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/of_address.h>
  12 #include <linux/of_pci.h>
  13 #include <linux/pci-ecam.h>
  14 #include <linux/platform_device.h>
  15
  16 static void gen_pci_unmap_cfg(void *ptr)
  17 {
  18         pci_ecam_free((struct pci_config_window *)ptr);
  19 }
  20
  21 static struct pci_config_window *gen_pci_init(struct device *dev,
  22                 struct list_head *resources, struct pci_ecam_ops *ops)
  23 {
  24         int err;
  25         struct resource cfgres;
  26         struct resource *bus_range = NULL;
  27         struct pci_config_window *cfg;
  28
  29         /* Parse our PCI ranges and request their resources */
  30         err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
  31         if (err)
  32                 return ERR_PTR(err);
  33
  34         err = of_address_to_resource(dev->of_node, 0, &cfgres);
  35         if (err) {
  36                 dev_err(dev, "missing \"reg\" property\n");
  37                 goto err_out;
  38         }
  39
  40         cfg = pci_ecam_create(dev, &cfgres, bus_range, ops);
  41         if (IS_ERR(cfg)) {
  42                 err = PTR_ERR(cfg);
  43                 goto err_out;
  44         }
  45
  46         err = devm_add_action(dev, gen_pci_unmap_cfg, cfg);
  47         if (err) {
  48                 gen_pci_unmap_cfg(cfg);
  49                 goto err_out;
  50         }
  51         return cfg;
  52
  53 err_out:
  54         pci_free_resource_list(resources);
  55         return ERR_PTR(err);
  56 }
  57
  58 int pci_host_common_probe(struct platform_device *pdev,
  59                           struct pci_ecam_ops *ops)
  60 {
  61         struct device *dev = &pdev->dev;
  62         struct pci_host_bridge *bridge;
  63         struct pci_config_window *cfg;
  64         struct list_head resources;
  65         int ret;
  66
  67         bridge = devm_pci_alloc_host_bridge(dev, 0);
  68         if (!bridge)
  69                 return -ENOMEM;
  70
  71         of_pci_check_probe_only();
  72
  73         /* Parse and map our Configuration Space windows */
  74         cfg = gen_pci_init(dev, &resources, ops);
  75         if (IS_ERR(cfg))
  76                 return PTR_ERR(cfg);
  77
  78         /* Do not reassign resources if probe only */
  79         if (!pci_has_flag(PCI_PROBE_ONLY))
  80                 pci_add_flags(PCI_REASSIGN_ALL_BUS);
  81
  82         list_splice_init(&resources, &bridge->windows);
  83         bridge->dev.parent = dev;
  84         bridge->sysdata = cfg;
  85         bridge->busnr = cfg->busr.start;
  86         bridge->ops = &ops->pci_ops;
  87         bridge->map_irq = of_irq_parse_and_map_pci;
  88         bridge->swizzle_irq = pci_common_swizzle;
  89
  90         ret = pci_host_probe(bridge);
  91         if (ret < 0) {
  92                 pci_free_resource_list(&resources);
  93                 return ret;
  94         }
  95
  96         platform_set_drvdata(pdev, bridge->bus);
  97         return 0;
  98 }
  99
 100 int pci_host_common_remove(struct platform_device *pdev)
 101 {
 102         struct pci_bus *bus = platform_get_drvdata(pdev);
 103
 104         pci_lock_rescan_remove();
 105         pci_stop_root_bus(bus);
 106         pci_remove_root_bus(bus);
 107         pci_unlock_rescan_remove();
 108
 109         return 0;
 110 }