[PATCH 1/2] PCI: mediatek: Add Mediatek PCIe host controller support
From: Ryder Lee
Date: Sun Apr 23 2017 - 04:22:32 EST
Add support for the Mediatek PCIe controller which can be found
on MT7623A/N, MT2701 and MT8521p platforms.
Signed-off-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
---
drivers/pci/host/Kconfig | 11 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pcie-mediatek.c | 611 +++++++++++++++++++++++++++++++++++++++
3 files changed, 623 insertions(+)
create mode 100644 drivers/pci/host/pcie-mediatek.c
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index f7c1d4d..cf13b5d 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -174,6 +174,17 @@ config PCIE_ROCKCHIP
There is 1 internal PCIe port available to support GEN2 with
4 slots.
+config PCIE_MEDIATEK
+ bool "Mediatek PCIe Controller for MT7623 SoCs families"
+ depends on (ARM && ARCH_MEDIATEK) || COMPILE_TEST
+ depends on OF
+ depends on PCI
+ select PCIEPORTBUS
+ help
+ Say Y here if you want to enable PCIe controller support on MT7623 A/N
+ series SoCs. There is a one root complex with 3 root ports available.
+ Each port supports Gen2 lane x1.
+
config VMD
depends on PCI_MSI && X86_64 && SRCU
tristate "Intel Volume Management Device Driver"
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 4d36866..265adff 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_PCIE_IPROC_BCMA) += pcie-iproc-bcma.o
obj-$(CONFIG_PCIE_ALTERA) += pcie-altera.o
obj-$(CONFIG_PCIE_ALTERA_MSI) += pcie-altera-msi.o
obj-$(CONFIG_PCIE_ROCKCHIP) += pcie-rockchip.o
+obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
obj-$(CONFIG_VMD) += vmd.o
# The following drivers are for devices that use the generic ACPI
diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c
new file mode 100644
index 0000000..98e84d9
--- /dev/null
+++ b/drivers/pci/host/pcie-mediatek.c
@@ -0,0 +1,611 @@
+/*
+ * PCIe host controller driver for Mediatek MT7623 SoCs families
+ *
+ * Copyright (c) 2017 MediaTek Inc.
+ * Author: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
+ *
+ * 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/module.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_BAR1_SETUP 0x14
+#define PCIE_BAR0_MEM_BASE 0x18
+#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
+ * @dev: pointer to root port device
+ * @base: IO mapped register base
+ * @list: port list
+ * @pcie: pointer to PCIe host info
+ * @reset: pointer to RC reset control
+ * @regs: port memory region
+ * @sys_ck: root port clock
+ * @phy: pointer to phy control block
+ * @irq: IRQ number
+ * @lane: lane count
+ * @index: port index
+ */
+struct mtk_pcie_port {
+ struct device *dev;
+ void __iomem *base;
+ struct list_head list;
+ struct mtk_pcie *pcie;
+ struct reset_control *reset;
+ struct resource regs;
+ struct clk *sys_ck;
+ struct phy *phy;
+ int irq;
+ 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
+ * @resources: bus resources
+ * @ports: pointer to PCIe port information
+ */
+struct mtk_pcie {
+ struct device *dev;
+ void __iomem *base;
+ struct clk *free_ck;
+ struct list_head resources;
+ struct list_head ports;
+};
+
+static inline bool mtk_pcie_link_is_up(struct mtk_pcie_port *port)
+{
+ return !!(readl_relaxed(port->base + PCIE_LINK_STATUS) &
+ PCIE_PORT_LINKUP);
+}
+
+static bool mtk_pcie_valid_device(struct mtk_pcie *pcie,
+ struct pci_bus *bus, int devfn)
+{
+ struct mtk_pcie_port *port;
+ struct pci_dev *dev;
+ struct pci_bus *pbus;
+
+ /* if there is no link, then there is no device */
+ list_for_each_entry(port, &pcie->ports, list) {
+ if (bus->number == 0 && port->index == PCI_SLOT(devfn) &&
+ mtk_pcie_link_is_up(port)) {
+ return true;
+ } else if (bus->number != 0) {
+ pbus = bus;
+ do {
+ dev = pbus->self;
