arch/arm/mach-versatile/pci.c

   1 /*
   2  *  linux/arch/arm/mach-versatile/pci.c
   3  *
   4  * (C) Copyright Koninklijke Philips Electronics NV 2004. All rights reserved.
   5  * You can redistribute and/or modify this software under the terms of version 2
   6  * of the GNU General Public License as published by the Free Software Foundation.
   7  * THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
   8  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   9  * General Public License for more details.
  10  * Koninklijke Philips Electronics nor its subsidiaries is obligated to provide any support for this software.
  11  *
  12  * ARM Versatile PCI driver.
  13  *
  14  * 14/04/2005 Initial version, colin.king@philips.com
  15  *
  16  */
  17 #include <linux/kernel.h>
  18 #include <linux/pci.h>
  19 #include <linux/slab.h>
  20 #include <linux/ioport.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/init.h>
  24
  25 #include <asm/hardware.h>
  26 #include <asm/io.h>
  27 #include <asm/irq.h>
  28 #include <asm/system.h>
  29 #include <asm/mach/pci.h>
  30
  31 /*
  32  * these spaces are mapped using the following base registers:
  33  *
  34  * Usage Local Bus Memory         Base/Map registers used
  35  *
  36  * Mem   50000000 - 5FFFFFFF      LB_BASE0/LB_MAP0,  non prefetch
  37  * Mem   60000000 - 6FFFFFFF      LB_BASE1/LB_MAP1,  prefetch
  38  * IO    44000000 - 4FFFFFFF      LB_BASE2/LB_MAP2,  IO
  39  * Cfg   42000000 - 42FFFFFF      PCI config
  40  *
  41  */
  42 #define __IO_ADDRESS(n) ((void __iomem *)(unsigned long)IO_ADDRESS(n))
  43 #define SYS_PCICTL              __IO_ADDRESS(VERSATILE_SYS_PCICTL)
  44 #define PCI_IMAP0               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x0)
  45 #define PCI_IMAP1               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x4)
  46 #define PCI_IMAP2               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x8)
  47 #define PCI_SMAP0               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x10)
  48 #define PCI_SMAP1               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x14)
  49 #define PCI_SMAP2               __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x18)
  50 #define PCI_SELFID              __IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0xc)
  51
  52 #define DEVICE_ID_OFFSET                0x00
  53 #define CSR_OFFSET                      0x04
  54 #define CLASS_ID_OFFSET                 0x08
  55
  56 #define VP_PCI_DEVICE_ID                0x030010ee
  57 #define VP_PCI_CLASS_ID                 0x0b400000
  58
  59 static unsigned long pci_slot_ignore = 0;
  60
  61 static int __init versatile_pci_slot_ignore(char *str)
  62 {
  63         int retval;
  64         int slot;
  65
  66         while ((retval = get_option(&str,&slot))) {
  67                 if ((slot < 0) || (slot > 31)) {
  68                         printk("Illegal slot value: %d\n",slot);
  69                 } else {
  70                         pci_slot_ignore |= (1 << slot);
  71                 }
  72         }
  73         return 1;
  74 }
  75
  76 __setup("pci_slot_ignore=", versatile_pci_slot_ignore);
  77
  78
  79 static void __iomem *__pci_addr(struct pci_bus *bus,
  80                                 unsigned int devfn, int offset)
  81 {
  82         unsigned int busnr = bus->number;
  83
  84         /*
  85          * Trap out illegal values
  86          */
  87         if (offset > 255)
  88                 BUG();
  89         if (busnr > 255)
  90                 BUG();
  91         if (devfn > 255)
  92                 BUG();
  93
  94         return VERSATILE_PCI_CFG_VIRT_BASE + ((busnr << 16) |
  95                 (PCI_SLOT(devfn) << 11) | (PCI_FUNC(devfn) << 8) | offset);
  96 }
  97
  98 static int versatile_read_config(struct pci_bus *bus, unsigned int devfn, int where,
  99                                  int size, u32 *val)
 100 {
 101         void __iomem *addr = __pci_addr(bus, devfn, where & ~3);
 102         u32 v;
 103         int slot = PCI_SLOT(devfn);
 104
 105         if (pci_slot_ignore & (1 << slot)) {
 106                 /* Ignore this slot */
 107                 switch (size) {
 108                 case 1:
 109                         v = 0xff;
 110                         break;
 111                 case 2:
