--- /dev/null
+/*
+ * MediaTek PCIe host controller driver.
+ *
+ * Copyright (c) 2017 MediaTek Inc.
+ * Author: Ryder Lee <ryder.lee@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/kernel.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/pm_runtime.h>
+#include <linux/reset.h>
+
+/* PCIe shared registers */
+#define PCIE_SYS_CFG 0x00
+#define PCIE_INT_ENABLE 0x0c
+#define PCIE_CFG_ADDR 0x20
+#define PCIE_CFG_DATA 0x24
+
+/* PCIe per port registers */
+#define PCIE_BAR0_SETUP 0x10
+#define PCIE_CLASS 0x34
+#define PCIE_LINK_STATUS 0x50
+
+#define PCIE_PORT_INT_EN(x) BIT(20 + (x))
+#define PCIE_PORT_PERST(x) BIT(1 + (x))
+#define PCIE_PORT_LINKUP BIT(0)
+#define PCIE_BAR_MAP_MAX GENMASK(31, 16)
+
+#define PCIE_BAR_ENABLE BIT(0)
+#define PCIE_REVISION_ID BIT(0)
+#define PCIE_CLASS_CODE (0x60400 << 8)
+#define PCIE_CONF_REG(regn) (((regn) & GENMASK(7, 2)) | \
+ ((((regn) >> 8) & GENMASK(3, 0)) << 24))
+#define PCIE_CONF_FUN(fun) (((fun) << 8) & GENMASK(10, 8))
+#define PCIE_CONF_DEV(dev) (((dev) << 11) & GENMASK(15, 11))
+#define PCIE_CONF_BUS(bus) (((bus) << 16) & GENMASK(23, 16))
+#define PCIE_CONF_ADDR(regn, fun, dev, bus) \
+ (PCIE_CONF_REG(regn) | PCIE_CONF_FUN(fun) | \
+ PCIE_CONF_DEV(dev) | PCIE_CONF_BUS(bus))
+
+/* 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)
+
+#define PCIE_FC_CREDIT 0x73c
+#define PCIE_FC_CREDIT_MASK (GENMASK(31, 31) | GENMASK(28, 16))
+#define PCIE_FC_CREDIT_VAL(x) ((x) << 16)
+
+/**
+ * struct mtk_pcie_port - PCIe port information
+ * @base: IO mapped register base
+ * @list: port list
+ * @pcie: pointer to PCIe host info
+ * @reset: pointer to port reset control
+ * @sys_ck: pointer to bus clock
+ * @phy: pointer to phy control block
+ * @lane: lane count
+ * @index: port index
+ */
+struct mtk_pcie_port {
+ void __iomem *base;
+ struct list_head list;
+ struct mtk_pcie *pcie;
+ struct reset_control *reset;
+ struct clk *sys_ck;
+ struct phy *phy;
+ u32 lane;
+ u32 index;
+};
+
+/**
+ * struct mtk_pcie - PCIe host information
+ * @dev: pointer to PCIe device
+ * @base: IO mapped register base
+ * @free_ck: free-run reference clock
+ * @io: IO resource
+ * @pio: PIO resource
+ * @mem: non-prefetchable memory resource
+ * @busn: bus range
+ * @offset: IO / Memory offset
+ * @ports: pointer to PCIe port information
+ */
+struct mtk_pcie {
+ struct device *dev;
+ void __iomem *base;
+ struct clk *free_ck;
+
+ struct resource io;
+ struct resource pio;
+ struct resource mem;
+ struct resource busn;
+ struct {
+ resource_size_t mem;
+ resource_size_t io;
+ } offset;
+ struct list_head ports;
+};
+
+static inline bool mtk_pcie_link_up(struct mtk_pcie_port *port)
+{
+ return !!(readl(port->base + PCIE_LINK_STATUS) & PCIE_PORT_LINKUP);
+}
+
+static void mtk_pcie_subsys_powerdown(struct mtk_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+
+ clk_disable_unprepare(pcie->free_ck);
+
+ if (dev->pm_domain) {
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+ }
+}
+
+static void mtk_pcie_port_free(struct mtk_pcie_port *port)
+{
+ struct mtk_pcie *pcie = port->pcie;
+ struct device *dev = pcie->dev;
+
+ devm_iounmap(dev, port->base);
+ list_del(&port->list);
+ devm_kfree(dev, port);
+}
+
+static void mtk_pcie_put_resources(struct mtk_pcie *pcie)
