arch/mips/pci/ops-ddb5477.c

   1 /***********************************************************************
   2  * Copyright 2001 MontaVista Software Inc.
   3  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
   4  *
   5  * arch/mips/ddb5xxx/ddb5477/pci_ops.c
   6  *     Define the pci_ops for DB5477.
   7  *
   8  * Much of the code is derived from the original DDB5074 port by
   9  * Geert Uytterhoeven <geert@sonycom.com>
  10  *
  11  * This program is free software; you can redistribute  it and/or modify it
  12  * under  the terms of  the GNU General  Public License as published by the
  13  * Free Software Foundation;  either version 2 of the  License, or (at your
  14  * option) any later version.
  15  ***********************************************************************
  16  */
  17
  18 /*
  19  * DDB5477 has two PCI channels, external PCI and IOPIC (internal)
  20  * Therefore we provide two sets of pci_ops.
  21  */
  22 #include <linux/pci.h>
  23 #include <linux/kernel.h>
  24 #include <linux/types.h>
  25
  26 #include <asm/addrspace.h>
  27 #include <asm/debug.h>
  28
  29 #include <asm/ddb5xxx/ddb5xxx.h>
  30
  31 /*
  32  * config_swap structure records what set of pdar/pmr are used
  33  * to access pci config space.  It also provides a place hold the
  34  * original values for future restoring.
  35  */
  36 struct pci_config_swap {
  37         u32 pdar;
  38         u32 pmr;
  39         u32 config_base;
  40         u32 config_size;
  41         u32 pdar_backup;
  42         u32 pmr_backup;
  43 };
  44
  45 /*
  46  * On DDB5477, we have two sets of swap registers, for ext PCI and IOPCI.
  47  */
  48 struct pci_config_swap ext_pci_swap = {
  49         DDB_PCIW0,
  50         DDB_PCIINIT00,
  51         DDB_PCI0_CONFIG_BASE,
  52         DDB_PCI0_CONFIG_SIZE
  53 };
  54 struct pci_config_swap io_pci_swap = {
  55         DDB_IOPCIW0,
  56         DDB_PCIINIT01,
  57         DDB_PCI1_CONFIG_BASE,
  58         DDB_PCI1_CONFIG_SIZE
  59 };
  60
  61
  62 /*
  63  * access config space
  64  */
  65 static inline u32 ddb_access_config_base(struct pci_config_swap *swap, u32 bus, /* 0 means top level bus */
  66                                          u32 slot_num)
  67 {
  68         u32 pci_addr = 0;
  69         u32 pciinit_offset = 0;
  70         u32 virt_addr;
  71         u32 option;
  72
  73         /* minimum pdar (window) size is 2MB */
  74         db_assert(swap->config_size >= (2 << 20));
  75
  76         db_assert(slot_num < (1 << 5));
  77         db_assert(bus < (1 << 8));
  78
  79         /* backup registers */
  80         swap->pdar_backup = ddb_in32(swap->pdar);
  81         swap->pmr_backup = ddb_in32(swap->pmr);
  82
  83         /* set the pdar (pci window) register */
  84         ddb_set_pdar(swap->pdar, swap->config_base, swap->config_size, 32,      /* 32 bit wide */
  85                      0,         /* not on local memory bus */
  86                      0);        /* not visible from PCI bus (N/A) */
  87
  88         /*
  89          * calcuate the absolute pci config addr;
  90          * according to the spec, we start scanning from adr:11 (0x800)
  91          */
  92         if (bus == 0) {
  93                 /* type 0 config */
  94                 pci_addr = 0x800 << slot_num;
  95         } else {
  96                 /* type 1 config */
  97                 pci_addr = (bus << 16) | (slot_num << 11);
  98         }
  99
 100         /*
 101          * if pci_addr is less than pci config window size,  we set
 102          * pciinit_offset to 0 and adjust the virt_address.
 103          * Otherwise we will try to adjust pciinit_offset.
