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
nile4_pcibios_config_access(unsigned char access_type,struct pci_bus * bus,unsigned int devfn,int where,u32 * val)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
nile4_pcibios_read(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * val)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
nile4_pcibios_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)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 };
148