+ if (port->index == PCI_SLOT(dev->devfn) &&
+ mtk_pcie_link_is_up(port)) {
+ return true;
+ }
+ pbus = dev->bus;
+ } while (dev->bus->number != 0);
+ }
+ }
+
+ return false;
+}
+
+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);
+ devm_release_mem_region(dev, port->regs.start,
+ resource_size(&port->regs));
+ list_del(&port->list);
+ devm_kfree(dev, port);
+}
+
+static int mtk_pcie_hw_rd_cfg(struct mtk_pcie *pcie, u32 bus, u32 devfn,
+ int where, int size, u32 *val)
+{
+ writel(PCIE_CONF_ADDR(where, PCI_FUNC(devfn), PCI_SLOT(devfn), bus),
+ pcie->base + PCIE_CFG_ADDR);
+
+ *val = 0;
+
+ switch (size) {
+ case 1:
+ *val = readb(pcie->base + PCIE_CFG_DATA + (where & 3));
+ break;
+ case 2:
+ *val = readw(pcie->base + PCIE_CFG_DATA + (where & 2));
+ break;
+ case 4:
+ *val = readl(pcie->base + PCIE_CFG_DATA);
+ break;
+ }
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int mtk_pcie_hw_wr_cfg(struct mtk_pcie *pcie, u32 bus, u32 devfn,
+ int where, int size, u32 val)
+
+{
+ writel(PCIE_CONF_ADDR(where, PCI_FUNC(devfn), PCI_SLOT(devfn), bus),
+ pcie->base + PCIE_CFG_ADDR);
+
+ switch (size) {
+ case 1:
+ writeb(val, pcie->base + PCIE_CFG_DATA + (where & 3));
+ break;
+ case 2:
+ writew(val, pcie->base + PCIE_CFG_DATA + (where & 2));
+ break;
+ case 4:
+ writel(val, pcie->base + PCIE_CFG_DATA);
+ break;
+ }
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int mtk_pcie_read_config(struct pci_bus *bus, u32 devfn,
+ int where, int size, u32 *val)
+{
+ struct mtk_pcie *pcie = bus->sysdata;
+ u32 bn = bus->number;
+
+ if (!mtk_pcie_valid_device(pcie, bus, devfn)) {
+ *val = 0xffffffff;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ return mtk_pcie_hw_rd_cfg(pcie, bn, devfn, where, size, val);
+}
+
+static int mtk_pcie_write_config(struct pci_bus *bus, u32 devfn,
+ int where, int size, u32 val)
+{
+ struct mtk_pcie *pcie = bus->sysdata;
+ u32 bn = bus->number;
+
+ if (!mtk_pcie_valid_device(pcie, bus, devfn))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return mtk_pcie_hw_wr_cfg(pcie, bn, devfn, where, size, val);
+}
+
+static struct pci_ops mtk_pcie_ops = {
+ .read = mtk_pcie_read_config,
+ .write = mtk_pcie_write_config,
+};
+
+static void mtk_pcie_configure_rc(struct mtk_pcie_port *port)
+{
+ struct mtk_pcie *pcie = port->pcie;
+ 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 */
+ mtk_pcie_hw_rd_cfg(pcie, 0, (port->index << 3),
+ PCIE_FC_CREDIT, 4, &val);
+ val &= ~PCIE_FC_CREDIT_MASK;
+ val |= PCIE_FC_CREDIT_VAL(0x806c);
+ mtk_pcie_hw_wr_cfg(pcie, 0, (port->index << 3),
+ PCIE_FC_CREDIT, 4, val);
+
+ /* configure RC FTS number to 250 when it leaves L0s */
+ mtk_pcie_hw_rd_cfg(pcie, 0, (port->index << 3),
+ PCIE_FTS_NUM, 4, &val);
+ val &= ~PCIE_FTS_NUM_MASK;
+ val |= PCIE_FTS_NUM_L0(0x50);
+ mtk_pcie_hw_wr_cfg(pcie, 0, (port->index << 3),
+ PCIE_FTS_NUM, 4, val);
+}
+
+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);
+
+ /*
+ * at least 100ms delay because PCIe v2.0 need more time to
+ * train from Gen1 to Gen2
+ */
+ msleep(100);
+}
+
+static int mtk_pcie_enable_ports(struct mtk_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ struct mtk_pcie_port *port, *tmp;
+ int err, linkup = 0;
+
+ list_for_each_entry_safe(port, tmp, &pcie->ports, list) {
+ err = clk_prepare_enable(port->sys_ck);
+ if (err) {
+ dev_err(dev, "failed to enable port%d clock\n",
+ port->index);
+ continue;
+ }
+
+ /* assert RC */
+ reset_control_assert(port->reset);
+ /* de-assert RC */
+ reset_control_deassert(port->reset);
+
+ /* power on PHY */
+ 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_is_up(port)) {
+ mtk_pcie_configure_rc(port);
+ linkup++;
+ continue;
+ }
+
+ dev_info(dev, "Port%d link down\n", port->index);
+
+ phy_power_off(port->phy);
