arch/arm/mach-iop32x/pci.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * arch/arm/plat-iop/pci.c
   4  *
   5  * PCI support for the Intel IOP32X and IOP33X processors
   6  *
   7  * Author: Rory Bolt <rorybolt@pacbell.net>
   8  * Copyright (C) 2002 Rory Bolt
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/pci.h>
  13 #include <linux/slab.h>
  14 #include <linux/mm.h>
  15 #include <linux/init.h>
  16 #include <linux/ioport.h>
  17 #include <linux/io.h>
  18 #include <asm/irq.h>
  19 #include <asm/signal.h>
  20 #include <asm/mach/pci.h>
  21 #include "hardware.h"
  22 #include "iop3xx.h"
  23
  24 // #define DEBUG
  25
  26 #ifdef DEBUG
  27 #define  DBG(x...) printk(x)
  28 #else
  29 #define  DBG(x...) do { } while (0)
  30 #endif
  31
  32 /*
  33  * This routine builds either a type0 or type1 configuration command.  If the
  34  * bus is on the 803xx then a type0 made, else a type1 is created.
  35  */
  36 static u32 iop3xx_cfg_address(struct pci_bus *bus, int devfn, int where)
  37 {
  38         struct pci_sys_data *sys = bus->sysdata;
  39         u32 addr;
  40
  41         if (sys->busnr == bus->number)
  42                 addr = 1 << (PCI_SLOT(devfn) + 16) | (PCI_SLOT(devfn) << 11);
  43         else
  44                 addr = bus->number << 16 | PCI_SLOT(devfn) << 11 | 1;
  45
  46         addr |= PCI_FUNC(devfn) << 8 | (where & ~3);
  47
  48         return addr;
  49 }
  50
  51 /*
  52  * This routine checks the status of the last configuration cycle.  If an error
  53  * was detected it returns a 1, else it returns a 0.  The errors being checked
  54  * are parity, master abort, target abort (master and target).  These types of
  55  * errors occur during a config cycle where there is no device, like during
  56  * the discovery stage.
  57  */
  58 static int iop3xx_pci_status(void)
  59 {
  60         unsigned int status;
  61         int ret = 0;
  62
  63         /*
  64          * Check the status registers.
  65          */
  66         status = *IOP3XX_ATUSR;
  67         if (status & 0xf900) {
  68                 DBG("\t\t\tPCI: P0 - status = 0x%08x\n", status);
  69                 *IOP3XX_ATUSR = status & 0xf900;
  70                 ret = 1;
  71         }
  72
  73         status = *IOP3XX_ATUISR;
  74         if (status & 0x679f) {
  75                 DBG("\t\t\tPCI: P1 - status = 0x%08x\n", status);
  76                 *IOP3XX_ATUISR = status & 0x679f;
  77                 ret = 1;
  78         }
  79
  80         return ret;
  81 }
  82
  83 /*
  84  * Simply write the address register and read the configuration
  85  * data.  Note that the 4 nops ensure that we are able to handle
  86  * a delayed abort (in theory.)
  87  */
  88 static u32 iop3xx_read(unsigned long addr)
  89 {
  90         u32 val;
  91
  92         __asm__ __volatile__(
  93                 "str    %1, [%2]\n\t"
  94                 "ldr    %0, [%3]\n\t"
  95                 "nop\n\t"
  96                 "nop\n\t"
  97                 "nop\n\t"
  98                 "nop\n\t"
  99                 : "=r" (val)
 100                 : "r" (addr), "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
 101
 102         return val;
 103 }
 104
 105 /*
 106  * The read routines must check the error status of the last configuration
 107  * cycle.  If there was an error, the routine returns all hex f's.
