--- /dev/null
+/*
+ * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ * Copyright 2015 Linaro Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+
+#define PCIE20_PARF_PHY_CTRL 0x40
+#define PCIE20_PARF_PHY_REFCLK 0x4C
+#define PCIE20_PARF_DBI_BASE_ADDR 0x168
+#define PCIE20_PARF_SLV_ADDR_SPACE_SIZE 0x16c
+#define PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT 0x178
+
+#define PCIE20_ELBI_SYS_CTRL 0x04
+#define PCIE20_ELBI_SYS_CTRL_LT_ENABLE BIT(0)
+
+#define PCIE20_ELBI_SYS_STTS 0x08
+#define XMLH_LINK_UP BIT(10)
+
+#define PCIE20_CAP 0x70
+#define PCIE20_CAP_LINKCTRLSTATUS (PCIE20_CAP + 0x10)
+#define PCIE20_CAP_LINKCTRLSTATUS_LINK_UP BIT(29)
+
+#define PERST_DELAY_US 1000
+
+#define LINKUP_DELAY_US 5000
+#define LINKUP_TIMEOUT_US 100000
+
+struct qcom_pcie_resources_v0 {
+ struct clk *iface_clk;
+ struct clk *core_clk;
+ struct clk *phy_clk;
+ struct reset_control *pci_reset;
+ struct reset_control *axi_reset;
+ struct reset_control *ahb_reset;
+ struct reset_control *por_reset;
+ struct reset_control *phy_reset;
+ struct regulator *vdda;
+ struct regulator *vdda_phy;
+ struct regulator *vdda_refclk;
+};
+
+struct qcom_pcie_resources_v1 {
+ struct clk *iface;
+ struct clk *aux;
+ struct clk *master_bus;
+ struct clk *slave_bus;
+ struct reset_control *core;
+ struct regulator *vdda;
+};
+
+union qcom_pcie_resources {
+ struct qcom_pcie_resources_v0 v0;
+ struct qcom_pcie_resources_v1 v1;
+};
+
+struct qcom_pcie;
+
+struct qcom_pcie_ops {
+ int (*get_resources)(struct qcom_pcie *pcie);
+ int (*init)(struct qcom_pcie *pcie);
+ void (*deinit)(struct qcom_pcie *pcie);
+};
+
+struct qcom_pcie {
+ struct pcie_port pp;
+ struct device *dev;
+ union qcom_pcie_resources res;
+ void __iomem *parf;
+ void __iomem *dbi;
+ void __iomem *elbi;
+ struct phy *phy;
+ struct gpio_desc *reset;
+ struct qcom_pcie_ops *ops;
+};
+
+#define to_qcom_pcie(x) container_of(x, struct qcom_pcie, pp)
+
+static void qcom_ep_reset_assert(struct qcom_pcie *pcie)
+{
+ gpiod_set_value(pcie->reset, 1);
+ usleep_range(PERST_DELAY_US, PERST_DELAY_US + 500);
+}
+
+static void qcom_ep_reset_deassert(struct qcom_pcie *pcie)
+{
+ gpiod_set_value(pcie->reset, 0);
+ usleep_range(PERST_DELAY_US, PERST_DELAY_US + 500);
+}
+
+static irqreturn_t qcom_pcie_msi_irq_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+
+ return dw_handle_msi_irq(pp);
+}
+
+static int qcom_pcie_enable_link_training(struct qcom_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ u32 val;
+ int ret;
+
+ /* enable link training */
+ val = readl(pcie->elbi + PCIE20_ELBI_SYS_CTRL);
+ val |= PCIE20_ELBI_SYS_CTRL_LT_ENABLE;
+ writel(val, pcie->elbi + PCIE20_ELBI_SYS_CTRL);
+
+ /* wait for up to 100ms for the link to come up */
+ ret = readl_poll_timeout(pcie->elbi + PCIE20_ELBI_SYS_STTS, val,
+ val & XMLH_LINK_UP, LINKUP_DELAY_US,
+ LINKUP_TIMEOUT_US);
+
+ if (ret < 0 || !dw_pcie_link_up(&pcie->pp)) {
+ dev_err(dev, "link initialization failed\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int qcom_pcie_get_resources_v0(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v0 *res = &pcie->res.v0;
+ struct device *dev = pcie->dev;
+
+ res->vdda = devm_regulator_get(dev, "vdda");
+ if (IS_ERR(res->vdda))
+ return PTR_ERR(res->vdda);
+
+ res->vdda_phy = devm_regulator_get(dev, "vdda_phy");
+ if (IS_ERR(res->vdda_phy))
+ return PTR_ERR(res->vdda_phy);
+
+ res->vdda_refclk = devm_regulator_get(dev, "vdda_refclk");
+ if (IS_ERR(res->vdda_refclk))
+ return PTR_ERR(res->vdda_refclk);
+
+ res->iface_clk = devm_clk_get(dev, "iface");
+ if (IS_ERR(res->iface_clk))
+ return PTR_ERR(res->iface_clk);
+
+ res->core_clk = devm_clk_get(dev, "core");
