arch/sh/drivers/pci/pci.c

   1 /*
   2  * New-style PCI core.
   3  *
   4  * Copyright (c) 2004 - 2009  Paul Mundt
   5  * Copyright (c) 2002  M. R. Brown
   6  *
   7  * Modelled after arch/mips/pci/pci.c:
   8  *  Copyright (C) 2003, 04 Ralf Baechle (ralf@linux-mips.org)
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file "COPYING" in the main directory of this archive
  12  * for more details.
  13  */
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/pci.h>
  17 #include <linux/init.h>
  18 #include <linux/types.h>
  19 #include <linux/dma-debug.h>
  20 #include <linux/io.h>
  21 #include <linux/mutex.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/export.h>
  24
  25 unsigned long PCIBIOS_MIN_IO = 0x0000;
  26 unsigned long PCIBIOS_MIN_MEM = 0;
  27
  28 /*
  29  * The PCI controller list.
  30  */
  31 static struct pci_channel *hose_head, **hose_tail = &hose_head;
  32
  33 static int pci_initialized;
  34
  35 static void pcibios_scanbus(struct pci_channel *hose)
  36 {
  37         static int next_busno;
  38         static int need_domain_info;
  39         LIST_HEAD(resources);
  40         struct resource *res;
  41         resource_size_t offset;
  42         int i;
  43         struct pci_bus *bus;
  44
  45         for (i = 0; i < hose->nr_resources; i++) {
  46                 res = hose->resources + i;
  47                 offset = 0;
  48                 if (res->flags & IORESOURCE_IO)
  49                         offset = hose->io_offset;
  50                 else if (res->flags & IORESOURCE_MEM)
  51                         offset = hose->mem_offset;
  52                 pci_add_resource_offset(&resources, res, offset);
  53         }
  54
  55         bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
  56                                 &resources);
  57         hose->bus = bus;
  58
  59         need_domain_info = need_domain_info || hose->index;
  60         hose->need_domain_info = need_domain_info;
  61         if (bus) {
  62                 next_busno = bus->busn_res.end + 1;
  63                 /* Don't allow 8-bit bus number overflow inside the hose -
  64                    reserve some space for bridges. */
  65                 if (next_busno > 224) {
  66                         next_busno = 0;
  67                         need_domain_info = 1;
  68                 }
  69
  70                 pci_bus_size_bridges(bus);
  71                 pci_bus_assign_resources(bus);
  72         } else {
  73                 pci_free_resource_list(&resources);
  74         }
  75 }
  76
  77 /*
  78  * This interrupt-safe spinlock protects all accesses to PCI
  79  * configuration space.
  80  */
  81 DEFINE_RAW_SPINLOCK(pci_config_lock);
  82 static DEFINE_MUTEX(pci_scan_mutex);
  83
  84 int register_pci_controller(struct pci_channel *hose)
  85 {
  86         int i;
  87
  88         for (i = 0; i < hose->nr_resources; i++) {
  89                 struct resource *res = hose->resources + i;
  90
  91                 if (res->flags & IORESOURCE_IO) {
  92                         if (request_resource(&ioport_resource, res) < 0)
  93                                 goto out;
  94                 } else {
  95                         if (request_resource(&iomem_resource, res) < 0)
  96                                 goto out;
  97                 }
  98         }
  99
 100         *hose_tail = hose;
 101         hose_tail = &hose->next;
 102
 103         /*
 104          * Do not panic here but later - this might happen before console init.
 105          */
 106         if (!hose->io_map_base) {
 107                 printk(KERN_WARNING
 108                        "registering PCI controller with io_map_base unset\n");
 109         }
 110
 111         /*
 112          * Setup the ERR/PERR and SERR timers, if available.
 113          */
 114         pcibios_enable_timers(hose);
 115
 116         /*
 117          * Scan the bus if it is register after the PCI subsystem
 118          * initialization.
 119          */
 120         if (pci_initialized) {
 121                 mutex_lock(&pci_scan_mutex);
 122                 pcibios_scanbus(hose);
 123                 mutex_unlock(&pci_scan_mutex);
 124         }
 125
 126         return 0;
 127
 128 out:
 129         for (--i; i >= 0; i--)
 130                 release_resource(&hose->resources[i]);
 131
 132         printk(KERN_WARNING "Skipping PCI bus scan due to resource conflict\n");
 133         return -1;
 134 }
 135
 136 static int __init pcibios_init(void)
 137 {
 138         struct pci_channel *hose;
 139
 140         /* Scan all of the recorded PCI controllers.  */
 141         for (hose = hose_head; hose; hose = hose->next)
 142                 pcibios_scanbus(hose);
 143
 144         pci_fixup_irqs(pci_common_swizzle, pcibios_map_platform_irq);
 145
 146         dma_debug_add_bus(&pci_bus_type);
 147
 148         pci_initialized = 1;
 149
 150         return 0;
 151 }
 152 subsys_initcall(pcibios_init);
 153
 154 /*
 155  *  Called after each bus is probed, but before its children
 156  *  are examined.
 157  */
 158 void pcibios_fixup_bus(struct pci_bus *bus)
 159 {
 160 }
 161
 162 /*
 163  * We need to avoid collisions with `mirrored' VGA ports
 164  * and other strange ISA hardware, so we always want the
 165  * addresses to be allocated in the 0x000-0x0ff region
 166  * modulo 0x400.