 108  */
 109 static int
 110 iop3xx_read_config(struct pci_bus *bus, unsigned int devfn, int where,
 111                 int size, u32 *value)
 112 {
 113         unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
 114         u32 val = iop3xx_read(addr) >> ((where & 3) * 8);
 115
 116         if (iop3xx_pci_status())
 117                 val = 0xffffffff;
 118
 119         *value = val;
 120
 121         return PCIBIOS_SUCCESSFUL;
 122 }
 123
 124 static int
 125 iop3xx_write_config(struct pci_bus *bus, unsigned int devfn, int where,
 126                 int size, u32 value)
 127 {
 128         unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
 129         u32 val;
 130
 131         if (size != 4) {
 132                 val = iop3xx_read(addr);
 133                 if (iop3xx_pci_status())
 134                         return PCIBIOS_SUCCESSFUL;
 135
 136                 where = (where & 3) * 8;
 137
 138                 if (size == 1)
 139                         val &= ~(0xff << where);
 140                 else
 141                         val &= ~(0xffff << where);
 142
 143                 *IOP3XX_OCCDR = val | value << where;
 144         } else {
 145                 asm volatile(
 146                         "str    %1, [%2]\n\t"
 147                         "str    %0, [%3]\n\t"
 148                         "nop\n\t"
 149                         "nop\n\t"
 150                         "nop\n\t"
 151                         "nop\n\t"
 152                         :
 153                         : "r" (value), "r" (addr),
 154                           "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
 155         }
 156
 157         return PCIBIOS_SUCCESSFUL;
 158 }
 159
 160 struct pci_ops iop3xx_ops = {
 161         .read   = iop3xx_read_config,
 162         .write  = iop3xx_write_config,
 163 };
 164
 165 /*
 166  * When a PCI device does not exist during config cycles, the 80200 gets a
 167  * bus error instead of returning 0xffffffff. This handler simply returns.
 168  */
 169 static int
 170 iop3xx_pci_abort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 171 {
 172         DBG("PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx\n",
 173                 addr, fsr, regs->ARM_pc, regs->ARM_lr);
 174
 175         /*
 176          * If it was an imprecise abort, then we need to correct the
 177          * return address to be _after_ the instruction.
 178          */
 179         if (fsr & (1 << 10))
 180                 regs->ARM_pc += 4;
 181
 182         return 0;
 183 }
 184
 185 int iop3xx_pci_setup(int nr, struct pci_sys_data *sys)
 186 {
 187         struct resource *res;
 188
 189         if (nr != 0)
 190                 return 0;
 191
 192         res = kzalloc(sizeof(struct resource), GFP_KERNEL);
 193         if (!res)
 194                 panic("PCI: unable to alloc resources");
 195
 196         res->start = IOP3XX_PCI_LOWER_MEM_PA;
 197         res->end   = IOP3XX_PCI_LOWER_MEM_PA + IOP3XX_PCI_MEM_WINDOW_SIZE - 1;
 198         res->name  = "IOP3XX PCI Memory Space";
 199         res->flags = IORESOURCE_MEM;
 200         request_resource(&iomem_resource, res);
 201
 202         /*
 203          * Use whatever translation is already setup.
