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