1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ipmi_si_platform.c
4  *
5  * Handling for platform devices in IPMI (ACPI, OF, and things
6  * coming from the platform.
7  */
8 
9 #define pr_fmt(fmt) "ipmi_platform: " fmt
10 #define dev_fmt pr_fmt
11 
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/of_device.h>
15 #include <linux/of_platform.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/acpi.h>
19 #include "ipmi_si.h"
20 #include "ipmi_dmi.h"
21 
22 static bool platform_registered;
23 static bool si_tryplatform = true;
24 #ifdef CONFIG_ACPI
25 static bool          si_tryacpi = true;
26 #endif
27 #ifdef CONFIG_OF
28 static bool          si_tryopenfirmware = true;
29 #endif
30 #ifdef CONFIG_DMI
31 static bool          si_trydmi = true;
32 #else
33 static bool          si_trydmi = false;
34 #endif
35 
36 module_param_named(tryplatform, si_tryplatform, bool, 0);
37 MODULE_PARM_DESC(tryplatform, "Setting this to zero will disable the"
38 		 " default scan of the interfaces identified via platform"
39 		 " interfaces besides ACPI, OpenFirmware, and DMI");
40 #ifdef CONFIG_ACPI
41 module_param_named(tryacpi, si_tryacpi, bool, 0);
42 MODULE_PARM_DESC(tryacpi, "Setting this to zero will disable the"
43 		 " default scan of the interfaces identified via ACPI");
44 #endif
45 #ifdef CONFIG_OF
46 module_param_named(tryopenfirmware, si_tryopenfirmware, bool, 0);
47 MODULE_PARM_DESC(tryopenfirmware, "Setting this to zero will disable the"
48 		 " default scan of the interfaces identified via OpenFirmware");
49 #endif
50 #ifdef CONFIG_DMI
51 module_param_named(trydmi, si_trydmi, bool, 0);
52 MODULE_PARM_DESC(trydmi, "Setting this to zero will disable the"
53 		 " default scan of the interfaces identified via DMI");
54 #endif
55 
56 #ifdef CONFIG_ACPI
57 /* For GPE-type interrupts. */
58 static u32 ipmi_acpi_gpe(acpi_handle gpe_device,
59 	u32 gpe_number, void *context)
60 {
61 	struct si_sm_io *io = context;
62 
63 	ipmi_si_irq_handler(io->irq, io->irq_handler_data);
64 	return ACPI_INTERRUPT_HANDLED;
65 }
66 
67 static void acpi_gpe_irq_cleanup(struct si_sm_io *io)
68 {
69 	if (!io->irq)
70 		return;
71 
72 	ipmi_irq_start_cleanup(io);
73 	acpi_remove_gpe_handler(NULL, io->irq, &ipmi_acpi_gpe);
74 }
75 
76 static int acpi_gpe_irq_setup(struct si_sm_io *io)
77 {
78 	acpi_status status;
79 
80 	if (!io->irq)
81 		return 0;
82 
83 	status = acpi_install_gpe_handler(NULL,
84 					  io->irq,
85 					  ACPI_GPE_LEVEL_TRIGGERED,
86 					  &ipmi_acpi_gpe,
87 					  io);
88 	if (status != AE_OK) {
89 		dev_warn(io->dev,
90 			 "Unable to claim ACPI GPE %d, running polled\n",
91 			 io->irq);
92 		io->irq = 0;
93 		return -EINVAL;
94 	} else {
95 		io->irq_cleanup = acpi_gpe_irq_cleanup;
96 		ipmi_irq_finish_setup(io);
97 		dev_info(io->dev, "Using ACPI GPE %d\n", io->irq);
98 		return 0;
99 	}
100 }
101 #endif
102 
103 static struct resource *
104 ipmi_get_info_from_resources(struct platform_device *pdev,
105 			     struct si_sm_io *io)
106 {
107 	struct resource *res, *res_second;
108 
109 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
110 	if (res) {
111 		io->addr_space = IPMI_IO_ADDR_SPACE;
112 	} else {
113 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
114 		if (res)
115 			io->addr_space = IPMI_MEM_ADDR_SPACE;
116 	}
117 	if (!res) {
118 		dev_err(&pdev->dev, "no I/O or memory address\n");
119 		return NULL;
120 	}
121 	io->addr_data = res->start;
122 
123 	io->regspacing = DEFAULT_REGSPACING;
124 	res_second = platform_get_resource(pdev,
125 			       (io->addr_space == IPMI_IO_ADDR_SPACE) ?