+ if (IS_ERR(res->core_clk))
+ return PTR_ERR(res->core_clk);
+
+ res->phy_clk = devm_clk_get(dev, "phy");
+ if (IS_ERR(res->phy_clk))
+ return PTR_ERR(res->phy_clk);
+
+ res->pci_reset = devm_reset_control_get(dev, "pci");
+ if (IS_ERR(res->pci_reset))
+ return PTR_ERR(res->pci_reset);
+
+ res->axi_reset = devm_reset_control_get(dev, "axi");
+ if (IS_ERR(res->axi_reset))
+ return PTR_ERR(res->axi_reset);
+
+ res->ahb_reset = devm_reset_control_get(dev, "ahb");
+ if (IS_ERR(res->ahb_reset))
+ return PTR_ERR(res->ahb_reset);
+
+ res->por_reset = devm_reset_control_get(dev, "por");
+ if (IS_ERR(res->por_reset))
+ return PTR_ERR(res->por_reset);
+
+ res->phy_reset = devm_reset_control_get(dev, "phy");
+ if (IS_ERR(res->phy_reset))
+ return PTR_ERR(res->phy_reset);
+
+ return 0;
+}
+
+static int qcom_pcie_get_resources_v1(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v1 *res = &pcie->res.v1;
+ struct device *dev = pcie->dev;
+
+ res->vdda = devm_regulator_get(dev, "vdda");
+ if (IS_ERR(res->vdda))
+ return PTR_ERR(res->vdda);
+
+ res->iface = devm_clk_get(dev, "iface");
+ if (IS_ERR(res->iface))
+ return PTR_ERR(res->iface);
+
+ res->aux = devm_clk_get(dev, "aux");
+ if (IS_ERR(res->aux))
+ return PTR_ERR(res->aux);
+
+ res->master_bus = devm_clk_get(dev, "master_bus");
+ if (IS_ERR(res->master_bus))
+ return PTR_ERR(res->master_bus);
+
+ res->slave_bus = devm_clk_get(dev, "slave_bus");
+ if (IS_ERR(res->slave_bus))
+ return PTR_ERR(res->slave_bus);
+
+ res->core = devm_reset_control_get(dev, "core");
+ if (IS_ERR(res->core))
+ return PTR_ERR(res->core);
+
+ return 0;
+}
+
+static void qcom_pcie_deinit_v0(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v0 *res = &pcie->res.v0;
+
+ reset_control_assert(res->pci_reset);
+ reset_control_assert(res->axi_reset);
+ reset_control_assert(res->ahb_reset);
+ reset_control_assert(res->por_reset);
+ reset_control_assert(res->pci_reset);
+ clk_disable_unprepare(res->iface_clk);
+ clk_disable_unprepare(res->core_clk);
+ clk_disable_unprepare(res->phy_clk);
+ regulator_disable(res->vdda);
+ regulator_disable(res->vdda_phy);
+ regulator_disable(res->vdda_refclk);
+}
+
+static int qcom_pcie_init_v0(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v0 *res = &pcie->res.v0;
+ struct device *dev = pcie->dev;
+ u32 val;
+ int ret;
+
+ ret = regulator_enable(res->vdda);
+ if (ret) {
+ dev_err(dev, "cannot enable vdda regulator\n");
+ return ret;
+ }
+
+ ret = regulator_enable(res->vdda_refclk);
+ if (ret) {
+ dev_err(dev, "cannot enable vdda_refclk regulator\n");
+ goto err_refclk;
+ }
+
+ ret = regulator_enable(res->vdda_phy);
+ if (ret) {
+ dev_err(dev, "cannot enable vdda_phy regulator\n");
+ goto err_vdda_phy;
+ }
+
+ ret = reset_control_assert(res->ahb_reset);
+ if (ret) {
+ dev_err(dev, "cannot assert ahb reset\n");
+ goto err_assert_ahb;
+ }
+
+ ret = clk_prepare_enable(res->iface_clk);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable iface clock\n");
+ goto err_assert_ahb;
+ }
+
+ ret = clk_prepare_enable(res->phy_clk);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable phy clock\n");
+ goto err_clk_phy;
+ }
+
+ ret = clk_prepare_enable(res->core_clk);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable core clock\n");
+ goto err_clk_core;
+ }
+
+ ret = reset_control_deassert(res->ahb_reset);
+ if (ret) {
+ dev_err(dev, "cannot deassert ahb reset\n");
+ goto err_deassert_ahb;
+ }
+
+ /* enable PCIe clocks and resets */
+ val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
+ val &= ~BIT(0);
+ writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
+ /* enable external reference clock */
+ val = readl(pcie->parf + PCIE20_PARF_PHY_REFCLK);
