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
  23 unsigned long PCIBIOS_MIN_IO = 0x0000;
  24 unsigned long PCIBIOS_MIN_MEM = 0;
  25
  26 /*
  27  * The PCI controller list.
  28  */
  29 static struct pci_channel *hose_head, **hose_tail = &hose_head;
  30
  31 static int pci_initialized;
  32
  33 static void __devinit pcibios_scanbus(struct pci_channel *hose)
  34 {
  35         static int next_busno;
  36         struct pci_bus *bus;
  37
  38         bus = pci_scan_bus(next_busno, hose->pci_ops, hose);
  39         if (bus) {
  40                 next_busno = bus->subordinate + 1;
  41                 /* Don't allow 8-bit bus number overflow inside the hose -
  42                    reserve some space for bridges. */
  43                 if (next_busno > 224)
  44                         next_busno = 0;
  45
  46                 pci_bus_size_bridges(bus);
  47                 pci_bus_assign_resources(bus);
  48                 pci_enable_bridges(bus);
  49         }
  50 }
  51
  52 static DEFINE_MUTEX(pci_scan_mutex);
  53
  54 void __devinit register_pci_controller(struct pci_channel *hose)
  55 {
  56         request_resource(&iomem_resource, hose->mem_resource);
  57         request_resource(&ioport_resource, hose->io_resource);
  58
  59         *hose_tail = hose;
  60         hose_tail = &hose->next;
  61
  62         /*
  63          * Do not panic here but later - this might hapen before console init.
  64          */
  65         if (!hose->io_map_base) {
  66                 printk(KERN_WARNING
  67                        "registering PCI controller with io_map_base unset\n");
  68         }
  69
  70         /*
  71          * Scan the bus if it is register after the PCI subsystem
  72          * initialization.
  73          */
  74         if (pci_initialized) {
  75                 mutex_lock(&pci_scan_mutex);
  76                 pcibios_scanbus(hose);
  77                 mutex_unlock(&pci_scan_mutex);
  78         }
  79 }
  80
  81 static int __init pcibios_init(void)
  82 {
  83         struct pci_channel *hose;
  84
  85         /* Scan all of the recorded PCI controllers.  */
  86         for (hose = hose_head; hose; hose = hose->next)
  87                 pcibios_scanbus(hose);
  88
  89         pci_fixup_irqs(pci_common_swizzle, pcibios_map_platform_irq);
  90
  91         dma_debug_add_bus(&pci_bus_type);
  92
  93         pci_initialized = 1;
  94
  95         return 0;
  96 }
  97 subsys_initcall(pcibios_init);
  98
  99 static void pcibios_fixup_device_resources(struct pci_dev *dev,
 100         struct pci_bus *bus)
 101 {
 102         /* Update device resources.  */
 103         struct pci_channel *hose = bus->sysdata;
 104         unsigned long offset = 0;
 105         int i;
 106
 107         for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 108                 if (!dev->resource[i].start)
 109                         continue;
 110                 if (dev->resource[i].flags & IORESOURCE_PCI_FIXED)
 111                         continue;
 112                 if (dev->resource[i].flags & IORESOURCE_IO)
 113                         offset = hose->io_offset;
 114                 else if (dev->resource[i].flags & IORESOURCE_MEM)
 115                         offset = hose->mem_offset;
 116
 117                 dev->resource[i].start += offset;
 118                 dev->resource[i].end += offset;
 119         }
 120 }
 121
 122 /*
 123  *  Called after each bus is probed, but before its children
 124  *  are examined.
 125  */
 126 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
 127 {
 128         struct pci_dev *dev = bus->self;
 129         struct list_head *ln;
 130         struct pci_channel *chan = bus->sysdata;
 131
 132         if (!dev) {
 133                 bus->resource[0] = chan->io_resource;
 134                 bus->resource[1] = chan->mem_resource;
 135         }
 136
 137         for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
 138                 dev = pci_dev_b(ln);
 139
 140                 if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
 141                         pcibios_fixup_device_resources(dev, bus);
 142         }
 143 }
 144
 145 /*
 146  * We need to avoid collisions with `mirrored' VGA ports
 147  * and other strange ISA hardware, so we always want the
 148  * addresses to be allocated in the 0x000-0x0ff region
 149  * modulo 0x400.
 150  */
 151 resource_size_t pcibios_align_resource(void *data, struct resource *res,
 152                                 resource_size_t size, resource_size_t align)
 153 {
 154         struct pci_dev *dev = data;
 155         struct pci_channel *chan = dev->sysdata;
 156         resource_size_t start = res->start;
 157
 158         if (res->flags & IORESOURCE_IO) {
 159                 if (start < PCIBIOS_MIN_IO + chan->io_resource->start)
 160                         start = PCIBIOS_MIN_IO + chan->io_resource->start;
 161
 162                 /*
 163                  * Put everything into 0x00-0xff region modulo 0x400.
