1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/export.h>
3#include <linux/kernel.h>
4#include <linux/init.h>
5#include <linux/slab.h>
6
7#include <asm/addrspace.h>
8#include <asm/paccess.h>
9#include <asm/gio_device.h>
10#include <asm/sgi/gio.h>
11#include <asm/sgi/hpc3.h>
12#include <asm/sgi/mc.h>
13#include <asm/sgi/ip22.h>
14
15static const struct bus_type gio_bus_type;
16
17static struct {
18 const char *name;
19 __u8 id;
20} gio_name_table[] = {
21 { .name = "SGI Impact", .id = 0x10 },
22 { .name = "Phobos G160", .id = 0x35 },
23 { .name = "Phobos G130", .id = 0x36 },
24 { .name = "Phobos G100", .id = 0x37 },
25 { .name = "Set Engineering GFE", .id = 0x38 },
26 /* fake IDs */
27 { .name = "SGI Newport", .id = 0x7e },
28 { .name = "SGI GR2/GR3", .id = 0x7f },
29};
30
31static void gio_bus_release(struct device *dev)
32{
33 kfree(objp: dev);
34}
35
36static struct device gio_bus = {
37 .init_name = "gio",
38 .release = &gio_bus_release,
39};
40
41/**
42 * gio_match_device - Tell if an of_device structure has a matching
43 * gio_match structure
44 * @ids: array of of device match structures to search in
45 * @dev: the of device structure to match against
46 *
47 * Used by a driver to check whether an of_device present in the
48 * system is in its list of supported devices.
49 */
50static const struct gio_device_id *
51gio_match_device(const struct gio_device_id *match,
52 const struct gio_device *dev)
53{
54 const struct gio_device_id *ids;
55
56 for (ids = match; ids->id != 0xff; ids++)
57 if (ids->id == dev->id.id)
58 return ids;
59
60 return NULL;
61}
62
63struct gio_device *gio_dev_get(struct gio_device *dev)
64{
65 struct device *tmp;
66
67 if (!dev)
68 return NULL;
69 tmp = get_device(&dev->dev);
70 if (tmp)
71 return to_gio_device(tmp);
72 else
73 return NULL;
74}
75EXPORT_SYMBOL_GPL(gio_dev_get);
76
77void gio_dev_put(struct gio_device *dev)
78{
79 if (dev)
80 put_device(&dev->dev);
81}
82EXPORT_SYMBOL_GPL(gio_dev_put);
83
84/**
85 * gio_release_dev - free an gio device structure when all users of it are finished.
86 * @dev: device that's been disconnected
87 *
88 * Will be called only by the device core when all users of this gio device are
89 * done.
90 */
91void gio_release_dev(struct device *dev)
92{
93 struct gio_device *giodev;
94
95 giodev = to_gio_device(dev);
96 kfree(objp: giodev);
97}
98EXPORT_SYMBOL_GPL(gio_release_dev);
99
100int gio_device_register(struct gio_device *giodev)
101{
102 giodev->dev.bus = &gio_bus_type;
103 giodev->dev.parent = &gio_bus;
104 return device_register(&giodev->dev);
105}
106EXPORT_SYMBOL_GPL(gio_device_register);
107
108void gio_device_unregister(struct gio_device *giodev)
109{
110 device_unregister(&giodev->dev);
111}
112EXPORT_SYMBOL_GPL(gio_device_unregister);
113
114static int gio_bus_match(struct device *dev, struct device_driver *drv)
115{
116 struct gio_device *gio_dev = to_gio_device(dev);
117 struct gio_driver *gio_drv = to_gio_driver(drv);
118
119 return gio_match_device(match: gio_drv->id_table, dev: gio_dev) != NULL;
120}
121
122static int gio_device_probe(struct device *dev)
123{
124 int error = -ENODEV;
125 struct gio_driver *drv;
126 struct gio_device *gio_dev;
127 const struct gio_device_id *match;
128
129 drv = to_gio_driver(dev->driver);
130 gio_dev = to_gio_device(dev);
131
132 if (!drv->probe)
133 return error;
134
135 gio_dev_get(dev: gio_dev);
136
