1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1999, 2000, 04, 06 Ralf Baechle (ralf@linux-mips.org)
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 */
9 #include <linux/pci.h>
10 #include <asm/paccess.h>
11 #include <asm/pci/bridge.h>
12 #include <asm/sn/arch.h>
13 #include <asm/sn/intr.h>
14 #include <asm/sn/sn0/hub.h>
15
16 /*
17 * Most of the IOC3 PCI config register aren't present
18 * we emulate what is needed for a normal PCI enumeration
19 */
emulate_ioc3_cfg(int where,int size)20 static u32 emulate_ioc3_cfg(int where, int size)
21 {
22 if (size == 1 && where == 0x3d)
23 return 0x01;
24 else if (size == 2 && where == 0x3c)
25 return 0x0100;
26 else if (size == 4 && where == 0x3c)
27 return 0x00000100;
28
29 return 0;
30 }
31
32 /*
33 * The Bridge ASIC supports both type 0 and type 1 access. Type 1 is
34 * not really documented, so right now I can't write code which uses it.
35 * Therefore we use type 0 accesses for now even though they won't work
36 * correctly for PCI-to-PCI bridges.
37 *
38 * The function is complicated by the ultimate brokenness of the IOC3 chip
39 * which is used in SGI systems. The IOC3 can only handle 32-bit PCI
40 * accesses and does only decode parts of it's address space.
41 */
42
pci_conf0_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)43 static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
44 int where, int size, u32 * value)
45 {
46 struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
47 bridge_t *bridge = bc->base;
48 int slot = PCI_SLOT(devfn);
49 int fn = PCI_FUNC(devfn);
50 volatile void *addr;
51 u32 cf, shift, mask;
52 int res;
53
54 addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
55 if (get_dbe(cf, (u32 *) addr))
56 return PCIBIOS_DEVICE_NOT_FOUND;
57
58 /*
59 * IOC3 is fucking fucked beyond belief ... Don't even give the
60 * generic PCI code a chance to look at it for real ...
61 */
62 if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
63 goto oh_my_gawd;
64
65 addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
66
67 if (size == 1)
68 res = get_dbe(*value, (u8 *) addr);
69 else if (size == 2)
70 res = get_dbe(*value, (u16 *) addr);
71 else
72 res = get_dbe(*value, (u32 *) addr);
73
74 return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
75
76 oh_my_gawd:
77
78 /*
79 * IOC3 is fucking fucked beyond belief ... Don't even give the
80 * generic PCI code a chance to look at the wrong register.
81 */
82 if ((where >= 0x14 && where < 0x40) || (where >= 0x48)) {
83 *value = emulate_ioc3_cfg(where, size);
84 return PCIBIOS_SUCCESSFUL;
85 }
86
87 /*
88 * IOC3 is fucking fucked beyond belief ... Don't try to access
89 * anything but 32-bit words ...
90 */
91 addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
92
93 if (get_dbe(cf, (u32 *) addr))
94 return PCIBIOS_DEVICE_NOT_FOUND;
95
96 shift = ((where & 3) << 3);
97 mask = (0xffffffffU >> ((4 - size) << 3));
98 *value = (cf >> shift) & mask;
99
100 return PCIBIOS_SUCCESSFUL;
101 }
102
pci_conf1_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)103 static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
104 int where, int size, u32 * value)
105 {
106 struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
107 bridge_t *bridge = bc->base;
108 int busno = bus->number;
109 int slot = PCI_SLOT(devfn);
110 int fn = PCI_FUNC(devfn);
111 volatile void *addr;
112 u32 cf, shift, mask;
113 int res;
114
115 bridge->b_pci_cfg = (busno << 16) | (slot << 11);
116 addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
117 if (get_dbe(cf, (u32 *) addr))
118 return PCIBIOS_DEVICE_NOT_FOUND;
119
120 /*
121 * IOC3 is fucking fucked beyond belief ... Don't even give the
122 * generic PCI code a chance to look at it for real ...
123 */
124 if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
125 goto oh_my_gawd;
126
127 bridge->b_pci_cfg = (busno << 16) | (slot << 11);
128 addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
129
130 if (size == 1)
131 res = get_dbe(*value, (u8 *) addr);
132 else if (size == 2)
133 res = get_dbe(*value, (u16 *) addr);
134 else
135 res = get_dbe(*value, (u32 *) addr);
136
137 return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
138
139 oh_my_gawd:
140
141 /*
142 * IOC3 is fucking fucked beyond belief ... Don't even give the
143 * generic PCI code a chance to look at the wrong register.
144 */
145 if ((where >= 0x14 && where < 0x40) || (where >= 0x48)) {
146 *value = emulate_ioc3_cfg(where, size);
147 return PCIBIOS_SUCCESSFUL;
148 }
149
150 /*
151 * IOC3 is fucking fucked beyond belief ... Don't try to access
152 * anything but 32-bit words ...
