arch/powerpc/kernel/pci_32.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Common pmac/prep/chrp pci routines. -- Cort
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/pci.h>
   8 #include <linux/delay.h>
   9 #include <linux/string.h>
  10 #include <linux/init.h>
  11 #include <linux/capability.h>
  12 #include <linux/sched.h>
  13 #include <linux/errno.h>
  14 #include <linux/memblock.h>
  15 #include <linux/syscalls.h>
  16 #include <linux/irq.h>
  17 #include <linux/list.h>
  18 #include <linux/of.h>
  19 #include <linux/slab.h>
  20 #include <linux/export.h>
  21
  22 #include <asm/processor.h>
  23 #include <asm/io.h>
  24 #include <asm/sections.h>
  25 #include <asm/pci-bridge.h>
  26 #include <asm/ppc-pci.h>
  27 #include <asm/byteorder.h>
  28 #include <linux/uaccess.h>
  29 #include <asm/machdep.h>
  30
  31 #undef DEBUG
  32
  33 unsigned long isa_io_base     = 0;
  34 unsigned long pci_dram_offset = 0;
  35 int pcibios_assign_bus_offset = 1;
  36 EXPORT_SYMBOL(isa_io_base);
  37 EXPORT_SYMBOL(pci_dram_offset);
  38
  39 static void fixup_cpc710_pci64(struct pci_dev* dev);
  40
  41 /* By default, we don't re-assign bus numbers. We do this only on
  42  * some pmacs
  43  */
  44 static int pci_assign_all_buses;
  45
  46 /* This will remain NULL for now, until isa-bridge.c is made common
  47  * to both 32-bit and 64-bit.
  48  */
  49 struct pci_dev *isa_bridge_pcidev;
  50 EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
  51
  52 static void
  53 fixup_cpc710_pci64(struct pci_dev* dev)
  54 {
  55         /* Hide the PCI64 BARs from the kernel as their content doesn't
  56          * fit well in the resource management
  57          */
  58         dev->resource[0].start = dev->resource[0].end = 0;
  59         dev->resource[0].flags = 0;
  60         dev->resource[1].start = dev->resource[1].end = 0;
  61         dev->resource[1].flags = 0;
  62 }
  63 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM,     PCI_DEVICE_ID_IBM_CPC710_PCI64, fixup_cpc710_pci64);
  64
  65 #ifdef CONFIG_PPC_PCI_OF_BUS_MAP
  66
  67 static u8* pci_to_OF_bus_map;
  68 static int pci_bus_count;
  69
  70 /*
  71  * Functions below are used on OpenFirmware machines.
  72  */
  73 static void
  74 make_one_node_map(struct device_node* node, u8 pci_bus)
  75 {
  76         const int *bus_range;
  77         int len;
  78
  79         if (pci_bus >= pci_bus_count)
  80                 return;
  81         bus_range = of_get_property(node, "bus-range", &len);
  82         if (bus_range == NULL || len < 2 * sizeof(int)) {
  83                 printk(KERN_WARNING "Can't get bus-range for %pOF, "
  84                        "assuming it starts at 0\n", node);
  85                 pci_to_OF_bus_map[pci_bus] = 0;
  86         } else
  87                 pci_to_OF_bus_map[pci_bus] = bus_range[0];
  88
  89         for_each_child_of_node(node, node) {
  90                 struct pci_dev* dev;
  91                 const unsigned int *class_code, *reg;
  92
  93                 class_code = of_get_property(node, "class-code", NULL);
  94                 if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
  95                         (*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
  96                         continue;
  97                 reg = of_get_property(node, "reg", NULL);
  98                 if (!reg)
  99                         continue;
 100                 dev = pci_get_domain_bus_and_slot(0, pci_bus,
 101                                                   ((reg[0] >> 8) & 0xff));
 102                 if (!dev || !dev->subordinate) {
 103                         pci_dev_put(dev);
 104                         continue;
 105                 }
 106                 make_one_node_map(node, dev->subordinate->number);
 107                 pci_dev_put(dev);
 108         }
 109 }
 110
 111 static void __init
 112 pcibios_make_OF_bus_map(void)
 113 {
 114         int i;
 115         struct pci_controller *hose, *tmp;
 116         struct property *map_prop;
 117         struct device_node *dn;
 118
 119         pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
 120         if (!pci_to_OF_bus_map) {
 121                 printk(KERN_ERR "Can't allocate OF bus map !\n");
 122                 return;
 123         }
 124
 125         /* We fill the bus map with invalid values, that helps
 126          * debugging.
