// SPDX-License-Identifier: GPL-2.0+
/*
* BRIEF MODULE DESCRIPTION
* PCI init for Ralink RT2880 solution
*
* Copyright 2007 Ralink Inc. (bruce_chang@ralinktech.com.tw)
*
* May 2007 Bruce Chang
* Initial Release
*
* May 2009 Bruce Chang
* support RT2880/RT3883 PCIe
*
* May 2011 Bruce Chang
* support RT6855/MT7620 PCIe
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <mt7621.h>
#include <ralink_regs.h>
#include "../../pci/pci.h"
/* sysctl */
#define MT7621_CHIP_REV_ID 0x0c
#define MT7621_GPIO_MODE 0x60
#define CHIP_REV_MT7621_E2 0x0101
/* MediaTek specific configuration registers */
#define PCIE_FTS_NUM 0x70c
#define PCIE_FTS_NUM_MASK GENMASK(15, 8)
#define PCIE_FTS_NUM_L0(x) (((x) & 0xff) << 8)
/* rt_sysc_membase relative registers */
#define RALINK_CLKCFG1 0x30
#define RALINK_PCIE_CLK_GEN 0x7c
#define RALINK_PCIE_CLK_GEN1 0x80
/* Host-PCI bridge registers */
#define RALINK_PCI_PCICFG_ADDR 0x0000
#define RALINK_PCI_PCIMSK_ADDR 0x000C
#define RALINK_PCI_CONFIG_ADDR 0x0020
#define RALINK_PCI_CONFIG_DATA 0x0024
#define RALINK_PCI_MEMBASE 0x0028
#define RALINK_PCI_IOBASE 0x002C
/* PCICFG virtual bridges */
#define MT7621_BR0_MASK GENMASK(19, 16)
#define MT7621_BR1_MASK GENMASK(23, 20)
#define MT7621_BR2_MASK GENMASK(27, 24)
#define MT7621_BR_ALL_MASK GENMASK(27, 16)
#define MT7621_BR0_SHIFT 16
#define MT7621_BR1_SHIFT 20
#define MT7621_BR2_SHIFT 24
/* PCIe RC control registers */
#define MT7621_PCIE_OFFSET 0x2000
#define MT7621_NEXT_PORT 0x1000
#define RALINK_PCI_BAR0SETUP_ADDR 0x0010
#define RALINK_PCI_IMBASEBAR0_ADDR 0x0018
#define RALINK_PCI_ID 0x0030
#define RALINK_PCI_CLASS 0x0034
#define RALINK_PCI_SUBID 0x0038
#define RALINK_PCI_STATUS 0x0050
/* Some definition values */
#define PCIE_REVISION_ID BIT(0)
#define PCIE_CLASS_CODE (0x60400 << 8)
#define PCIE_BAR_MAP_MAX GENMASK(30, 16)
#define PCIE_BAR_ENABLE BIT(0)
#define PCIE_PORT_INT_EN(x) BIT(20 + (x))
#define PCIE_PORT_CLK_EN(x) BIT(24 + (x))
#define PCIE_PORT_LINKUP BIT(0)
#define PCIE_CLK_GEN_EN BIT(31)
#define PCIE_CLK_GEN_DIS 0
#define PCIE_CLK_GEN1_DIS GENMASK(30, 24)
#define PCIE_CLK_GEN1_EN (BIT(27) | BIT(25))
#define MEMORY_BASE 0x0
#define PERST_MODE_MASK GENMASK(11, 10)
#define PERST_MODE_GPIO BIT(10)
#define PERST_DELAY_US 1000
/**
* struct mt7621_pcie_port - PCIe port information
* @base: I/O mapped register base
* @list: port list
* @pcie: pointer to PCIe host info
* @phy: pointer to PHY control block
* @pcie_rst: pointer to port reset control
* @slot: port slot
* @enabled: indicates if port is enabled
*/
struct mt7621_pcie_port {
void __iomem *base;
struct list_head list;
struct mt7621_pcie *pcie;
struct phy *phy;
struct reset_control *pcie_rst;
u32 slot;
bool enabled;
};
/**
* struct mt7621_pcie - PCIe host information
* @base: IO Mapped Register Base
* @io: IO resource
* @mem: non-prefetchable memory resource
* @busn: bus range
* @offset: IO / Memory offset
* @dev: Pointer to PCIe device
* @ports: pointer to PCIe port information
* @perst: gpio reset
* @rst: pointer to pcie reset
*/
struct mt7621_pcie {
void __iomem *base;
struct device *dev;
struct resource io;
struct resource mem;
struct resource busn;
struct {
resource_size_t mem;
resource_size_t io;
} offset;
struct list_head ports;
struct gpio_desc *perst;
struct reset_control *rst;
};
static inline u32 pcie_read(struct mt7621_pcie *pcie, u32 reg)
{
return readl(pcie->base + reg);