153 */
154 bridge->b_pci_cfg = (busno << 16) | (slot << 11);
155 addr = &bridge->b_type1_cfg.c[(fn << 8) | where];
156
157 if (get_dbe(cf, (u32 *) addr))
158 return PCIBIOS_DEVICE_NOT_FOUND;
159
160 shift = ((where & 3) << 3);
161 mask = (0xffffffffU >> ((4 - size) << 3));
162 *value = (cf >> shift) & mask;
163
164 return PCIBIOS_SUCCESSFUL;
165 }
166
pci_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)167 static int pci_read_config(struct pci_bus *bus, unsigned int devfn,
168 int where, int size, u32 * value)
169 {
170 if (!pci_is_root_bus(bus))
171 return pci_conf1_read_config(bus, devfn, where, size, value);
172
173 return pci_conf0_read_config(bus, devfn, where, size, value);
174 }
175
pci_conf0_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)176 static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
177 int where, int size, u32 value)
178 {
179 struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
180 bridge_t *bridge = bc->base;
181 int slot = PCI_SLOT(devfn);
182 int fn = PCI_FUNC(devfn);
183 volatile void *addr;
184 u32 cf, shift, mask, smask;
185 int res;
186
187 addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
188 if (get_dbe(cf, (u32 *) addr))
189 return PCIBIOS_DEVICE_NOT_FOUND;
190
191 /*
192 * IOC3 is fucking fucked beyond belief ... Don't even give the
193 * generic PCI code a chance to look at it for real ...
194 */
195 if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
196 goto oh_my_gawd;
197
198 addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
199
200 if (size == 1) {
201 res = put_dbe(value, (u8 *) addr);
202 } else if (size == 2) {
203 res = put_dbe(value, (u16 *) addr);
204 } else {
205 res = put_dbe(value, (u32 *) addr);
206 }
207
208 if (res)
209 return PCIBIOS_DEVICE_NOT_FOUND;
210
211 return PCIBIOS_SUCCESSFUL;
212
213 oh_my_gawd:
214
215 /*
216 * IOC3 is fucking fucked beyond belief ... Don't even give the
217 * generic PCI code a chance to touch the wrong register.
218 */
219 if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
220 return PCIBIOS_SUCCESSFUL;
221
222 /*
223 * IOC3 is fucking fucked beyond belief ... Don't try to access
224 * anything but 32-bit words ...
225 */
226 addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
227
228 if (get_dbe(cf, (u32 *) addr))
229 return PCIBIOS_DEVICE_NOT_FOUND;
230
231 shift = ((where & 3) << 3);
232 mask = (0xffffffffU >> ((4 - size) << 3));
233 smask = mask << shift;
234
235 cf = (cf & ~smask) | ((value & mask) << shift);
236 if (put_dbe(cf, (u32 *) addr))
237 return PCIBIOS_DEVICE_NOT_FOUND;
238
239 return PCIBIOS_SUCCESSFUL;
240 }
241
pci_conf1_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)242 static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
243 int where, int size, u32 value)
244 {
245 struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
246 bridge_t *bridge = bc->base;
247 int slot = PCI_SLOT(devfn);
248 int fn = PCI_FUNC(devfn);
249 int busno = bus->number;
250 volatile void *addr;
251 u32 cf, shift, mask, smask;
252 int res;
253
254 bridge->b_pci_cfg = (busno << 16) | (slot << 11);
255 addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
256 if (get_dbe(cf, (u32 *) addr))
257 return PCIBIOS_DEVICE_NOT_FOUND;
258
259 /*
260 * IOC3 is fucking fucked beyond belief ... Don't even give the
261 * generic PCI code a chance to look at it for real ...
262 */
263 if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
264 goto oh_my_gawd;
265
266 addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
267
268 if (size == 1) {
269 res = put_dbe(value, (u8 *) addr);
270 } else if (size == 2) {
271 res = put_dbe(value, (u16 *) addr);
272 } else {
273 res = put_dbe(value, (u32 *) addr);
274 }
275
276 if (res)
277 return PCIBIOS_DEVICE_NOT_FOUND;
278
279 return PCIBIOS_SUCCESSFUL;
280
281 oh_my_gawd:
282
283 /*
284 * IOC3 is fucking fucked beyond belief ... Don't even give the
285 * generic PCI code a chance to touch the wrong register.
286 */
287 if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
288 return PCIBIOS_SUCCESSFUL;
289
290 /*
291 * IOC3 is fucking fucked beyond belief ... Don't try to access
292 * anything but 32-bit words ...
293 */
294 addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
295
296 if (get_dbe(cf, (u32 *) addr))
297 return PCIBIOS_DEVICE_NOT_FOUND;
298
299 shift = ((where & 3) << 3);
300 mask = (0xffffffffU >> ((4 - size) << 3));
301 smask = mask << shift;
302
303 cf = (cf & ~smask) | ((value & mask) << shift);
304 if (put_dbe(cf, (u32 *) addr))
305 return PCIBIOS_DEVICE_NOT_FOUND;
306
307 return PCIBIOS_SUCCESSFUL;
308 }
309
pci_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)310 static int pci_write_config(struct pci_bus *bus, unsigned int devfn,
311 int where, int size, u32 value)
312 {
313 if (!pci_is_root_bus(bus))
314 return pci_conf1_write_config(bus, devfn, where, size, value);
315
316 return pci_conf0_write_config(bus, devfn, where, size, value);
317 }
318
319 struct pci_ops bridge_pci_ops = {
320 .read = pci_read_config,
321 .write = pci_write_config,
322 };
323