 167  */
 168 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
 169                                 resource_size_t size, resource_size_t align)
 170 {
 171         struct pci_dev *dev = data;
 172         struct pci_channel *hose = dev->sysdata;
 173         resource_size_t start = res->start;
 174
 175         if (res->flags & IORESOURCE_IO) {
 176                 if (start < PCIBIOS_MIN_IO + hose->resources[0].start)
 177                         start = PCIBIOS_MIN_IO + hose->resources[0].start;
 178
 179                 /*
 180                  * Put everything into 0x00-0xff region modulo 0x400.
 181                  */
 182                 if (start & 0x300)
 183                         start = (start + 0x3ff) & ~0x3ff;
 184         }
 185
 186         return start;
 187 }
 188
 189 static void __init
 190 pcibios_bus_report_status_early(struct pci_channel *hose,
 191                                 int top_bus, int current_bus,
 192                                 unsigned int status_mask, int warn)
 193 {
 194         unsigned int pci_devfn;
 195         u16 status;
 196         int ret;
 197
 198         for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
 199                 if (PCI_FUNC(pci_devfn))
 200                         continue;
 201                 ret = early_read_config_word(hose, top_bus, current_bus,
 202                                              pci_devfn, PCI_STATUS, &status);
 203                 if (ret != PCIBIOS_SUCCESSFUL)
 204                         continue;
 205                 if (status == 0xffff)
 206                         continue;
 207
 208                 early_write_config_word(hose, top_bus, current_bus,
 209                                         pci_devfn, PCI_STATUS,
 210                                         status & status_mask);
 211                 if (warn)
 212                         printk("(%02x:%02x: %04X) ", current_bus,
 213                                pci_devfn, status);
 214         }
 215 }
 216
 217 /*
 218  * We can't use pci_find_device() here since we are
 219  * called from interrupt context.
 220  */
 221 static void __init_refok
 222 pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
 223                           int warn)
 224 {
 225         struct pci_dev *dev;
 226
 227         list_for_each_entry(dev, &bus->devices, bus_list) {
 228                 u16 status;
 229
 230                 /*
 231                  * ignore host bridge - we handle
 232                  * that separately
 233                  */
 234                 if (dev->bus->number == 0 && dev->devfn == 0)
 235                         continue;
 236
 237                 pci_read_config_word(dev, PCI_STATUS, &status);
 238                 if (status == 0xffff)
 239                         continue;
 240
 241                 if ((status & status_mask) == 0)
 242                         continue;
 243
 244                 /* clear the status errors */
 245                 pci_write_config_word(dev, PCI_STATUS, status & status_mask);
 246
 247                 if (warn)
 248                         printk("(%s: %04X) ", pci_name(dev), status);
 249         }
 250
 251         list_for_each_entry(dev, &bus->devices, bus_list)
 252                 if (dev->subordinate)
 253                         pcibios_bus_report_status(dev->subordinate, status_mask, warn);
 254 }
 255
 256 void __init_refok pcibios_report_status(unsigned int status_mask, int warn)
 257 {
 258         struct pci_channel *hose;
 259
 260         for (hose = hose_head; hose; hose = hose->next) {
 261                 if (unlikely(!hose->bus))
 262                         pcibios_bus_report_status_early(hose, hose_head->index,
 263                                         hose->index, status_mask, warn);
 264                 else
 265                         pcibios_bus_report_status(hose->bus, status_mask, warn);
 266         }
 267 }
 268
 269 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 270                         enum pci_mmap_state mmap_state, int write_combine)
 271 {
 272         /*
 273          * I/O space can be accessed via normal processor loads and stores on
 274          * this platform but for now we elect not to do this and portable
 275          * drivers should not do this anyway.
 276          */
 277         if (mmap_state == pci_mmap_io)
 278                 return -EINVAL;
 279
 280         /*
 281          * Ignore write-combine; for now only return uncached mappings.
 282          */
 283         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 284
 285         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 286                                vma->vm_end - vma->vm_start,
 287                                vma->vm_page_prot);
 288 }
 289
 290 #ifndef CONFIG_GENERIC_IOMAP
 291
 292 void __iomem *__pci_ioport_map(struct pci_dev *dev,
 293                                unsigned long port, unsigned int nr)
 294 {
 295         struct pci_channel *chan = dev->sysdata;
 296
 297         if (unlikely(!chan->io_map_base)) {
 298                 chan->io_map_base = sh_io_port_base;
 299
 300                 if (pci_domains_supported)
 301                         panic("To avoid data corruption io_map_base MUST be "
 302                               "set with multiple PCI domains.");
 303         }
 304
 305         return (void __iomem *)(chan->io_map_base + port);
 306 }
 307
 308 void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
 309 {
 310         iounmap(addr);
 311 }
 312 EXPORT_SYMBOL(pci_iounmap);
 313
 314 #endif /* CONFIG_GENERIC_IOMAP */
 315
 316 EXPORT_SYMBOL(PCIBIOS_MIN_IO);
 317 EXPORT_SYMBOL(PCIBIOS_MIN_MEM);