+ val |= BIT(16);
+ writel(val, pcie->parf + PCIE20_PARF_PHY_REFCLK);
+
+ ret = reset_control_deassert(res->phy_reset);
+ if (ret) {
+ dev_err(dev, "cannot deassert phy reset\n");
+ return ret;
+ }
+
+ ret = reset_control_deassert(res->pci_reset);
+ if (ret) {
+ dev_err(dev, "cannot deassert pci reset\n");
+ return ret;
+ }
+
+ ret = reset_control_deassert(res->por_reset);
+ if (ret) {
+ dev_err(dev, "cannot deassert por reset\n");
+ return ret;
+ }
+
+ ret = reset_control_deassert(res->axi_reset);
+ if (ret) {
+ dev_err(dev, "cannot deassert axi reset\n");
+ return ret;
+ }
+
+ /* wait for clock acquisition */
+ usleep_range(1000, 1500);
+
+ return 0;
+
+err_deassert_ahb:
+ clk_disable_unprepare(res->core_clk);
+err_clk_core:
+ clk_disable_unprepare(res->phy_clk);
+err_clk_phy:
+ clk_disable_unprepare(res->iface_clk);
+err_assert_ahb:
+ regulator_disable(res->vdda_phy);
+err_vdda_phy:
+ regulator_disable(res->vdda_refclk);
+err_refclk:
+ regulator_disable(res->vdda);
+
+ return ret;
+}
+
+static void qcom_pcie_deinit_v1(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v1 *res = &pcie->res.v1;
+
+ reset_control_assert(res->core);
+ clk_disable_unprepare(res->slave_bus);
+ clk_disable_unprepare(res->master_bus);
+ clk_disable_unprepare(res->iface);
+ clk_disable_unprepare(res->aux);
+ regulator_disable(res->vdda);
+}
+
+static int qcom_pcie_init_v1(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_v1 *res = &pcie->res.v1;
+ struct device *dev = pcie->dev;
+ int ret;
+
+ ret = reset_control_deassert(res->core);
+ if (ret) {
+ dev_err(dev, "cannot deassert core reset\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(res->aux);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable aux clock\n");
+ goto err_res;
+ }
+
+ ret = clk_prepare_enable(res->iface);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable iface clock\n");
+ goto err_aux;
+ }
+
+ ret = clk_prepare_enable(res->master_bus);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable master_bus clock\n");
+ goto err_iface;
+ }
+
+ ret = clk_prepare_enable(res->slave_bus);
+ if (ret) {
+ dev_err(dev, "cannot prepare/enable slave_bus clock\n");
+ goto err_master;
+ }
+
+ ret = regulator_enable(res->vdda);
+ if (ret) {
+ dev_err(dev, "cannot enable vdda regulator\n");
+ goto err_slave;
+ }
+
+
+ /* change DBI base address */
+ writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ u32 val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+
+ val |= BIT(31);
+ writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+ }
+
+ return 0;
+err_slave:
+ clk_disable_unprepare(res->slave_bus);
+err_master:
+ clk_disable_unprepare(res->master_bus);
+err_iface:
+ clk_disable_unprepare(res->iface);
+err_aux:
+ clk_disable_unprepare(res->aux);
+err_res:
+ reset_control_assert(res->core);
+
+ return ret;
+}
+
+static int qcom_pcie_link_up(struct pcie_port *pp)
+{
+ struct qcom_pcie *pcie = to_qcom_pcie(pp);
+ u32 val = readl(pcie->dbi + PCIE20_CAP_LINKCTRLSTATUS);
+
+ return !!(val & PCIE20_CAP_LINKCTRLSTATUS_LINK_UP);
+}
+
+static void qcom_pcie_host_init(struct pcie_port *pp)
+{
+ struct qcom_pcie *pcie = to_qcom_pcie(pp);
+ int ret;
+
+ qcom_ep_reset_assert(pcie);
+
+ ret = pcie->ops->init(pcie);
+ if (ret)
+ goto err_deinit;
+
+ ret = phy_power_on(pcie->phy);
+ if (ret)
+ goto err_deinit;
+
+ dw_pcie_setup_rc(pp);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ dw_pcie_msi_init(pp);
+
+ qcom_ep_reset_deassert(pcie);
+
+ ret = qcom_pcie_enable_link_training(pcie);
+ if (ret)
+ goto err;
+
+ return;
+err:
+ qcom_ep_reset_assert(pcie);
+ phy_power_off(pcie->phy);
+err_deinit:
+ pcie->ops->deinit(pcie);
