| /* |
| * PCIe host controller driver for Texas Instruments Keystone SoCs |
| * |
| * Copyright (C) 2013-2014 Texas Instruments., Ltd. |
| * http://www.ti.com |
| * |
| * Author: Murali Karicheri <m-karicheri2@ti.com> |
| * Implementation based on pci-exynos.c and pcie-designware.c |
| * |
| * 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. |
| */ |
| |
| #include <linux/irqchip/chained_irq.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/irqdomain.h> |
| #include <linux/module.h> |
| #include <linux/msi.h> |
| #include <linux/of_irq.h> |
| #include <linux/of.h> |
| #include <linux/of_pci.h> |
| #include <linux/platform_device.h> |
| #include <linux/phy/phy.h> |
| #include <linux/resource.h> |
| #include <linux/signal.h> |
| |
| #include "pcie-designware.h" |
| #include "pci-keystone.h" |
| |
| #define DRIVER_NAME "keystone-pcie" |
| |
| /* driver specific constants */ |
| #define MAX_MSI_HOST_IRQS 8 |
| #define MAX_LEGACY_HOST_IRQS 4 |
| |
| /* DEV_STAT_CTRL */ |
| #define PCIE_CAP_BASE 0x70 |
| |
| /* PCIE controller device IDs */ |
| #define PCIE_RC_K2HK 0xb008 |
| #define PCIE_RC_K2E 0xb009 |
| #define PCIE_RC_K2L 0xb00a |
| |
| #define to_keystone_pcie(x) container_of(x, struct keystone_pcie, pp) |
| |
| static void quirk_limit_mrrs(struct pci_dev *dev) |
| { |
| struct pci_bus *bus = dev->bus; |
| struct pci_dev *bridge = bus->self; |
| static const struct pci_device_id rc_pci_devids[] = { |
| { PCI_DEVICE(PCI_VENDOR_ID_TI, PCIE_RC_K2HK), |
| .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, |
| { PCI_DEVICE(PCI_VENDOR_ID_TI, PCIE_RC_K2E), |
| .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, |
| { PCI_DEVICE(PCI_VENDOR_ID_TI, PCIE_RC_K2L), |
| .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, |
| { 0, }, |
| }; |
| |
| if (pci_is_root_bus(bus)) |
| return; |
| |
| /* look for the host bridge */ |
| while (!pci_is_root_bus(bus)) { |
| bridge = bus->self; |
| bus = bus->parent; |
| } |
| |
| if (bridge) { |
| /* |
| * Keystone PCI controller has a h/w limitation of |
| * 256 bytes maximum read request size. It can't handle |
| * anything higher than this. So force this limit on |
| * all downstream devices. |
| */ |
| if (pci_match_id(rc_pci_devids, bridge)) { |
| if (pcie_get_readrq(dev) > 256) { |
| dev_info(&dev->dev, "limiting MRRS to 256\n"); |
| pcie_set_readrq(dev, 256); |
| } |
| } |
| } |
| } |
| DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_mrrs); |
| |
| static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie) |
| { |
| struct pcie_port *pp = &ks_pcie->pp; |
| unsigned int retries; |
| |
| dw_pcie_setup_rc(pp); |
| |
| if (dw_pcie_link_up(pp)) { |
| dev_err(pp->dev, "Link already up\n"); |
| return 0; |
| } |
| |
| ks_dw_pcie_initiate_link_train(ks_pcie); |
| /* check if the link is up or not */ |
| for (retries = 0; retries < 200; retries++) { |
| if (dw_pcie_link_up(pp)) |
| return 0; |
| usleep_range(100, 1000); |
| ks_dw_pcie_initiate_link_train(ks_pcie); |
| } |
| |
| dev_err(pp->dev, "phy link never came up\n"); |
| return -EINVAL; |
| } |
| |
| static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc *desc) |
| { |
| struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc); |
| u32 offset = irq - ks_pcie->msi_host_irqs[0]; |
| struct pcie_port *pp = &ks_pcie->pp; |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| |
| dev_dbg(pp->dev, "%s, irq %d\n", __func__, irq); |
| |
| /* |
| * The chained irq handler installation would have replaced normal |
| * interrupt driver handler so we need to take care of mask/unmask and |
| * ack operation. |
| */ |
| chained_irq_enter(chip, desc); |
| ks_dw_pcie_handle_msi_irq(ks_pcie, offset); |
| chained_irq_exit(chip, desc); |
| } |
| |
| /** |
| * ks_pcie_legacy_irq_handler() - Handle legacy interrupt |
| * @irq: IRQ line for legacy interrupts |
| * @desc: Pointer to irq descriptor |
| * |