}
static inline void pcie_write(struct mt7621_pcie *pcie, u32 val, u32 reg)
{
writel(val, pcie->base + reg);
}
static inline u32 pcie_port_read(struct mt7621_pcie_port *port, u32 reg)
{
return readl(port->base + reg);
}
static inline void pcie_port_write(struct mt7621_pcie_port *port,
u32 val, u32 reg)
{
writel(val, port->base + reg);
}
static inline u32 mt7621_pci_get_cfgaddr(unsigned int bus, unsigned int slot,
unsigned int func, unsigned int where)
{
return (((where & 0xF00) >> 8) << 24) | (bus << 16) | (slot << 11) |
(func << 8) | (where & 0xfc) | 0x80000000;
}
static void __iomem *mt7621_pcie_map_bus(struct pci_bus *bus,
unsigned int devfn, int where)
{
struct mt7621_pcie *pcie = bus->sysdata;
u32 address = mt7621_pci_get_cfgaddr(bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn), where);
writel(address, pcie->base + RALINK_PCI_CONFIG_ADDR);
return pcie->base + RALINK_PCI_CONFIG_DATA + (where & 3);
}
struct pci_ops mt7621_pci_ops = {
.map_bus = mt7621_pcie_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
static u32 read_config(struct mt7621_pcie *pcie, unsigned int dev, u32 reg)
{
u32 address = mt7621_pci_get_cfgaddr(0, dev, 0, reg);
pcie_write(pcie, address, RALINK_PCI_CONFIG_ADDR);
return pcie_read(pcie, RALINK_PCI_CONFIG_DATA);
}
static void write_config(struct mt7621_pcie *pcie, unsigned int dev,
u32 reg, u32 val)
{
u32 address = mt7621_pci_get_cfgaddr(0, dev, 0, reg);
pcie_write(pcie, address, RALINK_PCI_CONFIG_ADDR);
pcie_write(pcie, val, RALINK_PCI_CONFIG_DATA);
}
static inline void mt7621_perst_gpio_pcie_assert(struct mt7621_pcie *pcie)
{
gpiod_set_value(pcie->perst, 0);
mdelay(PERST_DELAY_US);
}
static inline void mt7621_perst_gpio_pcie_deassert(struct mt7621_pcie *pcie)
{
gpiod_set_value(pcie->perst, 1);
mdelay(PERST_DELAY_US);
}
static inline bool mt7621_pcie_port_is_linkup(struct mt7621_pcie_port *port)
{
return (pcie_port_read(port, RALINK_PCI_STATUS) & PCIE_PORT_LINKUP) != 0;
}
static inline void mt7621_pcie_port_clk_disable(struct mt7621_pcie_port *port)
{
rt_sysc_m32(PCIE_PORT_CLK_EN(port->slot), 0, RALINK_CLKCFG1);
}
static inline void mt7621_control_assert(struct mt7621_pcie_port *port)
{
u32 chip_rev_id = rt_sysc_r32(MT7621_CHIP_REV_ID);
if ((chip_rev_id & 0xFFFF) == CHIP_REV_MT7621_E2)
reset_control_assert(port->pcie_rst);
else
reset_control_deassert(port->pcie_rst);
}
static inline void mt7621_control_deassert(struct mt7621_pcie_port *port)
{
u32 chip_rev_id = rt_sysc_r32(MT7621_CHIP_REV_ID);
if ((chip_rev_id & 0xFFFF) == CHIP_REV_MT7621_E2)
reset_control_deassert(port->pcie_rst);
else
reset_control_assert(port->pcie_rst);
}
static void mt7621_reset_port(struct mt7621_pcie_port *port)
{
mt7621_control_assert(port);
msleep(100);
mt7621_control_deassert(port);
}
static void setup_cm_memory_region(struct mt7621_pcie *pcie)
{
struct resource *mem_resource = &pcie->mem;
struct device *dev = pcie->dev;
resource_size_t mask;
if (mips_cps_numiocu(0)) {
/*
* FIXME: hardware doesn't accept mask values with 1s after
* 0s (e.g. 0xffef), so it would be great to warn if that's
* about to happen
*/
mask = ~(mem_resource->end - mem_resource->start);
write_gcr_reg1_base(mem_resource->start);
write_gcr_reg1_mask(mask | CM_GCR_REGn_MASK_CMTGT_IOCU0);
dev_info(dev, "PCI coherence region base: 0x%08llx, mask/settings: 0x%08llx\n",
(unsigned long long)read_gcr_reg1_base(),