+err_phy_on:
+ clk_disable_unprepare(port->sys_ck);
+ mtk_pcie_port_free(port);
+ }
+
+ return linkup;
+}
+
+static int mtk_pcie_get_port_resource(struct mtk_pcie_port *port,
+ struct device_node *node)
+{
+ struct device *dev = port->pcie->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct platform_device *plat_dev;
+ char name[10];
+ int err;
+
+ err = of_address_to_resource(node, 0, &port->regs);
+ if (err) {
+ dev_err(dev, "failed to parse address: %d\n", err);
+ return err;
+ }
+
+ port->base = devm_ioremap_resource(dev, &port->regs);
+ if (IS_ERR(port->base)) {
+ dev_err(dev, "failed to map port%d base\n", port->index);
+ return PTR_ERR(port->base);
+ }
+
+ plat_dev = of_find_device_by_node(node);
+ if (!plat_dev) {
+ plat_dev = of_platform_device_create(
+ node, NULL,
+ platform_bus_type.dev_root);
+ if (!plat_dev)
+ return -EPROBE_DEFER;
+ }
+
+ port->dev = &plat_dev->dev;
+
+ port->irq = platform_get_irq(pdev, port->index);
+ if (!port->irq) {
+ dev_err(dev, "failed to get irq\n");
+ return -ENODEV;
+ }
+
+ port->sys_ck = devm_clk_get(port->dev, "sys_ck");
+ if (IS_ERR(port->sys_ck)) {
+ dev_err(port->dev, "failed to get port%d clock\n", port->index);
+ return PTR_ERR(port->sys_ck);
+ }
+
+ port->reset = devm_reset_control_get(port->dev, "pcie-reset");
+ if (IS_ERR(port->reset)) {
+ dev_err(port->dev, "failed to get port%d reset control\n",
+ port->index);
+ return PTR_ERR(port->reset);
+ }
+
+ snprintf(name, sizeof(name), "pcie-phy%d", port->index);
+ port->phy = devm_of_phy_get(port->dev, node, name);
+ if (IS_ERR(port->phy)) {
+ dev_err(port->dev, "failed to get port%d phy\n", port->index);
+ return PTR_ERR(port->phy);
+ }
+
+ return 0;
+}
+
+static int mtk_pcie_parse_and_add_res(struct mtk_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct device_node *node = dev->of_node, *child;
+ struct resource_entry *win, *tmp;
+ struct resource *regs;
+ resource_size_t iobase;
+ int err;
+
+ /* parse shared resources */
+ 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 get PCIe base\n");
+ return PTR_ERR(pcie->base);
+ }
+
+ pcie->free_ck = devm_clk_get(dev, "free_ck");
+ if (IS_ERR(pcie->free_ck)) {
+ dev_err(dev, "failed to get free_ck\n");
+ return PTR_ERR(pcie->free_ck);
+ }
+
+ err = of_pci_get_host_bridge_resources(node, 0, 0xff, &pcie->resources,
+ &iobase);
+ if (err)
+ return err;
+
+ err = devm_request_pci_bus_resources(dev, &pcie->resources);
+ if (err)
+ return err;
+
+ resource_list_for_each_entry_safe(win, tmp, &pcie->resources) {
+ struct resource *res = win->res;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
+ err = pci_remap_iospace(res, iobase);
+ if (err) {
+ dev_warn(dev, "failed to map resource %pR\n",
+ res);
+ resource_list_destroy_entry(win);
+ }
+ break;
+ }
+ }
+
+ /* parse port resources */
+ for_each_child_of_node(node, child) {
+ struct mtk_pcie_port *port;
+ int index;
+
+ err = of_pci_get_devfn(child);
+ if (err < 0) {
+ dev_err(pcie->dev, "failed to parse devfn: %d\n", err);
+ return err;
+ }
+
+ index = PCI_SLOT(err);
+ if (index < 1) {
+ dev_err(dev, "invalid port number: %d\n", index);
+ return -EINVAL;
+ }
+
+ index--;
+
+ if (!of_device_is_available(child))
+ continue;
+
+ port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ err = of_property_read_u32(child, "num-lanes", &port->lane);
+ if (err) {
+ dev_err(dev, "missing num-lanes property\n");
+ return err;
+ }
+
+ port->index = index;
+ port->pcie = pcie;
+
+ err = mtk_pcie_get_port_resource(port, child);
+ if (err)
+ return err;
+
+ INIT_LIST_HEAD(&port->list);
+ list_add_tail(&port->list, &pcie->ports);
+ }
+
+ return 0;
+}
+
+/*
+ * This IP lacks interrupt status register to check or map INTx from
+ * different devices at the same time.
