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