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09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
74c5b31c MW |
2 | /* |
3 | * Copyright 2010 Google Inc. All Rights Reserved. | |
4 | * Author: dlaurie@google.com (Duncan Laurie) | |
5 | * | |
6 | * Re-worked to expose sysfs APIs by mikew@google.com (Mike Waychison) | |
7 | * | |
8 | * EFI SMI interface for Google platforms | |
9 | */ | |
10 | ||
11 | #include <linux/kernel.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/types.h> | |
14 | #include <linux/device.h> | |
15 | #include <linux/platform_device.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/string.h> | |
18 | #include <linux/spinlock.h> | |
19 | #include <linux/dma-mapping.h> | |
20 | #include <linux/dmapool.h> | |
21 | #include <linux/fs.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/ioctl.h> | |
24 | #include <linux/acpi.h> | |
25 | #include <linux/io.h> | |
26 | #include <linux/uaccess.h> | |
27 | #include <linux/dmi.h> | |
28 | #include <linux/kdebug.h> | |
29 | #include <linux/reboot.h> | |
30 | #include <linux/efi.h> | |
afd605f6 | 31 | #include <linux/module.h> |
a614e192 | 32 | #include <linux/ucs2_string.h> |
8942b2d5 | 33 | #include <linux/suspend.h> |
74c5b31c MW |
34 | |
35 | #define GSMI_SHUTDOWN_CLEAN 0 /* Clean Shutdown */ | |
36 | /* TODO(mikew@google.com): Tie in HARDLOCKUP_DETECTOR with NMIWDT */ | |
37 | #define GSMI_SHUTDOWN_NMIWDT 1 /* NMI Watchdog */ | |
38 | #define GSMI_SHUTDOWN_PANIC 2 /* Panic */ | |
39 | #define GSMI_SHUTDOWN_OOPS 3 /* Oops */ | |
40 | #define GSMI_SHUTDOWN_DIE 4 /* Die -- No longer meaningful */ | |
41 | #define GSMI_SHUTDOWN_MCE 5 /* Machine Check */ | |
42 | #define GSMI_SHUTDOWN_SOFTWDT 6 /* Software Watchdog */ | |
43 | #define GSMI_SHUTDOWN_MBE 7 /* Uncorrected ECC */ | |
44 | #define GSMI_SHUTDOWN_TRIPLE 8 /* Triple Fault */ | |
45 | ||
46 | #define DRIVER_VERSION "1.0" | |
47 | #define GSMI_GUID_SIZE 16 | |
48 | #define GSMI_BUF_SIZE 1024 | |
49 | #define GSMI_BUF_ALIGN sizeof(u64) | |
50 | #define GSMI_CALLBACK 0xef | |
51 | ||
52 | /* SMI return codes */ | |
53 | #define GSMI_SUCCESS 0x00 | |
54 | #define GSMI_UNSUPPORTED2 0x03 | |
55 | #define GSMI_LOG_FULL 0x0b | |
56 | #define GSMI_VAR_NOT_FOUND 0x0e | |
57 | #define GSMI_HANDSHAKE_SPIN 0x7d | |
58 | #define GSMI_HANDSHAKE_CF 0x7e | |
59 | #define GSMI_HANDSHAKE_NONE 0x7f | |
60 | #define GSMI_INVALID_PARAMETER 0x82 | |
61 | #define GSMI_UNSUPPORTED 0x83 | |
62 | #define GSMI_BUFFER_TOO_SMALL 0x85 | |
63 | #define GSMI_NOT_READY 0x86 | |
64 | #define GSMI_DEVICE_ERROR 0x87 | |
65 | #define GSMI_NOT_FOUND 0x8e | |
66 | ||
67 | #define QUIRKY_BOARD_HASH 0x78a30a50 | |
68 | ||
69 | /* Internally used commands passed to the firmware */ | |
70 | #define GSMI_CMD_GET_NVRAM_VAR 0x01 | |
71 | #define GSMI_CMD_GET_NEXT_VAR 0x02 | |
72 | #define GSMI_CMD_SET_NVRAM_VAR 0x03 | |
73 | #define GSMI_CMD_SET_EVENT_LOG 0x08 | |
74 | #define GSMI_CMD_CLEAR_EVENT_LOG 0x09 | |
8942b2d5 FS |
75 | #define GSMI_CMD_LOG_S0IX_SUSPEND 0x0a |
76 | #define GSMI_CMD_LOG_S0IX_RESUME 0x0b | |
74c5b31c MW |
77 | #define GSMI_CMD_CLEAR_CONFIG 0x20 |
78 | #define GSMI_CMD_HANDSHAKE_TYPE 0xC1 | |
79 | ||
80 | /* Magic entry type for kernel events */ | |
81 | #define GSMI_LOG_ENTRY_TYPE_KERNEL 0xDEAD | |
82 | ||
83 | /* SMI buffers must be in 32bit physical address space */ | |
84 | struct gsmi_buf { | |
85 | u8 *start; /* start of buffer */ | |
86 | size_t length; /* length of buffer */ | |
87 | dma_addr_t handle; /* dma allocation handle */ | |
88 | u32 address; /* physical address of buffer */ | |
89 | }; | |
90 | ||
162aa53b | 91 | static struct gsmi_device { |
74c5b31c MW |
92 | struct platform_device *pdev; /* platform device */ |
93 | struct gsmi_buf *name_buf; /* variable name buffer */ | |
94 | struct gsmi_buf *data_buf; /* generic data buffer */ | |
95 | struct gsmi_buf *param_buf; /* parameter buffer */ | |
96 | spinlock_t lock; /* serialize access to SMIs */ | |
97 | u16 smi_cmd; /* SMI command port */ | |
98 | int handshake_type; /* firmware handler interlock type */ | |
99 | struct dma_pool *dma_pool; /* DMA buffer pool */ | |
100 | } gsmi_dev; | |
101 | ||
102 | /* Packed structures for communicating with the firmware */ | |
103 | struct gsmi_nvram_var_param { | |
104 | efi_guid_t guid; | |
105 | u32 name_ptr; | |
106 | u32 attributes; | |
107 | u32 data_len; | |
108 | u32 data_ptr; | |
109 | } __packed; | |
110 | ||
111 | struct gsmi_get_next_var_param { | |
112 | u8 guid[GSMI_GUID_SIZE]; | |
113 | u32 name_ptr; | |
114 | u32 name_len; | |
115 | } __packed; | |
116 | ||
117 | struct gsmi_set_eventlog_param { | |
118 | u32 data_ptr; | |
