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