 204          */
 205         sys->mem_offset = IOP3XX_PCI_LOWER_MEM_PA - *IOP3XX_OMWTVR0;
 206
 207         pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
 208
 209         pci_ioremap_io(0, IOP3XX_PCI_LOWER_IO_PA);
 210
 211         return 1;
 212 }
 213
 214 void __init iop3xx_atu_setup(void)
 215 {
 216         /* BAR 0 ( Disabled ) */
 217         *IOP3XX_IAUBAR0 = 0x0;
 218         *IOP3XX_IABAR0  = 0x0;
 219         *IOP3XX_IATVR0  = 0x0;
 220         *IOP3XX_IALR0   = 0x0;
 221
 222         /* BAR 1 ( Disabled ) */
 223         *IOP3XX_IAUBAR1 = 0x0;
 224         *IOP3XX_IABAR1  = 0x0;
 225         *IOP3XX_IALR1   = 0x0;
 226
 227         /* BAR 2 (1:1 mapping with Physical RAM) */
 228         /* Set limit and enable */
 229         *IOP3XX_IALR2 = ~((u32)IOP3XX_MAX_RAM_SIZE - 1) & ~0x1;
 230         *IOP3XX_IAUBAR2 = 0x0;
 231
 232         /* Align the inbound bar with the base of memory */
 233         *IOP3XX_IABAR2 = PHYS_OFFSET |
 234                                PCI_BASE_ADDRESS_MEM_TYPE_64 |
 235                                PCI_BASE_ADDRESS_MEM_PREFETCH;
 236
 237         *IOP3XX_IATVR2 = PHYS_OFFSET;
 238
 239         /* Outbound window 0 */
 240         *IOP3XX_OMWTVR0 = IOP3XX_PCI_LOWER_MEM_BA;
 241         *IOP3XX_OUMWTVR0 = 0;
 242
 243         /* Outbound window 1 */
 244         *IOP3XX_OMWTVR1 = IOP3XX_PCI_LOWER_MEM_BA +
 245                           IOP3XX_PCI_MEM_WINDOW_SIZE / 2;
 246         *IOP3XX_OUMWTVR1 = 0;
 247
 248         /* BAR 3 ( Disabled ) */
 249         *IOP3XX_IAUBAR3 = 0x0;
 250         *IOP3XX_IABAR3  = 0x0;
 251         *IOP3XX_IATVR3  = 0x0;
 252         *IOP3XX_IALR3   = 0x0;
 253
 254         /* Setup the I/O Bar
 255          */
 256         *IOP3XX_OIOWTVR = IOP3XX_PCI_LOWER_IO_BA;
 257
 258         /* Enable inbound and outbound cycles
 259          */
 260         *IOP3XX_ATUCMD |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
 261                                PCI_COMMAND_PARITY | PCI_COMMAND_SERR;
 262         *IOP3XX_ATUCR |= IOP3XX_ATUCR_OUT_EN;
 263 }
 264
 265 void __init iop3xx_atu_disable(void)
 266 {
 267         *IOP3XX_ATUCMD = 0;
 268         *IOP3XX_ATUCR = 0;
 269
 270         /* wait for cycles to quiesce */
 271         while (*IOP3XX_PCSR & (IOP3XX_PCSR_OUT_Q_BUSY |
 272                                      IOP3XX_PCSR_IN_Q_BUSY))
 273                 cpu_relax();
 274
 275         /* BAR 0 ( Disabled ) */
 276         *IOP3XX_IAUBAR0 = 0x0;
 277         *IOP3XX_IABAR0  = 0x0;
 278         *IOP3XX_IATVR0  = 0x0;
 279         *IOP3XX_IALR0   = 0x0;
 280
 281         /* BAR 1 ( Disabled ) */
 282         *IOP3XX_IAUBAR1 = 0x0;
 283         *IOP3XX_IABAR1  = 0x0;
 284         *IOP3XX_IALR1   = 0x0;
 285
 286         /* BAR 2 ( Disabled ) */
 287         *IOP3XX_IAUBAR2 = 0x0;
 288         *IOP3XX_IABAR2  = 0x0;
 289         *IOP3XX_IATVR2  = 0x0;
 290         *IOP3XX_IALR2   = 0x0;
 291
 292         /* BAR 3 ( Disabled ) */
 293         *IOP3XX_IAUBAR3 = 0x0;
 294         *IOP3XX_IABAR3  = 0x0;
 295         *IOP3XX_IATVR3  = 0x0;
 296         *IOP3XX_IALR3   = 0x0;
 297
 298         /* Clear the outbound windows */
 299         *IOP3XX_OIOWTVR  = 0;
 300
 301         /* Outbound window 0 */
 302         *IOP3XX_OMWTVR0 = 0;
 303         *IOP3XX_OUMWTVR0 = 0;
 304
 305         /* Outbound window 1 */
 306         *IOP3XX_OMWTVR1 = 0;
 307         *IOP3XX_OUMWTVR1 = 0;
 308 }
 309
 310 /* Flag to determine whether the ATU is initialized and the PCI bus scanned */
 311 int init_atu;
 312
 313 int iop3xx_get_init_atu(void) {
 314         /* check if default has been overridden */