119 | u32 data_len; | |
120 | u32 type; | |
121 | } __packed; | |
122 | ||
123 | /* Event log formats */ | |
124 | struct gsmi_log_entry_type_1 { | |
125 | u16 type; | |
126 | u32 instance; | |
127 | } __packed; | |
128 | ||
74c5b31c MW |
129 | /* |
130 | * Some platforms don't have explicit SMI handshake | |
131 | * and need to wait for SMI to complete. | |
132 | */ | |
133 | #define GSMI_DEFAULT_SPINCOUNT 0x10000 | |
134 | static unsigned int spincount = GSMI_DEFAULT_SPINCOUNT; | |
135 | module_param(spincount, uint, 0600); | |
136 | MODULE_PARM_DESC(spincount, | |
137 | "The number of loop iterations to use when using the spin handshake."); | |
138 | ||
8942b2d5 FS |
139 | /* |
140 | * Platforms might not support S0ix logging in their GSMI handlers. In order to | |
141 | * avoid any side-effects of generating an SMI for S0ix logging, use the S0ix | |
142 | * related GSMI commands only for those platforms that explicitly enable this | |
143 | * option. | |
144 | */ | |
145 | static bool s0ix_logging_enable; | |
146 | module_param(s0ix_logging_enable, bool, 0600); | |
147 | ||
74c5b31c MW |
148 | static struct gsmi_buf *gsmi_buf_alloc(void) |
149 | { | |
150 | struct gsmi_buf *smibuf; | |
151 | ||
152 | smibuf = kzalloc(sizeof(*smibuf), GFP_KERNEL); | |
153 | if (!smibuf) { | |
154 | printk(KERN_ERR "gsmi: out of memory\n"); | |
155 | return NULL; | |
156 | } | |
157 | ||
158 | /* allocate buffer in 32bit address space */ | |
159 | smibuf->start = dma_pool_alloc(gsmi_dev.dma_pool, GFP_KERNEL, | |
160 | &smibuf->handle); | |
161 | if (!smibuf->start) { | |
162 | printk(KERN_ERR "gsmi: failed to allocate name buffer\n"); | |
163 | kfree(smibuf); | |
164 | return NULL; | |
165 | } | |
166 | ||
167 | /* fill in the buffer handle */ | |
168 | smibuf->length = GSMI_BUF_SIZE; | |
169 | smibuf->address = (u32)virt_to_phys(smibuf->start); | |
170 | ||
171 | return smibuf; | |
172 | } | |
173 | ||
174 | static void gsmi_buf_free(struct gsmi_buf *smibuf) | |
175 | { | |
176 | if (smibuf) { | |
177 | if (smibuf->start) | |
178 | dma_pool_free(gsmi_dev.dma_pool, smibuf->start, | |
179 | smibuf->handle); | |
180 | kfree(smibuf); | |
181 | } | |
182 | } | |
183 | ||
184 | /* | |
185 | * Make a call to gsmi func(sub). GSMI error codes are translated to | |
186 | * in-kernel errnos (0 on success, -ERRNO on error). | |
187 | */ | |
188 | static int gsmi_exec(u8 func, u8 sub) | |
189 | { | |
190 | u16 cmd = (sub << 8) | func; | |
191 | u16 result = 0; | |
192 | int rc = 0; | |
193 | ||
194 | /* | |
195 | * AH : Subfunction number | |
196 | * AL : Function number | |
197 | * EBX : Parameter block address | |
198 | * DX : SMI command port | |
199 | * | |
200 | * Three protocols here. See also the comment in gsmi_init(). | |
201 | */ | |
202 | if (gsmi_dev.handshake_type == GSMI_HANDSHAKE_CF) { | |
203 | /* | |
204 | * If handshake_type == HANDSHAKE_CF then set CF on the | |
205 | * way in and wait for the handler to clear it; this avoids | |
206 | * corrupting register state on those chipsets which have | |
207 | * a delay between writing the SMI trigger register and | |
208 | * entering SMM. | |
209 | */ | |
210 | asm volatile ( | |
211 | "stc\n" | |
212 | "outb %%al, %%dx\n" | |
213 | "1: jc 1b\n" | |
214 | : "=a" (result) | |
215 | : "0" (cmd), | |
216 | "d" (gsmi_dev.smi_cmd), | |
217 | "b" (gsmi_dev.param_buf->address) | |
218 | : "memory", "cc" | |
219 | ); | |
220 | } else if (gsmi_dev.handshake_type == GSMI_HANDSHAKE_SPIN) { | |
221 | /* | |
222 | * If handshake_type == HANDSHAKE_SPIN we spin a | |
223 | * hundred-ish usecs to ensure the SMI has triggered. | |
224 | */ | |
225 | asm volatile ( | |
226 | "outb %%al, %%dx\n" | |
227 | "1: loop 1b\n" | |
228 | : "=a" (result) | |
229 | : "0" (cmd), | |
230 | "d" (gsmi_dev.smi_cmd), | |
231 | "b" (gsmi_dev.param_buf->address), | |
232 | "c" (spincount) | |
233 | : "memory", "cc" | |
234 | ); | |
235 | } else { | |
236 | /* | |
237 | * If handshake_type == HANDSHAKE_NONE we do nothing; | |
238 | * either we don't need to or it's legacy firmware that | |
239 | * doesn't understand the CF protocol. | |
240 | */ | |
241 | asm volatile ( | |
242 | "outb %%al, %%dx\n\t" | |
243 | : "=a" (result) | |
244 | : "0" (cmd), | |
245 | "d" (gsmi_dev.smi_cmd), | |
246 | "b" (gsmi_dev.param_buf->address) | |
247 | : "memory", "cc" | |
248 | ); | |
249 | } | |
250 | ||
251 | /* check return code from SMI handler */ | |
252 | switch (result) { | |
253 | case GSMI_SUCCESS: | |
254 | break; | |
255 | case GSMI_VAR_NOT_FOUND: | |
256 | /* not really an error, but let the caller know */ | |
257 | rc = 1; | |
258 | break; | |