 112                         v = 0xffff;
 113                         break;
 114                 default:
 115                         v = 0xffffffff;
 116                 }
 117         } else {
 118                 switch (size) {
 119                 case 1:
 120                         v = __raw_readl(addr);
 121                         if (where & 2) v >>= 16;
 122                         if (where & 1) v >>= 8;
 123                         v &= 0xff;
 124                         break;
 125
 126                 case 2:
 127                         v = __raw_readl(addr);
 128                         if (where & 2) v >>= 16;
 129                         v &= 0xffff;
 130                         break;
 131
 132                 default:
 133                         v = __raw_readl(addr);
 134                         break;
 135                 }
 136         }
 137
 138         *val = v;
 139         return PCIBIOS_SUCCESSFUL;
 140 }
 141
 142 static int versatile_write_config(struct pci_bus *bus, unsigned int devfn, int where,
 143                                   int size, u32 val)
 144 {
 145         void __iomem *addr = __pci_addr(bus, devfn, where);
 146         int slot = PCI_SLOT(devfn);
 147
 148         if (pci_slot_ignore & (1 << slot)) {
 149                 return PCIBIOS_SUCCESSFUL;
 150         }
 151
 152         switch (size) {
 153         case 1:
 154                 __raw_writeb((u8)val, addr);
 155                 break;
 156
 157         case 2:
 158                 __raw_writew((u16)val, addr);
 159                 break;
 160
 161         case 4:
 162                 __raw_writel(val, addr);
 163                 break;
 164         }
 165
 166         return PCIBIOS_SUCCESSFUL;
 167 }
 168
 169 static struct pci_ops pci_versatile_ops = {
 170         .read   = versatile_read_config,
 171         .write  = versatile_write_config,
 172 };
 173
 174 static struct resource io_mem = {
 175         .name   = "PCI I/O space",
 176         .start  = VERSATILE_PCI_MEM_BASE0,
 177         .end    = VERSATILE_PCI_MEM_BASE0+VERSATILE_PCI_MEM_BASE0_SIZE-1,
 178         .flags  = IORESOURCE_IO,
 179 };
 180
 181 static struct resource non_mem = {
 182         .name   = "PCI non-prefetchable",
 183         .start  = VERSATILE_PCI_MEM_BASE1,
 184         .end    = VERSATILE_PCI_MEM_BASE1+VERSATILE_PCI_MEM_BASE1_SIZE-1,
 185         .flags  = IORESOURCE_MEM,
 186 };
 187
 188 static struct resource pre_mem = {
 189         .name   = "PCI prefetchable",
 190         .start  = VERSATILE_PCI_MEM_BASE2,
 191         .end    = VERSATILE_PCI_MEM_BASE2+VERSATILE_PCI_MEM_BASE2_SIZE-1,
 192         .flags  = IORESOURCE_MEM | IORESOURCE_PREFETCH,
 193 };
 194
 195 static int __init pci_versatile_setup_resources(struct resource **resource)
 196 {
 197         int ret = 0;
 198
 199         ret = request_resource(&iomem_resource, &io_mem);
 200         if (ret) {
 201                 printk(KERN_ERR "PCI: unable to allocate I/O "
 202                        "memory region (%d)\n", ret);
 203                 goto out;
 204         }
 205         ret = request_resource(&iomem_resource, &non_mem);
 206         if (ret) {
 207                 printk(KERN_ERR "PCI: unable to allocate non-prefetchable "
 208                        "memory region (%d)\n", ret);
 209                 goto release_io_mem;
 210         }
 211         ret = request_resource(&iomem_resource, &pre_mem);
 212         if (ret) {
 213                 printk(KERN_ERR "PCI: unable to allocate prefetchable "
 214                        "memory region (%d)\n", ret);
 215                 goto release_non_mem;
 216         }
 217
 218         /*
 219          * bus->resource[0] is the IO resource for this bus
 220          * bus->resource[1] is the mem resource for this bus
 221          * bus->resource[2] is the prefetch mem resource for this bus
 222          */
 223         resource[0] = &io_mem;
 224         resource[1] = &non_mem;
 225         resource[2] = &pre_mem;
 226
 227         goto out;
 228
 229  release_non_mem:
 230         release_resource(&non_mem);
 231  release_io_mem:
 232         release_resource(&io_mem);
 233  out:
 234         return ret;
 235 }
 236
 237 int __init pci_versatile_setup(int nr, struct pci_sys_data *sys)
 238 {
 239         int ret = 0;
 240         int i;
 241         int myslot = -1;
