diff options
Diffstat (limited to 'drivers/pci/controller/pcie-mt7621.c')
| -rw-r--r-- | drivers/pci/controller/pcie-mt7621.c | 552 |
1 files changed, 552 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-mt7621.c b/drivers/pci/controller/pcie-mt7621.c new file mode 100644 index 0000000000..79e225edb4 --- /dev/null +++ b/drivers/pci/controller/pcie-mt7621.c @@ -0,0 +1,552 @@ +// 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/clk.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.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 <linux/sys_soc.h> + +#include "../pci.h" + +/* 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) + +/* 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 + +/* PCIe RC control registers */ +#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_LINKUP BIT(0) +#define PCIE_PORT_CNT 3 + +#define INIT_PORTS_DELAY_MS 100 +#define PERST_DELAY_MS 100 + +/** + * struct mt7621_pcie_port - PCIe port information + * @base: I/O mapped register base + * @list: port list + * @pcie: pointer to PCIe host info + * @clk: pointer to the port clock gate + * @phy: pointer to PHY control block + * @pcie_rst: pointer to port reset control + * @gpio_rst: gpio reset + * @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 clk *clk; + struct phy *phy; + struct reset_control *pcie_rst; + struct gpio_desc *gpio_rst; + u32 slot; + bool enabled; +}; + +/** + * struct mt7621_pcie - PCIe host information + * @base: IO Mapped Register Base + * @dev: Pointer to PCIe device + * @ports: pointer to PCIe port information + * @resets_inverted: depends on chip revision + * reset lines are inverted. + */ +struct mt7621_pcie { + struct device *dev; + void __iomem *base; + struct list_head ports; + bool resets_inverted; +}; + +static inline u32 pcie_read(struct mt7621_pcie *pcie, u32 reg) +{ + return readl_relaxed(pcie->base + reg); +} + +static inline void pcie_write(struct mt7621_pcie *pcie, u32 val, u32 reg) +{ + writel_relaxed(val, pcie->base + reg); +} + +static inline u32 pcie_port_read(struct mt7621_pcie_port *port, u32 reg) +{ + return readl_relaxed(port->base + reg); +} + +static inline void pcie_port_write(struct mt7621_pcie_port *port, + u32 val, u32 reg) +{ + writel_relaxed(val, port->base + reg); +} + +static void __iomem *mt7621_pcie_map_bus(struct pci_bus *bus, + unsigned int devfn, int where) +{ + struct mt7621_pcie *pcie = bus->sysdata; + u32 address = PCI_CONF1_EXT_ADDRESS(bus->number, PCI_SLOT(devfn), + PCI_FUNC(devfn), where); + + writel_relaxed(address, pcie->base + RALINK_PCI_CONFIG_ADDR); + + return pcie->base + RALINK_PCI_CONFIG_DATA + (where & 3); +} + +static struct pci_ops mt7621_pcie_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 = PCI_CONF1_EXT_ADDRESS(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 = PCI_CONF1_EXT_ADDRESS(0, dev, 0, reg); + + pcie_write(pcie, address, RALINK_PCI_CONFIG_ADDR); + pcie_write(pcie, val, RALINK_PCI_CONFIG_DATA); +} + +static inline void mt7621_rst_gpio_pcie_assert(struct mt7621_pcie_port *port) +{ + if (port->gpio_rst) + gpiod_set_value(port->gpio_rst, 1); +} + +static inline void mt7621_rst_gpio_pcie_deassert(struct mt7621_pcie_port *port) +{ + if (port->gpio_rst) + gpiod_set_value(port->gpio_rst, 0); +} + +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_control_assert(struct mt7621_pcie_port *port) +{ + struct mt7621_pcie *pcie = port->pcie; + + if (pcie->resets_inverted) + reset_control_assert(port->pcie_rst); + else + reset_control_deassert(port->pcie_rst); +} + +static inline void mt7621_control_deassert(struct mt7621_pcie_port *port) +{ + struct mt7621_pcie *pcie = port->pcie; + + if (pcie->resets_inverted) + reset_control_deassert(port->pcie_rst); + else + reset_control_assert(port->pcie_rst); +} + +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 platform_device *pdev = to_platform_device(dev); + char name[10]; + int err; + + port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + port->base = devm_platform_ioremap_resource(pdev, slot + 1); + if (IS_ERR(port->base)) + return PTR_ERR(port->base); + + port->clk = devm_get_clk_from_child(dev, node, NULL); + if (IS_ERR(port->clk)) { + dev_err(dev, "failed to get pcie%d clock\n", slot); + return PTR_ERR(port->clk); + } + + port->pcie_rst = of_reset_control_get_exclusive(node, NULL); + 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_of_phy_get(dev, node, name); + if (IS_ERR(port->phy)) { + dev_err(dev, "failed to get pcie-phy%d\n", slot); + err = PTR_ERR(port->phy); + goto remove_reset; + } + + port->gpio_rst = devm_gpiod_get_index_optional(dev, "reset", slot, + GPIOD_OUT_LOW); + if (IS_ERR(port->gpio_rst)) { + dev_err(dev, "failed to get GPIO for PCIe%d\n", slot); + err = PTR_ERR(port->gpio_rst); + goto remove_reset; + } + + port->slot = slot; + port->pcie = pcie; + + INIT_LIST_HEAD(&port->list); + list_add_tail(&port->list, &pcie->ports); + + return 0; + +remove_reset: + reset_control_put(port->pcie_rst); + return err; +} + +static int mt7621_pcie_parse_dt(struct mt7621_pcie *pcie) +{ + struct device *dev = pcie->dev; + struct platform_device *pdev = to_platform_device(dev); + struct device_node *node = dev->of_node, *child; + int err; + + pcie->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(pcie->base)) + return PTR_ERR(pcie->base); + + 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; + + 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_reset_assert(struct mt7621_pcie *pcie) +{ + struct mt7621_pcie_port *port; + + list_for_each_entry(port, &pcie->ports, list) { + /* PCIe RC reset assert */ + mt7621_control_assert(port); + + /* PCIe EP reset assert */ + mt7621_rst_gpio_pcie_assert(port); + } + + msleep(PERST_DELAY_MS); +} + +static void mt7621_pcie_reset_rc_deassert(struct mt7621_pcie *pcie) +{ + struct mt7621_pcie_port *port; + + list_for_each_entry(port, &pcie->ports, list) + mt7621_control_deassert(port); +} + +static void mt7621_pcie_reset_ep_deassert(struct mt7621_pcie *pcie) +{ + struct mt7621_pcie_port *port; + + list_for_each_entry(port, &pcie->ports, list) + mt7621_rst_gpio_pcie_deassert(port); + + msleep(PERST_DELAY_MS); +} + +static int mt7621_pcie_init_ports(struct mt7621_pcie *pcie) +{ + struct device *dev = pcie->dev; + struct mt7621_pcie_port *port, *tmp; + u8 num_disabled = 0; + int err; + + mt7621_pcie_reset_assert(pcie); + mt7621_pcie_reset_rc_deassert(pcie); + + list_for_each_entry_safe(port, tmp, &pcie->ports, list) { + u32 slot = port->slot; + + if (slot == 1) { + port->enabled = true; + continue; + } + + err = mt7621_pcie_init_port(port); + if (err) { + dev_err(dev, "initializing port %d failed\n", slot); + list_del(&port->list); + } + } + + msleep(INIT_PORTS_DELAY_MS); + mt7621_pcie_reset_ep_deassert(pcie); + + tmp = NULL; + list_for_each_entry(port, &pcie->ports, list) { + u32 slot = port->slot; + + if (!mt7621_pcie_port_is_linkup(port)) { + dev_info(dev, "pcie%d no card, disable it (RST & CLK)\n", + slot); + mt7621_control_assert(port); + port->enabled = false; + num_disabled++; + + if (slot == 0) { + tmp = port; + continue; + } + + if (slot == 1 && tmp && !tmp->enabled) + phy_power_off(tmp->phy); + } + } + + return (num_disabled != PCIE_PORT_CNT) ? 