259 | case GSMI_INVALID_PARAMETER: | |
260 | printk(KERN_ERR "gsmi: exec 0x%04x: Invalid parameter\n", cmd); | |
261 | rc = -EINVAL; | |
262 | break; | |
263 | case GSMI_BUFFER_TOO_SMALL: | |
264 | printk(KERN_ERR "gsmi: exec 0x%04x: Buffer too small\n", cmd); | |
265 | rc = -ENOMEM; | |
266 | break; | |
267 | case GSMI_UNSUPPORTED: | |
268 | case GSMI_UNSUPPORTED2: | |
269 | if (sub != GSMI_CMD_HANDSHAKE_TYPE) | |
270 | printk(KERN_ERR "gsmi: exec 0x%04x: Not supported\n", | |
271 | cmd); | |
272 | rc = -ENOSYS; | |
273 | break; | |
274 | case GSMI_NOT_READY: | |
275 | printk(KERN_ERR "gsmi: exec 0x%04x: Not ready\n", cmd); | |
276 | rc = -EBUSY; | |
277 | break; | |
278 | case GSMI_DEVICE_ERROR: | |
279 | printk(KERN_ERR "gsmi: exec 0x%04x: Device error\n", cmd); | |
280 | rc = -EFAULT; | |
281 | break; | |
282 | case GSMI_NOT_FOUND: | |
283 | printk(KERN_ERR "gsmi: exec 0x%04x: Data not found\n", cmd); | |
284 | rc = -ENOENT; | |
285 | break; | |
286 | case GSMI_LOG_FULL: | |
287 | printk(KERN_ERR "gsmi: exec 0x%04x: Log full\n", cmd); | |
288 | rc = -ENOSPC; | |
289 | break; | |
290 | case GSMI_HANDSHAKE_CF: | |
291 | case GSMI_HANDSHAKE_SPIN: | |
292 | case GSMI_HANDSHAKE_NONE: | |
293 | rc = result; | |
294 | break; | |
295 | default: | |
296 | printk(KERN_ERR "gsmi: exec 0x%04x: Unknown error 0x%04x\n", | |
297 | cmd, result); | |
298 | rc = -ENXIO; | |
299 | } | |
300 | ||
301 | return rc; | |
302 | } | |
303 | ||
d31655ba DL |
304 | #ifdef CONFIG_EFI_VARS |
305 | ||
306 | static struct efivars efivars; | |
307 | ||
74c5b31c MW |
308 | static efi_status_t gsmi_get_variable(efi_char16_t *name, |
309 | efi_guid_t *vendor, u32 *attr, | |
310 | unsigned long *data_size, | |
311 | void *data) | |
312 | { | |
313 | struct gsmi_nvram_var_param param = { | |
314 | .name_ptr = gsmi_dev.name_buf->address, | |
315 | .data_ptr = gsmi_dev.data_buf->address, | |
316 | .data_len = (u32)*data_size, | |
317 | }; | |
318 | efi_status_t ret = EFI_SUCCESS; | |
319 | unsigned long flags; | |
a614e192 | 320 | size_t name_len = ucs2_strnlen(name, GSMI_BUF_SIZE / 2); |
74c5b31c MW |
321 | int rc; |
322 | ||
323 | if (name_len >= GSMI_BUF_SIZE / 2) | |
324 | return EFI_BAD_BUFFER_SIZE; | |
325 | ||
326 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
327 | ||
328 | /* Vendor guid */ | |
329 | memcpy(¶m.guid, vendor, sizeof(param.guid)); | |
330 | ||
331 | /* variable name, already in UTF-16 */ | |
332 | memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length); | |
333 | memcpy(gsmi_dev.name_buf->start, name, name_len * 2); | |
334 | ||
335 | /* data pointer */ | |
336 | memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length); | |
337 | ||
338 | /* parameter buffer */ | |
339 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
340 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
341 | ||
342 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_GET_NVRAM_VAR); | |
343 | if (rc < 0) { | |
344 | printk(KERN_ERR "gsmi: Get Variable failed\n"); | |
345 | ret = EFI_LOAD_ERROR; | |
346 | } else if (rc == 1) { | |
347 | /* variable was not found */ | |
348 | ret = EFI_NOT_FOUND; | |
349 | } else { | |
350 | /* Get the arguments back */ | |
351 | memcpy(¶m, gsmi_dev.param_buf->start, sizeof(param)); | |
352 | ||
353 | /* The size reported is the min of all of our buffers */ | |
d2554f50 MJ |
354 | *data_size = min_t(unsigned long, *data_size, |
355 | gsmi_dev.data_buf->length); | |
74c5b31c MW |
356 | *data_size = min_t(unsigned long, *data_size, param.data_len); |
357 | ||
358 | /* Copy data back to return buffer. */ | |
359 | memcpy(data, gsmi_dev.data_buf->start, *data_size); | |
360 | ||
361 | /* All variables are have the following attributes */ | |
362 | *attr = EFI_VARIABLE_NON_VOLATILE | | |
363 | EFI_VARIABLE_BOOTSERVICE_ACCESS | | |
364 | EFI_VARIABLE_RUNTIME_ACCESS; | |
365 | } | |
366 | ||
367 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
368 | ||
369 | return ret; | |
370 | } | |
371 | ||
372 | static efi_status_t gsmi_get_next_variable(unsigned long *name_size, | |
373 | efi_char16_t *name, | |
374 | efi_guid_t *vendor) | |
375 | { | |
376 | struct gsmi_get_next_var_param param = { | |
377 | .name_ptr = gsmi_dev.name_buf->address, | |
378 | .name_len = gsmi_dev.name_buf->length, | |
379 | }; | |
380 | efi_status_t ret = EFI_SUCCESS; | |
381 | int rc; | |
382 | unsigned long flags; | |
383 | ||
384 | /* For the moment, only support buffers that exactly match in size */ | |
385 | if (*name_size != GSMI_BUF_SIZE) | |
386 | return EFI_BAD_BUFFER_SIZE; | |
387 | ||
388 | /* Let's make sure the thing is at least null-terminated */ | |
