);
port->dev = dev;
err = xilinx_cpm_pcie_init_irq_domain(port);
if (err)
return err;
bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
if (!bus)
return -ENODEV;
port->variant = of_device_get_match_data(dev);
err = xilinx_cpm_pcie_parse_dt(port, bus->res);
if (err) {
dev_err(dev, "Parsing DT failed\n");
goto err_parse_dt;
}
xilinx_cpm_pcie_init_port(port);
err = xilinx_cpm_setup_irq(port);
if (err) {
dev_err(dev, "Failed to set up interrupts\n");
goto err_setup_irq;
}
bridge->sysdata = port->cfg;
bridge->ops = (struct pci_ops *)&pci_generic_ecam_ops.pci_ops;
err = pci_host_probe(bridge);
if (err < 0)
goto err_host_bridge;
return 0;
err_host_bridge:
xilinx_cpm_free_interrupts(port);
err_setup_irq:
pci_ecam_free(port->cfg);
err_parse_dt:
xilinx_cpm_free_irq_domains(port);
return err;
}
static const struct xilinx_cpm_variant cpm_host = {
.version = CPM,
};
static const struct xilinx_cpm_variant cpm5_host = {
.version = CPM5,
};
static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
{
.compatible = "xlnx,versal-cpm-host-1.00",
.data = &cpm_host,
},
{
.compatible = "xlnx,versal-cpm5-host",
.data = &cpm5_host,
},
{}
};
static struct platform_driver xilinx_cpm_pcie_driver = {
.driver = {
.name = "xilinx-cpm-pcie",
.of_match_table = xilinx_cpm_pcie_of_match,
.suppress_bind_attrs = true,
},
.probe = xilinx_cpm_pcie_probe,
};
builtin_platform_driver(xilinx_cpm_pcie_driver);
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