(unsigned long long)read_gcr_reg1_mask());
}
}
static int mt7621_pci_parse_request_of_pci_ranges(struct mt7621_pcie *pcie)
{
struct device *dev = pcie->dev;
struct device_node *node = dev->of_node;
struct of_pci_range_parser parser;
struct of_pci_range range;
int err;
if (of_pci_range_parser_init(&parser, node)) {
dev_err(dev, "missing \"ranges\" property\n");
return -EINVAL;
}
for_each_of_pci_range(&parser, &range) {
struct resource *res = NULL;
switch (range.flags & IORESOURCE_TYPE_BITS) {
case IORESOURCE_IO:
ioremap(range.cpu_addr, range.size);
res = &pcie->io;
pcie->offset.io = 0x00000000UL;
break;
case IORESOURCE_MEM:
res = &pcie->mem;
pcie->offset.mem = 0x00000000UL;
break;
}
if (res)
of_pci_range_to_resource(&range, node, res);
}
err = of_pci_parse_bus_range(node, &pcie->busn);
if (err < 0) {
dev_err(dev, "failed to parse bus ranges property: %d\n", err);
pcie->busn.name = node->name;
pcie->busn.start = 0;
pcie->busn.end = 0xff;
pcie->busn.flags = IORESOURCE_BUS;
}
return 0;
}
static int mt7621_pcie_parse_port(struct mt7621_pcie *pcie,
struct device_node *node,
int slot)
{
struct mt7621_pcie_port *port;
struct device *dev = pcie->dev;
struct device_node *pnode = dev->of_node;
struct resource regs;
char name[10];
int err;
port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
err = of_address_to_resource(pnode, slot + 1, ®s);
if (err) {
dev_err(dev, "missing \"reg\" property\n");
return err;
}
port->base = devm_ioremap_resource(dev, ®s);
if (IS_ERR(port->base))
return PTR_ERR(port->base);
snprintf(name, sizeof(name), "pcie%d", slot);
port->pcie_rst = devm_reset_control_get_exclusive(dev, name);
if (PTR_ERR(port->pcie_rst) == -EPROBE_DEFER) {
dev_err(dev, "failed to get pcie%d reset control\n", slot);
return PTR_ERR(port->pcie_rst);
}
snprintf(name, sizeof(name), "pcie-phy%d", slot);
port->phy = devm_phy_get(dev, name);
if (IS_ERR(port->phy))
return PTR_ERR(port->phy);
port->slot = slot;
port->pcie = pcie;
INIT_LIST_HEAD(&port->list);
list_add_tail(&port->list, &pcie->ports);
return 0;
}
static int mt7621_pcie_parse_dt(struct mt7621_pcie *pcie)
{
struct device *dev = pcie->dev;
struct device_node *node = dev->of_node, *child;
struct resource regs;
int err;
pcie->perst = devm_gpiod_get(dev, "perst", GPIOD_OUT_HIGH);
if (IS_ERR(pcie->perst)) {
dev_err(dev, "failed to get gpio perst\n");
return PTR_ERR(pcie->perst);
}
err = of_address_to_resource(node, 0, ®s);
if (err) {
dev_err(dev, "missing \"reg\" property\n");
return err;
}
pcie->base = devm_ioremap_resource(dev, ®s);
if (IS_ERR(pcie->base))
return PTR_ERR(pcie->base);
pcie->rst = devm_reset_control_get_exclusive(dev, "pcie");
if (PTR_ERR(pcie->rst) == -EPROBE_DEFER) {
dev_err(dev, "failed to get pcie reset control\n");
return PTR_ERR(pcie->rst);
}
for_each_available_child_of_node(node, child) {
int slot;
err = of_pci_get_devfn(child);
if (err < 0) {
of_node_put(child);
dev_err(dev, "failed to parse devfn: %d\n", err);
return err;
}
slot = PCI_SLOT(err);
err = mt7621_pcie_parse_port(pcie, child, slot);
if (err) {
of_node_put(child);
return err;
}
}
return 0;
}
static int mt7621_pcie_init_port(struct mt7621_pcie_port *port)
{
struct mt7621_pcie *pcie = port->pcie;
struct device *dev = pcie->dev;
u32 slot = port->slot;
int err;
/*
* Any MT7621 Ralink pcie controller that doesn't have 0x0101 at
* the end of the chip_id has inverted PCI resets.