 127          */
 128         for (i=0; i<pci_bus_count; i++)
 129                 pci_to_OF_bus_map[i] = 0xff;
 130
 131         /* For each hose, we begin searching bridges */
 132         list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
 133                 struct device_node* node = hose->dn;
 134
 135                 if (!node)
 136                         continue;
 137                 make_one_node_map(node, hose->first_busno);
 138         }
 139         dn = of_find_node_by_path("/");
 140         map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
 141         if (map_prop) {
 142                 BUG_ON(pci_bus_count > map_prop->length);
 143                 memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
 144         }
 145         of_node_put(dn);
 146 #ifdef DEBUG
 147         printk("PCI->OF bus map:\n");
 148         for (i=0; i<pci_bus_count; i++) {
 149                 if (pci_to_OF_bus_map[i] == 0xff)
 150                         continue;
 151                 printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
 152         }
 153 #endif
 154 }
 155 #endif // CONFIG_PPC_PCI_OF_BUS_MAP
 156
 157
 158 #ifdef CONFIG_PPC_PMAC
 159 /*
 160  * Returns the PCI device matching a given OF node
 161  */
 162 int pci_device_from_OF_node(struct device_node *node, u8 *bus, u8 *devfn)
 163 {
 164 #ifdef CONFIG_PPC_PCI_OF_BUS_MAP
 165         struct pci_dev *dev = NULL;
 166 #endif
 167         const __be32 *reg;
 168         int size;
 169
 170         /* Check if it might have a chance to be a PCI device */
 171         if (!pci_find_hose_for_OF_device(node))
 172                 return -ENODEV;
 173
 174         reg = of_get_property(node, "reg", &size);
 175         if (!reg || size < 5 * sizeof(u32))
 176                 return -ENODEV;
 177
 178         *bus = (be32_to_cpup(&reg[0]) >> 16) & 0xff;
 179         *devfn = (be32_to_cpup(&reg[0]) >> 8) & 0xff;
 180
 181 #ifndef CONFIG_PPC_PCI_OF_BUS_MAP
 182         return 0;
 183 #else
 184         /* Ok, here we need some tweak. If we have already renumbered
 185          * all busses, we can't rely on the OF bus number any more.
 186          * the pci_to_OF_bus_map is not enough as several PCI busses
 187          * may match the same OF bus number.
 188          */
 189         if (!pci_to_OF_bus_map)
 190                 return 0;
 191
 192         for_each_pci_dev(dev)
 193                 if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
 194                                 dev->devfn == *devfn) {
 195                         *bus = dev->bus->number;
 196                         pci_dev_put(dev);
 197                         return 0;
 198                 }
 199
 200         return -ENODEV;
 201 #endif // CONFIG_PPC_PCI_OF_BUS_MAP
 202 }
 203 EXPORT_SYMBOL(pci_device_from_OF_node);
 204 #endif
 205
 206 #ifdef CONFIG_PPC_PCI_OF_BUS_MAP
 207 /* We create the "pci-OF-bus-map" property now so it appears in the
 208  * /proc device tree
 209  */
 210 void __init
 211 pci_create_OF_bus_map(void)
 212 {
 213         struct property* of_prop;
 214         struct device_node *dn;
 215
 216         of_prop = memblock_alloc(sizeof(struct property) + 256,
 217                                  SMP_CACHE_BYTES);
 218         if (!of_prop)
 219                 panic("%s: Failed to allocate %zu bytes\n", __func__,
 220                       sizeof(struct property) + 256);
 221         dn = of_find_node_by_path("/");
 222         if (dn) {
 223                 memset(of_prop, -1, sizeof(struct property) + 256);
 224                 of_prop->name = "pci-OF-bus-map";
 225                 of_prop->length = 256;
 226                 of_prop->value = &of_prop[1];
 227                 of_add_property(dn, of_prop);
 228                 of_node_put(dn);
 229         }
 230 }
 231 #endif // CONFIG_PPC_PCI_OF_BUS_MAP
 232
 233 void pcibios_setup_phb_io_space(struct pci_controller *hose)
 234 {
 235         unsigned long io_offset;
 236         struct resource *res = &hose->io_resource;
 237
 238         /* Fixup IO space offset */
 239         io_offset = pcibios_io_space_offset(hose);
 240         res->start += io_offset;
 241         res->end += io_offset;
 242 }
 243
 244 static int __init pcibios_init(void)
 245 {
 246         struct pci_controller *hose, *tmp;
 247 #ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT
 248         int next_busno = 0;
 249 #endif
 250
 251         printk(KERN_INFO "PCI: Probing PCI hardware\n");
 252
 253 #ifdef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT
 254         /*
 255          * Enable PCI domains in /proc when PCI bus numbers are not unique
 256          * across all PCI domains to prevent conflicts. And keep PCI domain 0
 257          * backward compatible in /proc for video cards.
