// SPDX-License-Identifier: GPL-2.0
/*
* Loongson PCI Host Controller Driver
*
* Copyright (C) 2020 Jiaxun Yang <[email protected]>
*/
#include <linux/of.h>
#include <linux/of_pci.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/pci-acpi.h>
#include <linux/pci-ecam.h>
#include "../pci.h"
/* Device IDs */
#define DEV_LS2K_PCIE_PORT0 0x1a05
#define DEV_LS7A_PCIE_PORT0 0x7a09
#define DEV_LS7A_PCIE_PORT1 0x7a19
#define DEV_LS7A_PCIE_PORT2 0x7a29
#define DEV_LS7A_PCIE_PORT3 0x7a39
#define DEV_LS7A_PCIE_PORT4 0x7a49
#define DEV_LS7A_PCIE_PORT5 0x7a59
#define DEV_LS7A_PCIE_PORT6 0x7a69
#define DEV_LS2K_APB 0x7a02
#define DEV_LS7A_GMAC 0x7a03
#define DEV_LS7A_DC1 0x7a06
#define DEV_LS7A_LPC 0x7a0c
#define DEV_LS7A_AHCI 0x7a08
#define DEV_LS7A_CONF 0x7a10
#define DEV_LS7A_GNET 0x7a13
#define DEV_LS7A_EHCI 0x7a14
#define DEV_LS7A_DC2 0x7a36
#define DEV_LS7A_HDMI 0x7a37
#define FLAG_CFG0 BIT(0)
#define FLAG_CFG1 BIT(1)
#define FLAG_DEV_FIX BIT(2)
#define FLAG_DEV_HIDDEN BIT(3)
struct loongson_pci_data {
u32 flags;
struct pci_ops *ops;
};
struct loongson_pci {
void __iomem *cfg0_base;
void __iomem *cfg1_base;
struct platform_device *pdev;
const struct loongson_pci_data *data;
};
/* Fixup wrong class code in PCIe bridges */
static void bridge_class_quirk(struct pci_dev *dev)
{
dev->class = PCI_CLASS_BRIDGE_PCI_NORMAL;
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT0, bridge_class_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT1, bridge_class_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT2, bridge_class_quirk);
static void system_bus_quirk(struct pci_dev *pdev)
{
/*
* The address space consumed by these devices is outside the
* resources of the host bridge.
*/
pdev->mmio_always_on = 1;
pdev->non_compliant_bars = 1;
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS2K_APB, system_bus_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_CONF, system_bus_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_LPC, system_bus_quirk);
/*
* Some Loongson PCIe ports have hardware limitations on their Maximum Read
* Request Size. They can't handle anything larger than this. Sane
* firmware will set proper MRRS at boot, so we only need no_inc_mrrs for
* bridges. However, some MIPS Loongson firmware doesn't set MRRS properly,
* so we have to enforce maximum safe MRRS, which is 256 bytes.
*/
#ifdef CONFIG_MIPS
static void loongson_set_min_mrrs_quirk(struct pci_dev *pdev)
{
struct pci_bus *bus = pdev->bus;
struct pci_dev *bridge;
static const struct pci_device_id bridge_devids[] = {
{ PCI_VDEVICE(LOONGSON, DEV_LS2K_PCIE_PORT0) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT0) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT1) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT2) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT3) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT4) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT5) },
{ PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT6) },
{ 0, },
};
/* look for the matching bridge */
while (!pci_is_root_bus(bus)) {
bridge = bus->self;
bus = bus->parent;
if (pci_match_id(bridge_devids, bridge)) {
if (pcie_get_readrq(pdev) > 256) {
pci_info(pdev, "limiting MRRS to 256\n");
pcie_set_readrq(pdev, 256);
}
break;
}
}
}
DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, loongson_set_min_mrrs_quirk);
#endif
static void loongson_mrrs_quirk(struct pci_dev *pdev)
{
struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
bridge->no_inc_mrrs = 1;
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS2K_PCIE_PORT0, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT0, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT1, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT2, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT3, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT4, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT5, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_PCIE_PORT6, loongson_mrrs_quirk);
static void loongson_pci_pin_quirk(struct pci_dev *pdev)
{
pdev->pin = 1 + (PCI_FUNC(pdev->devfn) & 3);
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_DC1, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_DC2, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_GMAC, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_AHCI, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_EHCI, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_GNET, loongson_pci_pin_quirk);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_HDMI, loongson_pci_pin_quirk);
static void loongson_pci_msi_quirk(struct pci_dev *dev)
{
u16 val, class = dev->class >> 8;
if (class != PCI_CLASS_BRIDGE_HOST)
return;
pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &val);
val |= PCI_MSI_FLAGS_ENABLE;
pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, val);
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, DEV_LS7A_PCIE_PORT5, loongson_pci_msi_quirk);
static struct loongson_pci *pci_bus_to_loongson_pci(struct pci_bus *bus)
{
struct pci_config_window *cfg;
if (acpi_disabled)
return (struct loongson_pci *)(bus->sysdata);
cfg = bus->sysdata;
return (struct loongson_pci *)(cfg->priv);
}
static void __iomem *cfg0_map(struct loongson_pci *priv, struct pci_bus *bus,
unsigned int devfn, int where)
{
unsigned long addroff = 0x0;
unsigned char busnum = bus->number;
if (!pci_is_root_bus(bus)) {
addroff |= BIT(24); /* Type 1 Access */
addroff |= (busnum << 16);
}
addroff |= (devfn << 8) | where;
return priv->cfg0_base + addroff;
}
static void __iomem *cfg1_map(struct loongson_pci *priv, struct pci_bus *bus,
unsigned int devfn, int where)
{
unsigned long addroff = 0x0;
unsigned char busnum = bus->number;
if (!pci_is_root_bus(bus)) {
addroff |= BIT(28); /* Type 1 Access */
addroff |= (busnum << 16);
}
addroff |= (devfn << 8) | (where & 0xff) | ((where & 0xf00) << 16);
return priv->cfg1_base + addroff;
}
static bool pdev_may_exist(struct pci_bus *bus, unsigned int device,
unsigned int function)
{
return !(pci_is_root_bus(bus) &&
(device >= 9 && device <= 20) && (function > 0));
}
static void __iomem *pci_loongson_map_bus(struct pci_bus *bus,
unsigned int devfn, int where)
{
unsigned int device = PCI_SLOT(devfn);
unsigned int function = PCI_FUNC(devfn);
struct loongson_pci *priv = pci_bus_to_loongson_pci(bus);
/*
* Do not read more than one device on the bus other than
* the host bus.
