1 /* 2 * Code borrowed from powerpc/kernel/pci-common.c 3 * 4 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM 5 * Copyright (C) 2014 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * version 2 as published by the Free Software Foundation. 10 * 11 */ 12 13 #include <linux/acpi.h> 14 #include <linux/init.h> 15 #include <linux/io.h> 16 #include <linux/kernel.h> 17 #include <linux/mm.h> 18 #include <linux/of_pci.h> 19 #include <linux/of_platform.h> 20 #include <linux/pci.h> 21 #include <linux/pci-acpi.h> 22 #include <linux/pci-ecam.h> 23 #include <linux/slab.h> 24 25 /* 26 * Called after each bus is probed, but before its children are examined 27 */ 28 void pcibios_fixup_bus(struct pci_bus *bus) 29 { 30 /* nothing to do, expected to be removed in the future */ 31 } 32 33 /* 34 * We don't have to worry about legacy ISA devices, so nothing to do here 35 */ 36 resource_size_t pcibios_align_resource(void *data, const struct resource *res, 37 resource_size_t size, resource_size_t align) 38 { 39 return res->start; 40 } 41 42 /* 43 * Try to assign the IRQ number when probing a new device 44 */ 45 int pcibios_alloc_irq(struct pci_dev *dev) 46 { 47 if (acpi_disabled) 48 dev->irq = of_irq_parse_and_map_pci(dev, 0, 0); 49 #ifdef CONFIG_ACPI 50 else 51 return acpi_pci_irq_enable(dev); 52 #endif 53 54 return 0; 55 } 56 57 /* 58 * raw_pci_read/write - Platform-specific PCI config space access. 59 */ 60 int raw_pci_read(unsigned int domain, unsigned int bus, 61 unsigned int devfn, int reg, int len, u32 *val) 62 { 63 struct pci_bus *b = pci_find_bus(domain, bus); 64 65 if (!b) 66 return PCIBIOS_DEVICE_NOT_FOUND; 67 return b->ops->read(b, devfn, reg, len, val); 68 } 69 70 int raw_pci_write(unsigned int domain, unsigned int bus, 71 unsigned int devfn, int reg, int len, u32 val) 72 { 73 struct pci_bus *b = pci_find_bus(domain, bus); 74 75 if (!b) 76 return PCIBIOS_DEVICE_NOT_FOUND; 77 return b->ops->write(b, devfn, reg, len, val); 78 } 79 80 #ifdef CONFIG_NUMA 81 82 int pcibus_to_node(struct pci_bus *bus) 83 { 84 return dev_to_node(&bus->dev); 85 } 86 EXPORT_SYMBOL(pcibus_to_node); 87 88 #endif 89 90 #ifdef CONFIG_ACPI 91 92 struct acpi_pci_generic_root_info { 93 struct acpi_pci_root_info common; 94 struct pci_config_window *cfg; /* config space mapping */ 95 }; 96 97 int acpi_pci_bus_find_domain_nr(struct pci_bus *bus) 98 { 99 struct pci_config_window *cfg = bus->sysdata; 100 struct acpi_device *adev = to_acpi_device(cfg->parent); 101 struct acpi_pci_root *root = acpi_driver_data(adev); 102 103 return root->segment; 104 } 105 106 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) 107 { 108 if (!acpi_disabled) { 109 struct pci_config_window *cfg = bridge->bus->sysdata; 110 struct acpi_device *adev = to_acpi_device(cfg->parent); 111 ACPI_COMPANION_SET(&bridge->dev, adev); 112 } 113 114 return 0; 115 } 116 117 /* 118 * Lookup the bus range for the domain in MCFG, and set up config space 119 * mapping. 120 */ 121 static struct pci_config_window * 122 pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root) 123 { 124 struct resource *bus_res = &root->secondary; 125 u16 seg = root->segment; 126 struct pci_config_window *cfg; 127 struct resource cfgres; 128 unsigned int bsz; 129 130 /* Use address from _CBA if present, otherwise lookup MCFG */ 131 if (!root->mcfg_addr) 132 root->mcfg_addr = pci_mcfg_lookup(seg, bus_res); 133 134 if (!root->mcfg_addr) { 135 dev_err(&root->device->dev, "%04x:%pR ECAM region not found\n", 136 seg, bus_res); 137 return NULL; 138 } 139 140 bsz = 1 << pci_generic_ecam_ops.bus_shift; 141 cfgres.start = root->mcfg_addr + bus_res->start * bsz; 142 cfgres.end = cfgres.start + resource_size(bus_res) * bsz - 1; 143 cfgres.flags = IORESOURCE_MEM; 144 cfg = pci_ecam_create(&root->device->dev, &cfgres, bus_res, 145 &pci_generic_ecam_ops); 146 if (IS_ERR(cfg)) { 147 dev_err(&root->device->dev, "%04x:%pR error %ld mapping ECAM\n", 148 seg, bus_res, PTR_ERR(cfg)); 149 return NULL; 150 } 151 152 return cfg; 153 } 154 155 /* release_info: free resources allocated by init_info */ 156 static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) 157 { 158 struct acpi_pci_generic_root_info *ri; 159 160 ri = container_of(ci, struct acpi_pci_generic_root_info, common); 161 pci_ecam_free(ri->cfg); 162 kfree(ri); 163 } 164 165 static struct acpi_pci_root_ops acpi_pci_root_ops = { 166 .release_info = pci_acpi_generic_release_info, 167 }; 168 169 /* Interface called from ACPI code to setup PCI host controller */ 170 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) 171 { 172 int node = acpi_get_node(root->device->handle); 173 struct acpi_pci_generic_root_info *ri; 174 struct pci_bus *bus, *child; 175 176 ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); 177 if (!ri) 178 return NULL; 179 180 ri->cfg = pci_acpi_setup_ecam_mapping(root); 181 if (!ri->cfg) { 182 kfree(ri); 183 return NULL; 184 } 185 186 acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; 187 bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common, 188 ri->cfg); 189 if (!bus) 190 return NULL; 191 192 pci_bus_size_bridges(bus); 193 pci_bus_assign_resources(bus); 194 195 list_for_each_entry(child, &bus->children, node) 196 pcie_bus_configure_settings(child); 197 198 return bus; 199 } 200 201 void pcibios_add_bus(struct pci_bus *bus) 202 { 203 acpi_pci_add_bus(bus); 204 } 205 206 void pcibios_remove_bus(struct pci_bus *bus) 207 { 208 acpi_pci_remove_bus(bus); 209 } 210 211 #endif 212