| /* |
| * PCIe host controller driver for ST Microelectronics SPEAr13xx SoCs |
| * |
| * SPEAr13xx PCIe Glue Layer Source Code |
| * |
| * Copyright (C) 2010-2014 ST Microelectronics |
| * Pratyush Anand <pratyush.anand@gmail.com> |
| * Mohit Kumar <mohit.kumar.dhaka@gmail.com> |
| * |
| * This file is licensed under the terms of the GNU General Public |
| * License version 2. This program is licensed "as is" without any |
| * warranty of any kind, whether express or implied. |
| */ |
| |
| #include <linux/clk.h> |
| #include <linux/interrupt.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/of.h> |
| #include <linux/pci.h> |
| #include <linux/phy/phy.h> |
| #include <linux/platform_device.h> |
| #include <linux/resource.h> |
| |
| #include "pcie-designware.h" |
| |
| struct spear13xx_pcie { |
| struct pcie_port pp; /* DT dbi is pp.dbi_base */ |
| void __iomem *app_base; |
| struct phy *phy; |
| struct clk *clk; |
| bool is_gen1; |
| }; |
| |
| struct pcie_app_reg { |
| u32 app_ctrl_0; /* cr0 */ |
| u32 app_ctrl_1; /* cr1 */ |
| u32 app_status_0; /* cr2 */ |
| u32 app_status_1; /* cr3 */ |
| u32 msg_status; /* cr4 */ |
| u32 msg_payload; /* cr5 */ |
| u32 int_sts; /* cr6 */ |
| u32 int_clr; /* cr7 */ |
| u32 int_mask; /* cr8 */ |
| u32 mst_bmisc; /* cr9 */ |
| u32 phy_ctrl; /* cr10 */ |
| u32 phy_status; /* cr11 */ |
| u32 cxpl_debug_info_0; /* cr12 */ |
| u32 cxpl_debug_info_1; /* cr13 */ |
| u32 ven_msg_ctrl_0; /* cr14 */ |
| u32 ven_msg_ctrl_1; /* cr15 */ |
| u32 ven_msg_data_0; /* cr16 */ |
| u32 ven_msg_data_1; /* cr17 */ |
| u32 ven_msi_0; /* cr18 */ |
| u32 ven_msi_1; /* cr19 */ |
| u32 mst_rmisc; /* cr20 */ |
| }; |
| |
| /* CR0 ID */ |
| #define APP_LTSSM_ENABLE_ID 3 |
| #define DEVICE_TYPE_RC (4 << 25) |
| #define MISCTRL_EN_ID 30 |
| #define REG_TRANSLATION_ENABLE 31 |
| |
| /* CR3 ID */ |
| #define XMLH_LINK_UP (1 << 6) |
| |
| /* CR6 */ |
| #define MSI_CTRL_INT (1 << 26) |
| |
| #define EXP_CAP_ID_OFFSET 0x70 |
| |
| #define to_spear13xx_pcie(x) container_of(x, struct spear13xx_pcie, pp) |
| |
| static int spear13xx_pcie_establish_link(struct spear13xx_pcie *spear13xx_pcie) |
| { |
| struct pcie_port *pp = &spear13xx_pcie->pp; |
| struct pcie_app_reg *app_reg = spear13xx_pcie->app_base; |
| u32 val; |
| u32 exp_cap_off = EXP_CAP_ID_OFFSET; |
| |
| if (dw_pcie_link_up(pp)) { |
| dev_err(pp->dev, "link already up\n"); |
| return 0; |
| } |
| |
| dw_pcie_setup_rc(pp); |
| |
| /* |
| * this controller support only 128 bytes read size, however its |
| * default value in capability register is 512 bytes. So force |
| * it to 128 here. |
| */ |
| dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val); |
| val &= ~PCI_EXP_DEVCTL_READRQ; |
| dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val); |
| |
| dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 2, 0x104A); |
| dw_pcie_cfg_write(pp->dbi_base + PCI_DEVICE_ID, 2, 0xCD80); |
| |
| /* |
| * if is_gen1 is set then handle it, so that some buggy card |
| * also works |
| */ |
| if (spear13xx_pcie->is_gen1) { |
| dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCAP, |
| 4, &val); |
| if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) { |
| val &= ~((u32)PCI_EXP_LNKCAP_SLS); |
| val |= PCI_EXP_LNKCAP_SLS_2_5GB; |
| dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + |
| PCI_EXP_LNKCAP, 4, val); |
| } |
| |
| dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2, |
| 2, &val); |
| if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) { |
| val &= ~((u32)PCI_EXP_LNKCAP_SLS); |
| val |= PCI_EXP_LNKCAP_SLS_2_5GB; |
| dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + |
| PCI_EXP_LNKCTL2, 2, val); |
| } |
| } |
| |
| /* enable ltssm */ |
| writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID) |
| | (1 << APP_LTSSM_ENABLE_ID) |
| | ((u32)1 << REG_TRANSLATION_ENABLE), |
| &app_reg->app_ctrl_0); |
| |
| return dw_pcie_wait_for_link(pp); |
| } |
| |
| static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg) |
| { |
| struct spear13xx_pcie *spear13xx_pcie = arg; |
| struct pcie_app_reg *app_reg = spear13xx_pcie->app_base; |
| struct pcie_port *pp = &spear13xx_pcie->pp; |
| unsigned int status; |
| |
| status = readl(&app_reg->int_sts); |
| |
| if (status & MSI_CTRL_INT) { |