*/
mt7621_reset_port(port);
err = phy_init(port->phy);
if (err) {
dev_err(dev, "failed to initialize port%d phy\n", slot);
return err;
}
err = phy_power_on(port->phy);
if (err) {
dev_err(dev, "failed to power on port%d phy\n", slot);
phy_exit(port->phy);
return err;
}
port->enabled = true;
return 0;
}
static void mt7621_pcie_init_ports(struct mt7621_pcie *pcie)
{
struct device *dev = pcie->dev;
struct mt7621_pcie_port *port, *tmp;
u32 val = 0;
int err;
rt_sysc_m32(PERST_MODE_MASK, PERST_MODE_GPIO, MT7621_GPIO_MODE);
mt7621_perst_gpio_pcie_assert(pcie);
list_for_each_entry_safe(port, tmp, &pcie->ports, list) {
u32 slot = port->slot;
err = mt7621_pcie_init_port(port);
if (err) {
dev_err(dev, "Initiating port %d failed\n", slot);
list_del(&port->list);
} else {
val = read_config(pcie, slot, PCIE_FTS_NUM);
dev_info(dev, "Port %d N_FTS = %x\n", slot,
(unsigned int)val);
}
}
reset_control_assert(pcie->rst);
mt7621_perst_gpio_pcie_deassert(pcie);
list_for_each_entry(port, &pcie->ports, list) {
u32 slot = port->slot;
if (!mt7621_pcie_port_is_linkup(port)) {
dev_err(dev, "pcie%d no card, disable it (RST & CLK)\n",
slot);
phy_power_off(port->phy);
mt7621_control_assert(port);
mt7621_pcie_port_clk_disable(port);
port->enabled = false;
}
}
rt_sysc_m32(0x30, 2 << 4, SYSC_REG_SYSTEM_CONFIG1);
rt_sysc_m32(PCIE_CLK_GEN_EN, PCIE_CLK_GEN_DIS, RALINK_PCIE_CLK_GEN);
rt_sysc_m32(PCIE_CLK_GEN1_DIS, PCIE_CLK_GEN1_EN, RALINK_PCIE_CLK_GEN1);
rt_sysc_m32(PCIE_CLK_GEN_DIS, PCIE_CLK_GEN_EN, RALINK_PCIE_CLK_GEN);
msleep(50);
reset_control_deassert(pcie->rst);
}
static void mt7621_pcie_enable_port(struct mt7621_pcie_port *port)
{
struct mt7621_pcie *pcie = port->pcie;
u32 slot = port->slot;
u32 offset = MT7621_PCIE_OFFSET + (slot * MT7621_NEXT_PORT);
u32 val;
/* enable pcie interrupt */
val = pcie_read(pcie, RALINK_PCI_PCIMSK_ADDR);
val |= PCIE_PORT_INT_EN(slot);
pcie_write(pcie, val, RALINK_PCI_PCIMSK_ADDR);
/* map 2G DDR region */
pcie_write(pcie, PCIE_BAR_MAP_MAX | PCIE_BAR_ENABLE,
offset + RALINK_PCI_BAR0SETUP_ADDR);
pcie_write(pcie, MEMORY_BASE,
offset + RALINK_PCI_IMBASEBAR0_ADDR);
/* configure class code and revision ID */
pcie_write(pcie, PCIE_CLASS_CODE | PCIE_REVISION_ID,
offset + RALINK_PCI_CLASS);
}
static void mt7621_pcie_enable_ports(struct mt7621_pcie *pcie)
{
struct device *dev = pcie->dev;
struct mt7621_pcie_port *port;
u8 num_slots_enabled = 0;
u32 slot;
u32 val;
list_for_each_entry(port, &pcie->ports, list) {
if (port->enabled) {
mt7621_pcie_enable_port(port);
dev_info(dev, "PCIE%d enabled\n", num_slots_enabled);
num_slots_enabled++;
}
}
for (slot = 0; slot < num_slots_enabled; slot++) {
val = read_config(pcie, slot, PCI_COMMAND);
val |= PCI_COMMAND_MASTER;
write_config(pcie, slot, PCI_COMMAND, val);
/* configure RC FTS number to 250 when it leaves L0s */
val = read_config(pcie, slot, PCIE_FTS_NUM);
val &= ~PCIE_FTS_NUM_MASK;
val |= PCIE_FTS_NUM_L0(0x50);
write_config(pcie, slot, PCIE_FTS_NUM, val);
}
}
static int mt7621_pcie_init_virtual_bridges(struct mt7621_pcie *pcie)
{
u32 pcie_link_status = 0;
u32 val = 0;
struct mt7621_pcie_port *port;
list_for_each_entry(port, &pcie->ports, list) {
u32 slot = port->slot;
if (port->enabled)
pcie_link_status |= BIT(slot);
}
if (pcie_link_status == 0)
return -1;
/*
* pcie(2/1/0) link status pcie2_num pcie1_num pcie0_num
* 3'b000 x x x
* 3'b001 x x 0
* 3'b010 x 0 x
* 3'b011 x 1 0
* 3'b100 0 x x
* 3'b101 1 x 0
* 3'b110 1 0 x
* 3'b111 2 1 0
*/
switch (pcie_link_status) {
