arch/unicore32/kernel/pci.c

   1 /*
   2  * linux/arch/unicore32/kernel/pci.c
   3  *
   4  * Code specific to PKUnity SoC and UniCore ISA
   5  *
   6  * Copyright (C) 2001-2010 GUAN Xue-tao
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  *  PCI bios-type initialisation for PCI machines
  13  *
  14  */
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/pci.h>
  19 #include <linux/slab.h>
  20 #include <linux/init.h>
  21 #include <linux/io.h>
  22
  23 static int debug_pci;
  24 static int use_firmware;
  25
  26 #define CONFIG_CMD(bus, devfn, where)   \
  27         (0x80000000 | (bus->number << 16) | (devfn << 8) | (where & ~3))
  28
  29 static int
  30 puv3_read_config(struct pci_bus *bus, unsigned int devfn, int where,
  31                         int size, u32 *value)
  32 {
  33         writel(CONFIG_CMD(bus, devfn, where), PCICFG_ADDR);
  34         switch (size) {
  35         case 1:
  36                 *value = (readl(PCICFG_DATA) >> ((where & 3) * 8)) & 0xFF;
  37                 break;
  38         case 2:
  39                 *value = (readl(PCICFG_DATA) >> ((where & 2) * 8)) & 0xFFFF;
  40                 break;
  41         case 4:
  42                 *value = readl(PCICFG_DATA);
  43                 break;
  44         }
  45         return PCIBIOS_SUCCESSFUL;
  46 }
  47
  48 static int
  49 puv3_write_config(struct pci_bus *bus, unsigned int devfn, int where,
  50                         int size, u32 value)
  51 {
  52         writel(CONFIG_CMD(bus, devfn, where), PCICFG_ADDR);
  53         switch (size) {
  54         case 1:
  55                 writel((readl(PCICFG_DATA) & ~FMASK(8, (where&3)*8))
  56                         | FIELD(value, 8, (where&3)*8), PCICFG_DATA);
  57                 break;
  58         case 2:
  59                 writel((readl(PCICFG_DATA) & ~FMASK(16, (where&2)*8))
  60                         | FIELD(value, 16, (where&2)*8), PCICFG_DATA);
  61                 break;
  62         case 4:
  63                 writel(value, PCICFG_DATA);
  64                 break;
  65         }
  66         return PCIBIOS_SUCCESSFUL;
  67 }
  68
  69 struct pci_ops pci_puv3_ops = {
  70         .read  = puv3_read_config,
  71         .write = puv3_write_config,
  72 };
  73
  74 void pci_puv3_preinit(void)
  75 {
  76         printk(KERN_DEBUG "PCI: PKUnity PCI Controller Initializing ...\n");
  77         /* config PCI bridge base */
  78         writel(io_v2p(PKUNITY_PCIBRI_BASE), PCICFG_BRIBASE);
  79
  80         writel(0, PCIBRI_AHBCTL0);
  81         writel(io_v2p(PKUNITY_PCIBRI_BASE) | PCIBRI_BARx_MEM, PCIBRI_AHBBAR0);
  82         writel(0xFFFF0000, PCIBRI_AHBAMR0);
  83         writel(0, PCIBRI_AHBTAR0);
  84
  85         writel(PCIBRI_CTLx_AT, PCIBRI_AHBCTL1);
  86         writel(io_v2p(PKUNITY_PCILIO_BASE) | PCIBRI_BARx_IO, PCIBRI_AHBBAR1);
  87         writel(0xFFFF0000, PCIBRI_AHBAMR1);
  88         writel(0x00000000, PCIBRI_AHBTAR1);
  89
  90         writel(PCIBRI_CTLx_PREF, PCIBRI_AHBCTL2);
  91         writel(io_v2p(PKUNITY_PCIMEM_BASE) | PCIBRI_BARx_MEM, PCIBRI_AHBBAR2);
  92         writel(0xF8000000, PCIBRI_AHBAMR2);
  93         writel(0, PCIBRI_AHBTAR2);
  94
  95         writel(io_v2p(PKUNITY_PCIAHB_BASE) | PCIBRI_BARx_MEM, PCIBRI_BAR1);
  96
  97         writel(PCIBRI_CTLx_AT | PCIBRI_CTLx_PREF, PCIBRI_PCICTL0);
  98         writel(io_v2p(PKUNITY_PCIAHB_BASE) | PCIBRI_BARx_MEM, PCIBRI_PCIBAR0);
  99         writel(0xF8000000, PCIBRI_PCIAMR0);
 100         writel(PKUNITY_SDRAM_BASE, PCIBRI_PCITAR0);
 101
 102         writel(readl(PCIBRI_CMD) | PCIBRI_CMD_IO | PCIBRI_CMD_MEM, PCIBRI_CMD);
 103 }
 104
 105 static int __init pci_puv3_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 106 {
 107         if (dev->bus->number == 0) {
 108 #ifdef CONFIG_ARCH_FPGA /* 4 pci slots */
 109                 if      (dev->devfn == 0x00)
 110                         return IRQ_PCIINTA;
 111                 else if (dev->devfn == 0x08)
 112                         return IRQ_PCIINTB;
 113                 else if (dev->devfn == 0x10)
 114                         return IRQ_PCIINTC;
 115                 else if (dev->devfn == 0x18)
 116                         return IRQ_PCIINTD;
 117 #endif
 118 #ifdef CONFIG_PUV3_DB0913 /* 3 pci slots */
 119                 if      (dev->devfn == 0x30)
 120                         return IRQ_PCIINTB;
 121                 else if (dev->devfn == 0x60)
 122                         return IRQ_PCIINTC;
 123                 else if (dev->devfn == 0x58)
 124                         return IRQ_PCIINTD;
 125 #endif
 126 #if     defined(CONFIG_PUV3_NB0916) || defined(CONFIG_PUV3_SMW0919)
 127                 /* only support 2 pci devices */
 128                 if      (dev->devfn == 0x00)
 129                         return IRQ_PCIINTC; /* sata */
 130 #endif
 131         }
 132         return -1;
 133 }
 134
 135 /*
 136  * Only first 128MB of memory can be accessed via PCI.
