arch/mips/pci/ops-nile4.c

   1 #include <linux/kernel.h>
   2 #include <linux/init.h>
   3 #include <linux/pci.h>
   4 #include <asm/bootinfo.h>
   5
   6 #include <asm/lasat/lasat.h>
   7 #include <asm/gt64120.h>
   8 #include <asm/nile4.h>
   9
  10 #define PCI_ACCESS_READ  0
  11 #define PCI_ACCESS_WRITE 1
  12
  13 #define LO(reg) (reg / 4)
  14 #define HI(reg) (reg / 4 + 1)
  15
  16 volatile unsigned long *const vrc_pciregs = (void *) Vrc5074_BASE;
  17
  18 static DEFINE_SPINLOCK(nile4_pci_lock);
  19
  20 static int nile4_pcibios_config_access(unsigned char access_type,
  21         struct pci_bus *bus, unsigned int devfn, int where, u32 *val)
  22 {
  23         unsigned char busnum = bus->number;
  24         u32 adr, mask, err;
  25
  26         if ((busnum == 0) && (PCI_SLOT(devfn) > 8))
  27                 /* The addressing scheme chosen leaves room for just
  28                  * 8 devices on the first busnum (besides the PCI
  29                  * controller itself) */
  30                 return PCIBIOS_DEVICE_NOT_FOUND;
  31
  32         if ((busnum == 0) && (devfn == PCI_DEVFN(0, 0))) {
  33                 /* Access controller registers directly */
  34                 if (access_type == PCI_ACCESS_WRITE) {
  35                         vrc_pciregs[(0x200 + where) >> 2] = *val;
  36                 } else {
  37                         *val = vrc_pciregs[(0x200 + where) >> 2];
  38                 }
  39                 return PCIBIOS_SUCCESSFUL;
  40         }
  41
  42         /* Temporarily map PCI Window 1 to config space */
  43         mask = vrc_pciregs[LO(NILE4_PCIINIT1)];
  44         vrc_pciregs[LO(NILE4_PCIINIT1)] = 0x0000001a | (busnum ? 0x200 : 0);
  45
  46         /* Clear PCI Error register. This also clears the Error Type
  47          * bits in the Control register */
  48         vrc_pciregs[LO(NILE4_PCIERR)] = 0;
  49         vrc_pciregs[HI(NILE4_PCIERR)] = 0;
  50
  51         /* Setup address */
  52         if (busnum == 0)
  53                 adr =
  54                     KSEG1ADDR(PCI_WINDOW1) +
  55                     ((1 << (PCI_SLOT(devfn) + 15)) | (PCI_FUNC(devfn) << 8)
  56                      | (where & ~3));
  57         else
  58                 adr = KSEG1ADDR(PCI_WINDOW1) | (busnum << 16) | (devfn << 8) |
  59                       (where & ~3);
  60
  61         if (access_type == PCI_ACCESS_WRITE)
  62                 *(u32 *) adr = *val;
  63         else
  64                 *val = *(u32 *) adr;
  65
  66         /* Check for master or target abort */
  67         err = (vrc_pciregs[HI(NILE4_PCICTRL)] >> 5) & 0x7;
  68
  69         /* Restore PCI Window 1 */
  70         vrc_pciregs[LO(NILE4_PCIINIT1)] = mask;
  71
  72         if (err)
  73                 return PCIBIOS_DEVICE_NOT_FOUND;
  74
  75         return PCIBIOS_SUCCESSFUL;
  76 }
  77
  78 static int nile4_pcibios_read(struct pci_bus *bus, unsigned int devfn,
  79         int where, int size, u32 *val)
  80 {
  81         unsigned long flags;
  82         u32 data = 0;
  83         int err;
  84
  85         if ((size == 2) && (where & 1))
  86                 return PCIBIOS_BAD_REGISTER_NUMBER;
  87         else if ((size == 4) && (where & 3))
  88                 return PCIBIOS_BAD_REGISTER_NUMBER;
  89
  90         spin_lock_irqsave(&nile4_pci_lock, flags);
  91         err = nile4_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
  92                                         &data);
  93         spin_unlock_irqrestore(&nile4_pci_lock, flags);
  94
  95         if (err)
  96                 return err;
  97
  98         if (size == 1)
  99                 *val = (data >> ((where & 3) << 3)) & 0xff;
 100         else if (size == 2)
 101                 *val = (data >> ((where & 3) << 3)) & 0xffff;
 102         else
 103                 *val = data;
 104
 105         return PCIBIOS_SUCCESSFUL;
 106 }
 107
 108 static int nile4_pcibios_write(struct pci_bus *bus, unsigned int devfn,
 109         int where, int size, u32 val)
 110 {
 111         unsigned long flags;
 112         u32 data = 0;
 113         int err;
 114
 115         if ((size == 2) && (where & 1))
 116                 return PCIBIOS_BAD_REGISTER_NUMBER;
 117         else if ((size == 4) && (where & 3))
 118                 return PCIBIOS_BAD_REGISTER_NUMBER;
 119
 120         spin_lock_irqsave(&nile4_pci_lock, flags);
 121         err = nile4_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
 122                                           &data);
 123         spin_unlock_irqrestore(&nile4_pci_lock, flags);
 124
 125         if (err)
 126                 return err;
 127
 128         if (size == 1)
 129                 data = (data & ~(0xff << ((where & 3) << 3))) |
 130                     (val << ((where & 3) << 3));
 131         else if (size == 2)
 132                 data = (data & ~(0xffff << ((where & 3) << 3))) |
 133                     (val << ((where & 3) << 3));
 134         else
 135                 data = val;
 136
 137         if (nile4_pcibios_config_access
 138             (PCI_ACCESS_WRITE, bus, devfn, where, &data))
 139                 return -1;
 140
 141         return PCIBIOS_SUCCESSFUL;
 142 }
 143
 144 struct pci_ops nile4_pci_ops = {
 145         .read = nile4_pcibios_read,
 146         .write = nile4_pcibios_write,
 147 };