 315         if (init_atu != IOP3XX_INIT_ATU_DEFAULT)
 316                 return init_atu;
 317         else
 318                 return IOP3XX_INIT_ATU_DISABLE;
 319 }
 320
 321 static void __init iop3xx_atu_debug(void)
 322 {
 323         DBG("PCI: Intel IOP3xx PCI init.\n");
 324         DBG("PCI: Outbound memory window 0: PCI 0x%08x%08x\n",
 325                 *IOP3XX_OUMWTVR0, *IOP3XX_OMWTVR0);
 326         DBG("PCI: Outbound memory window 1: PCI 0x%08x%08x\n",
 327                 *IOP3XX_OUMWTVR1, *IOP3XX_OMWTVR1);
 328         DBG("PCI: Outbound IO window: PCI 0x%08x\n",
 329                 *IOP3XX_OIOWTVR);
 330
 331         DBG("PCI: Inbound memory window 0: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
 332                 *IOP3XX_IAUBAR0, *IOP3XX_IABAR0, *IOP3XX_IALR0, *IOP3XX_IATVR0);
 333         DBG("PCI: Inbound memory window 1: PCI 0x%08x%08x 0x%08x\n",
 334                 *IOP3XX_IAUBAR1, *IOP3XX_IABAR1, *IOP3XX_IALR1);
 335         DBG("PCI: Inbound memory window 2: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
 336                 *IOP3XX_IAUBAR2, *IOP3XX_IABAR2, *IOP3XX_IALR2, *IOP3XX_IATVR2);
 337         DBG("PCI: Inbound memory window 3: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
 338                 *IOP3XX_IAUBAR3, *IOP3XX_IABAR3, *IOP3XX_IALR3, *IOP3XX_IATVR3);
 339
 340         DBG("PCI: Expansion ROM window: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
 341                 0, *IOP3XX_ERBAR, *IOP3XX_ERLR, *IOP3XX_ERTVR);
 342
 343         DBG("ATU: IOP3XX_ATUCMD=0x%04x\n", *IOP3XX_ATUCMD);
 344         DBG("ATU: IOP3XX_ATUCR=0x%08x\n", *IOP3XX_ATUCR);
 345
 346         hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, 0, "imprecise external abort");
 347 }
 348
 349 /* for platforms that might be host-bus-adapters */
 350 void __init iop3xx_pci_preinit_cond(void)
 351 {
 352         if (iop3xx_get_init_atu() == IOP3XX_INIT_ATU_ENABLE) {
 353                 iop3xx_atu_disable();
 354                 iop3xx_atu_setup();
 355                 iop3xx_atu_debug();
 356         }
 357 }
 358
 359 void __init iop3xx_pci_preinit(void)
 360 {
 361         pcibios_min_mem = 0;
 362
 363         iop3xx_atu_disable();
 364         iop3xx_atu_setup();
 365         iop3xx_atu_debug();
 366 }
 367
 368 /* allow init_atu to be user overridden */
 369 static int __init iop3xx_init_atu_setup(char *str)
 370 {
 371         init_atu = IOP3XX_INIT_ATU_DEFAULT;
 372         if (str) {
 373                 while (*str != '\0') {
 374                         switch (*str) {
 375                         case 'y':
 376                         case 'Y':
 377                                 init_atu = IOP3XX_INIT_ATU_ENABLE;
 378                                 break;
 379                         case 'n':
 380                         case 'N':
 381                                 init_atu = IOP3XX_INIT_ATU_DISABLE;
 382                                 break;
 383                         case ',':
 384                         case '=':
 385                                 break;
 386                         default:
 387                                 printk(KERN_DEBUG "\"%s\" malformed at "
 388                                             "character: \'%c\'",
 389                                             __func__,
 390                                             *str);
 391                                 *(str + 1) = '\0';
 392                         }
 393                         str++;
 394                 }
 395         }
 396
 397         return 1;
 398 }
 399
 400 __setup("iop3xx_init_atu", iop3xx_init_atu_setup);
 401