| * Traverse through pending legacy interrupts and invoke handler for each. Also |
| * takes care of interrupt controller level mask/ack operation. |
| */ |
| static void ks_pcie_legacy_irq_handler(unsigned int irq, struct irq_desc *desc) |
| { |
| struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc); |
| struct pcie_port *pp = &ks_pcie->pp; |
| u32 irq_offset = irq - ks_pcie->legacy_host_irqs[0]; |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| |
| dev_dbg(pp->dev, ": Handling legacy irq %d\n", irq); |
| |
| /* |
| * The chained irq handler installation would have replaced normal |
| * interrupt driver handler so we need to take care of mask/unmask and |
| * ack operation. |
| */ |
| chained_irq_enter(chip, desc); |
| ks_dw_pcie_handle_legacy_irq(ks_pcie, irq_offset); |
| chained_irq_exit(chip, desc); |
| } |
| |
| static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie, |
| char *controller, int *num_irqs) |
| { |
| int temp, max_host_irqs, legacy = 1, *host_irqs, ret = -EINVAL; |
| struct device *dev = ks_pcie->pp.dev; |
| struct device_node *np_pcie = dev->of_node, **np_temp; |
| |
| if (!strcmp(controller, "msi-interrupt-controller")) |
| legacy = 0; |
| |
| if (legacy) { |
| np_temp = &ks_pcie->legacy_intc_np; |
| max_host_irqs = MAX_LEGACY_HOST_IRQS; |
| host_irqs = &ks_pcie->legacy_host_irqs[0]; |
| } else { |
| np_temp = &ks_pcie->msi_intc_np; |
| max_host_irqs = MAX_MSI_HOST_IRQS; |
| host_irqs = &ks_pcie->msi_host_irqs[0]; |
| } |
| |
| /* interrupt controller is in a child node */ |
| *np_temp = of_find_node_by_name(np_pcie, controller); |
| if (!(*np_temp)) { |
| dev_err(dev, "Node for %s is absent\n", controller); |
| goto out; |
| } |
| temp = of_irq_count(*np_temp); |
| if (!temp) |
| goto out; |
| if (temp > max_host_irqs) |
| dev_warn(dev, "Too many %s interrupts defined %u\n", |
| (legacy ? "legacy" : "MSI"), temp); |
| |
| /* |
| * support upto max_host_irqs. In dt from index 0 to 3 (legacy) or 0 to |
| * 7 (MSI) |
| */ |
| for (temp = 0; temp < max_host_irqs; temp++) { |
| host_irqs[temp] = irq_of_parse_and_map(*np_temp, temp); |
| if (!host_irqs[temp]) |
| break; |
| } |
| if (temp) { |
| *num_irqs = temp; |
| ret = 0; |
| } |
| out: |
| return ret; |
| } |
| |
| static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie) |
| { |
| int i; |
| |
| /* Legacy IRQ */ |
| for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) { |
| irq_set_handler_data(ks_pcie->legacy_host_irqs[i], ks_pcie); |
| irq_set_chained_handler(ks_pcie->legacy_host_irqs[i], |
| ks_pcie_legacy_irq_handler); |
| } |
| ks_dw_pcie_enable_legacy_irqs(ks_pcie); |
| |
| /* MSI IRQ */ |
| if (IS_ENABLED(CONFIG_PCI_MSI)) { |
| for (i = 0; i < ks_pcie->num_msi_host_irqs; i++) { |
| irq_set_chained_handler_and_data(ks_pcie->msi_host_irqs[i], |
| ks_pcie_msi_irq_handler, |
| ks_pcie); |
| } |
| } |
| } |
| |
| /* |
| * When a PCI device does not exist during config cycles, keystone host gets a |
| * bus error instead of returning 0xffffffff. This handler always returns 0 |
| * for this kind of faults. |
| */ |
| static int keystone_pcie_fault(unsigned long addr, unsigned int fsr, |
| struct pt_regs *regs) |
| { |
| unsigned long instr = *(unsigned long *) instruction_pointer(regs); |
| |
| if ((instr & 0x0e100090) == 0x00100090) { |
| int reg = (instr >> 12) & 15; |
| |
| regs->uregs[reg] = -1; |
| regs->ARM_pc += 4; |
| } |
| |
| return 0; |
| } |
| |
| static void __init ks_pcie_host_init(struct pcie_port *pp) |
| { |
| struct keystone_pcie *ks_pcie = to_keystone_pcie(pp); |
| u32 val; |
| |
| ks_pcie_establish_link(ks_pcie); |
| ks_dw_pcie_setup_rc_app_regs(ks_pcie); |
| ks_pcie_setup_interrupts(ks_pcie); |
| writew(PCI_IO_RANGE_TYPE_32 | (PCI_IO_RANGE_TYPE_32 << 8), |
| pp->dbi_base + PCI_IO_BASE); |
| |
| /* update the Vendor ID */ |
| writew(ks_pcie->device_id, pp->dbi_base + PCI_DEVICE_ID); |
| |
| /* update the DEV_STAT_CTRL to publish right mrrs */ |