+{
+ struct mtk_pcie_port *port, *tmp;
+
+ list_for_each_entry_safe(port, tmp, &pcie->ports, list) {
+ phy_power_off(port->phy);
+ clk_disable_unprepare(port->sys_ck);
+ mtk_pcie_port_free(port);
+ }
+
+ mtk_pcie_subsys_powerdown(pcie);
+}
+
+static void __iomem *mtk_pcie_map_bus(struct pci_bus *bus,
+ unsigned int devfn, int where)
+{
+ struct pci_host_bridge *host = pci_find_host_bridge(bus);
+ struct mtk_pcie *pcie = pci_host_bridge_priv(host);
+
+ writel(PCIE_CONF_ADDR(where, PCI_FUNC(devfn), PCI_SLOT(devfn),
+ bus->number), pcie->base + PCIE_CFG_ADDR);
+
+ return pcie->base + PCIE_CFG_DATA + (where & 3);
+}
+
+static struct pci_ops mtk_pcie_ops = {
+ .map_bus = mtk_pcie_map_bus,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+};
+
+static void mtk_pcie_configure_rc(struct mtk_pcie_port *port)
+{
+ struct mtk_pcie *pcie = port->pcie;
+ u32 func = PCI_FUNC(port->index << 3);
+ u32 slot = PCI_SLOT(port->index << 3);
+ u32 val;
+
+ /* enable interrupt */
+ val = readl(pcie->base + PCIE_INT_ENABLE);
+ val |= PCIE_PORT_INT_EN(port->index);
+ writel(val, pcie->base + PCIE_INT_ENABLE);
+
+ /* map to all DDR region. We need to set it before cfg operation. */
+ writel(PCIE_BAR_MAP_MAX | PCIE_BAR_ENABLE,
+ port->base + PCIE_BAR0_SETUP);
+
+ /* configure class code and revision ID */
+ writel(PCIE_CLASS_CODE | PCIE_REVISION_ID, port->base + PCIE_CLASS);
+
+ /* configure FC credit */
+ writel(PCIE_CONF_ADDR(PCIE_FC_CREDIT, func, slot, 0),
+ pcie->base + PCIE_CFG_ADDR);
+ val = readl(pcie->base + PCIE_CFG_DATA);
+ val &= ~PCIE_FC_CREDIT_MASK;
+ val |= PCIE_FC_CREDIT_VAL(0x806c);
+ writel(PCIE_CONF_ADDR(PCIE_FC_CREDIT, func, slot, 0),
+ pcie->base + PCIE_CFG_ADDR);
+ writel(val, pcie->base + PCIE_CFG_DATA);
+
+ /* configure RC FTS number to 250 when it leaves L0s */
+ writel(PCIE_CONF_ADDR(PCIE_FTS_NUM, func, slot, 0),
+ pcie->base + PCIE_CFG_ADDR);
+ val = readl(pcie->base + PCIE_CFG_DATA);
+ val &= ~PCIE_FTS_NUM_MASK;
+ val |= PCIE_FTS_NUM_L0(0x50);
+ writel(PCIE_CONF_ADDR(PCIE_FTS_NUM, func, slot, 0),
+ pcie->base + PCIE_CFG_ADDR);
+ writel(val, pcie->base + PCIE_CFG_DATA);
+}
+
+static void mtk_pcie_assert_ports(struct mtk_pcie_port *port)
+{
+ struct mtk_pcie *pcie = port->pcie;
+ u32 val;
+
+ /* assert port PERST_N */
+ val = readl(pcie->base + PCIE_SYS_CFG);
+ val |= PCIE_PORT_PERST(port->index);
+ writel(val, pcie->base + PCIE_SYS_CFG);
+
+ /* de-assert port PERST_N */
+ val = readl(pcie->base + PCIE_SYS_CFG);
+ val &= ~PCIE_PORT_PERST(port->index);
+ writel(val, pcie->base + PCIE_SYS_CFG);
+
+ /* PCIe v2.0 need at least 100ms delay to train from Gen1 to Gen2 */
+ msleep(100);
+}
+
+static void mtk_pcie_enable_ports(struct mtk_pcie_port *port)
+{
+ struct device *dev = port->pcie->dev;
+ int err;
+
+ err = clk_prepare_enable(port->sys_ck);
+ if (err) {
+ dev_err(dev, "failed to enable port%d clock\n", port->index);
+ goto err_sys_clk;
+ }
+
+ reset_control_assert(port->reset);
+ reset_control_deassert(port->reset);
+
+ err = phy_power_on(port->phy);
+ if (err) {
+ dev_err(dev, "failed to power on port%d phy\n", port->index);
+ goto err_phy_on;
+ }
+
+ mtk_pcie_assert_ports(port);
+
+ /* if link up, then setup root port configuration space */
+ if (mtk_pcie_link_up(port)) {