a614e192 | 389 | if (ucs2_strnlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2) |
74c5b31c MW |
390 | return EFI_INVALID_PARAMETER; |
391 | ||
392 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
393 | ||
394 | /* guid */ | |
395 | memcpy(¶m.guid, vendor, sizeof(param.guid)); | |
396 | ||
397 | /* variable name, already in UTF-16 */ | |
398 | memcpy(gsmi_dev.name_buf->start, name, *name_size); | |
399 | ||
400 | /* parameter buffer */ | |
401 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
402 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
403 | ||
404 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_GET_NEXT_VAR); | |
405 | if (rc < 0) { | |
406 | printk(KERN_ERR "gsmi: Get Next Variable Name failed\n"); | |
407 | ret = EFI_LOAD_ERROR; | |
408 | } else if (rc == 1) { | |
409 | /* variable not found -- end of list */ | |
410 | ret = EFI_NOT_FOUND; | |
411 | } else { | |
412 | /* copy variable data back to return buffer */ | |
413 | memcpy(¶m, gsmi_dev.param_buf->start, sizeof(param)); | |
414 | ||
415 | /* Copy the name back */ | |
416 | memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE); | |
a614e192 | 417 | *name_size = ucs2_strnlen(name, GSMI_BUF_SIZE / 2) * 2; |
74c5b31c MW |
418 | |
419 | /* copy guid to return buffer */ | |
420 | memcpy(vendor, ¶m.guid, sizeof(param.guid)); | |
421 | ret = EFI_SUCCESS; | |
422 | } | |
423 | ||
424 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
425 | ||
426 | return ret; | |
427 | } | |
428 | ||
429 | static efi_status_t gsmi_set_variable(efi_char16_t *name, | |
430 | efi_guid_t *vendor, | |
a88769cd | 431 | u32 attr, |
74c5b31c MW |
432 | unsigned long data_size, |
433 | void *data) | |
434 | { | |
435 | struct gsmi_nvram_var_param param = { | |
436 | .name_ptr = gsmi_dev.name_buf->address, | |
437 | .data_ptr = gsmi_dev.data_buf->address, | |
438 | .data_len = (u32)data_size, | |
439 | .attributes = EFI_VARIABLE_NON_VOLATILE | | |
440 | EFI_VARIABLE_BOOTSERVICE_ACCESS | | |
441 | EFI_VARIABLE_RUNTIME_ACCESS, | |
442 | }; | |
a614e192 | 443 | size_t name_len = ucs2_strnlen(name, GSMI_BUF_SIZE / 2); |
74c5b31c MW |
444 | efi_status_t ret = EFI_SUCCESS; |
445 | int rc; | |
446 | unsigned long flags; | |
447 | ||
448 | if (name_len >= GSMI_BUF_SIZE / 2) | |
449 | return EFI_BAD_BUFFER_SIZE; | |
450 | ||
451 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
452 | ||
453 | /* guid */ | |
454 | memcpy(¶m.guid, vendor, sizeof(param.guid)); | |
455 | ||
456 | /* variable name, already in UTF-16 */ | |
457 | memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length); | |
458 | memcpy(gsmi_dev.name_buf->start, name, name_len * 2); | |
459 | ||
460 | /* data pointer */ | |
461 | memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length); | |
462 | memcpy(gsmi_dev.data_buf->start, data, data_size); | |
463 | ||
464 | /* parameter buffer */ | |
465 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
466 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
467 | ||
468 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_NVRAM_VAR); | |
469 | if (rc < 0) { | |
470 | printk(KERN_ERR "gsmi: Set Variable failed\n"); | |
471 | ret = EFI_INVALID_PARAMETER; | |
472 | } | |
473 | ||
474 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
475 | ||
476 | return ret; | |
477 | } | |
478 | ||
479 | static const struct efivar_operations efivar_ops = { | |
480 | .get_variable = gsmi_get_variable, | |
481 | .set_variable = gsmi_set_variable, | |
482 | .get_next_variable = gsmi_get_next_variable, | |
483 | }; | |
484 | ||
d31655ba DL |
485 | #endif /* CONFIG_EFI_VARS */ |
486 | ||
74c5b31c MW |
487 | static ssize_t eventlog_write(struct file *filp, struct kobject *kobj, |
488 | struct bin_attribute *bin_attr, | |
489 | char *buf, loff_t pos, size_t count) | |
490 | { | |
491 | struct gsmi_set_eventlog_param param = { | |
492 | .data_ptr = gsmi_dev.data_buf->address, | |
493 | }; | |
494 | int rc = 0; | |
495 | unsigned long flags; | |
496 | ||
497 | /* Pull the type out */ | |
498 | if (count < sizeof(u32)) | |
499 | return -EINVAL; | |
500 | param.type = *(u32 *)buf; | |
74c5b31c MW |
501 | buf += sizeof(u32); |
502 | ||
503 | /* The remaining buffer is the data payload */ | |
655603de | 504 | if ((count - sizeof(u32)) > gsmi_dev.data_buf->length) |
74c5b31c MW |
505 | return -EINVAL; |
506 | param.data_len = count - sizeof(u32); | |
507 | ||
508 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
509 | ||
510 | /* data pointer */ | |
511 | memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length); | |
512 | memcpy(gsmi_dev.data_buf->start, buf, param.data_len); | |
