diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-spear13xx.c')
-rw-r--r-- | drivers/pci/controller/dwc/pcie-spear13xx.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-spear13xx.c b/drivers/pci/controller/dwc/pcie-spear13xx.c new file mode 100644 index 000000000..e348225f6 --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-spear13xx.c @@ -0,0 +1,284 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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> + */ + +#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 dw_pcie *pci; + void __iomem *app_base; + struct phy *phy; + struct clk *clk; +}; + +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 to_spear13xx_pcie(x) dev_get_drvdata((x)->dev) + +static int spear13xx_pcie_establish_link(struct spear13xx_pcie *spear13xx_pcie) +{ + struct dw_pcie *pci = spear13xx_pcie->pci; + struct pcie_port *pp = &pci->pp; + struct pcie_app_reg *app_reg = spear13xx_pcie->app_base; + u32 val; + u32 exp_cap_off = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); + + if (dw_pcie_link_up(pci)) { + dev_err(pci->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. + */ + val = dw_pcie_readw_dbi(pci, exp_cap_off + PCI_EXP_DEVCTL); + val &= ~PCI_EXP_DEVCTL_READRQ; + dw_pcie_writew_dbi(pci, exp_cap_off + PCI_EXP_DEVCTL, val); + + dw_pcie_writew_dbi(pci, PCI_VENDOR_ID, 0x104A); + dw_pcie_writew_dbi(pci, PCI_DEVICE_ID, 0xCD80); + + /* 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(pci); +} + +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 dw_pcie *pci = spear13xx_pcie->pci; + struct pcie_port *pp = &pci->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 dw_pcie *pci = spear13xx_pcie->pci; + struct pcie_port *pp = &pci->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 dw_pcie *pci) +{ + struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci); + 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 int spear13xx_pcie_host_init(struct pcie_port *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci); + + spear13xx_pcie_establish_link(spear13xx_pcie); + spear13xx_pcie_enable_interrupts(spear13xx_pcie); + + return 0; +} + +static const struct dw_pcie_host_ops spear13xx_pcie_host_ops = { + .host_init = spear13xx_pcie_host_init, +}; + +static int spear13xx_add_pcie_port(struct spear13xx_pcie *spear13xx_pcie, + struct platform_device *pdev) +{ + struct dw_pcie *pci = spear13xx_pcie->pci; + struct pcie_port *pp = &pci->pp; + struct device *dev = &pdev->dev; + int ret; + + pp->irq = platform_get_irq(pdev, 0); + if (pp->irq < 0) + return pp->irq; + + 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->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 const struct dw_pcie_ops dw_pcie_ops = { + .link_up = spear13xx_pcie_link_up, +}; + +static int spear13xx_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dw_pcie *pci; + struct spear13xx_pcie *spear13xx_pcie; + 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; + + pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); + if (!pci) + return -ENOMEM; + + pci->dev = dev; + pci->ops = &dw_pcie_ops; + + spear13xx_pcie->pci = pci; + + 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; + } + + dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi"); + pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base); + if (IS_ERR(pci->dbi_base)) { + ret = PTR_ERR(pci->dbi_base); + goto fail_clk; + } + spear13xx_pcie->app_base = pci->dbi_base + 0x2000; + + if (of_property_read_bool(np, "st,pcie-is-gen1")) + pci->link_gen = 1; + + platform_set_drvdata(pdev, spear13xx_pcie); + + ret = spear13xx_add_pcie_port(spear13xx_pcie, pdev); + if (ret < 0) + goto fail_clk; + + 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), + .suppress_bind_attrs = true, + }, +}; + +builtin_platform_driver(spear13xx_pcie_driver); |