case 2:
val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
val &= ~(MT7621_BR0_MASK | MT7621_BR1_MASK);
val |= 0x1 << MT7621_BR0_SHIFT;
val |= 0x0 << MT7621_BR1_SHIFT;
pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
break;
case 4:
val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
val &= ~MT7621_BR_ALL_MASK;
val |= 0x1 << MT7621_BR0_SHIFT;
val |= 0x2 << MT7621_BR1_SHIFT;
val |= 0x0 << MT7621_BR2_SHIFT;
pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
break;
case 5:
val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
val &= ~MT7621_BR_ALL_MASK;
val |= 0x0 << MT7621_BR0_SHIFT;
val |= 0x2 << MT7621_BR1_SHIFT;
val |= 0x1 << MT7621_BR2_SHIFT;
pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
break;
case 6:
val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
val &= ~MT7621_BR_ALL_MASK;
val |= 0x2 << MT7621_BR0_SHIFT;
val |= 0x0 << MT7621_BR1_SHIFT;
val |= 0x1 << MT7621_BR2_SHIFT;
pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
break;
}
return 0;
}
static int mt7621_pcie_request_resources(struct mt7621_pcie *pcie,
struct list_head *res)
{
struct device *dev = pcie->dev;
pci_add_resource_offset(res, &pcie->io, pcie->offset.io);
pci_add_resource_offset(res, &pcie->mem, pcie->offset.mem);
pci_add_resource(res, &pcie->busn);
return devm_request_pci_bus_resources(dev, res);
}
static int mt7621_pcie_register_host(struct pci_host_bridge *host,
struct list_head *res)
{
struct mt7621_pcie *pcie = pci_host_bridge_priv(host);
list_splice_init(res, &host->windows);
host->busnr = pcie->busn.start;
host->dev.parent = pcie->dev;
host->ops = &mt7621_pci_ops;
host->map_irq = of_irq_parse_and_map_pci;
host->swizzle_irq = pci_common_swizzle;
host->sysdata = pcie;
return pci_host_probe(host);
}
static int mt7621_pci_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mt7621_pcie *pcie;
struct pci_host_bridge *bridge;
int err;
LIST_HEAD(res);
if (!dev->of_node)
return -ENODEV;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
if (!bridge)
return -ENOMEM;
pcie = pci_host_bridge_priv(bridge);
pcie->dev = dev;
platform_set_drvdata(pdev, pcie);
INIT_LIST_HEAD(&pcie->ports);
err = mt7621_pcie_parse_dt(pcie);
if (err) {
dev_err(dev, "Parsing DT failed\n");
return err;
}
/* set resources limits */
iomem_resource.start = 0;
iomem_resource.end = ~0UL; /* no limit */
ioport_resource.start = 0;
ioport_resource.end = ~0UL; /* no limit */
mt7621_pcie_init_ports(pcie);
err = mt7621_pcie_init_virtual_bridges(pcie);
if (err) {
dev_err(dev, "Nothing is connected in virtual bridges. Exiting...");
return 0;
}
mt7621_pcie_enable_ports(pcie);
err = mt7621_pci_parse_request_of_pci_ranges(pcie);
if (err) {
dev_err(dev, "Error requesting pci resources from ranges");
return err;
}
setup_cm_memory_region(pcie);
err = mt7621_pcie_request_resources(pcie, &res);
if (err) {
dev_err(dev, "Error requesting resources\n");
return err;
}
err = mt7621_pcie_register_host(bridge, &res);
if (err) {
dev_err(dev, "Error registering host\n");
return err;
}
return 0;
}
static const struct of_device_id mt7621_pci_ids[] = {
{ .compatible = "mediatek,mt7621-pci" },
{},
};
MODULE_DEVICE_TABLE(of, mt7621_pci_ids);
static struct platform_driver mt7621_pci_driver = {
.probe = mt7621_pci_probe,
.driver = {
.name = "mt7621-pci",
.of_match_table = of_match_ptr(mt7621_pci_ids),
},
};
static int __init mt7621_pci_init(void)
{
return platform_driver_register(&mt7621_pci_driver);
}
module_init(mt7621_pci_init);