| BUG_ON(!IS_ENABLED(CONFIG_PCI_MSI)); |
| dw_handle_msi_irq(pp); |
| } |
| |
| writel(status, &app_reg->int_clr); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void spear13xx_pcie_enable_interrupts(struct spear13xx_pcie *spear13xx_pcie) |
| { |
| struct pcie_port *pp = &spear13xx_pcie->pp; |
| struct pcie_app_reg *app_reg = spear13xx_pcie->app_base; |
| |
| /* Enable MSI interrupt */ |
| if (IS_ENABLED(CONFIG_PCI_MSI)) { |
| dw_pcie_msi_init(pp); |
| writel(readl(&app_reg->int_mask) | |
| MSI_CTRL_INT, &app_reg->int_mask); |
| } |
| } |
| |
| static int spear13xx_pcie_link_up(struct pcie_port *pp) |
| { |
| struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp); |
| struct pcie_app_reg *app_reg = spear13xx_pcie->app_base; |
| |
| if (readl(&app_reg->app_status_1) & XMLH_LINK_UP) |
| return 1; |
| |
| return 0; |
| } |
| |
| static void spear13xx_pcie_host_init(struct pcie_port *pp) |
| { |
| struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp); |
| |
| spear13xx_pcie_establish_link(spear13xx_pcie); |
| spear13xx_pcie_enable_interrupts(spear13xx_pcie); |
| } |
| |
| static struct pcie_host_ops spear13xx_pcie_host_ops = { |
| .link_up = spear13xx_pcie_link_up, |
| .host_init = spear13xx_pcie_host_init, |
| }; |
| |
| static int spear13xx_add_pcie_port(struct spear13xx_pcie *spear13xx_pcie, |
| struct platform_device *pdev) |
| { |
| struct pcie_port *pp = &spear13xx_pcie->pp; |
| struct device *dev = pp->dev; |
| int ret; |
| |
| pp->irq = platform_get_irq(pdev, 0); |
| if (!pp->irq) { |
| dev_err(dev, "failed to get irq\n"); |
| return -ENODEV; |
| } |
| ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler, |
| IRQF_SHARED | IRQF_NO_THREAD, |
| "spear1340-pcie", spear13xx_pcie); |
| if (ret) { |
| dev_err(dev, "failed to request irq %d\n", pp->irq); |
| return ret; |
| } |
| |
| pp->root_bus_nr = -1; |
| pp->ops = &spear13xx_pcie_host_ops; |
| |
| ret = dw_pcie_host_init(pp); |
| if (ret) { |
| dev_err(dev, "failed to initialize host\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int spear13xx_pcie_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct spear13xx_pcie *spear13xx_pcie; |
| struct pcie_port *pp; |
| struct device_node *np = dev->of_node; |
| struct resource *dbi_base; |
| int ret; |
| |
| spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL); |
| if (!spear13xx_pcie) |
| return -ENOMEM; |
| |
| spear13xx_pcie->phy = devm_phy_get(dev, "pcie-phy"); |
| if (IS_ERR(spear13xx_pcie->phy)) { |
| ret = PTR_ERR(spear13xx_pcie->phy); |
| if (ret == -EPROBE_DEFER) |
| dev_info(dev, "probe deferred\n"); |
| else |
| dev_err(dev, "couldn't get pcie-phy\n"); |
| return ret; |
| } |
| |
| phy_init(spear13xx_pcie->phy); |
| |
| spear13xx_pcie->clk = devm_clk_get(dev, NULL); |
| if (IS_ERR(spear13xx_pcie->clk)) { |
| dev_err(dev, "couldn't get clk for pcie\n"); |
| return PTR_ERR(spear13xx_pcie->clk); |
| } |
| ret = clk_prepare_enable(spear13xx_pcie->clk); |
| if (ret) { |
| dev_err(dev, "couldn't enable clk for pcie\n"); |
| return ret; |
| } |
| |
| pp = &spear13xx_pcie->pp; |
| pp->dev = dev; |
| |
| dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi"); |
| pp->dbi_base = devm_ioremap_resource(dev, dbi_base); |
| if (IS_ERR(pp->dbi_base)) { |
| dev_err(dev, "couldn't remap dbi base %p\n", dbi_base); |
| ret = PTR_ERR(pp->dbi_base); |
| goto fail_clk; |
| } |
| spear13xx_pcie->app_base = pp->dbi_base + 0x2000; |
| |
| if (of_property_read_bool(np, "st,pcie-is-gen1")) |
| spear13xx_pcie->is_gen1 = true; |
| |
| ret = spear13xx_add_pcie_port(spear13xx_pcie, pdev); |
| if (ret < 0) |
| goto fail_clk; |
| |
| platform_set_drvdata(pdev, spear13xx_pcie); |
| return 0; |
| |
| fail_clk: |
| clk_disable_unprepare(spear13xx_pcie->clk); |
| |
| return ret; |
| } |
| |
| static const struct of_device_id spear13xx_pcie_of_match[] = { |
| { .compatible = "st,spear1340-pcie", }, |
| {}, |
| }; |
| |
| static struct platform_driver spear13xx_pcie_driver = { |
| .probe = spear13xx_pcie_probe, |
| .driver = { |
| .name = "spear-pcie", |
| .of_match_table = of_match_ptr(spear13xx_pcie_of_match), |
| }, |
| }; |
| |
| static int __init spear13xx_pcie_init(void) |
| { |
| return platform_driver_register(&spear13xx_pcie_driver); |
| } |
| device_initcall(spear13xx_pcie_init); |