126 					IORESOURCE_IO : IORESOURCE_MEM,
127 			       1);
128 	if (res_second) {
129 		if (res_second->start > io->addr_data)
130 			io->regspacing = res_second->start - io->addr_data;
131 	}
132 
133 	return res;
134 }
135 
136 static int platform_ipmi_probe(struct platform_device *pdev)
137 {
138 	struct si_sm_io io;
139 	u8 type, slave_addr, addr_source, regsize, regshift;
140 	int rv;
141 
142 	rv = device_property_read_u8(&pdev->dev, "addr-source", &addr_source);
143 	if (rv)
144 		addr_source = SI_PLATFORM;
145 	if (addr_source >= SI_LAST)
146 		return -EINVAL;
147 
148 	if (addr_source == SI_SMBIOS) {
149 		if (!si_trydmi)
150 			return -ENODEV;
151 	} else if (addr_source != SI_HARDCODED) {
152 		if (!si_tryplatform)
153 			return -ENODEV;
154 	}
155 
156 	rv = device_property_read_u8(&pdev->dev, "ipmi-type", &type);
157 	if (rv)
158 		return -ENODEV;
159 
160 	memset(&io, 0, sizeof(io));
161 	io.addr_source = addr_source;
162 	dev_info(&pdev->dev, "probing via %s\n",
163 		 ipmi_addr_src_to_str(addr_source));
164 
165 	switch (type) {
166 	case SI_KCS:
167 	case SI_SMIC:
168 	case SI_BT:
169 		io.si_type = type;
170 		break;
171 	case SI_TYPE_INVALID: /* User disabled this in hardcode. */
172 		return -ENODEV;
173 	default:
174 		dev_err(&pdev->dev, "ipmi-type property is invalid\n");
175 		return -EINVAL;
176 	}
177 
178 	io.regsize = DEFAULT_REGSIZE;
179 	rv = device_property_read_u8(&pdev->dev, "reg-size", &regsize);
180 	if (!rv)
181 		io.regsize = regsize;
182 
183 	io.regshift = 0;
184 	rv = device_property_read_u8(&pdev->dev, "reg-shift", &regshift);
185 	if (!rv)
186 		io.regshift = regshift;
187 
188 	if (!ipmi_get_info_from_resources(pdev, &io))
189 		return -EINVAL;
190 
191 	rv = device_property_read_u8(&pdev->dev, "slave-addr", &slave_addr);
192 	if (rv)
193 		io.slave_addr = 0x20;
194 	else
195 		io.slave_addr = slave_addr;
196 
197 	io.irq = platform_get_irq_optional(pdev, 0);
198 	if (io.irq > 0)
199 		io.irq_setup = ipmi_std_irq_setup;
200 	else
201 		io.irq = 0;
202 
203 	io.dev = &pdev->dev;
204 
205 	pr_info("ipmi_si: %s: %s %#lx regsize %d spacing %d irq %d\n",
206 		ipmi_addr_src_to_str(addr_source),
207 		(io.addr_space == IPMI_IO_ADDR_SPACE) ? "io" : "mem",
208 		io.addr_data, io.regsize, io.regspacing, io.irq);
209 
210 	ipmi_si_add_smi(&io);
211 
212 	return 0;
213 }
214 
215 #ifdef CONFIG_OF
216 static const struct of_device_id of_ipmi_match[] = {
217 	{ .type = "ipmi", .compatible = "ipmi-kcs",
218 	  .data = (void *)(unsigned long) SI_KCS },
219 	{ .type = "ipmi", .compatible = "ipmi-smic",
220 	  .data = (void *)(unsigned long) SI_SMIC },
221 	{ .type = "ipmi", .compatible = "ipmi-bt",
222 	  .data = (void *)(unsigned long) SI_BT },
223 	{},
224 };
225 MODULE_DEVICE_TABLE(of, of_ipmi_match);
226 
227 static int of_ipmi_probe(struct platform_device *pdev)
228 {
229 	const struct of_device_id *match;
230 	struct si_sm_io io;
231 	struct resource resource;
232 	const __be32 *regsize, *regspacing, *regshift;
233 	struct device_node *np = pdev->dev.of_node;
234 	int ret;
235 	int proplen;
236 
237 	if (!si_tryopenfirmware)
238 		return -ENODEV;
239 