513 | ||
514 | /* parameter buffer */ | |
515 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
516 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
517 | ||
518 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_EVENT_LOG); | |
519 | if (rc < 0) | |
520 | printk(KERN_ERR "gsmi: Set Event Log failed\n"); | |
521 | ||
522 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
523 | ||
655603de | 524 | return (rc == 0) ? count : rc; |
74c5b31c MW |
525 | |
526 | } | |
527 | ||
528 | static struct bin_attribute eventlog_bin_attr = { | |
529 | .attr = {.name = "append_to_eventlog", .mode = 0200}, | |
530 | .write = eventlog_write, | |
531 | }; | |
532 | ||
533 | static ssize_t gsmi_clear_eventlog_store(struct kobject *kobj, | |
534 | struct kobj_attribute *attr, | |
535 | const char *buf, size_t count) | |
536 | { | |
537 | int rc; | |
538 | unsigned long flags; | |
539 | unsigned long val; | |
540 | struct { | |
541 | u32 percentage; | |
542 | u32 data_type; | |
543 | } param; | |
544 | ||
20d0e570 | 545 | rc = kstrtoul(buf, 0, &val); |
74c5b31c MW |
546 | if (rc) |
547 | return rc; | |
548 | ||
549 | /* | |
550 | * Value entered is a percentage, 0 through 100, anything else | |
551 | * is invalid. | |
552 | */ | |
553 | if (val > 100) | |
554 | return -EINVAL; | |
555 | ||
556 | /* data_type here selects the smbios event log. */ | |
557 | param.percentage = val; | |
558 | param.data_type = 0; | |
559 | ||
560 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
561 | ||
562 | /* parameter buffer */ | |
563 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
564 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
565 | ||
566 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_CLEAR_EVENT_LOG); | |
567 | ||
568 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
569 | ||
570 | if (rc) | |
571 | return rc; | |
572 | return count; | |
573 | } | |
574 | ||
575 | static struct kobj_attribute gsmi_clear_eventlog_attr = { | |
576 | .attr = {.name = "clear_eventlog", .mode = 0200}, | |
577 | .store = gsmi_clear_eventlog_store, | |
578 | }; | |
579 | ||
580 | static ssize_t gsmi_clear_config_store(struct kobject *kobj, | |
581 | struct kobj_attribute *attr, | |
582 | const char *buf, size_t count) | |
583 | { | |
584 | int rc; | |
585 | unsigned long flags; | |
586 | ||
587 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
588 | ||
589 | /* clear parameter buffer */ | |
590 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
591 | ||
592 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_CLEAR_CONFIG); | |
593 | ||
594 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
595 | ||
596 | if (rc) | |
597 | return rc; | |
598 | return count; | |
599 | } | |
600 | ||
601 | static struct kobj_attribute gsmi_clear_config_attr = { | |
602 | .attr = {.name = "clear_config", .mode = 0200}, | |
603 | .store = gsmi_clear_config_store, | |
604 | }; | |
605 | ||
606 | static const struct attribute *gsmi_attrs[] = { | |
607 | &gsmi_clear_config_attr.attr, | |
608 | &gsmi_clear_eventlog_attr.attr, | |
609 | NULL, | |
610 | }; | |
611 | ||
612 | static int gsmi_shutdown_reason(int reason) | |
613 | { | |
614 | struct gsmi_log_entry_type_1 entry = { | |
615 | .type = GSMI_LOG_ENTRY_TYPE_KERNEL, | |
616 | .instance = reason, | |
617 | }; | |
618 | struct gsmi_set_eventlog_param param = { | |
619 | .data_len = sizeof(entry), | |
620 | .type = 1, | |
621 | }; | |
622 | static int saved_reason; | |
623 | int rc = 0; | |
624 | unsigned long flags; | |
625 | ||
626 | /* avoid duplicate entries in the log */ | |
627 | if (saved_reason & (1 << reason)) | |
628 | return 0; | |
629 | ||
630 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
631 | ||
632 | saved_reason |= (1 << reason); | |
633 | ||
634 | /* data pointer */ | |
635 | memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length); | |
636 | memcpy(gsmi_dev.data_buf->start, &entry, sizeof(entry)); | |
637 | ||
638 | /* parameter buffer */ | |
639 | param.data_ptr = gsmi_dev.data_buf->address; | |
640 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
641 | memcpy(gsmi_dev.param_buf->start, ¶m, sizeof(param)); | |
642 | ||
643 | rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_EVENT_LOG); | |
644 | ||
645 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
646 | ||
647 | if (rc < 0) | |
648 | printk(KERN_ERR "gsmi: Log Shutdown Reason failed\n"); | |
649 | else | |
650 | printk(KERN_EMERG "gsmi: Log Shutdown Reason 0x%02x\n", | |
651 | reason); | |
652 | ||
653 | return rc; | |
654 | } | |
655 | ||
656 | static int gsmi_reboot_callback(struct notifier_block *nb, | |
