xref: /openbmc/linux/arch/mips/sgi-ip22/ip22-gio.c (revision f79e4d5f)
1 #include <linux/export.h>
2 #include <linux/kernel.h>
3 #include <linux/init.h>
4 #include <linux/slab.h>
5 
6 #include <asm/addrspace.h>
7 #include <asm/paccess.h>
8 #include <asm/gio_device.h>
9 #include <asm/sgi/gio.h>
10 #include <asm/sgi/hpc3.h>
11 #include <asm/sgi/mc.h>
12 #include <asm/sgi/ip22.h>
13 
14 static struct bus_type gio_bus_type;
15 
16 static struct {
17 	const char *name;
18 	__u8	   id;
19 } gio_name_table[] = {
20 	{ .name = "SGI Impact", .id = 0x10 },
21 	{ .name = "Phobos G160", .id = 0x35 },
22 	{ .name = "Phobos G130", .id = 0x36 },
23 	{ .name = "Phobos G100", .id = 0x37 },
24 	{ .name = "Set Engineering GFE", .id = 0x38 },
25 	/* fake IDs */
26 	{ .name = "SGI Newport", .id = 0x7e },
27 	{ .name = "SGI GR2/GR3", .id = 0x7f },
28 };
29 
30 static void gio_bus_release(struct device *dev)
31 {
32 	kfree(dev);
33 }
34 
35 static struct device gio_bus = {
36 	.init_name = "gio",
37 	.release = &gio_bus_release,
38 };
39 
40 /**
41  * gio_match_device - Tell if an of_device structure has a matching
42  * gio_match structure
43  * @ids: array of of device match structures to search in
44  * @dev: the of device structure to match against
45  *
46  * Used by a driver to check whether an of_device present in the
47  * system is in its list of supported devices.
48  */
49 const struct gio_device_id *gio_match_device(const struct gio_device_id *match,
50 		     const struct gio_device *dev)
51 {
52 	const struct gio_device_id *ids;
53 
54 	for (ids = match; ids->id != 0xff; ids++)
55 		if (ids->id == dev->id.id)
56 			return ids;
57 
58 	return NULL;
59 }
60 EXPORT_SYMBOL_GPL(gio_match_device);
61 
62 struct gio_device *gio_dev_get(struct gio_device *dev)
63 {
64 	struct device *tmp;
65 
66 	if (!dev)
67 		return NULL;
68 	tmp = get_device(&dev->dev);
69 	if (tmp)
70 		return to_gio_device(tmp);
71 	else
72 		return NULL;
73 }
74 EXPORT_SYMBOL_GPL(gio_dev_get);
75 
76 void gio_dev_put(struct gio_device *dev)
77 {
78 	if (dev)
79 		put_device(&dev->dev);
80 }
81 EXPORT_SYMBOL_GPL(gio_dev_put);
82 
83 /**
84  * gio_release_dev - free an gio device structure when all users of it are finished.
85  * @dev: device that's been disconnected
86  *
87  * Will be called only by the device core when all users of this gio device are
88  * done.
89  */
90 void gio_release_dev(struct device *dev)
91 {
92 	struct gio_device *giodev;
93 
94 	giodev = to_gio_device(dev);
95 	kfree(giodev);
96 }
97 EXPORT_SYMBOL_GPL(gio_release_dev);
98 
99 int gio_device_register(struct gio_device *giodev)
100 {
101 	giodev->dev.bus = &gio_bus_type;
102 	giodev->dev.parent = &gio_bus;
103 	return device_register(&giodev->dev);
104 }
105 EXPORT_SYMBOL_GPL(gio_device_register);
106 
107 void gio_device_unregister(struct gio_device *giodev)
108 {
109 	device_unregister(&giodev->dev);
110 }
111 EXPORT_SYMBOL_GPL(gio_device_unregister);
112 
113 static int gio_bus_match(struct device *dev, struct device_driver *drv)
114 {
115 	struct gio_device *gio_dev = to_gio_device(dev);
116 	struct gio_driver *gio_drv = to_gio_driver(drv);
117 
118 	return gio_match_device(gio_drv->id_table, gio_dev) != NULL;
119 }
120 
121 static int gio_device_probe(struct device *dev)
122 {
123 	int error = -ENODEV;
124 	struct gio_driver *drv;
125 	struct gio_device *gio_dev;
126 	const struct gio_device_id *match;
127 
128 	drv = to_gio_driver(dev->driver);
129 	gio_dev = to_gio_device(dev);
130 
131 	if (!drv->probe)
132 		return error;
133 
134 	gio_dev_get(gio_dev);
135 
136 	match = gio_match_device(drv->id_table, gio_dev);
137 	if (match)
138 		error = drv->probe(gio_dev, match);
139 	if (error)
140 		gio_dev_put(gio_dev);
141 
142 	return error;
143 }
144 
145 static int gio_device_remove(struct device *dev)
