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path: root/drivers/pci/controller/pcie-mt7621.c
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Diffstat (limited to 'drivers/pci/controller/pcie-mt7621.c')
-rw-r--r--drivers/pci/controller/pcie-mt7621.c600
1 files changed, 600 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-mt7621.c b/drivers/pci/controller/pcie-mt7621.c
new file mode 100644
index 000000000000..b60dfb45ef7b
--- /dev/null
+++ b/drivers/pci/controller/pcie-mt7621.c
@@ -0,0 +1,600 @@
+// 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>
+
+/* 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 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 {
+ void __iomem *base;
+ struct device *dev;
+ 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 void pcie_rmw(struct mt7621_pcie *pcie, u32 reg, u32 clr, u32 set)
+{
+ u32 val = readl_relaxed(pcie->base + reg);
+
+ val &= ~clr;
+ val |= set;
+ 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 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_relaxed(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_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 setup_cm_memory_region(struct pci_host_bridge *host)
+{
+ struct mt7621_pcie *pcie = pci_host_bridge_priv(host);
+ struct device *dev = pcie->dev;
+ struct resource_entry *entry;
+ resource_size_t mask;
+
+ entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
+ if (!entry) {
+ dev_err(dev, "cannot get memory resource\n");
+ return -EINVAL;
+ }
+
+ 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 = ~(entry->res->end - entry->res->start);
+
+ write_gcr_reg1_base(entry->res->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());
+ }
+
+ 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 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);
+ }
+ }
+
+ 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_err(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_pci_ops;
+ host->sysdata = pcie;
+ return pci_host_probe(host);
+}
+
+static const struct soc_device_attribute mt7621_pci_quirks_match[] = {
+ { .soc_id = "mt7621", .revision = "E2" }
+};
+
+static int mt7621_pci_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_pci_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;
+ }
+
+ err = setup_cm_memory_region(bridge);
+ if (err) {
+ dev_err(dev, "error setting up iocu mem regions\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 int mt7621_pci_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);
+
+ 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,
+ .remove = mt7621_pci_remove,
+ .driver = {
+ .name = "mt7621-pci",
+ .of_match_table = of_match_ptr(mt7621_pci_ids),
+ },
+};
+builtin_platform_driver(mt7621_pci_driver);