657 | unsigned long reason, void *arg) | |
658 | { | |
659 | gsmi_shutdown_reason(GSMI_SHUTDOWN_CLEAN); | |
660 | return NOTIFY_DONE; | |
661 | } | |
662 | ||
663 | static struct notifier_block gsmi_reboot_notifier = { | |
664 | .notifier_call = gsmi_reboot_callback | |
665 | }; | |
666 | ||
667 | static int gsmi_die_callback(struct notifier_block *nb, | |
668 | unsigned long reason, void *arg) | |
669 | { | |
670 | if (reason == DIE_OOPS) | |
671 | gsmi_shutdown_reason(GSMI_SHUTDOWN_OOPS); | |
672 | return NOTIFY_DONE; | |
673 | } | |
674 | ||
675 | static struct notifier_block gsmi_die_notifier = { | |
676 | .notifier_call = gsmi_die_callback | |
677 | }; | |
678 | ||
679 | static int gsmi_panic_callback(struct notifier_block *nb, | |
680 | unsigned long reason, void *arg) | |
681 | { | |
682 | gsmi_shutdown_reason(GSMI_SHUTDOWN_PANIC); | |
683 | return NOTIFY_DONE; | |
684 | } | |
685 | ||
686 | static struct notifier_block gsmi_panic_notifier = { | |
687 | .notifier_call = gsmi_panic_callback, | |
688 | }; | |
689 | ||
690 | /* | |
691 | * This hash function was blatantly copied from include/linux/hash.h. | |
692 | * It is used by this driver to obfuscate a board name that requires a | |
693 | * quirk within this driver. | |
694 | * | |
695 | * Please do not remove this copy of the function as any changes to the | |
696 | * global utility hash_64() function would break this driver's ability | |
697 | * to identify a board and provide the appropriate quirk -- mikew@google.com | |
698 | */ | |
699 | static u64 __init local_hash_64(u64 val, unsigned bits) | |
700 | { | |
701 | u64 hash = val; | |
702 | ||
703 | /* Sigh, gcc can't optimise this alone like it does for 32 bits. */ | |
704 | u64 n = hash; | |
705 | n <<= 18; | |
706 | hash -= n; | |
707 | n <<= 33; | |
708 | hash -= n; | |
709 | n <<= 3; | |
710 | hash += n; | |
711 | n <<= 3; | |
712 | hash -= n; | |
713 | n <<= 4; | |
714 | hash += n; | |
715 | n <<= 2; | |
716 | hash += n; | |
717 | ||
718 | /* High bits are more random, so use them. */ | |
719 | return hash >> (64 - bits); | |
720 | } | |
721 | ||
722 | static u32 __init hash_oem_table_id(char s[8]) | |
723 | { | |
724 | u64 input; | |
725 | memcpy(&input, s, 8); | |
726 | return local_hash_64(input, 32); | |
727 | } | |
728 | ||
6faadbbb | 729 | static const struct dmi_system_id gsmi_dmi_table[] __initconst = { |
74c5b31c MW |
730 | { |
731 | .ident = "Google Board", | |
732 | .matches = { | |
733 | DMI_MATCH(DMI_BOARD_VENDOR, "Google, Inc."), | |
734 | }, | |
735 | }, | |
255d7447 DL |
736 | { |
737 | .ident = "Coreboot Firmware", | |
738 | .matches = { | |
739 | DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"), | |
740 | }, | |
741 | }, | |
74c5b31c MW |
742 | {} |
743 | }; | |
744 | MODULE_DEVICE_TABLE(dmi, gsmi_dmi_table); | |
745 | ||
746 | static __init int gsmi_system_valid(void) | |
747 | { | |
748 | u32 hash; | |
749 | ||
750 | if (!dmi_check_system(gsmi_dmi_table)) | |
751 | return -ENODEV; | |
752 | ||
753 | /* | |
754 | * Only newer firmware supports the gsmi interface. All older | |
755 | * firmware that didn't support this interface used to plug the | |
756 | * table name in the first four bytes of the oem_table_id field. | |
757 | * Newer firmware doesn't do that though, so use that as the | |
758 | * discriminant factor. We have to do this in order to | |
759 | * whitewash our board names out of the public driver. | |
760 | */ | |
761 | if (!strncmp(acpi_gbl_FADT.header.oem_table_id, "FACP", 4)) { | |
762 | printk(KERN_INFO "gsmi: Board is too old\n"); | |
763 | return -ENODEV; | |
764 | } | |
765 | ||
766 | /* Disable on board with 1.0 BIOS due to Google bug 2602657 */ | |
767 | hash = hash_oem_table_id(acpi_gbl_FADT.header.oem_table_id); | |
768 | if (hash == QUIRKY_BOARD_HASH) { | |
769 | const char *bios_ver = dmi_get_system_info(DMI_BIOS_VERSION); | |
770 | if (strncmp(bios_ver, "1.0", 3) == 0) { | |
771 | pr_info("gsmi: disabled on this board's BIOS %s\n", | |
772 | bios_ver); | |
773 | return -ENODEV; | |
774 | } | |
775 | } | |
776 | ||
777 | /* check for valid SMI command port in ACPI FADT */ | |
778 | if (acpi_gbl_FADT.smi_command == 0) { | |
779 | pr_info("gsmi: missing smi_command\n"); | |
780 | return -ENODEV; | |
781 | } | |
782 | ||
783 | /* Found */ | |
784 | return 0; | |
785 | } | |
786 | ||
787 | static struct kobject *gsmi_kobj; | |
74c5b31c | 788 | |
536dc1eb RK |
789 | static const struct platform_device_info gsmi_dev_info = { |
790 | .name = "gsmi", | |
791 | .id = -1, | |
792 | /* SMI callbacks require 32bit addresses */ | |
793 | .dma_mask = DMA_BIT_MASK(32), | |
794 | }; | |
795 | ||
8942b2d5 FS |