 137  * We use GFP_DMA to allocate safe buffers to do map/unmap.
 138  * This is really ugly and we need a better way of specifying
 139  * DMA-capable regions of memory.
 140  */
 141 void __init puv3_pci_adjust_zones(unsigned long *zone_size,
 142         unsigned long *zhole_size)
 143 {
 144         unsigned int sz = SZ_128M >> PAGE_SHIFT;
 145
 146         /*
 147          * Only adjust if > 128M on current system
 148          */
 149         if (zone_size[0] <= sz)
 150                 return;
 151
 152         zone_size[1] = zone_size[0] - sz;
 153         zone_size[0] = sz;
 154         zhole_size[1] = zhole_size[0];
 155         zhole_size[0] = 0;
 156 }
 157
 158 void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
 159 {
 160         if (debug_pci)
 161                 printk(KERN_DEBUG "PCI: Assigning IRQ %02d to %s\n",
 162                                 irq, pci_name(dev));
 163         pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
 164 }
 165
 166 /*
 167  * If the bus contains any of these devices, then we must not turn on
 168  * parity checking of any kind.
 169  */
 170 static inline int pdev_bad_for_parity(struct pci_dev *dev)
 171 {
 172         return 0;
 173 }
 174
 175 /*
 176  * pcibios_fixup_bus - Called after each bus is probed,
 177  * but before its children are examined.
 178  */
 179 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
 180 {
 181         struct pci_dev *dev;
 182         u16 features = PCI_COMMAND_SERR
 183                 | PCI_COMMAND_PARITY
 184                 | PCI_COMMAND_FAST_BACK;
 185
 186         bus->resource[0] = &ioport_resource;
 187         bus->resource[1] = &iomem_resource;
 188
 189         /*
 190          * Walk the devices on this bus, working out what we can
 191          * and can't support.
 192          */
 193         list_for_each_entry(dev, &bus->devices, bus_list) {
 194                 u16 status;
 195
 196                 pci_read_config_word(dev, PCI_STATUS, &status);
 197
 198                 /*
 199                  * If any device on this bus does not support fast back
 200                  * to back transfers, then the bus as a whole is not able
 201                  * to support them.  Having fast back to back transfers
 202                  * on saves us one PCI cycle per transaction.
 203                  */
 204                 if (!(status & PCI_STATUS_FAST_BACK))
 205                         features &= ~PCI_COMMAND_FAST_BACK;
 206
 207                 if (pdev_bad_for_parity(dev))
 208                         features &= ~(PCI_COMMAND_SERR
 209                                         | PCI_COMMAND_PARITY);
 210
 211                 switch (dev->class >> 8) {
 212                 case PCI_CLASS_BRIDGE_PCI:
 213                         pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status);
 214                         status |= PCI_BRIDGE_CTL_PARITY
 215                                 | PCI_BRIDGE_CTL_MASTER_ABORT;
 216                         status &= ~(PCI_BRIDGE_CTL_BUS_RESET
 217                                 | PCI_BRIDGE_CTL_FAST_BACK);
 218                         pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status);
 219                         break;
 220
 221                 case PCI_CLASS_BRIDGE_CARDBUS:
 222                         pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL,
 223                                         &status);
 224                         status |= PCI_CB_BRIDGE_CTL_PARITY
 225                                 | PCI_CB_BRIDGE_CTL_MASTER_ABORT;
 226                         pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL,
 227                                         status);
 228                         break;
 229                 }
 230         }
 231
 232         /*
 233          * Now walk the devices again, this time setting them up.
 234          */
 235         list_for_each_entry(dev, &bus->devices, bus_list) {
 236                 u16 cmd;
 237
 238                 pci_read_config_word(dev, PCI_COMMAND, &cmd);
 239                 cmd |= features;
 240                 pci_write_config_word(dev, PCI_COMMAND, cmd);
 241
 242                 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
 243                                       L1_CACHE_BYTES >> 2);
 244         }
 245
 246         /*
 247          * Propagate the flags to the PCI bridge.
