xref: /openbmc/linux/arch/mips/sgi-ip22/ip22-gio.c (revision 4f6cce39)
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 
173 static ssize_t name_show(struct device *dev,
174 			 struct device_attribute *attr, char *buf)
175 {
176 	struct gio_device *giodev;
177 
178 	giodev = to_gio_device(dev);
179 	return sprintf(buf, "%s", giodev->name);
180 }
181 
182 static ssize_t id_show(struct device *dev,
183 		       struct device_attribute *attr, char *buf)
184 {
185 	struct gio_device *giodev;
186 
187 	giodev = to_gio_device(dev);
188 	return sprintf(buf, "%x", giodev->id.id);
189 }
190 
191 static struct device_attribute gio_dev_attrs[] = {
192 	__ATTR_RO(modalias),
193 	__ATTR_RO(name),
194 	__ATTR_RO(id),
195 	__ATTR_NULL,
196 };
197 
198 static int gio_device_uevent(struct device *dev, struct kobj_uevent_env *env)
199 {
200 	struct gio_device *gio_dev = to_gio_device(dev);
201 
202 	add_uevent_var(env, "MODALIAS=gio:%x", gio_dev->id.id);
203 	return 0;
204 }
205 
206 int gio_register_driver(struct gio_driver *drv)
207 {
208 	/* initialize common driver fields */
209 	if (!drv->driver.name)
210 		drv->driver.name = drv->name;
211 	if (!drv->driver.owner)
212 		drv->driver.owner = drv->owner;
213 	drv->driver.bus = &gio_bus_type;
214 
215 	/* register with core */
216 	return driver_register(&drv->driver);
217 }
218 EXPORT_SYMBOL_GPL(gio_register_driver);
219 
220 void gio_unregister_driver(struct gio_driver *drv)
221 {
222 	driver_unregister(&drv->driver);
223 }
224 EXPORT_SYMBOL_GPL(gio_unregister_driver);
225 
226 void gio_set_master(struct gio_device *dev)
227 {
228 	u32 tmp = sgimc->giopar;
229 
230 	switch (dev->slotno) {
231 	case 0:
232 		tmp |= SGIMC_GIOPAR_MASTERGFX;
233 		break;
234 	case 1:
235 		tmp |= SGIMC_GIOPAR_MASTEREXP0;
236 		break;
237 	case 2:
238 		tmp |= SGIMC_GIOPAR_MASTEREXP1;
239 		break;
240 	}
241 	sgimc->giopar = tmp;
242 }
243 EXPORT_SYMBOL_GPL(gio_set_master);
244 
245 void ip22_gio_set_64bit(int slotno)
246 {
247 	u32 tmp = sgimc->giopar;
248 
249 	switch (slotno) {
250 	case 0:
251 		tmp |= SGIMC_GIOPAR_GFX64;
252 		break;
253 	case 1:
254 		tmp |= SGIMC_GIOPAR_EXP064;
255 		break;
256 	case 2:
257 		tmp |= SGIMC_GIOPAR_EXP164;
258 		break;
259 	}
260 	sgimc->giopar = tmp;
261 }
262 
263 static int ip22_gio_id(unsigned long addr, u32 *res)
264 {
265 	u8 tmp8;
266 	u8 tmp16;
267 	u32 tmp32;
268 	u8 *ptr8;
269 	u16 *ptr16;
270 	u32 *ptr32;
271 
272 	ptr32 = (void *)CKSEG1ADDR(addr);
273 	if (!get_dbe(tmp32, ptr32)) {
274 		/*
275 		 * We got no DBE, but this doesn't mean anything.