 164                  */
 165                 if (start & 0x300) {
 166                         start = (start + 0x3ff) & ~0x3ff;
 167                         res->start = start;
 168                 }
 169         } else if (res->flags & IORESOURCE_MEM) {
 170                 if (start < PCIBIOS_MIN_MEM + chan->mem_resource->start)
 171                         start = PCIBIOS_MIN_MEM + chan->mem_resource->start;
 172         }
 173
 174         return start;
 175 }
 176
 177 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
 178                          struct resource *res)
 179 {
 180         struct pci_channel *hose = dev->sysdata;
 181         unsigned long offset = 0;
 182
 183         if (res->flags & IORESOURCE_IO)
 184                 offset = hose->io_offset;
 185         else if (res->flags & IORESOURCE_MEM)
 186                 offset = hose->mem_offset;
 187
 188         region->start = res->start - offset;
 189         region->end = res->end - offset;
 190 }
 191
 192 void __devinit
 193 pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
 194                         struct pci_bus_region *region)
 195 {
 196         struct pci_channel *hose = dev->sysdata;
 197         unsigned long offset = 0;
 198
 199         if (res->flags & IORESOURCE_IO)
 200                 offset = hose->io_offset;
 201         else if (res->flags & IORESOURCE_MEM)
 202                 offset = hose->mem_offset;
 203
 204         res->start = region->start + offset;
 205         res->end = region->end + offset;
 206 }
 207
 208 int pcibios_enable_device(struct pci_dev *dev, int mask)
 209 {
 210         u16 cmd, old_cmd;
 211         int idx;
 212         struct resource *r;
 213
 214         pci_read_config_word(dev, PCI_COMMAND, &cmd);
 215         old_cmd = cmd;
 216         for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
 217                 /* Only set up the requested stuff */
 218                 if (!(mask & (1<<idx)))
 219                         continue;
 220
 221                 r = &dev->resource[idx];
 222                 if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
 223                         continue;
 224                 if ((idx == PCI_ROM_RESOURCE) &&
 225                                 (!(r->flags & IORESOURCE_ROM_ENABLE)))
 226                         continue;
 227                 if (!r->start && r->end) {
 228                         printk(KERN_ERR "PCI: Device %s not available "
 229                                "because of resource collisions\n",
 230                                pci_name(dev));
 231                         return -EINVAL;
 232                 }
 233                 if (r->flags & IORESOURCE_IO)
 234                         cmd |= PCI_COMMAND_IO;
 235                 if (r->flags & IORESOURCE_MEM)
 236                         cmd |= PCI_COMMAND_MEMORY;
 237         }
 238         if (cmd != old_cmd) {
 239                 printk("PCI: Enabling device %s (%04x -> %04x)\n",
 240                        pci_name(dev), old_cmd, cmd);
 241                 pci_write_config_word(dev, PCI_COMMAND, cmd);
 242         }
 243         return 0;
 244 }
 245
 246 /*
 247  *  If we set up a device for bus mastering, we need to check and set
 248  *  the latency timer as it may not be properly set.
 249  */
 250 static unsigned int pcibios_max_latency = 255;
 251
 252 void pcibios_set_master(struct pci_dev *dev)
 253 {
 254         u8 lat;
 255         pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
 256         if (lat < 16)
 257                 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
 258         else if (lat > pcibios_max_latency)
 259                 lat = pcibios_max_latency;
 260         else
 261                 return;
 262         printk(KERN_INFO "PCI: Setting latency timer of device %s to %d\n",
 263                pci_name(dev), lat);
 264         pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
 265 }
 266
 267 void __init pcibios_update_irq(struct pci_dev *dev, int irq)
 268 {
 269         pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
 270 }
 271
 272 char * __devinit pcibios_setup(char *str)
 273 {
 274         return str;
 275 }
 276
 277 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 278                         enum pci_mmap_state mmap_state, int write_combine)
 279 {
 280         /*
 281          * I/O space can be accessed via normal processor loads and stores on
 282          * this platform but for now we elect not to do this and portable
 283          * drivers should not do this anyway.
 284          */
 285         if (mmap_state == pci_mmap_io)
 286                 return -EINVAL;
 287
 288         /*
 289          * Ignore write-combine; for now only return uncached mappings.
 290          */
 291         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 292
 293         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 294                                vma->vm_end - vma->vm_start,
 295                                vma->vm_page_prot);
 296 }
 297
 298 #ifndef CONFIG_GENERIC_IOMAP
 299
 300 static void __iomem *ioport_map_pci(struct pci_dev *dev,
 301                                     unsigned long port, unsigned int nr)
 302 {
 303         struct pci_channel *chan = dev->sysdata;
 304
 305         if (!chan->io_map_base)
 306                 chan->io_map_base = generic_io_base;
 307
 308         return (void __iomem *)(chan->io_map_base + port);
 309 }
 310
 311 void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
 312 {
 313         resource_size_t start = pci_resource_start(dev, bar);
 314         resource_size_t len = pci_resource_len(dev, bar);
 315         unsigned long flags = pci_resource_flags(dev, bar);
 316
 317         if (unlikely(!len || !start))
 318                 return NULL;
 319         if (maxlen && len > maxlen)
 320                 len = maxlen;
 321
 322         if (flags & IORESOURCE_IO)
 323                 return ioport_map_pci(dev, start, len);
 324
 325         /*
 326          * Presently the IORESOURCE_MEM case is a bit special, most
 327          * SH7751 style PCI controllers have PCI memory at a fixed
 328          * location in the address space where no remapping is desired.
 329          * With the IORESOURCE_MEM case more care has to be taken
 330          * to inhibit page table mapping for legacy cores, but this is
 331          * punted off to __ioremap().
 332          *                                      -- PFM.
 333          */
 334         if (flags & IORESOURCE_MEM) {
 335                 if (flags & IORESOURCE_CACHEABLE)
 336                         return ioremap(start, len);
 337
 338                 return ioremap_nocache(start, len);
 339         }
 340
 341         return NULL;
 342 }
 343 EXPORT_SYMBOL(pci_iomap);
 344
 345 void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
 346 {
 347         iounmap(addr);
 348 }
 349 EXPORT_SYMBOL(pci_iounmap);
 350
 351 #endif /* CONFIG_GENERIC_IOMAP */
 352
 353 #ifdef CONFIG_HOTPLUG
 354 EXPORT_SYMBOL(pcibios_resource_to_bus);
 355 EXPORT_SYMBOL(pcibios_bus_to_resource);
 356 EXPORT_SYMBOL(PCIBIOS_MIN_IO);
 357 EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
 358 #endif