796 | #ifdef CONFIG_PM |
797 | static void gsmi_log_s0ix_info(u8 cmd) | |
798 | { | |
799 | unsigned long flags; | |
800 | ||
801 | /* | |
802 | * If platform has not enabled S0ix logging, then no action is | |
803 | * necessary. | |
804 | */ | |
805 | if (!s0ix_logging_enable) | |
806 | return; | |
807 | ||
808 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
809 | ||
810 | memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length); | |
811 | ||
812 | gsmi_exec(GSMI_CALLBACK, cmd); | |
813 | ||
814 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
815 | } | |
816 | ||
817 | static int gsmi_log_s0ix_suspend(struct device *dev) | |
818 | { | |
819 | /* | |
820 | * If system is not suspending via firmware using the standard ACPI Sx | |
821 | * types, then make a GSMI call to log the suspend info. | |
822 | */ | |
823 | if (!pm_suspend_via_firmware()) | |
824 | gsmi_log_s0ix_info(GSMI_CMD_LOG_S0IX_SUSPEND); | |
825 | ||
826 | /* | |
827 | * Always return success, since we do not want suspend | |
828 | * to fail just because of logging failure. | |
829 | */ | |
830 | return 0; | |
831 | } | |
832 | ||
833 | static int gsmi_log_s0ix_resume(struct device *dev) | |
834 | { | |
835 | /* | |
836 | * If system did not resume via firmware, then make a GSMI call to log | |
837 | * the resume info and wake source. | |
838 | */ | |
839 | if (!pm_resume_via_firmware()) | |
840 | gsmi_log_s0ix_info(GSMI_CMD_LOG_S0IX_RESUME); | |
841 | ||
842 | /* | |
843 | * Always return success, since we do not want resume | |
844 | * to fail just because of logging failure. | |
845 | */ | |
846 | return 0; | |
847 | } | |
848 | ||
849 | static const struct dev_pm_ops gsmi_pm_ops = { | |
850 | .suspend_noirq = gsmi_log_s0ix_suspend, | |
851 | .resume_noirq = gsmi_log_s0ix_resume, | |
852 | }; | |
853 | ||
854 | static int gsmi_platform_driver_probe(struct platform_device *dev) | |
855 | { | |
856 | return 0; | |
857 | } | |
858 | ||
859 | static struct platform_driver gsmi_driver_info = { | |
860 | .driver = { | |
861 | .name = "gsmi", | |
862 | .pm = &gsmi_pm_ops, | |
863 | }, | |
864 | .probe = gsmi_platform_driver_probe, | |
865 | }; | |
866 | #endif | |
867 | ||
74c5b31c MW |
868 | static __init int gsmi_init(void) |
869 | { | |
870 | unsigned long flags; | |
871 | int ret; | |
872 | ||
873 | ret = gsmi_system_valid(); | |
874 | if (ret) | |
875 | return ret; | |
876 | ||
877 | gsmi_dev.smi_cmd = acpi_gbl_FADT.smi_command; | |
878 | ||
8942b2d5 FS |
879 | #ifdef CONFIG_PM |
880 | ret = platform_driver_register(&gsmi_driver_info); | |
881 | if (unlikely(ret)) { | |
882 | printk(KERN_ERR "gsmi: unable to register platform driver\n"); | |
883 | return ret; | |
884 | } | |
885 | #endif | |
886 | ||
74c5b31c | 887 | /* register device */ |
536dc1eb | 888 | gsmi_dev.pdev = platform_device_register_full(&gsmi_dev_info); |
74c5b31c MW |
889 | if (IS_ERR(gsmi_dev.pdev)) { |
890 | printk(KERN_ERR "gsmi: unable to register platform device\n"); | |
891 | return PTR_ERR(gsmi_dev.pdev); | |
892 | } | |
893 | ||
894 | /* SMI access needs to be serialized */ | |
895 | spin_lock_init(&gsmi_dev.lock); | |
896 | ||
74c5b31c MW |
897 | ret = -ENOMEM; |
898 | gsmi_dev.dma_pool = dma_pool_create("gsmi", &gsmi_dev.pdev->dev, | |
899 | GSMI_BUF_SIZE, GSMI_BUF_ALIGN, 0); | |
900 | if (!gsmi_dev.dma_pool) | |
901 | goto out_err; | |
902 | ||
903 | /* | |
904 | * pre-allocate buffers because sometimes we are called when | |
905 | * this is not feasible: oops, panic, die, mce, etc | |
906 | */ | |
907 | gsmi_dev.name_buf = gsmi_buf_alloc(); | |
908 | if (!gsmi_dev.name_buf) { | |
909 | printk(KERN_ERR "gsmi: failed to allocate name buffer\n"); | |
910 | goto out_err; | |
911 | } | |
912 | ||
913 | gsmi_dev.data_buf = gsmi_buf_alloc(); | |
914 | if (!gsmi_dev.data_buf) { | |
915 | printk(KERN_ERR "gsmi: failed to allocate data buffer\n"); | |
916 | goto out_err; | |
917 | } | |
918 | ||
919 | gsmi_dev.param_buf = gsmi_buf_alloc(); | |
920 | if (!gsmi_dev.param_buf) { | |
921 | printk(KERN_ERR "gsmi: failed to allocate param buffer\n"); | |
922 | goto out_err; | |
923 | } | |
924 | ||
925 | /* | |
926 | * Determine type of handshake used to serialize the SMI | |
927 | * entry. See also gsmi_exec(). | |
928 | * | |
929 | * There's a "behavior" present on some chipsets where writing the | |
930 | * SMI trigger register in the southbridge doesn't result in an | |
931 | * immediate SMI. Rather, the processor can execute "a few" more | |
932 | * instructions before the SMI takes effect. To ensure synchronous | |
933 | * behavior, implement a handshake between the kernel driver and the | |
