arch/mips/pci/ops-bonito64.c

   1 /*
   2  * Copyright (C) 1999, 2000, 2004  MIPS Technologies, Inc.
   3  *      All rights reserved.
   4  *      Authors: Carsten Langgaard <carstenl@mips.com>
   5  *               Maciej W. Rozycki <macro@mips.com>
   6  *
   7  *  This program is free software; you can distribute it and/or modify it
   8  *  under the terms of the GNU General Public License (Version 2) as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope it will be useful, but WITHOUT
  12  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  *  for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License along
  17  *  with this program; if not, write to the Free Software Foundation, Inc.,
  18  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  19  *
  20  * MIPS boards specific PCI support.
  21  */
  22 #include <linux/types.h>
  23 #include <linux/pci.h>
  24 #include <linux/kernel.h>
  25 #include <linux/init.h>
  26
  27 #include <asm/mips-boards/bonito64.h>
  28
  29 #define PCI_ACCESS_READ  0
  30 #define PCI_ACCESS_WRITE 1
  31
  32 /*
  33  *  PCI configuration cycle AD bus definition
  34  */
  35 /* Type 0 */
  36 #define PCI_CFG_TYPE0_REG_SHF           0
  37 #define PCI_CFG_TYPE0_FUNC_SHF          8
  38
  39 /* Type 1 */
  40 #define PCI_CFG_TYPE1_REG_SHF           0
  41 #define PCI_CFG_TYPE1_FUNC_SHF          8
  42 #define PCI_CFG_TYPE1_DEV_SHF           11
  43 #define PCI_CFG_TYPE1_BUS_SHF           16
  44
  45 static int bonito64_pcibios_config_access(unsigned char access_type,
  46                                       struct pci_bus *bus,
  47                                       unsigned int devfn, int where,
  48                                       u32 * data)
  49 {
  50         unsigned char busnum = bus->number;
  51         u32 dummy;
  52         u64 pci_addr;
  53
  54         /* Algorithmics Bonito64 system controller. */
  55
  56         if ((busnum == 0) && (PCI_SLOT(devfn) > 21)) {
  57                 /* We number bus 0 devices from 0..21 */
  58                 return -1;
  59         }
  60
  61         /* Clear cause register bits */
  62         BONITO_PCICMD |= (BONITO_PCICMD_MABORT_CLR |
  63                           BONITO_PCICMD_MTABORT_CLR);
  64
  65         /*
  66          * Setup pattern to be used as PCI "address" for
  67          * Type 0 cycle
  68          */
  69         if (busnum == 0) {
  70                 /* IDSEL */
  71                 pci_addr = (u64) 1 << (PCI_SLOT(devfn) + 10);
  72         } else {
  73                 /* Bus number */
  74                 pci_addr = busnum << PCI_CFG_TYPE1_BUS_SHF;
  75
  76                 /* Device number */
  77                 pci_addr |=
  78                     PCI_SLOT(devfn) << PCI_CFG_TYPE1_DEV_SHF;
  79         }
  80
  81         /* Function (same for Type 0/1) */
  82         pci_addr |= PCI_FUNC(devfn) << PCI_CFG_TYPE0_FUNC_SHF;
  83
  84         /* Register number (same for Type 0/1) */
  85         pci_addr |= (where & ~0x3) << PCI_CFG_TYPE0_REG_SHF;
  86
  87         if (busnum == 0) {
  88                 /* Type 0 */
  89                 BONITO_PCIMAP_CFG = pci_addr >> 16;
  90         } else {
  91                 /* Type 1 */
  92                 BONITO_PCIMAP_CFG = (pci_addr >> 16) | 0x10000;
  93         }
  94
  95         pci_addr &= 0xffff;
  96
  97         /* Flush Bonito register block */
  98         dummy = BONITO_PCIMAP_CFG;
  99         iob();          /* sync */
 100
 101         /* Perform access */
 102         if (access_type == PCI_ACCESS_WRITE) {
 103                 *(volatile u32 *) (_pcictrl_bonito_pcicfg + (u32)pci_addr) = *(u32 *) data;
 104
 105                 /* Wait till done */
 106                 while (BONITO_PCIMSTAT & 0xF);
 107         } else {
 108                 *(u32 *) data = *(volatile u32 *) (_pcictrl_bonito_pcicfg + (u32)pci_addr);
 109         }
 110
 111         /* Detect Master/Target abort */
 112         if (BONITO_PCICMD & (BONITO_PCICMD_MABORT_CLR |
 113                              BONITO_PCICMD_MTABORT_CLR)) {
 114                 /* Error occurred */
 115
 116                 /* Clear bits */
 117                 BONITO_PCICMD |= (BONITO_PCICMD_MABORT_CLR |
 118                                   BONITO_PCICMD_MTABORT_CLR);
 119
 120                 return -1;
 121         }
 122
 123         return 0;
 124 }
 125
 126
 127 /*
 128  * We can't address 8 and 16 bit words directly.  Instead we have to
 129  * read/write a 32bit word and mask/modify the data we actually want.
 130  */
 131 static int bonito64_pcibios_read(struct pci_bus *bus, unsigned int devfn,
 132                              int where, int size, u32 * val)
 133 {
 134         u32 data = 0;
 135
 136         if ((size == 2) && (where & 1))
 137                 return PCIBIOS_BAD_REGISTER_NUMBER;
 138         else if ((size == 4) && (where & 3))
 139                 return PCIBIOS_BAD_REGISTER_NUMBER;
 140
 141         if (bonito64_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
 142                                        &data))
 143                 return -1;
 144
 145         if (size == 1)
 146                 *val = (data >> ((where & 3) << 3)) & 0xff;
 147         else if (size == 2)
 148                 *val = (data >> ((where & 3) << 3)) & 0xffff;
 149         else
 150                 *val = data;
 151
 152         return PCIBIOS_SUCCESSFUL;
 153 }
 154
 155 static int bonito64_pcibios_write(struct pci_bus *bus, unsigned int devfn,
 156                               int where, int size, u32 val)
 157 {
 158         u32 data = 0;
 159
 160         if ((size == 2) && (where & 1))
 161                 return PCIBIOS_BAD_REGISTER_NUMBER;
 162         else if ((size == 4) && (where & 3))
 163                 return PCIBIOS_BAD_REGISTER_NUMBER;
 164
 165         if (size == 4)
 166                 data = val;
 167         else {
 168                 if (bonito64_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
 169                                                where, &data))
 170                         return -1;
 171
 172                 if (size == 1)
 173                         data = (data & ~(0xff << ((where & 3) << 3))) |
 174                                 (val << ((where & 3) << 3));
 175                 else if (size == 2)
 176                         data = (data & ~(0xffff << ((where & 3) << 3))) |
 177                                 (val << ((where & 3) << 3));
 178         }
 179
 180         if (bonito64_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
 181                                        &data))
 182                 return -1;
 183
 184         return PCIBIOS_SUCCESSFUL;
 185 }
 186
 187 struct pci_ops bonito64_pci_ops = {
 188         .read = bonito64_pcibios_read,
 189         .write = bonito64_pcibios_write
 190 };