+ mtk_pcie_configure_rc(port);
+ return;
+ }
+
+ dev_info(dev, "Port%d link down\n", port->index);
+
+ phy_power_off(port->phy);
+err_phy_on:
+ clk_disable_unprepare(port->sys_ck);
+err_sys_clk:
+ mtk_pcie_port_free(port);
+}
+
+static int mtk_pcie_parse_ports(struct mtk_pcie *pcie,
+ struct device_node *node,
+ int index)
+{
+ struct mtk_pcie_port *port;
+ struct resource *regs;
+ 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;
+
+ err = of_property_read_u32(node, "num-lanes", &port->lane);
+ if (err) {
+ dev_err(dev, "missing num-lanes property\n");
+ return err;
+ }
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, index + 1);
+ port->base = devm_ioremap_resource(dev, regs);
+ if (IS_ERR(port->base)) {
+ dev_err(dev, "failed to map port%d base\n", index);
+ return PTR_ERR(port->base);
+ }
+
+ snprintf(name, sizeof(name), "sys_ck%d", index);
+ port->sys_ck = devm_clk_get(dev, name);
+ if (IS_ERR(port->sys_ck)) {
+ dev_err(dev, "failed to get port%d clock\n", index);
+ return PTR_ERR(port->sys_ck);
+ }
+
+ snprintf(name, sizeof(name), "pcie-rst%d", index);
+ port->reset = devm_reset_control_get_optional(dev, name);
+ if (PTR_ERR(port->reset) == -EPROBE_DEFER)
+ return PTR_ERR(port->reset);
+
+ /* some platforms may use default PHY setting */
+ snprintf(name, sizeof(name), "pcie-phy%d", index);
+ port->phy = devm_phy_optional_get(dev, name);
+ if (IS_ERR(port->phy))
+ return PTR_ERR(port->phy);
+
+ port->index = index;
+ port->pcie = pcie;
+
+ INIT_LIST_HEAD(&port->list);
+ list_add_tail(&port->list, &pcie->ports);
+
+ return 0;
+}
+
+static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *regs;
+ int err;
+
+ /* get shared registers */
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pcie->base = devm_ioremap_resource(dev, regs);
+ if (IS_ERR(pcie->base)) {
+ dev_err(dev, "failed to map shared register\n");
+ return PTR_ERR(pcie->base);
+ }
+
+ pcie->free_ck = devm_clk_get(dev, "free_ck");
+ if (IS_ERR(pcie->free_ck)) {
+ if (PTR_ERR(pcie->free_ck) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ pcie->free_ck = NULL;
+ }
+
+ if (dev->pm_domain) {
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+ }
+
+ /* enable top level clock */
+ err = clk_prepare_enable(pcie->free_ck);
+ if (err) {
+ dev_err(dev, "failed to enable free_ck\n");
+ goto err_free_ck;
+ }
+
+ return 0;
+
+err_free_ck:
+ if (dev->pm_domain) {
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+ }
+
+ return err;
+}
+
+static int mtk_pcie_setup(struct mtk_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ struct device_node *node = dev->of_node, *child;
+ struct of_pci_range_parser parser;
+ struct of_pci_range range;
+ struct resource res;
+ struct mtk_pcie_port *port, *tmp;
+ 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) {
+ err = of_pci_range_to_resource(&range, node, &res);
+ if (err < 0)
+ return err;
+
+ switch (res.flags & IORESOURCE_TYPE_BITS) {
+ case IORESOURCE_IO:
+ pcie->offset.io = res.start - range.pci_addr;
+
+ memcpy(&pcie->pio, &res, sizeof(res));
+ pcie->pio.name = node->full_name;
+
+ pcie->io.start = range.cpu_addr;
+ pcie->io.end = range.cpu_addr + range.size - 1;
+ pcie->io.flags = IORESOURCE_MEM;
+ pcie->io.name = "I/O";
+