+}
+
+static int
+qcom_pcie_rd_own_conf(struct pcie_port *pp, int where, int size, u32 *val)
+{
+ /* the device class is not reported correctly from the register */
+ if (where == PCI_CLASS_REVISION && size == 4) {
+ *val = readl(pp->dbi_base + PCI_CLASS_REVISION);
+ *val &= 0xff; /* keep revision id */
+ *val |= PCI_CLASS_BRIDGE_PCI << 16;
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ return dw_pcie_cfg_read(pp->dbi_base + where, size, val);
+}
+
+static struct pcie_host_ops qcom_pcie_dw_ops = {
+ .link_up = qcom_pcie_link_up,
+ .host_init = qcom_pcie_host_init,
+ .rd_own_conf = qcom_pcie_rd_own_conf,
+};
+
+static const struct qcom_pcie_ops ops_v0 = {
+ .get_resources = qcom_pcie_get_resources_v0,
+ .init = qcom_pcie_init_v0,
+ .deinit = qcom_pcie_deinit_v0,
+};
+
+static const struct qcom_pcie_ops ops_v1 = {
+ .get_resources = qcom_pcie_get_resources_v1,
+ .init = qcom_pcie_init_v1,
+ .deinit = qcom_pcie_deinit_v1,
+};
+
+static int qcom_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct qcom_pcie *pcie;
+ struct pcie_port *pp;
+ int ret;
+
+ pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+ if (!pcie)
+ return -ENOMEM;
+
+ pcie->ops = (struct qcom_pcie_ops *)of_device_get_match_data(dev);
+ pcie->dev = dev;
+
+ pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_LOW);
+ if (IS_ERR(pcie->reset))
+ return PTR_ERR(pcie->reset);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "parf");
+ pcie->parf = devm_ioremap_resource(dev, res);
+ if (IS_ERR(pcie->parf))
+ return PTR_ERR(pcie->parf);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ pcie->dbi = devm_ioremap_resource(dev, res);
+ if (IS_ERR(pcie->dbi))
+ return PTR_ERR(pcie->dbi);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
+ pcie->elbi = devm_ioremap_resource(dev, res);
+ if (IS_ERR(pcie->elbi))
+ return PTR_ERR(pcie->elbi);
+
+ pcie->phy = devm_phy_optional_get(dev, "pciephy");
+ if (IS_ERR(pcie->phy))
+ return PTR_ERR(pcie->phy);
+
+ ret = pcie->ops->get_resources(pcie);
+ if (ret)
+ return ret;
+
+ pp = &pcie->pp;
+ pp->dev = dev;
+ pp->dbi_base = pcie->dbi;
+ pp->root_bus_nr = -1;
+ pp->ops = &qcom_pcie_dw_ops;
+
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ pp->msi_irq = platform_get_irq_byname(pdev, "msi");
+ if (pp->msi_irq < 0)
+ return pp->msi_irq;
+
+ ret = devm_request_irq(dev, pp->msi_irq,
+ qcom_pcie_msi_irq_handler,
+ IRQF_SHARED, "qcom-pcie-msi", pp);
+ if (ret) {
+ dev_err(dev, "cannot request msi irq\n");
+ return ret;
+ }
+ }
+
+ ret = phy_init(pcie->phy);
+ if (ret)
+ return ret;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(dev, "cannot initialize host\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, pcie);
+
+ return 0;
+}
+
+static int qcom_pcie_remove(struct platform_device *pdev)
+{
+ struct qcom_pcie *pcie = platform_get_drvdata(pdev);
+
+ qcom_ep_reset_assert(pcie);
+ phy_power_off(pcie->phy);
+ phy_exit(pcie->phy);
+ pcie->ops->deinit(pcie);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_pcie_match[] = {
+ { .compatible = "qcom,pcie-ipq8064", .data = &ops_v0 },
+ { .compatible = "qcom,pcie-apq8064", .data = &ops_v0 },
+ { .compatible = "qcom,pcie-apq8084", .data = &ops_v1 },
+ { }
+};
+MODULE_DEVICE_TABLE(of, qcom_pcie_match);
+
+static struct platform_driver qcom_pcie_driver = {
+ .probe = qcom_pcie_probe,
+ .remove = qcom_pcie_remove,
+ .driver = {
+ .name = "qcom-pcie",
+ .of_match_table = qcom_pcie_match,
+ },
+};
+
+module_platform_driver(qcom_pcie_driver);
+
+MODULE_AUTHOR("Stanimir Varbanov <svarbanov@mm-sol.com>");
+MODULE_DESCRIPTION("Qualcomm PCIe root complex driver");
+MODULE_LICENSE("GPL v2");
projects / karo-tx-linux.git / commitdiff