arch/mips/pci/ops-loongson2.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  * Copyright (C) 2009 Lemote Inc.
   8  * Author: Wu Zhangjin <wuzhangjin@gmail.com>
   9  *
  10  *  This program is free software; you can distribute it and/or modify it
  11  *  under the terms of the GNU General Public License (Version 2) as
  12  *  published by the Free Software Foundation.
  13  */
  14 #include <linux/types.h>
  15 #include <linux/pci.h>
  16 #include <linux/kernel.h>
  17 #include <linux/export.h>
  18
  19 #include <loongson.h>
  20
  21 #ifdef CONFIG_CS5536
  22 #include <cs5536/cs5536_pci.h>
  23 #include <cs5536/cs5536.h>
  24 #endif
  25
  26 #define PCI_ACCESS_READ  0
  27 #define PCI_ACCESS_WRITE 1
  28
  29 #define CFG_SPACE_REG(offset) \
  30         (void *)CKSEG1ADDR(LOONGSON_PCICFG_BASE | (offset))
  31 #define ID_SEL_BEGIN 11
  32 #define MAX_DEV_NUM (31 - ID_SEL_BEGIN)
  33
  34
  35 static int loongson_pcibios_config_access(unsigned char access_type,
  36                                       struct pci_bus *bus,
  37                                       unsigned int devfn, int where,
  38                                       u32 *data)
  39 {
  40         u32 busnum = bus->number;
  41         u32 addr, type;
  42         u32 dummy;
  43         void *addrp;
  44         int device = PCI_SLOT(devfn);
  45         int function = PCI_FUNC(devfn);
  46         int reg = where & ~3;
  47
  48         if (busnum == 0) {
  49                 /* board-specific part,currently,only fuloong2f,yeeloong2f
  50                  * use CS5536, fuloong2e use via686b, gdium has no
  51                  * south bridge
  52                  */
  53 #ifdef CONFIG_CS5536
  54                 /* cs5536_pci_conf_read4/write4() will call _rdmsr/_wrmsr() to
  55                  * access the regsters PCI_MSR_ADDR, PCI_MSR_DATA_LO,
  56                  * PCI_MSR_DATA_HI, which is bigger than PCI_MSR_CTRL, so, it
  57                  * will not go this branch, but the others. so, no calling dead
  58                  * loop here.
  59                  */
  60                 if ((PCI_IDSEL_CS5536 == device) && (reg < PCI_MSR_CTRL)) {
  61                         switch (access_type) {
  62                         case PCI_ACCESS_READ:
  63                                 *data = cs5536_pci_conf_read4(function, reg);
  64                                 break;
  65                         case PCI_ACCESS_WRITE:
  66                                 cs5536_pci_conf_write4(function, reg, *data);
  67                                 break;
  68                         }
  69                         return 0;
  70                 }
  71 #endif
  72                 /* Type 0 configuration for onboard PCI bus */
  73                 if (device > MAX_DEV_NUM)
  74                         return -1;
  75
  76                 addr = (1 << (device + ID_SEL_BEGIN)) | (function << 8) | reg;
  77                 type = 0;
  78         } else {
  79                 /* Type 1 configuration for offboard PCI bus */
  80                 addr = (busnum << 16) | (device << 11) | (function << 8) | reg;
  81                 type = 0x10000;
  82         }
  83
  84         /* Clear aborts */
  85         LOONGSON_PCICMD |= LOONGSON_PCICMD_MABORT_CLR | \
  86                                 LOONGSON_PCICMD_MTABORT_CLR;
  87
  88         LOONGSON_PCIMAP_CFG = (addr >> 16) | type;
  89
  90         /* Flush Bonito register block */
  91         dummy = LOONGSON_PCIMAP_CFG;
  92         mmiowb();
  93
  94         addrp = CFG_SPACE_REG(addr & 0xffff);
  95         if (access_type == PCI_ACCESS_WRITE)
  96                 writel(cpu_to_le32(*data), addrp);
  97         else
  98                 *data = le32_to_cpu(readl(addrp));
  99
 100         /* Detect Master/Target abort */
 101         if (LOONGSON_PCICMD & (LOONGSON_PCICMD_MABORT_CLR |
 102                              LOONGSON_PCICMD_MTABORT_CLR)) {
 103                 /* Error occurred */
 104
 105                 /* Clear bits */
 106                 LOONGSON_PCICMD |= (LOONGSON_PCICMD_MABORT_CLR |
 107                                   LOONGSON_PCICMD_MTABORT_CLR);
 108
 109                 return -1;
 110         }
 111
 112         return 0;
 113
 114 }
 115
 116
 117 /*
 118  * We can't address 8 and 16 bit words directly.  Instead we have to
 119  * read/write a 32bit word and mask/modify the data we actually want.
 120  */
 121 static int loongson_pcibios_read(struct pci_bus *bus, unsigned int devfn,
 122                              int where, int size, u32 *val)
 123 {
 124         u32 data = 0;
 125
 126         if ((size == 2) && (where & 1))
 127                 return PCIBIOS_BAD_REGISTER_NUMBER;
 128         else if ((size == 4) && (where & 3))
 129                 return PCIBIOS_BAD_REGISTER_NUMBER;
 130
 131         if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
 132                                        &data))
 133                 return -1;
 134
 135         if (size == 1)
 136                 *val = (data >> ((where & 3) << 3)) & 0xff;
 137         else if (size == 2)
 138                 *val = (data >> ((where & 3) << 3)) & 0xffff;
 139         else
 140                 *val = data;
 141
 142         return PCIBIOS_SUCCESSFUL;
 143 }
 144
 145 static int loongson_pcibios_write(struct pci_bus *bus, unsigned int devfn,
 146                               int where, int size, u32 val)
 147 {
 148         u32 data = 0;
 149
 150         if ((size == 2) && (where & 1))
 151                 return PCIBIOS_BAD_REGISTER_NUMBER;
 152         else if ((size == 4) && (where & 3))
 153                 return PCIBIOS_BAD_REGISTER_NUMBER;
 154
 155         if (size == 4)
 156                 data = val;
 157         else {
 158                 if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
 159                                         where, &data))
 160                         return -1;
 161
 162                 if (size == 1)
 163                         data = (data & ~(0xff << ((where & 3) << 3))) |
 164                                 (val << ((where & 3) << 3));
 165                 else if (size == 2)
 166                         data = (data & ~(0xffff << ((where & 3) << 3))) |
 167                                 (val << ((where & 3) << 3));
 168         }
 169
 170         if (loongson_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
 171                                        &data))
 172                 return -1;
 173
 174         return PCIBIOS_SUCCESSFUL;
 175 }
 176
 177 struct pci_ops loongson_pci_ops = {
 178         .read = loongson_pcibios_read,
 179         .write = loongson_pcibios_write
 180 };
 181
 182 #ifdef CONFIG_CS5536
 183 DEFINE_RAW_SPINLOCK(msr_lock);
 184
 185 void _rdmsr(u32 msr, u32 *hi, u32 *lo)
 186 {
 187         struct pci_bus bus = {
 188                 .number = PCI_BUS_CS5536
 189         };
 190         u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
 191         unsigned long flags;
 192
 193         raw_spin_lock_irqsave(&msr_lock, flags);
 194         loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
 195         loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
 196         loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
 197         raw_spin_unlock_irqrestore(&msr_lock, flags);
 198 }
 199 EXPORT_SYMBOL(_rdmsr);
 200
 201 void _wrmsr(u32 msr, u32 hi, u32 lo)
 202 {
 203         struct pci_bus bus = {
 204                 .number = PCI_BUS_CS5536
 205         };
 206         u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
 207         unsigned long flags;
 208
 209         raw_spin_lock_irqsave(&msr_lock, flags);
 210         loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
 211         loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
 212         loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
 213         raw_spin_unlock_irqrestore(&msr_lock, flags);
 214 }
 215 EXPORT_SYMBOL(_wrmsr);
 216 #endif