240 	dev_info(&pdev->dev, "probing via device tree\n");
241 
242 	match = of_match_device(of_ipmi_match, &pdev->dev);
243 	if (!match)
244 		return -ENODEV;
245 
246 	if (!of_device_is_available(np))
247 		return -EINVAL;
248 
249 	ret = of_address_to_resource(np, 0, &resource);
250 	if (ret) {
251 		dev_warn(&pdev->dev, "invalid address from OF\n");
252 		return ret;
253 	}
254 
255 	regsize = of_get_property(np, "reg-size", &proplen);
256 	if (regsize && proplen != 4) {
257 		dev_warn(&pdev->dev, "invalid regsize from OF\n");
258 		return -EINVAL;
259 	}
260 
261 	regspacing = of_get_property(np, "reg-spacing", &proplen);
262 	if (regspacing && proplen != 4) {
263 		dev_warn(&pdev->dev, "invalid regspacing from OF\n");
264 		return -EINVAL;
265 	}
266 
267 	regshift = of_get_property(np, "reg-shift", &proplen);
268 	if (regshift && proplen != 4) {
269 		dev_warn(&pdev->dev, "invalid regshift from OF\n");
270 		return -EINVAL;
271 	}
272 
273 	memset(&io, 0, sizeof(io));
274 	io.si_type	= (enum si_type) match->data;
275 	io.addr_source	= SI_DEVICETREE;
276 	io.irq_setup	= ipmi_std_irq_setup;
277 
278 	if (resource.flags & IORESOURCE_IO)
279 		io.addr_space = IPMI_IO_ADDR_SPACE;
280 	else
281 		io.addr_space = IPMI_MEM_ADDR_SPACE;
282 
283 	io.addr_data	= resource.start;
284 
285 	io.regsize	= regsize ? be32_to_cpup(regsize) : DEFAULT_REGSIZE;
286 	io.regspacing	= regspacing ? be32_to_cpup(regspacing) : DEFAULT_REGSPACING;
287 	io.regshift	= regshift ? be32_to_cpup(regshift) : 0;
288 
289 	io.irq		= irq_of_parse_and_map(pdev->dev.of_node, 0);
290 	io.dev		= &pdev->dev;
291 
292 	dev_dbg(&pdev->dev, "addr 0x%lx regsize %d spacing %d irq %d\n",
293 		io.addr_data, io.regsize, io.regspacing, io.irq);
294 
295 	return ipmi_si_add_smi(&io);
296 }
297 #else
298 #define of_ipmi_match NULL
299 static int of_ipmi_probe(struct platform_device *dev)
300 {
301 	return -ENODEV;
302 }
303 #endif
304 
305 #ifdef CONFIG_ACPI
306 static int find_slave_address(struct si_sm_io *io, int slave_addr)
307 {
308 #ifdef CONFIG_IPMI_DMI_DECODE
309 	if (!slave_addr)
310 		slave_addr = ipmi_dmi_get_slave_addr(io->si_type,
311 						     io->addr_space,
312 						     io->addr_data);
313 #endif
314 
315 	return slave_addr;
316 }
317 
318 static int acpi_ipmi_probe(struct platform_device *pdev)
319 {
320 	struct si_sm_io io;
321 	acpi_handle handle;
322 	acpi_status status;
323 	unsigned long long tmp;
324 	struct resource *res;
325 	int rv = -EINVAL;
326 
327 	if (!si_tryacpi)
328 		return -ENODEV;
329 
330 	handle = ACPI_HANDLE(&pdev->dev);
331 	if (!handle)
332 		return -ENODEV;
333 
334 	memset(&io, 0, sizeof(io));
335 	io.addr_source = SI_ACPI;
336 	dev_info(&pdev->dev, "probing via ACPI\n");
337 
338 	io.addr_info.acpi_info.acpi_handle = handle;
339 
340 	/* _IFT tells us the interface type: KCS, BT, etc */
341 	status = acpi_evaluate_integer(handle, "_IFT", NULL, &tmp);
342 	if (ACPI_FAILURE(status)) {
343 		dev_err(&pdev->dev,
344 			"Could not find ACPI IPMI interface type\n");
345 		goto err_free;
346 	}
347 
348 	switch (tmp) {
349 	case 1:
350 		io.si_type = SI_KCS;
351 		break;
352 	case 2:
353 		io.si_type = SI_SMIC;
354 		break;