0 : -ENODEV; +} + +static void mt7621_pcie_enable_port(struct mt7621_pcie_port *port) +{ + struct mt7621_pcie *pcie = port->pcie; + u32 slot = port->slot; + 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_port_write(port, PCIE_BAR_MAP_MAX | PCIE_BAR_ENABLE, + PCI_BASE_ADDRESS_0); + + /* configure class code and revision ID */ + pcie_port_write(port, PCIE_CLASS_CODE | PCIE_REVISION_ID, + RALINK_PCI_CLASS); + + /* 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_enable_ports(struct pci_host_bridge *host) +{ + struct mt7621_pcie *pcie = pci_host_bridge_priv(host); + struct device *dev = pcie->dev; + struct mt7621_pcie_port *port; + struct resource_entry *entry; + int err; + + entry = resource_list_first_type(&host->windows, IORESOURCE_IO); + if (!entry) { + dev_err(dev, "cannot get io resource\n"); + return -EINVAL; + } + + /* Setup MEMWIN and IOWIN */ + pcie_write(pcie, 0xffffffff, RALINK_PCI_MEMBASE); + pcie_write(pcie, entry->res->start - entry->offset, RALINK_PCI_IOBASE); + + list_for_each_entry(port, &pcie->ports, list) { + if (port->enabled) { + err = clk_prepare_enable(port->clk); + if (err) { + dev_err(dev, "enabling clk pcie%d\n", + port->slot); + return err; + } + + mt7621_pcie_enable_port(port); + dev_info(dev, "PCIE%d enabled\n", port->slot); + } + } + + return 0; +} + +static int mt7621_pcie_register_host(struct pci_host_bridge *host) +{ + struct mt7621_pcie *pcie = pci_host_bridge_priv(host); + + host->ops = &mt7621_pcie_ops; + host->sysdata = pcie; + return pci_host_probe(host); +} + +static const struct soc_device_attribute mt7621_pcie_quirks_match[] = { + { .soc_id = "mt7621", .revision = "E2" }, + { /* sentinel */ } +}; + +static int mt7621_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct soc_device_attribute *attr; + struct mt7621_pcie_port *port; + struct mt7621_pcie *pcie; + struct pci_host_bridge *bridge; + int err; + + 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); + + attr = soc_device_match(mt7621_pcie_quirks_match); + if (attr) + pcie->resets_inverted = true; + + err = mt7621_pcie_parse_dt(pcie); + if (err) { + dev_err(dev, "parsing DT failed\n"); + return err; + } + + err = mt7621_pcie_init_ports(pcie); + if (err) { + dev_err(dev, "nothing connected in virtual bridges\n"); + return 0; + } + + err = mt7621_pcie_enable_ports(bridge); + if (err) { + dev_err(dev, "error enabling pcie ports\n"); + goto remove_resets; + } + + return mt7621_pcie_register_host(bridge); + +remove_resets: + list_for_each_entry(port, &pcie->ports, list) + reset_control_put(port->pcie_rst); + + return err; +} + +static void mt7621_pcie_remove(struct platform_device *pdev) +{ + struct mt7621_pcie *pcie = platform_get_drvdata(pdev); + struct mt7621_pcie_port *port; + + list_for_each_entry(port, &pcie->ports, list) + reset_control_put(port->pcie_rst); +} + +static const struct of_device_id mt7621_pcie_ids[] = { + { .compatible = "mediatek,mt7621-pci" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mt7621_pcie_ids); + +static struct platform_driver mt7621_pcie_driver = { + .probe = mt7621_pcie_probe, + .remove_new = mt7621_pcie_remove, + .driver = { + .name = "mt7621-pci", + .of_match_table = mt7621_pcie_ids, + }, +}; +builtin_platform_driver(mt7621_pcie_driver); + +MODULE_LICENSE("GPL v2"); |