146 {
147 	struct gio_device *gio_dev = to_gio_device(dev);
148 	struct gio_driver *drv = to_gio_driver(dev->driver);
149 
150 	if (dev->driver && drv->remove)
151 		drv->remove(gio_dev);
152 	return 0;
153 }
154 
155 static 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 
164 static 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, "gio:%x\n", gio_dev->id.id);
169 
170 	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
171 }
172 static DEVICE_ATTR_RO(modalias);
173 
174 static 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, "%s", giodev->name);
181 }
182 static DEVICE_ATTR_RO(name);
183 
184 static 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, "%x", giodev->id.id);
191 }
192 static DEVICE_ATTR_RO(id);
193 
194 static struct attribute *gio_dev_attrs[] = {
195 	&dev_attr_modalias.attr,
196 	&dev_attr_name.attr,
197 	&dev_attr_id.attr,
198 	NULL,
199 };
200 ATTRIBUTE_GROUPS(gio_dev);
201 
202 static int gio_device_uevent(struct device *dev, struct kobj_uevent_env *env)
203 {
204 	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 
210 int 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 }
222 EXPORT_SYMBOL_GPL(gio_register_driver);
223 
224 void gio_unregister_driver(struct gio_driver *drv)
225 {
226 	driver_unregister(&drv->driver);
227 }
228 EXPORT_SYMBOL_GPL(gio_unregister_driver);
229 
230 void 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 }
247 EXPORT_SYMBOL_GPL(gio_set_master);
248 
249 void 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 
267 static 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 
312 static 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 
327 static 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, &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 + NEWPORT_USTATUS_OFFS, &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 		gio_dev->name = name;
367 		gio_dev->slotno = slotno;
368 		gio_dev->id.id = id;
369 		gio_dev->resource.start = addr;
370 		gio_dev->resource.end = addr + 0x3fffff;
371 		gio_dev->resource.flags = IORESOURCE_MEM;
372 		gio_dev->irq = irq;
373 		dev_set_name(&gio_dev->dev, "%d", slotno);
374 		gio_device_register(gio_dev);
375 	} else
376 		printk(KERN_INFO "GIO: slot %d : Empty\n", slotno);
377 }
378 
379 static struct bus_type gio_bus_type = {
380 	.name	   = "gio",
381 	.dev_groups = gio_dev_groups,
382 	.match	   = gio_bus_match,
383 	.probe	   = gio_device_probe,
384 	.remove	   = gio_device_remove,
385 	.shutdown  = gio_device_shutdown,
386 	.uevent	   = gio_device_uevent,
387 };
388 
389 static struct resource gio_bus_resource = {
390 	.start = GIO_SLOT_GFX_BASE,
391 	.end   = GIO_SLOT_GFX_BASE + 0x9fffff,
392 	.name  = "GIO Bus",
393 	.flags = IORESOURCE_MEM,
394 };
395 
396 int __init ip22_gio_init(void)
397 {
398 	unsigned int pbdma __maybe_unused;
399 	int ret;
400 
401 	ret = device_register(&gio_bus);
402 	if (ret) {
403 		put_device(&gio_bus);
404 		return ret;
405 	}
406 
407 	ret = bus_register(&gio_bus_type);
408 	if (!ret) {
409 		request_resource(&iomem_resource, &gio_bus_resource);
410 		printk(KERN_INFO "GIO: Probing bus...\n");
411 
412 		if (ip22_is_fullhouse()) {
413 			/* Indigo2 */
414 			ip22_check_gio(0, GIO_SLOT_GFX_BASE, SGI_GIO_1_IRQ);
415 			ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIO_1_IRQ);
416 		} else {
417 			/* Indy/Challenge S */
418 			if (get_dbe(pbdma, (unsigned int *)&hpc3c1->pbdma[1]))
419 				ip22_check_gio(0, GIO_SLOT_GFX_BASE,
420 					       SGI_GIO_0_IRQ);
421 			ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIOEXP0_IRQ);
422 			ip22_check_gio(2, GIO_SLOT_EXP1_BASE, SGI_GIOEXP1_IRQ);
423 		}
424 	} else
425 		device_unregister(&gio_bus);
426 
427 	return ret;
428 }
429 
430 subsys_initcall(ip22_gio_init);
431