*/
if ((priv->data->flags & FLAG_DEV_FIX) && bus->self) {
if (!pci_is_root_bus(bus) && (device > 0))
return NULL;
}
/* Don't access non-existent devices */
if (priv->data->flags & FLAG_DEV_HIDDEN) {
if (!pdev_may_exist(bus, device, function))
return NULL;
}
/* CFG0 can only access standard space */
if (where < PCI_CFG_SPACE_SIZE && priv->cfg0_base)
return cfg0_map(priv, bus, devfn, where);
/* CFG1 can access extended space */
if (where < PCI_CFG_SPACE_EXP_SIZE && priv->cfg1_base)
return cfg1_map(priv, bus, devfn, where);
return NULL;
}
#ifdef CONFIG_OF
static int loongson_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
int irq;
u8 val;
irq = of_irq_parse_and_map_pci(dev, slot, pin);
if (irq > 0)
return irq;
/* Care i8259 legacy systems */
pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &val);
/* i8259 only have 15 IRQs */
if (val > 15)
return 0;
return val;
}
/* LS2K/LS7A accept 8/16/32-bit PCI config operations */
static struct pci_ops loongson_pci_ops = {
.map_bus = pci_loongson_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
/* RS780/SR5690 only accept 32-bit PCI config operations */
static struct pci_ops loongson_pci_ops32 = {
.map_bus = pci_loongson_map_bus,
.read = pci_generic_config_read32,
.write = pci_generic_config_write32,
};
static const struct loongson_pci_data ls2k_pci_data = {
.flags = FLAG_CFG1 | FLAG_DEV_FIX | FLAG_DEV_HIDDEN,
.ops = &loongson_pci_ops,
};
static const struct loongson_pci_data ls7a_pci_data = {
.flags = FLAG_CFG1 | FLAG_DEV_FIX | FLAG_DEV_HIDDEN,
.ops = &loongson_pci_ops,
};
static const struct loongson_pci_data rs780e_pci_data = {
.flags = FLAG_CFG0,
.ops = &loongson_pci_ops32,
};
static const struct of_device_id loongson_pci_of_match[] = {
{ .compatible = "loongson,ls2k-pci",
.data = &ls2k_pci_data, },
{ .compatible = "loongson,ls7a-pci",
.data = &ls7a_pci_data, },
{ .compatible = "loongson,rs780e-pci",
.data = &rs780e_pci_data, },
{}
};
static int loongson_pci_probe(struct platform_device *pdev)
{
struct loongson_pci *priv;
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct pci_host_bridge *bridge;
struct resource *regs;
if (!node)
return -ENODEV;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(*priv));
if (!bridge)
return -ENODEV;
priv = pci_host_bridge_priv(bridge);
priv->pdev = pdev;
priv->data = of_device_get_match_data(dev);
if (priv->data->flags & FLAG_CFG0) {
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
dev_err(dev, "missing mem resources for cfg0\n");
else {
priv->cfg0_base = devm_pci_remap_cfg_resource(dev, regs);
if (IS_ERR(priv->cfg0_base))
return PTR_ERR(priv->cfg0_base);
}
}
if (priv->data->flags & FLAG_CFG1) {
regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!regs)
dev_info(dev, "missing mem resource for cfg1\n");
else {
priv->cfg1_base = devm_pci_remap_cfg_resource(dev, regs);
if (IS_ERR(priv->cfg1_base))
priv->cfg1_base = NULL;
}
}
bridge->sysdata = priv;
bridge->ops = priv->data->ops;
bridge->map_irq = loongson_map_irq;
return pci_host_probe(bridge);
}
static struct platform_driver loongson_pci_driver = {
.driver = {
.name = "loongson-pci",
.of_match_table = loongson_pci_of_match,
},
.probe = loongson_pci_probe,
};
builtin_platform_driver(loongson_pci_driver);
#endif
#ifdef CONFIG_ACPI
static int loongson_pci_ecam_init(struct pci_config_window *cfg)
{
struct device *dev = cfg->parent;
struct loongson_pci *priv;
struct loongson_pci_data *data;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
cfg->priv = priv;
data->flags = FLAG_CFG1 | FLAG_DEV_HIDDEN;
priv->data = data;
priv->cfg1_base = cfg->win - (cfg->busr.start << 16);
return 0;
}
const struct pci_ecam_ops loongson_pci_ecam_ops = {
.bus_shift = 16,
.init = loongson_pci_ecam_init,
.pci_ops = {
.map_bus = pci_loongson_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
}
};
#endif
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