drivers/pci/controller/pci-host-common.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Generic PCI host driver common code
   4  *
   5  * Copyright (C) 2014 ARM Limited
   6  *
   7  * Author: Will Deacon <will.deacon@arm.com>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/of_address.h>
  14 #include <linux/of_pci.h>
  15 #include <linux/pci-ecam.h>
  16 #include <linux/platform_device.h>
  17
  18 static void gen_pci_unmap_cfg(void *ptr)
  19 {
  20         pci_ecam_free((struct pci_config_window *)ptr);
  21 }
  22
  23 static struct pci_config_window *gen_pci_init(struct device *dev,
  24                 struct pci_host_bridge *bridge, const struct pci_ecam_ops *ops)
  25 {
  26         int err;
  27         struct resource cfgres;
  28         struct resource_entry *bus;
  29         struct pci_config_window *cfg;
  30
  31         err = of_address_to_resource(dev->of_node, 0, &cfgres);
  32         if (err) {
  33                 dev_err(dev, "missing \"reg\" property\n");
  34                 return ERR_PTR(err);
  35         }
  36
  37         bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
  38         if (!bus)
  39                 return ERR_PTR(-ENODEV);
  40
  41         cfg = pci_ecam_create(dev, &cfgres, bus->res, ops);
  42         if (IS_ERR(cfg))
  43                 return cfg;
  44
  45         err = devm_add_action_or_reset(dev, gen_pci_unmap_cfg, cfg);
  46         if (err)
  47                 return ERR_PTR(err);
  48
  49         return cfg;
  50 }
  51
  52 int pci_host_common_probe(struct platform_device *pdev)
  53 {
  54         struct device *dev = &pdev->dev;
  55         struct pci_host_bridge *bridge;
  56         struct pci_config_window *cfg;
  57         const struct pci_ecam_ops *ops;
  58
  59         ops = of_device_get_match_data(&pdev->dev);
  60         if (!ops)
  61                 return -ENODEV;
  62
  63         bridge = devm_pci_alloc_host_bridge(dev, 0);
  64         if (!bridge)
  65                 return -ENOMEM;
  66
  67         platform_set_drvdata(pdev, bridge);
  68
  69         of_pci_check_probe_only();
  70
  71         /* Parse and map our Configuration Space windows */
  72         cfg = gen_pci_init(dev, bridge, ops);
  73         if (IS_ERR(cfg))
  74                 return PTR_ERR(cfg);
  75
  76         bridge->sysdata = cfg;
  77         bridge->ops = (struct pci_ops *)&ops->pci_ops;
  78         bridge->msi_domain = true;
  79
  80         return pci_host_probe(bridge);
  81 }
  82 EXPORT_SYMBOL_GPL(pci_host_common_probe);
  83
  84 void pci_host_common_remove(struct platform_device *pdev)
  85 {
  86         struct pci_host_bridge *bridge = platform_get_drvdata(pdev);
  87
  88         pci_lock_rescan_remove();
  89         pci_stop_root_bus(bridge->bus);
  90         pci_remove_root_bus(bridge->bus);
  91         pci_unlock_rescan_remove();
  92 }
  93 EXPORT_SYMBOL_GPL(pci_host_common_remove);
  94
  95 MODULE_DESCRIPTION("Generic PCI host common driver");
  96 MODULE_LICENSE("GPL v2");