 242         unsigned long val;
 243         void __iomem *local_pci_cfg_base;
 244
 245         val = __raw_readl(SYS_PCICTL);
 246         if (!(val & 1)) {
 247                 printk("Not plugged into PCI backplane!\n");
 248                 ret = -EIO;
 249                 goto out;
 250         }
 251
 252         if (nr == 0) {
 253                 sys->mem_offset = 0;
 254                 ret = pci_versatile_setup_resources(sys->resource);
 255                 if (ret < 0) {
 256                         printk("pci_versatile_setup: resources... oops?\n");
 257                         goto out;
 258                 }
 259         } else {
 260                 printk("pci_versatile_setup: resources... nr == 0??\n");
 261                 goto out;
 262         }
 263
 264         /*
 265          *  We need to discover the PCI core first to configure itself
 266          *  before the main PCI probing is performed
 267          */
 268         for (i=0; i<32; i++)
 269                 if ((__raw_readl(VERSATILE_PCI_VIRT_BASE+(i<<11)+DEVICE_ID_OFFSET) == VP_PCI_DEVICE_ID) &&
 270                     (__raw_readl(VERSATILE_PCI_VIRT_BASE+(i<<11)+CLASS_ID_OFFSET) == VP_PCI_CLASS_ID)) {
 271                         myslot = i;
 272                         break;
 273                 }
 274
 275         if (myslot == -1) {
 276                 printk("Cannot find PCI core!\n");
 277                 ret = -EIO;
 278                 goto out;
 279         }
 280
 281         printk("PCI core found (slot %d)\n",myslot);
 282
 283         __raw_writel(myslot, PCI_SELFID);
 284         local_pci_cfg_base = VERSATILE_PCI_CFG_VIRT_BASE + (myslot << 11);
 285
 286         val = __raw_readl(local_pci_cfg_base + CSR_OFFSET);
 287         val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
 288         __raw_writel(val, local_pci_cfg_base + CSR_OFFSET);
 289
 290         /*
 291          * Configure the PCI inbound memory windows to be 1:1 mapped to SDRAM
 292          */
 293         __raw_writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_0);
 294         __raw_writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_1);
 295         __raw_writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_2);
 296
 297         /*
 298          * Do not to map Versatile FPGA PCI device into memory space
 299          */
 300         pci_slot_ignore |= (1 << myslot);
 301         ret = 1;
 302
 303  out:
 304         return ret;
 305 }
 306
 307
 308 struct pci_bus *pci_versatile_scan_bus(int nr, struct pci_sys_data *sys)
 309 {
 310         return pci_scan_bus(sys->busnr, &pci_versatile_ops, sys);
 311 }
 312
 313 void __init pci_versatile_preinit(void)
 314 {
 315         __raw_writel(VERSATILE_PCI_MEM_BASE0 >> 28, PCI_IMAP0);
 316         __raw_writel(VERSATILE_PCI_MEM_BASE1 >> 28, PCI_IMAP1);
 317         __raw_writel(VERSATILE_PCI_MEM_BASE2 >> 28, PCI_IMAP2);
 318
 319         __raw_writel(PHYS_OFFSET >> 28, PCI_SMAP0);
 320         __raw_writel(PHYS_OFFSET >> 28, PCI_SMAP1);
 321         __raw_writel(PHYS_OFFSET >> 28, PCI_SMAP2);
 322
 323         __raw_writel(1, SYS_PCICTL);
 324 }
 325
 326 /*
 327  * map the specified device/slot/pin to an IRQ.   Different backplanes may need to modify this.
 328  */
 329 static int __init versatile_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
 330 {
 331         int irq;
 332         int devslot = PCI_SLOT(dev->devfn);
 333
 334         /* slot,  pin,  irq
 335          *  24     1     27
 336          *  25     1     28
 337          *  26     1     29
 338          *  27     1     30
 339          */
 340         irq = 27 + ((slot + pin - 1) & 3);
 341
 342         printk("PCI map irq: slot %d, pin %d, devslot %d, irq: %d\n",slot,pin,devslot,irq);
 343
 344         return irq;
 345 }
 346
 347 static struct hw_pci versatile_pci __initdata = {
 348         .swizzle                = NULL,
 349         .map_irq                = versatile_map_irq,
 350         .nr_controllers         = 1,
 351         .setup                  = pci_versatile_setup,
 352         .scan                   = pci_versatile_scan_bus,
 353         .preinit                = pci_versatile_preinit,
 354 };
 355
 356 static int __init versatile_pci_init(void)
 357 {
 358         pci_common_init(&versatile_pci);
 359         return 0;
 360 }
 361
 362 subsys_initcall(versatile_pci_init);