137 match = gio_match_device(match: drv->id_table, dev: gio_dev);
138 if (match)
139 error = drv->probe(gio_dev, match);
140 if (error)
141 gio_dev_put(dev: gio_dev);
142
143 return error;
144}
145
146static void gio_device_remove(struct device *dev)
147{
148 struct gio_device *gio_dev = to_gio_device(dev);
149 struct gio_driver *drv = to_gio_driver(dev->driver);
150
151 if (drv->remove)
152 drv->remove(gio_dev);
153}
154
155static void gio_device_shutdown(struct device *dev)
156{
157 struct gio_device *gio_dev = to_gio_device(dev);
158 struct gio_driver *drv = to_gio_driver(dev->driver);
159
160 if (dev->driver && drv->shutdown)
161 drv->shutdown(gio_dev);
162}
163
164static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
165 char *buf)
166{
167 struct gio_device *gio_dev = to_gio_device(dev);
168 int len = snprintf(buf, PAGE_SIZE, fmt: "gio:%x\n", gio_dev->id.id);
169
170 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
171}
172static DEVICE_ATTR_RO(modalias);
173
174static ssize_t name_show(struct device *dev,
175 struct device_attribute *attr, char *buf)
176{
177 struct gio_device *giodev;
178
179 giodev = to_gio_device(dev);
180 return sprintf(buf, fmt: "%s", giodev->name);
181}
182static DEVICE_ATTR_RO(name);
183
184static ssize_t id_show(struct device *dev,
185 struct device_attribute *attr, char *buf)
186{
187 struct gio_device *giodev;
188
189 giodev = to_gio_device(dev);
190 return sprintf(buf, fmt: "%x", giodev->id.id);
191}
192static DEVICE_ATTR_RO(id);
193
194static struct attribute *gio_dev_attrs[] = {
195 &dev_attr_modalias.attr,
196 &dev_attr_name.attr,
197 &dev_attr_id.attr,
198 NULL,
199};
200ATTRIBUTE_GROUPS(gio_dev);
201
202static int gio_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
203{
204 const struct gio_device *gio_dev = to_gio_device(dev);
205
206 add_uevent_var(env, "MODALIAS=gio:%x", gio_dev->id.id);
207 return 0;
208}
209
210int gio_register_driver(struct gio_driver *drv)
211{
212 /* initialize common driver fields */
213 if (!drv->driver.name)
214 drv->driver.name = drv->name;
215 if (!drv->driver.owner)
216 drv->driver.owner = drv->owner;
217 drv->driver.bus = &gio_bus_type;
218
219 /* register with core */
220 return driver_register(&drv->driver);
221}
222EXPORT_SYMBOL_GPL(gio_register_driver);
223
224void gio_unregister_driver(struct gio_driver *drv)
225{
226 driver_unregister(&drv->driver);
227}
228EXPORT_SYMBOL_GPL(gio_unregister_driver);
229
230void gio_set_master(struct gio_device *dev)
231{
232 u32 tmp = sgimc->giopar;
233
234 switch (dev->slotno) {
235 case 0:
236 tmp |= SGIMC_GIOPAR_MASTERGFX;
237 break;
238 case 1:
239 tmp |= SGIMC_GIOPAR_MASTEREXP0;
240 break;
241 case 2:
242 tmp |= SGIMC_GIOPAR_MASTEREXP1;
243 break;
244 }
245 sgimc->giopar = tmp;
246}
247EXPORT_SYMBOL_GPL(gio_set_master);
248
249void ip22_gio_set_64bit(int slotno)
250{
251 u32 tmp = sgimc->giopar;
252
253 switch (slotno) {
254 case 0:
255 tmp |= SGIMC_GIOPAR_GFX64;
256 break;
257 case 1:
258 tmp |= SGIMC_GIOPAR_EXP064;
259 break;
260 case 2:
261 tmp |= SGIMC_GIOPAR_EXP164;
262 break;
263 }
264 sgimc->giopar = tmp;
265}
266
267static int ip22_gio_id(unsigned long addr, u32 *res)
268{
269 u8 tmp8;
270 u8 tmp16;
271 u32 tmp32;
272 u8 *ptr8;
273 u16 *ptr16;
274 u32 *ptr32;
275
276 ptr32 = (void *)CKSEG1ADDR(addr);
277 if (!get_dbe(tmp32, ptr32)) {
278 /*
279 * We got no DBE, but this doesn't mean anything.