| val = readl(pp->dbi_base + PCIE_CAP_BASE + PCI_EXP_DEVCTL); |
| val &= ~PCI_EXP_DEVCTL_READRQ; |
| /* set the mrrs to 256 bytes */ |
| val |= BIT(12); |
| writel(val, pp->dbi_base + PCIE_CAP_BASE + PCI_EXP_DEVCTL); |
| |
| /* |
| * PCIe access errors that result into OCP errors are caught by ARM as |
| * "External aborts" |
| */ |
| hook_fault_code(17, keystone_pcie_fault, SIGBUS, 0, |
| "Asynchronous external abort"); |
| } |
| |
| static struct pcie_host_ops keystone_pcie_host_ops = { |
| .rd_other_conf = ks_dw_pcie_rd_other_conf, |
| .wr_other_conf = ks_dw_pcie_wr_other_conf, |
| .link_up = ks_dw_pcie_link_up, |
| .host_init = ks_pcie_host_init, |
| .msi_set_irq = ks_dw_pcie_msi_set_irq, |
| .msi_clear_irq = ks_dw_pcie_msi_clear_irq, |
| .get_msi_addr = ks_dw_pcie_get_msi_addr, |
| .msi_host_init = ks_dw_pcie_msi_host_init, |
| .scan_bus = ks_dw_pcie_v3_65_scan_bus, |
| }; |
| |
| static int __init ks_add_pcie_port(struct keystone_pcie *ks_pcie, |
| struct platform_device *pdev) |
| { |
| struct pcie_port *pp = &ks_pcie->pp; |
| int ret; |
| |
| ret = ks_pcie_get_irq_controller_info(ks_pcie, |
| "legacy-interrupt-controller", |
| &ks_pcie->num_legacy_host_irqs); |
| if (ret) |
| return ret; |
| |
| if (IS_ENABLED(CONFIG_PCI_MSI)) { |
| ret = ks_pcie_get_irq_controller_info(ks_pcie, |
| "msi-interrupt-controller", |
| &ks_pcie->num_msi_host_irqs); |
| if (ret) |
| return ret; |
| } |
| |
| pp->root_bus_nr = -1; |
| pp->ops = &keystone_pcie_host_ops; |
| ret = ks_dw_pcie_host_init(ks_pcie, ks_pcie->msi_intc_np); |
| if (ret) { |
| dev_err(&pdev->dev, "failed to initialize host\n"); |
| return ret; |
| } |
| |
| return ret; |
| } |
| |
| static const struct of_device_id ks_pcie_of_match[] = { |
| { |
| .type = "pci", |
| .compatible = "ti,keystone-pcie", |
| }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, ks_pcie_of_match); |
| |
| static int __exit ks_pcie_remove(struct platform_device *pdev) |
| { |
| struct keystone_pcie *ks_pcie = platform_get_drvdata(pdev); |
| |
| clk_disable_unprepare(ks_pcie->clk); |
| |
| return 0; |
| } |
| |
| static int __init ks_pcie_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct keystone_pcie *ks_pcie; |
| struct pcie_port *pp; |
| struct resource *res; |
| void __iomem *reg_p; |
| struct phy *phy; |
| int ret = 0; |
| |
| ks_pcie = devm_kzalloc(&pdev->dev, sizeof(*ks_pcie), |
| GFP_KERNEL); |
| if (!ks_pcie) |
| return -ENOMEM; |
| |
| pp = &ks_pcie->pp; |
| |
| /* initialize SerDes Phy if present */ |
| phy = devm_phy_get(dev, "pcie-phy"); |
| if (!IS_ERR_OR_NULL(phy)) { |
| ret = phy_init(phy); |
| if (ret < 0) |
| return ret; |
| } |
| |
| /* index 2 is to read PCI DEVICE_ID */ |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 2); |
| reg_p = devm_ioremap_resource(dev, res); |
| if (IS_ERR(reg_p)) |
| return PTR_ERR(reg_p); |
| ks_pcie->device_id = readl(reg_p) >> 16; |
| devm_iounmap(dev, reg_p); |
| devm_release_mem_region(dev, res->start, resource_size(res)); |
| |
| pp->dev = dev; |
| platform_set_drvdata(pdev, ks_pcie); |
| ks_pcie->clk = devm_clk_get(dev, "pcie"); |
| if (IS_ERR(ks_pcie->clk)) { |
| dev_err(dev, "Failed to get pcie rc clock\n"); |
| return PTR_ERR(ks_pcie->clk); |
| } |
| ret = clk_prepare_enable(ks_pcie->clk); |
| if (ret) |
| return ret; |
| |
| ret = ks_add_pcie_port(ks_pcie, pdev); |
| if (ret < 0) |
| goto fail_clk; |
| |
| return 0; |
| fail_clk: |
| clk_disable_unprepare(ks_pcie->clk); |
| |
| return ret; |
| } |
| |
| static struct platform_driver ks_pcie_driver __refdata = { |
| .probe = ks_pcie_probe, |
| .remove = __exit_p(ks_pcie_remove), |
| .driver = { |
| .name = "keystone-pcie", |
| .of_match_table = of_match_ptr(ks_pcie_of_match), |
| }, |
| }; |
| |
| module_platform_driver(ks_pcie_driver); |
| |
| MODULE_AUTHOR("Murali Karicheri <m-karicheri2@ti.com>"); |
| MODULE_DESCRIPTION("Keystone PCIe host controller driver"); |
| MODULE_LICENSE("GPL v2"); |