 258          */
 259         pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0);
 260 #endif
 261
 262         if (pci_has_flag(PCI_REASSIGN_ALL_BUS))
 263                 pci_assign_all_buses = 1;
 264
 265         /* Scan all of the recorded PCI controllers.  */
 266         list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
 267 #ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT
 268                 if (pci_assign_all_buses)
 269                         hose->first_busno = next_busno;
 270 #endif
 271                 hose->last_busno = 0xff;
 272                 pcibios_scan_phb(hose);
 273                 pci_bus_add_devices(hose->bus);
 274 #ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT
 275                 if (pci_assign_all_buses || next_busno <= hose->last_busno)
 276                         next_busno = hose->last_busno + pcibios_assign_bus_offset;
 277 #endif
 278         }
 279
 280 #if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_CHRP)
 281 #ifdef CONFIG_PPC_PCI_OF_BUS_MAP
 282         pci_bus_count = next_busno;
 283
 284         /* OpenFirmware based machines need a map of OF bus
 285          * numbers vs. kernel bus numbers since we may have to
 286          * remap them.
 287          */
 288         if (pci_assign_all_buses)
 289                 pcibios_make_OF_bus_map();
 290 #endif
 291 #endif
 292
 293         /* Call common code to handle resource allocation */
 294         pcibios_resource_survey();
 295
 296         /* Call machine dependent fixup */
 297         if (ppc_md.pcibios_fixup)
 298                 ppc_md.pcibios_fixup();
 299
 300         /* Call machine dependent post-init code */
 301         if (ppc_md.pcibios_after_init)
 302                 ppc_md.pcibios_after_init();
 303
 304         return 0;
 305 }
 306
 307 subsys_initcall(pcibios_init);
 308
 309 static struct pci_controller*
 310 pci_bus_to_hose(int bus)
 311 {
 312         struct pci_controller *hose, *tmp;
 313
 314         list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
 315                 if (bus >= hose->first_busno && bus <= hose->last_busno)
 316                         return hose;
 317         return NULL;
 318 }
 319
 320 /* Provide information on locations of various I/O regions in physical
 321  * memory.  Do this on a per-card basis so that we choose the right
 322  * root bridge.
 323  * Note that the returned IO or memory base is a physical address
 324  */
 325
 326 SYSCALL_DEFINE3(pciconfig_iobase, long, which,
 327                 unsigned long, bus, unsigned long, devfn)
 328 {
 329         struct pci_controller* hose;
 330         long result = -EOPNOTSUPP;
 331
 332         hose = pci_bus_to_hose(bus);
 333         if (!hose)
 334                 return -ENODEV;
 335
 336         switch (which) {
 337         case IOBASE_BRIDGE_NUMBER:
 338                 return (long)hose->first_busno;
 339         case IOBASE_MEMORY:
 340                 return (long)hose->mem_offset[0];
 341         case IOBASE_IO:
 342                 return (long)hose->io_base_phys;
 343         case IOBASE_ISA_IO:
 344                 return (long)isa_io_base;
 345         case IOBASE_ISA_MEM:
 346                 return (long)isa_mem_base;
 347         }
 348
 349         return result;
 350 }