 104          */
 105         if (pci_addr < swap->config_size) {
 106                 virt_addr = KSEG1ADDR(swap->config_base + pci_addr);
 107                 pciinit_offset = 0;
 108         } else {
 109                 db_assert((pci_addr & (swap->config_size - 1)) == 0);
 110                 virt_addr = KSEG1ADDR(swap->config_base);
 111                 pciinit_offset = pci_addr;
 112         }
 113
 114         /* set the pmr register */
 115         option = DDB_PCI_ACCESS_32;
 116         if (bus != 0)
 117                 option |= DDB_PCI_CFGTYPE1;
 118         ddb_set_pmr(swap->pmr, DDB_PCICMD_CFG, pciinit_offset, option);
 119
 120         return virt_addr;
 121 }
 122
 123 static inline void ddb_close_config_base(struct pci_config_swap *swap)
 124 {
 125         ddb_out32(swap->pdar, swap->pdar_backup);
 126         ddb_out32(swap->pmr, swap->pmr_backup);
 127 }
 128
 129 static int read_config_dword(struct pci_config_swap *swap,
 130                              struct pci_bus *bus, u32 devfn, u32 where,
 131                              u32 * val)
 132 {
 133         u32 bus_num, slot_num, func_num;
 134         u32 base;
 135
 136         db_assert((where & 3) == 0);
 137         db_assert(where < (1 << 8));
 138
 139         /* check if the bus is top-level */
 140         if (bus->parent != NULL) {
 141                 bus_num = bus->number;
 142                 db_assert(bus_num != 0);
 143         } else {
 144                 bus_num = 0;
 145         }
 146
 147         slot_num = PCI_SLOT(devfn);
 148         func_num = PCI_FUNC(devfn);
 149         base = ddb_access_config_base(swap, bus_num, slot_num);
 150         *val = *(volatile u32 *) (base + (func_num << 8) + where);
 151         ddb_close_config_base(swap);
 152         return PCIBIOS_SUCCESSFUL;
 153 }
 154
 155 static int read_config_word(struct pci_config_swap *swap,
 156                             struct pci_bus *bus, u32 devfn, u32 where,
 157                             u16 * val)
 158 {
 159         int status;
 160         u32 result;
 161
 162         db_assert((where & 1) == 0);
 163
 164         status = read_config_dword(swap, bus, devfn, where & ~3, &result);
 165         if (where & 2)
 166                 result >>= 16;
 167         *val = result & 0xffff;
 168         return status;
 169 }
 170
 171 static int read_config_byte(struct pci_config_swap *swap,
 172                             struct pci_bus *bus, u32 devfn, u32 where,
 173                             u8 * val)
 174 {
 175         int status;
 176         u32 result;
 177
 178         status = read_config_dword(swap, bus, devfn, where & ~3, &result);
 179         if (where & 1)
 180                 result >>= 8;
 181         if (where & 2)
 182                 result >>= 16;
 183         *val = result & 0xff;
 184
 185         return status;
 186 }
 187
 188 static int write_config_dword(struct pci_config_swap *swap,
 189                               struct pci_bus *bus, u32 devfn, u32 where,
 190                               u32 val)
 191 {
 192         u32 bus_num, slot_num, func_num;
 193         u32 base;
 194
 195         db_assert((where & 3) == 0);
 196         db_assert(where < (1 << 8));
 197
 198         /* check if the bus is top-level */
 199         if (bus->parent != NULL) {
 200                 bus_num = bus->number;
 201                 db_assert(bus_num != 0);
 202         } else {
 203                 bus_num = 0;
 204         }
 205
 206         slot_num = PCI_SLOT(devfn);
 207         func_num = PCI_FUNC(devfn);
 208         base = ddb_access_config_base(swap, bus_num, slot_num);
 209         *(volatile u32 *) (base + (func_num << 8) + where) = val;
 210         ddb_close_config_base(swap);
 211         return PCIBIOS_SUCCESSFUL;
 212 }
 213
 214 static int write_config_word(struct pci_config_swap *swap,
 215                              struct pci_bus *bus, u32 devfn, u32 where, u16 val)
 216 {
 217         int status, shift = 0;
 218         u32 result;
 219
 220         db_assert((where & 1) == 0);
 221
 222         status = read_config_dword(swap, bus, devfn, where & ~3, &result);
 223         if (status != PCIBIOS_SUCCESSFUL)
 224                 return status;
 225
 226         if (where & 2)
 227                 shift += 16;
 228         result &= ~(0xffff << shift);
 229         result |= val << shift;
 230         return write_config_dword(swap, bus, devfn, where & ~3, result);
 231 }
 232
 233 static int write_config_byte(struct pci_config_swap *swap,
 234                              struct pci_bus *bus, u32 devfn, u32 where, u8 val)
 235 {
 236         int status, shift = 0;
 237         u32 result;
 238
 239         status = read_config_dword(swap, bus, devfn, where & ~3, &result);
 240         if (status != PCIBIOS_SUCCESSFUL)
 241                 return status;
 242
 243         if (where & 2)
 244                 shift += 16;
 245         if (where & 1)
 246                 shift += 8;
 247         result &= ~(0xff << shift);
 248         result |= val << shift;
 249         return write_config_dword(swap, bus, devfn, where & ~3, result);
 250 }
 251
 252 #define        MAKE_PCI_OPS(prefix, rw, pciswap, star) \
 253 static int prefix##_##rw##_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 star val) \
 254 { \
 255         if (size == 1) \
 256                 return rw##_config_byte(pciswap, bus, devfn, where, (u8 star)val); \
 257         else if (size == 2) \
 258                 return rw##_config_word(pciswap, bus, devfn, where, (u16 star)val); \
 259         /* Size must be 4 */ \
 260         return rw##_config_dword(pciswap, bus, devfn, where, val); \
 261 }
 262
 263 MAKE_PCI_OPS(extpci, read, &ext_pci_swap, *)
 264 MAKE_PCI_OPS(extpci, write, &ext_pci_swap,)
 265
 266 MAKE_PCI_OPS(iopci, read, &io_pci_swap, *)
 267 MAKE_PCI_OPS(iopci, write, &io_pci_swap,)
 268
 269 struct pci_ops ddb5477_ext_pci_ops = {
 270         .read = extpci_read_config,
 271         .write = extpci_write_config
 272 };
 273
 274
 275 struct pci_ops ddb5477_io_pci_ops = {
 276         .read = iopci_read_config,
 277         .write = iopci_write_config
 278 };