280 * If GIO is pipelined (which can't be disabled
281 * for GFX slot) we don't get a DBE, but we see
282 * the transfer size as data. So we do an 8bit
283 * and a 16bit access and check whether the common
284 * data matches
285 */
286 ptr8 = (void *)CKSEG1ADDR(addr + 3);
287 if (get_dbe(tmp8, ptr8)) {
288 /*
289 * 32bit access worked, but 8bit doesn't
290 * so we don't see phantom reads on
291 * a pipelined bus, but a real card which
292 * doesn't support 8 bit reads
293 */
294 *res = tmp32;
295 return 1;
296 }
297 ptr16 = (void *)CKSEG1ADDR(addr + 2);
298 get_dbe(tmp16, ptr16);
299 if (tmp8 == (tmp16 & 0xff) &&
300 tmp8 == (tmp32 & 0xff) &&
301 tmp16 == (tmp32 & 0xffff)) {
302 *res = tmp32;
303 return 1;
304 }
305 }
306 return 0; /* nothing here */
307}
308
309#define HQ2_MYSTERY_OFFS 0x6A07C
310#define NEWPORT_USTATUS_OFFS 0xF133C
311
312static int ip22_is_gr2(unsigned long addr)
313{
314 u32 tmp;
315 u32 *ptr;
316
317 /* HQ2 only allows 32bit accesses */
318 ptr = (void *)CKSEG1ADDR(addr + HQ2_MYSTERY_OFFS);
319 if (!get_dbe(tmp, ptr)) {
320 if (tmp == 0xdeadbeef)
321 return 1;
322 }
323 return 0;
324}
325
326
327static void ip22_check_gio(int slotno, unsigned long addr, int irq)
328{
329 const char *name = "Unknown";
330 struct gio_device *gio_dev;
331 u32 tmp;
332 __u8 id;
333 int i;
334
335 /* first look for GR2/GR3 by checking mystery register */
336 if (ip22_is_gr2(addr))
337 tmp = 0x7f;
338 else {
339 if (!ip22_gio_id(addr, res: &tmp)) {
340 /*
341 * no GIO signature at start address of slot
342 * since Newport doesn't have one, we check if
343 * user status register is readable
344 */
345 if (ip22_gio_id(addr: addr + NEWPORT_USTATUS_OFFS, res: &tmp))
346 tmp = 0x7e;
347 else
348 tmp = 0;
349 }
350 }
351 if (tmp) {
352 id = GIO_ID(tmp);
353 if (tmp & GIO_32BIT_ID) {
354 if (tmp & GIO_64BIT_IFACE)
355 ip22_gio_set_64bit(slotno);
356 }
357 for (i = 0; i < ARRAY_SIZE(gio_name_table); i++) {
358 if (id == gio_name_table[i].id) {
359 name = gio_name_table[i].name;
360 break;
361 }
362 }
363 printk(KERN_INFO "GIO: slot %d : %s (id %x)\n",
364 slotno, name, id);
365 gio_dev = kzalloc(sizeof *gio_dev, GFP_KERNEL);
366 if (!gio_dev)
367 return;
368 gio_dev->name = name;
369 gio_dev->slotno = slotno;
370 gio_dev->id.id = id;
371 gio_dev->resource.start = addr;
372 gio_dev->resource.end = addr + 0x3fffff;
373 gio_dev->resource.flags = IORESOURCE_MEM;
374 gio_dev->irq = irq;
375 dev_set_name(&gio_dev->dev, "%d", slotno);
376 gio_device_register(giodev: gio_dev);
377 } else
378 printk(KERN_INFO "GIO: slot %d : Empty\n", slotno);
379}
380
381static const struct bus_type gio_bus_type = {
382 .name = "gio",
383 .dev_groups = gio_dev_groups,
384 .match = gio_bus_match,
385 .probe = gio_device_probe,
386 .remove = gio_device_remove,
387 .shutdown = gio_device_shutdown,
388 .uevent = gio_device_uevent,
389};
390
391static struct resource gio_bus_resource = {
392 .start = GIO_SLOT_GFX_BASE,
393 .end = GIO_SLOT_GFX_BASE + 0x9fffff,
394 .name = "GIO Bus",
395 .flags = IORESOURCE_MEM,
396};
397
398int __init ip22_gio_init(void)
399{
400 unsigned int pbdma __maybe_unused;
401 int ret;
402
403 ret = device_register(&gio_bus);
404 if (ret) {
405 put_device(&gio_bus);
406 return ret;
407 }
408
409 ret = bus_register(&gio_bus_type);
410 if (!ret) {
411 request_resource(&iomem_resource, &gio_bus_resource);
412 printk(KERN_INFO "GIO: Probing bus...\n");
413
414 if (ip22_is_fullhouse()) {
415 /* Indigo2 */
416 ip22_check_gio(0, GIO_SLOT_GFX_BASE, SGI_GIO_1_IRQ);
417 ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIO_1_IRQ);
418 } else {
419 /* Indy/Challenge S */
420 if (get_dbe(pbdma, (unsigned int *)&hpc3c1->pbdma[1]))
421 ip22_check_gio(0, GIO_SLOT_GFX_BASE,
422 SGI_GIO_0_IRQ);
423 ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIOEXP0_IRQ);
424 ip22_check_gio(2, GIO_SLOT_EXP1_BASE, SGI_GIOEXP1_IRQ);
425 }
426 } else
427 device_unregister(&gio_bus);
428
429 return ret;
430}
431
432subsys_initcall(ip22_gio_init);
433

source code of linux/arch/mips/sgi-ip22/ip22-gio.c