+ */
+static int __init mtk_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+ struct mtk_pcie *pcie = dev->bus->sysdata;
+ struct mtk_pcie_port *port;
+
+ list_for_each_entry(port, &pcie->ports, list)
+ if (port->index == slot)
+ return port->irq;
+
+ return -1;
+}
+
+static int mtk_pcie_register_ports(struct mtk_pcie *pcie)
+{
+ struct pci_bus *bus, *child;
+
+ bus = pci_scan_root_bus(pcie->dev, 0, &mtk_pcie_ops, pcie,
+ &pcie->resources);
+ if (!bus) {
+ dev_err(pcie->dev, "failed to create root bus\n");
+ return -ENOMEM;
+ }
+
+ if (!pci_has_flag(PCI_PROBE_ONLY)) {
+ pci_fixup_irqs(pci_common_swizzle, mtk_pcie_map_irq);
+ pci_bus_size_bridges(bus);
+ pci_bus_assign_resources(bus);
+
+ list_for_each_entry(child, &bus->children, node)
+ pcie_bus_configure_settings(child);
+ }
+
+ pci_bus_add_devices(bus);
+
+ return 0;
+}
+
+static int mtk_pcie_probe(struct platform_device *pdev)
+{
+ struct mtk_pcie *pcie;
+ int err;
+
+ pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
+ if (!pcie)
+ return -ENOMEM;
+
+ pcie->dev = &pdev->dev;
+ platform_set_drvdata(pdev, pcie);
+
+ /*
+ * parse PCI ranges, configuration bus range and
+ * request their resources
+ */
+ INIT_LIST_HEAD(&pcie->ports);
+ INIT_LIST_HEAD(&pcie->resources);
+
+ err = mtk_pcie_parse_and_add_res(pcie);
+ if (err)
+ goto err_parse;
+
+ pm_runtime_enable(pcie->dev);
+ err = pm_runtime_get_sync(pcie->dev);
+ if (err)
+ goto err_pm;
+
+ err = clk_prepare_enable(pcie->free_ck);
+ if (err) {
+ dev_err(pcie->dev, "failed to enable free_ck\n");
+ goto err_free_ck;
+ }
+
+ /* power on PCIe ports */
+ err = mtk_pcie_enable_ports(pcie);
+ if (!err)
+ goto err_enable;
+
+ /* register PCIe ports */
+ err = mtk_pcie_register_ports(pcie);
+ if (err)
+ goto err_enable;
+
+ return 0;
+
+err_enable:
+ clk_disable_unprepare(pcie->free_ck);
+err_free_ck:
+ pm_runtime_put_sync(pcie->dev);
+err_pm:
+ pm_runtime_disable(pcie->dev);
+err_parse:
+ pci_free_resource_list(&pcie->resources);
+
+ return err;
+}
+
+static const struct of_device_id mtk_pcie_ids[] = {
+ { .compatible = "mediatek,mt7623-pcie"},
+ { .compatible = "mediatek,mt2701-pcie"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtk_pcie_ids);
+
+static struct platform_driver mtk_pcie_driver = {
+ .probe = mtk_pcie_probe,
+ .driver = {
+ .name = "mtk-pcie",
+ .of_match_table = mtk_pcie_ids,
+ },
+};
+
+builtin_platform_driver(mtk_pcie_driver);
+
+MODULE_DESCRIPTION("Mediatek PCIe host driver for MT7623 SoCs families");
+MODULE_LICENSE("GPL v2");
--
1.9.1