drivers/pci/host/pcie-designware-plat.c

   1 /*
   2  * PCIe RC driver for Synopsys DesignWare Core
   3  *
   4  * Copyright (C) 2015-2016 Synopsys, Inc. (www.synopsys.com)
   5  *
   6  * Authors: Joao Pinto <Joao.Pinto@synopsys.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12 #include <linux/clk.h>
  13 #include <linux/delay.h>
  14 #include <linux/gpio.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/of_gpio.h>
  19 #include <linux/pci.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/resource.h>
  22 #include <linux/signal.h>
  23 #include <linux/types.h>
  24
  25 #include "pcie-designware.h"
  26
  27 struct dw_plat_pcie {
  28         struct pcie_port        pp;     /* pp.dbi_base is DT 0th resource */
  29 };
  30
  31 static irqreturn_t dw_plat_pcie_msi_irq_handler(int irq, void *arg)
  32 {
  33         struct pcie_port *pp = arg;
  34
  35         return dw_handle_msi_irq(pp);
  36 }
  37
  38 static void dw_plat_pcie_host_init(struct pcie_port *pp)
  39 {
  40         dw_pcie_setup_rc(pp);
  41         dw_pcie_wait_for_link(pp);
  42
  43         if (IS_ENABLED(CONFIG_PCI_MSI))
  44                 dw_pcie_msi_init(pp);
  45 }
  46
  47 static struct pcie_host_ops dw_plat_pcie_host_ops = {
  48         .host_init = dw_plat_pcie_host_init,
  49 };
  50
  51 static int dw_plat_add_pcie_port(struct pcie_port *pp,
  52                                  struct platform_device *pdev)
  53 {
  54         struct device *dev = pp->dev;
  55         int ret;
  56
  57         pp->irq = platform_get_irq(pdev, 1);
  58         if (pp->irq < 0)
  59                 return pp->irq;
  60
  61         if (IS_ENABLED(CONFIG_PCI_MSI)) {
  62                 pp->msi_irq = platform_get_irq(pdev, 0);
  63                 if (pp->msi_irq < 0)
  64                         return pp->msi_irq;
  65
  66                 ret = devm_request_irq(dev, pp->msi_irq,
  67                                         dw_plat_pcie_msi_irq_handler,
  68                                         IRQF_SHARED, "dw-plat-pcie-msi", pp);
  69                 if (ret) {
  70                         dev_err(dev, "failed to request MSI IRQ\n");
  71                         return ret;
  72                 }
  73         }
  74
  75         pp->root_bus_nr = -1;
  76         pp->ops = &dw_plat_pcie_host_ops;
  77
  78         ret = dw_pcie_host_init(pp);
  79         if (ret) {
  80                 dev_err(dev, "failed to initialize host\n");
  81                 return ret;
  82         }
  83
  84         return 0;
  85 }
  86
  87 static int dw_plat_pcie_probe(struct platform_device *pdev)
  88 {
  89         struct device *dev = &pdev->dev;
  90         struct dw_plat_pcie *dw_plat_pcie;
  91         struct pcie_port *pp;
  92         struct resource *res;  /* Resource from DT */
  93         int ret;
  94
  95         dw_plat_pcie = devm_kzalloc(dev, sizeof(*dw_plat_pcie), GFP_KERNEL);
  96         if (!dw_plat_pcie)
  97                 return -ENOMEM;
  98
  99         pp = &dw_plat_pcie->pp;
 100         pp->dev = dev;
 101
 102         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 103         pp->dbi_base = devm_ioremap_resource(dev, res);
 104         if (IS_ERR(pp->dbi_base))
 105                 return PTR_ERR(pp->dbi_base);
 106
 107         ret = dw_plat_add_pcie_port(pp, pdev);
 108         if (ret < 0)
 109                 return ret;
 110
 111         return 0;
 112 }
 113
 114 static const struct of_device_id dw_plat_pcie_of_match[] = {
 115         { .compatible = "snps,dw-pcie", },
 116         {},
 117 };
 118
 119 static struct platform_driver dw_plat_pcie_driver = {
 120         .driver = {
 121                 .name   = "dw-pcie",
 122                 .of_match_table = dw_plat_pcie_of_match,
 123         },
 124         .probe = dw_plat_pcie_probe,
 125 };
 126 builtin_platform_driver(dw_plat_pcie_driver);