355 	case 3:
356 		io.si_type = SI_BT;
357 		break;
358 	case 4: /* SSIF, just ignore */
359 		rv = -ENODEV;
360 		goto err_free;
361 	default:
362 		dev_info(&pdev->dev, "unknown IPMI type %lld\n", tmp);
363 		goto err_free;
364 	}
365 
366 	io.regsize = DEFAULT_REGSIZE;
367 	io.regshift = 0;
368 
369 	res = ipmi_get_info_from_resources(pdev, &io);
370 	if (!res) {
371 		rv = -EINVAL;
372 		goto err_free;
373 	}
374 
375 	/* If _GPE exists, use it; otherwise use standard interrupts */
376 	status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
377 	if (ACPI_SUCCESS(status)) {
378 		io.irq = tmp;
379 		io.irq_setup = acpi_gpe_irq_setup;
380 	} else {
381 		int irq = platform_get_irq_optional(pdev, 0);
382 
383 		if (irq > 0) {
384 			io.irq = irq;
385 			io.irq_setup = ipmi_std_irq_setup;
386 		}
387 	}
388 
389 	io.slave_addr = find_slave_address(&io, io.slave_addr);
390 
391 	io.dev = &pdev->dev;
392 
393 	dev_info(io.dev, "%pR regsize %d spacing %d irq %d\n",
394 		 res, io.regsize, io.regspacing, io.irq);
395 
396 	return ipmi_si_add_smi(&io);
397 
398 err_free:
399 	return rv;
400 }
401 
402 static const struct acpi_device_id acpi_ipmi_match[] = {
403 	{ "IPI0001", 0 },
404 	{ },
405 };
406 MODULE_DEVICE_TABLE(acpi, acpi_ipmi_match);
407 #else
408 static int acpi_ipmi_probe(struct platform_device *dev)
409 {
410 	return -ENODEV;
411 }
412 #endif
413 
414 static int ipmi_probe(struct platform_device *pdev)
415 {
416 	if (pdev->dev.of_node && of_ipmi_probe(pdev) == 0)
417 		return 0;
418 
419 	if (acpi_ipmi_probe(pdev) == 0)
420 		return 0;
421 
422 	return platform_ipmi_probe(pdev);
423 }
424 
425 static int ipmi_remove(struct platform_device *pdev)
426 {
427 	return ipmi_si_remove_by_dev(&pdev->dev);
428 }
429 
430 static int pdev_match_name(struct device *dev, const void *data)
431 {
432 	struct platform_device *pdev = to_platform_device(dev);
433 	const char *name = data;
434 
435 	return strcmp(pdev->name, name) == 0;
436 }
437 
438 void ipmi_remove_platform_device_by_name(char *name)
439 {
440 	struct device *dev;
441 
442 	while ((dev = bus_find_device(&platform_bus_type, NULL, name,
443 				      pdev_match_name))) {
444 		struct platform_device *pdev = to_platform_device(dev);
445 
446 		platform_device_unregister(pdev);
447 		put_device(dev);
448 	}
449 }
450 
451 static const struct platform_device_id si_plat_ids[] = {
452 	{ "dmi-ipmi-si", 0 },
453 	{ "hardcode-ipmi-si", 0 },
454 	{ "hotmod-ipmi-si", 0 },
455 	{ }
456 };
457 
458 struct platform_driver ipmi_platform_driver = {
459 	.driver = {
460 		.name = SI_DEVICE_NAME,
461 		.of_match_table = of_ipmi_match,
462 		.acpi_match_table = ACPI_PTR(acpi_ipmi_match),
463 	},
464 	.probe		= ipmi_probe,
465 	.remove		= ipmi_remove,
466 	.id_table       = si_plat_ids
467 };
468 
469 void ipmi_si_platform_init(void)
470 {
471 	int rv = platform_driver_register(&ipmi_platform_driver);
472 	if (rv)
473 		pr_err("Unable to register driver: %d\n", rv);
474 	else
475 		platform_registered = true;
476 }
477 
478 void ipmi_si_platform_shutdown(void)
479 {
480 	if (platform_registered)
481 		platform_driver_unregister(&ipmi_platform_driver);
482 }
483