+ memcpy(&res, &pcie->io, sizeof(res));
+ break;
+
+ case IORESOURCE_MEM:
+ pcie->offset.mem = res.start - range.pci_addr;
+
+ memcpy(&pcie->mem, &res, sizeof(res));
+ pcie->mem.name = "non-prefetchable";
+ break;
+ }
+ }
+
+ 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;
+ }
+
+ for_each_available_child_of_node(node, child) {
+ int index;
+
+ err = of_pci_get_devfn(child);
+ if (err < 0) {
+ dev_err(dev, "failed to parse devfn: %d\n", err);
+ return err;
+ }
+
+ index = PCI_SLOT(err);
+
+ err = mtk_pcie_parse_ports(pcie, child, index);
+ if (err)
+ return err;
+ }
+
+ err = mtk_pcie_subsys_powerup(pcie);
+ if (err)
+ return err;
+
+ /* enable each port, and then check link status */
+ list_for_each_entry_safe(port, tmp, &pcie->ports, list)
+ mtk_pcie_enable_ports(port);
+
+ /* power down PCIe subsys if slots are all empty (link down) */
+ if (list_empty(&pcie->ports))
+ mtk_pcie_subsys_powerdown(pcie);
+
+ return 0;
+}
+
+static int mtk_pcie_request_resources(struct mtk_pcie *pcie)
+{
+ struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
+ struct list_head *windows = &host->windows;
+ struct device *dev = pcie->dev;
+ int err;
+
+ pci_add_resource_offset(windows, &pcie->pio, pcie->offset.io);
+ pci_add_resource_offset(windows, &pcie->mem, pcie->offset.mem);
+ pci_add_resource(windows, &pcie->busn);
+
+ err = devm_request_pci_bus_resources(dev, windows);
+ if (err < 0)
+ return err;
+
+ pci_remap_iospace(&pcie->pio, pcie->io.start);
+
+ return 0;
+}
+
+static int mtk_pcie_register_host(struct pci_host_bridge *host)
+{
+ struct mtk_pcie *pcie = pci_host_bridge_priv(host);
+ struct pci_bus *child;
+ int err;
+
+ host->busnr = pcie->busn.start;
+ host->dev.parent = pcie->dev;
+ host->ops = &mtk_pcie_ops;
+ host->map_irq = of_irq_parse_and_map_pci;
+ host->swizzle_irq = pci_common_swizzle;
+
+ err = pci_scan_root_bus_bridge(host);
+ if (err < 0)
+ return err;
+
+ pci_bus_size_bridges(host->bus);
+ pci_bus_assign_resources(host->bus);
+
+ list_for_each_entry(child, &host->bus->children, node)
+ pcie_bus_configure_settings(child);
+
+ pci_bus_add_devices(host->bus);
+
+ return 0;
+}
+
+static int mtk_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mtk_pcie *pcie;
+ struct pci_host_bridge *host;
+ int err;
+
+ host = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
+ if (!host)
+ return -ENOMEM;
+
+ pcie = pci_host_bridge_priv(host);
+
+ pcie->dev = dev;
+ platform_set_drvdata(pdev, pcie);
+ INIT_LIST_HEAD(&pcie->ports);
+
+ err = mtk_pcie_setup(pcie);
+ if (err)
+ return err;
+
+ err = mtk_pcie_request_resources(pcie);
+ if (err)
+ goto put_resources;
+
+ err = mtk_pcie_register_host(host);
+ if (err)
+ goto put_resources;
+
+ return 0;
+
+put_resources:
+ if (!list_empty(&pcie->ports))
+ mtk_pcie_put_resources(pcie);
+
+ return err;
+}
+
+static const struct of_device_id mtk_pcie_ids[] = {
+ { .compatible = "mediatek,mt7623-pcie"},
+ { .compatible = "mediatek,mt2701-pcie"},
+ {},
+};
+
+static struct platform_driver mtk_pcie_driver = {
+ .probe = mtk_pcie_probe,
+ .driver = {
+ .name = "mtk-pcie",
+ .of_match_table = mtk_pcie_ids,
+ .suppress_bind_attrs = true,
+ },
+};
+builtin_platform_driver(mtk_pcie_driver);
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff