arch/powerpc/sysdev/indirect_pci.c

   1 /*
   2  * Support for indirect PCI bridges.
   3  *
   4  * Copyright (C) 1998 Gabriel Paubert.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/pci.h>
  14 #include <linux/delay.h>
  15 #include <linux/string.h>
  16 #include <linux/init.h>
  17
  18 #include <asm/io.h>
  19 #include <asm/prom.h>
  20 #include <asm/pci-bridge.h>
  21 #include <asm/machdep.h>
  22
  23 static int
  24 indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
  25                      int len, u32 *val)
  26 {
  27         struct pci_controller *hose = pci_bus_to_host(bus);
  28         volatile void __iomem *cfg_data;
  29         u8 cfg_type = 0;
  30         u32 bus_no, reg;
  31
  32         if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
  33                 if (bus->number != hose->first_busno)
  34                         return PCIBIOS_DEVICE_NOT_FOUND;
  35                 if (devfn != 0)
  36                         return PCIBIOS_DEVICE_NOT_FOUND;
  37         }
  38
  39         if (ppc_md.pci_exclude_device)
  40                 if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
  41                         return PCIBIOS_DEVICE_NOT_FOUND;
  42
  43         if (hose->indirect_type & PPC_INDIRECT_TYPE_SET_CFG_TYPE)
  44                 if (bus->number != hose->first_busno)
  45                         cfg_type = 1;
  46
  47         bus_no = (bus->number == hose->first_busno) ?
  48                         hose->self_busno : bus->number;
  49
  50         if (hose->indirect_type & PPC_INDIRECT_TYPE_EXT_REG)
  51                 reg = ((offset & 0xf00) << 16) | (offset & 0xfc);
  52         else
  53                 reg = offset & 0xfc;
  54
  55         if (hose->indirect_type & PPC_INDIRECT_TYPE_BIG_ENDIAN)
  56                 out_be32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  57                          (devfn << 8) | reg | cfg_type));
  58         else
  59                 out_le32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  60                          (devfn << 8) | reg | cfg_type));
  61
  62         /*
  63          * Note: the caller has already checked that offset is
  64          * suitably aligned and that len is 1, 2 or 4.
  65          */
  66         cfg_data = hose->cfg_data + (offset & 3);
  67         switch (len) {
  68         case 1:
  69                 *val = in_8(cfg_data);
  70                 break;
  71         case 2:
  72                 *val = in_le16(cfg_data);
  73                 break;
  74         default:
  75                 *val = in_le32(cfg_data);
  76                 break;
  77         }
  78         return PCIBIOS_SUCCESSFUL;
  79 }
  80
  81 static int
  82 indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
  83                       int len, u32 val)
  84 {
  85         struct pci_controller *hose = pci_bus_to_host(bus);
  86         volatile void __iomem *cfg_data;
  87         u8 cfg_type = 0;
  88         u32 bus_no, reg;
  89
  90         if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
  91                 if (bus->number != hose->first_busno)
  92                         return PCIBIOS_DEVICE_NOT_FOUND;
  93                 if (devfn != 0)
  94                         return PCIBIOS_DEVICE_NOT_FOUND;
  95         }
  96
  97         if (ppc_md.pci_exclude_device)
  98                 if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
  99                         return PCIBIOS_DEVICE_NOT_FOUND;
 100
 101         if (hose->indirect_type & PPC_INDIRECT_TYPE_SET_CFG_TYPE)
 102                 if (bus->number != hose->first_busno)
 103                         cfg_type = 1;
 104
 105         bus_no = (bus->number == hose->first_busno) ?
 106                         hose->self_busno : bus->number;
 107
 108         if (hose->indirect_type & PPC_INDIRECT_TYPE_EXT_REG)
 109                 reg = ((offset & 0xf00) << 16) | (offset & 0xfc);
 110         else
 111                 reg = offset & 0xfc;
 112
 113         if (hose->indirect_type & PPC_INDIRECT_TYPE_BIG_ENDIAN)
 114                 out_be32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
 115                          (devfn << 8) | reg | cfg_type));
 116         else
 117                 out_le32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
 118                          (devfn << 8) | reg | cfg_type));
 119
 120         /* suppress setting of PCI_PRIMARY_BUS */
 121         if (hose->indirect_type & PPC_INDIRECT_TYPE_SURPRESS_PRIMARY_BUS)
 122                 if ((offset == PCI_PRIMARY_BUS) &&
 123                         (bus->number == hose->first_busno))
 124                 val &= 0xffffff00;
 125
 126         /* Workaround for PCI_28 Errata in 440EPx/GRx */
 127         if ((hose->indirect_type & PPC_INDIRECT_TYPE_BROKEN_MRM) &&
 128                         offset == PCI_CACHE_LINE_SIZE) {
 129                 val = 0;
 130         }
 131
 132         /*
 133          * Note: the caller has already checked that offset is
 134          * suitably aligned and that len is 1, 2 or 4.
 135          */
 136         cfg_data = hose->cfg_data + (offset & 3);
 137         switch (len) {
 138         case 1:
 139                 out_8(cfg_data, val);
 140                 break;
 141         case 2:
 142                 out_le16(cfg_data, val);
 143                 break;
 144         default:
 145                 out_le32(cfg_data, val);
 146                 break;
 147         }
 148         return PCIBIOS_SUCCESSFUL;
 149 }
 150
 151 static struct pci_ops indirect_pci_ops =
 152 {
 153         .read = indirect_read_config,
 154         .write = indirect_write_config,
 155 };
 156
 157 void __init
 158 setup_indirect_pci(struct pci_controller* hose,
 159                    resource_size_t cfg_addr,
 160                    resource_size_t cfg_data, u32 flags)
 161 {
 162         resource_size_t base = cfg_addr & PAGE_MASK;
 163         void __iomem *mbase;
 164
 165         mbase = ioremap(base, PAGE_SIZE);
 166         hose->cfg_addr = mbase + (cfg_addr & ~PAGE_MASK);
 167         if ((cfg_data & PAGE_MASK) != base)
 168                 mbase = ioremap(cfg_data & PAGE_MASK, PAGE_SIZE);
 169         hose->cfg_data = mbase + (cfg_data & ~PAGE_MASK);
 170         hose->ops = &indirect_pci_ops;
 171         hose->indirect_type = flags;
 172 }