276 		 * If GIO is pipelined (which can't be disabled
277 		 * for GFX slot) we don't get a DBE, but we see
278 		 * the transfer size as data. So we do an 8bit
279 		 * and a 16bit access and check whether the common
280 		 * data matches
281 		 */
282 		ptr8 = (void *)CKSEG1ADDR(addr + 3);
283 		if (get_dbe(tmp8, ptr8)) {
284 			/*
285 			 * 32bit access worked, but 8bit doesn't
286 			 * so we don't see phantom reads on
287 			 * a pipelined bus, but a real card which
288 			 * doesn't support 8 bit reads
289 			 */
290 			*res = tmp32;
291 			return 1;
292 		}
293 		ptr16 = (void *)CKSEG1ADDR(addr + 2);
294 		get_dbe(tmp16, ptr16);
295 		if (tmp8 == (tmp16 & 0xff) &&
296 		    tmp8 == (tmp32 & 0xff) &&
297 		    tmp16 == (tmp32 & 0xffff)) {
298 			*res = tmp32;
299 			return 1;
300 		}
301 	}
302 	return 0; /* nothing here */
303 }
304 
305 #define HQ2_MYSTERY_OFFS       0x6A07C
306 #define NEWPORT_USTATUS_OFFS   0xF133C
307 
308 static int ip22_is_gr2(unsigned long addr)
309 {
310 	u32 tmp;
311 	u32 *ptr;
312 
313 	/* HQ2 only allows 32bit accesses */
314 	ptr = (void *)CKSEG1ADDR(addr + HQ2_MYSTERY_OFFS);
315 	if (!get_dbe(tmp, ptr)) {
316 		if (tmp == 0xdeadbeef)
317 			return 1;
318 	}
319 	return 0;
320 }
321 
322 
323 static void ip22_check_gio(int slotno, unsigned long addr, int irq)
324 {
325 	const char *name = "Unknown";
326 	struct gio_device *gio_dev;
327 	u32 tmp;
328 	__u8 id;
329 	int i;
330 
331 	/* first look for GR2/GR3 by checking mystery register */
332 	if (ip22_is_gr2(addr))
333 		tmp = 0x7f;
334 	else {
335 		if (!ip22_gio_id(addr, &tmp)) {
336 			/*
337 			 * no GIO signature at start address of slot
338 			 * since Newport doesn't have one, we check if
339 			 * user status register is readable
340 			 */
341 			if (ip22_gio_id(addr + NEWPORT_USTATUS_OFFS, &tmp))
342 				tmp = 0x7e;
343 			else
344 				tmp = 0;
345 		}
346 	}
347 	if (tmp) {
348 		id = GIO_ID(tmp);
349 		if (tmp & GIO_32BIT_ID) {
350 			if (tmp & GIO_64BIT_IFACE)
351 				ip22_gio_set_64bit(slotno);
352 		}
353 		for (i = 0; i < ARRAY_SIZE(gio_name_table); i++) {
354 			if (id == gio_name_table[i].id) {
355 				name = gio_name_table[i].name;
356 				break;
357 			}
358 		}
359 		printk(KERN_INFO "GIO: slot %d : %s (id %x)\n",
360 		       slotno, name, id);
361 		gio_dev = kzalloc(sizeof *gio_dev, GFP_KERNEL);
362 		gio_dev->name = name;
363 		gio_dev->slotno = slotno;
364 		gio_dev->id.id = id;
365 		gio_dev->resource.start = addr;
366 		gio_dev->resource.end = addr + 0x3fffff;
367 		gio_dev->resource.flags = IORESOURCE_MEM;
368 		gio_dev->irq = irq;
369 		dev_set_name(&gio_dev->dev, "%d", slotno);
370 		gio_device_register(gio_dev);
371 	} else
372 		printk(KERN_INFO "GIO: slot %d : Empty\n", slotno);
373 }
374 
375 static struct bus_type gio_bus_type = {
376 	.name	   = "gio",
377 	.dev_attrs = gio_dev_attrs,
378 	.match	   = gio_bus_match,
379 	.probe	   = gio_device_probe,
380 	.remove	   = gio_device_remove,
381 	.shutdown  = gio_device_shutdown,
382 	.uevent	   = gio_device_uevent,
383 };
384 
385 static struct resource gio_bus_resource = {
386 	.start = GIO_SLOT_GFX_BASE,
387 	.end   = GIO_SLOT_GFX_BASE + 0x9fffff,
388 	.name  = "GIO Bus",
389 	.flags = IORESOURCE_MEM,
390 };
391 
392 int __init ip22_gio_init(void)
393 {
394 	unsigned int pbdma __maybe_unused;
395 	int ret;
396 
397 	ret = device_register(&gio_bus);
398 	if (ret) {
399 		put_device(&gio_bus);
400 		return ret;
401 	}
402 
403 	ret = bus_register(&gio_bus_type);
404 	if (!ret) {
405 		request_resource(&iomem_resource, &gio_bus_resource);
406 		printk(KERN_INFO "GIO: Probing bus...\n");
407 
408 		if (ip22_is_fullhouse()) {
409 			/* Indigo2 */
410 			ip22_check_gio(0, GIO_SLOT_GFX_BASE, SGI_GIO_1_IRQ);
411 			ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIO_1_IRQ);
412 		} else {
413 			/* Indy/Challenge S */
414 			if (get_dbe(pbdma, (unsigned int *)&hpc3c1->pbdma[1]))
415 				ip22_check_gio(0, GIO_SLOT_GFX_BASE,
416 					       SGI_GIO_0_IRQ);
417 			ip22_check_gio(1, GIO_SLOT_EXP0_BASE, SGI_GIOEXP0_IRQ);
418 			ip22_check_gio(2, GIO_SLOT_EXP1_BASE, SGI_GIOEXP1_IRQ);
419 		}
420 	} else
421 		device_unregister(&gio_bus);
422 
423 	return ret;
424 }
425 
426 subsys_initcall(ip22_gio_init);
427