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