 248          */
 249         if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 250                 if (features & PCI_COMMAND_FAST_BACK)
 251                         bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK;
 252                 if (features & PCI_COMMAND_PARITY)
 253                         bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY;
 254         }
 255
 256         /*
 257          * Report what we did for this bus
 258          */
 259         printk(KERN_INFO "PCI: bus%d: Fast back to back transfers %sabled\n",
 260                 bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis");
 261 }
 262 #ifdef CONFIG_HOTPLUG
 263 EXPORT_SYMBOL(pcibios_fixup_bus);
 264 #endif
 265
 266 static int __init pci_common_init(void)
 267 {
 268         struct pci_bus *puv3_bus;
 269
 270         pci_puv3_preinit();
 271
 272         puv3_bus = pci_scan_bus(0, &pci_puv3_ops, NULL);
 273
 274         if (!puv3_bus)
 275                 panic("PCI: unable to scan bus!");
 276
 277         pci_fixup_irqs(pci_common_swizzle, pci_puv3_map_irq);
 278
 279         if (!use_firmware) {
 280                 /*
 281                  * Size the bridge windows.
 282                  */
 283                 pci_bus_size_bridges(puv3_bus);
 284
 285                 /*
 286                  * Assign resources.
 287                  */
 288                 pci_bus_assign_resources(puv3_bus);
 289         }
 290
 291         /*
 292          * Tell drivers about devices found.
 293          */
 294         pci_bus_add_devices(puv3_bus);
 295
 296         return 0;
 297 }
 298 subsys_initcall(pci_common_init);
 299
 300 char * __devinit pcibios_setup(char *str)
 301 {
 302         if (!strcmp(str, "debug")) {
 303                 debug_pci = 1;
 304                 return NULL;
 305         } else if (!strcmp(str, "firmware")) {
 306                 use_firmware = 1;
 307                 return NULL;
 308         }
 309         return str;
 310 }
 311
 312 /*
 313  * From arch/i386/kernel/pci-i386.c:
 314  *
 315  * We need to avoid collisions with `mirrored' VGA ports
 316  * and other strange ISA hardware, so we always want the
 317  * addresses to be allocated in the 0x000-0x0ff region
 318  * modulo 0x400.
 319  *
 320  * Why? Because some silly external IO cards only decode
 321  * the low 10 bits of the IO address. The 0x00-0xff region
 322  * is reserved for motherboard devices that decode all 16
 323  * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
 324  * but we want to try to avoid allocating at 0x2900-0x2bff
 325  * which might be mirrored at 0x0100-0x03ff..
 326  */
 327 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
 328                                 resource_size_t size, resource_size_t align)
 329 {
 330         resource_size_t start = res->start;
 331
 332         if (res->flags & IORESOURCE_IO && start & 0x300)
 333                 start = (start + 0x3ff) & ~0x3ff;
 334
 335         start = (start + align - 1) & ~(align - 1);
 336
 337         return start;
 338 }
 339
 340 /**
 341  * pcibios_enable_device - Enable I/O and memory.
 342  * @dev: PCI device to be enabled
 343  */
 344 int pcibios_enable_device(struct pci_dev *dev, int mask)
 345 {
 346         u16 cmd, old_cmd;
 347         int idx;
 348         struct resource *r;
 349
 350         pci_read_config_word(dev, PCI_COMMAND, &cmd);
 351         old_cmd = cmd;
 352         for (idx = 0; idx < 6; idx++) {
 353                 /* Only set up the requested stuff */
 354                 if (!(mask & (1 << idx)))
 355                         continue;
 356
 357                 r = dev->resource + idx;
 358                 if (!r->start && r->end) {
 359                         printk(KERN_ERR "PCI: Device %s not available because"
 360                                " of resource collisions\n", pci_name(dev));
 361                         return -EINVAL;
 362                 }
 363                 if (r->flags & IORESOURCE_IO)
 364                         cmd |= PCI_COMMAND_IO;
 365                 if (r->flags & IORESOURCE_MEM)
 366                         cmd |= PCI_COMMAND_MEMORY;
 367         }
 368
 369         /*
 370          * Bridges (eg, cardbus bridges) need to be fully enabled
 371          */
 372         if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
 373                 cmd |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
 374
 375         if (cmd != old_cmd) {
 376                 printk("PCI: enabling device %s (%04x -> %04x)\n",
 377                        pci_name(dev), old_cmd, cmd);
 378                 pci_write_config_word(dev, PCI_COMMAND, cmd);
 379         }
 380         return 0;
 381 }
 382
 383 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 384                         enum pci_mmap_state mmap_state, int write_combine)
 385 {
 386         unsigned long phys;
 387
 388         if (mmap_state == pci_mmap_io)
 389                 return -EINVAL;
 390
 391         phys = vma->vm_pgoff;
 392
 393         /*
 394          * Mark this as IO
 395          */
 396         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 397
 398         if (remap_pfn_range(vma, vma->vm_start, phys,
 399                              vma->vm_end - vma->vm_start,
 400                              vma->vm_page_prot))
 401                 return -EAGAIN;
 402
 403         return 0;
 404 }