934 | * firmware handler to spin until released. This ioctl determines | |
935 | * the type of handshake. | |
936 | * | |
937 | * NONE: The firmware handler does not implement any | |
938 | * handshake. Either it doesn't need to, or it's legacy firmware | |
939 | * that doesn't know it needs to and never will. | |
940 | * | |
941 | * CF: The firmware handler will clear the CF in the saved | |
942 | * state before returning. The driver may set the CF and test for | |
943 | * it to clear before proceeding. | |
944 | * | |
945 | * SPIN: The firmware handler does not implement any handshake | |
946 | * but the driver should spin for a hundred or so microseconds | |
947 | * to ensure the SMI has triggered. | |
948 | * | |
949 | * Finally, the handler will return -ENOSYS if | |
950 | * GSMI_CMD_HANDSHAKE_TYPE is unimplemented, which implies | |
951 | * HANDSHAKE_NONE. | |
952 | */ | |
953 | spin_lock_irqsave(&gsmi_dev.lock, flags); | |
954 | gsmi_dev.handshake_type = GSMI_HANDSHAKE_SPIN; | |
955 | gsmi_dev.handshake_type = | |
956 | gsmi_exec(GSMI_CALLBACK, GSMI_CMD_HANDSHAKE_TYPE); | |
957 | if (gsmi_dev.handshake_type == -ENOSYS) | |
958 | gsmi_dev.handshake_type = GSMI_HANDSHAKE_NONE; | |
959 | spin_unlock_irqrestore(&gsmi_dev.lock, flags); | |
960 | ||
961 | /* Remove and clean up gsmi if the handshake could not complete. */ | |
962 | if (gsmi_dev.handshake_type == -ENXIO) { | |
963 | printk(KERN_INFO "gsmi version " DRIVER_VERSION | |
964 | " failed to load\n"); | |
965 | ret = -ENODEV; | |
966 | goto out_err; | |
967 | } | |
968 | ||
74c5b31c MW |
969 | /* Register in the firmware directory */ |
970 | ret = -ENOMEM; | |
971 | gsmi_kobj = kobject_create_and_add("gsmi", firmware_kobj); | |
972 | if (!gsmi_kobj) { | |
973 | printk(KERN_INFO "gsmi: Failed to create firmware kobj\n"); | |
974 | goto out_err; | |
975 | } | |
976 | ||
977 | /* Setup eventlog access */ | |
978 | ret = sysfs_create_bin_file(gsmi_kobj, &eventlog_bin_attr); | |
979 | if (ret) { | |
980 | printk(KERN_INFO "gsmi: Failed to setup eventlog"); | |
981 | goto out_err; | |
982 | } | |
983 | ||
984 | /* Other attributes */ | |
985 | ret = sysfs_create_files(gsmi_kobj, gsmi_attrs); | |
986 | if (ret) { | |
987 | printk(KERN_INFO "gsmi: Failed to add attrs"); | |
1e4de816 | 988 | goto out_remove_bin_file; |
74c5b31c MW |
989 | } |
990 | ||
d31655ba | 991 | #ifdef CONFIG_EFI_VARS |
e14ab23d | 992 | ret = efivars_register(&efivars, &efivar_ops, gsmi_kobj); |
1e4de816 | 993 | if (ret) { |
74c5b31c | 994 | printk(KERN_INFO "gsmi: Failed to register efivars\n"); |
d31655ba DL |
995 | sysfs_remove_files(gsmi_kobj, gsmi_attrs); |
996 | goto out_remove_bin_file; | |
74c5b31c | 997 | } |
d31655ba | 998 | #endif |
74c5b31c MW |
999 | |
1000 | register_reboot_notifier(&gsmi_reboot_notifier); | |
1001 | register_die_notifier(&gsmi_die_notifier); | |
1002 | atomic_notifier_chain_register(&panic_notifier_list, | |
1003 | &gsmi_panic_notifier); | |
1004 | ||
1e4de816 AL |
1005 | printk(KERN_INFO "gsmi version " DRIVER_VERSION " loaded\n"); |
1006 | ||
74c5b31c MW |
1007 | return 0; |
1008 | ||
1e4de816 AL |
1009 | out_remove_bin_file: |
1010 | sysfs_remove_bin_file(gsmi_kobj, &eventlog_bin_attr); | |
1011 | out_err: | |
74c5b31c MW |
1012 | kobject_put(gsmi_kobj); |
1013 | gsmi_buf_free(gsmi_dev.param_buf); | |
1014 | gsmi_buf_free(gsmi_dev.data_buf); | |
1015 | gsmi_buf_free(gsmi_dev.name_buf); | |
d520dd1f | 1016 | dma_pool_destroy(gsmi_dev.dma_pool); |
74c5b31c MW |
1017 | platform_device_unregister(gsmi_dev.pdev); |
1018 | pr_info("gsmi: failed to load: %d\n", ret); | |
1019 | return ret; | |
1020 | } | |
1021 | ||
1022 | static void __exit gsmi_exit(void) | |
1023 | { | |
1024 | unregister_reboot_notifier(&gsmi_reboot_notifier); | |
1025 | unregister_die_notifier(&gsmi_die_notifier); | |
1026 | atomic_notifier_chain_unregister(&panic_notifier_list, | |
1027 | &gsmi_panic_notifier); | |
d31655ba | 1028 | #ifdef CONFIG_EFI_VARS |
e14ab23d | 1029 | efivars_unregister(&efivars); |
d31655ba | 1030 | #endif |
74c5b31c | 1031 | |
1e4de816 AL |
1032 | sysfs_remove_files(gsmi_kobj, gsmi_attrs); |
1033 | sysfs_remove_bin_file(gsmi_kobj, &eventlog_bin_attr); | |
74c5b31c MW |
1034 | kobject_put(gsmi_kobj); |
1035 | gsmi_buf_free(gsmi_dev.param_buf); | |
1036 | gsmi_buf_free(gsmi_dev.data_buf); | |
1037 | gsmi_buf_free(gsmi_dev.name_buf); | |
1038 | dma_pool_destroy(gsmi_dev.dma_pool); | |
1039 | platform_device_unregister(gsmi_dev.pdev); | |
1040 | } | |
1041 | ||
1042 | module_init(gsmi_init); | |
1043 | module_exit(gsmi_exit); | |
1044 | ||
1045 | MODULE_AUTHOR("Google, Inc."); | |
1046 | MODULE_LICENSE("GPL"); |