1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ipmi_smic_sm.c
4  *
5  * The state-machine driver for an IPMI SMIC driver
6  *
7  * It started as a copy of Corey Minyard's driver for the KSC interface
8  * and the kernel patch "mmcdev-patch-245" by HP
9  *
10  * modified by:	Hannes Schulz <schulz@schwaar.com>
11  *		ipmi@schwaar.com
12  *
13  *
14  * Corey Minyard's driver for the KSC interface has the following
15  * copyright notice:
16  *   Copyright 2002 MontaVista Software Inc.
17  *
18  * the kernel patch "mmcdev-patch-245" by HP has the following
19  * copyright notice:
20  * (c) Copyright 2001 Grant Grundler (c) Copyright
21  * 2001 Hewlett-Packard Company
22  */
23 
24 #include <linux/kernel.h> /* For printk. */
25 #include <linux/string.h>
26 #include <linux/module.h>
27 #include <linux/moduleparam.h>
28 #include <linux/ipmi_msgdefs.h>		/* for completion codes */
29 #include "ipmi_si_sm.h"
30 
31 /* smic_debug is a bit-field
32  *	SMIC_DEBUG_ENABLE -	turned on for now
33  *	SMIC_DEBUG_MSG -	commands and their responses
34  *	SMIC_DEBUG_STATES -	state machine
35 */
36 #define SMIC_DEBUG_STATES	4
37 #define SMIC_DEBUG_MSG		2
38 #define	SMIC_DEBUG_ENABLE	1
39 
40 static int smic_debug = 1;
41 module_param(smic_debug, int, 0644);
42 MODULE_PARM_DESC(smic_debug, "debug bitmask, 1=enable, 2=messages, 4=states");
43 
44 enum smic_states {
45 	SMIC_IDLE,
46 	SMIC_START_OP,
47 	SMIC_OP_OK,
48 	SMIC_WRITE_START,
49 	SMIC_WRITE_NEXT,
50 	SMIC_WRITE_END,
51 	SMIC_WRITE2READ,
52 	SMIC_READ_START,
53 	SMIC_READ_NEXT,
54 	SMIC_READ_END,
55 	SMIC_HOSED
56 };
57 
58 #define MAX_SMIC_READ_SIZE 80
59 #define MAX_SMIC_WRITE_SIZE 80
60 #define SMIC_MAX_ERROR_RETRIES 3
61 
62 /* Timeouts in microseconds. */
63 #define SMIC_RETRY_TIMEOUT (2*USEC_PER_SEC)
64 
65 /* SMIC Flags Register Bits */
66 #define SMIC_RX_DATA_READY	0x80
67 #define SMIC_TX_DATA_READY	0x40
68 
69 /*
70  * SMIC_SMI and SMIC_EVM_DATA_AVAIL are only used by
71  * a few systems, and then only by Systems Management
72  * Interrupts, not by the OS.  Always ignore these bits.
73  *
74  */
75 #define SMIC_SMI		0x10
76 #define SMIC_EVM_DATA_AVAIL	0x08
77 #define SMIC_SMS_DATA_AVAIL	0x04
78 #define SMIC_FLAG_BSY		0x01
79 
80 /* SMIC Error Codes */
81 #define	EC_NO_ERROR		0x00
82 #define	EC_ABORTED		0x01
83 #define	EC_ILLEGAL_CONTROL	0x02
84 #define	EC_NO_RESPONSE		0x03
85 #define	EC_ILLEGAL_COMMAND	0x04
86 #define	EC_BUFFER_FULL		0x05
87 
88 struct si_sm_data {
89 	enum smic_states state;
90 	struct si_sm_io *io;
91 	unsigned char	 write_data[MAX_SMIC_WRITE_SIZE];
92 	int		 write_pos;
93 	int		 write_count;
94 	int		 orig_write_count;
95 	unsigned char	 read_data[MAX_SMIC_READ_SIZE];
96 	int		 read_pos;
97 	int		 truncated;
98 	unsigned int	 error_retries;
99 	long		 smic_timeout;
100 };
101 
init_smic_data(struct si_sm_data * smic,struct si_sm_io * io)102 static unsigned int init_smic_data(struct si_sm_data *smic,
103 				   struct si_sm_io *io)
104 {
105 	smic->state = SMIC_IDLE;
106 	smic->io = io;
107 	smic->write_pos = 0;
108 	smic->write_count = 0;
109 	smic->orig_write_count = 0;
110 	smic->read_pos = 0;
111 	smic->error_retries = 0;
112 	smic->truncated = 0;
113 	smic->smic_timeout = SMIC_RETRY_TIMEOUT;
114 
115 	/* We use 3 bytes of I/O. */
116 	return 3;
117 }
118 
start_smic_transaction(struct si_sm_data * smic,unsigned char * data,unsigned int size)119 static int start_smic_transaction(struct si_sm_data *smic,
120 				  unsigned char *data, unsigned int size)
121 {
122 	unsigned int i;
123 
124 	if (size < 2)
125 		return IPMI_REQ_LEN_INVALID_ERR;
126 	if (size > MAX_SMIC_WRITE_SIZE)
127 		return IPMI_REQ_LEN_EXCEEDED_ERR;
128 
129 	if ((smic->state != SMIC_IDLE) && (smic->state != SMIC_HOSED))
130 		return IPMI_NOT_IN_MY_STATE_ERR;
131 
132 	if (smic_debug & SMIC_DEBUG_MSG) {
133 		printk(KERN_DEBUG "start_smic_transaction -");
134 		for (i = 0; i < size; i++)
135 			pr_cont(" %02x", data[i]);
136 		pr_cont("\n");
137 	}
138 	smic->error_retries = 0;
139 	memcpy(smic->write_data, data, size);
140 	smic->write_count = size;
141 	smic->orig_write_count = size;
142 	smic->write_pos = 0;
143 	smic->read_pos = 0;
144 	smic->state = SMIC_START_OP;
145 	smic->smic_timeout = SMIC_RETRY_TIMEOUT;
146 	return 0;
147 }
148 
smic_get_result(struct si_sm_data * smic,unsigned char * data,unsigned int length)149 static int smic_get_result(struct si_sm_data *smic,
150 			   unsigned char *data, unsigned int length)
151 {
152 	int i;
153 
154 	if (smic_debug & SMIC_DEBUG_MSG) {
155 		printk(KERN_DEBUG "smic_get result -");
156 		for (i = 0; i < smic->read_pos; i++)
157 			pr_cont(" %02x", smic->read_data[i]);
158 		pr_cont("\n");
159 	}
160 	if (length < smic->read_pos) {
161 		smic->read_pos = length;
162 		smic->truncated = 1;
163 	}
164 	memcpy(data, smic->read_data, smic->read_pos);
165 
166 	if ((length >= 3) && (smic->read_pos < 3)) {
167 		data[2] = IPMI_ERR_UNSPECIFIED;
168 		smic->read_pos = 3;
169 	}
170 	if (smic->truncated) {
171 		data[2] = IPMI_ERR_MSG_TRUNCATED;
172 		smic->truncated = 0;
173 	}
174 	return smic->read_pos;
175 }
176 
read_smic_flags(struct si_sm_data * smic)177 static inline unsigned char read_smic_flags(struct si_sm_data *smic)
178 {
179 	return smic->io->inputb(smic->io, 2);
180 }
181 
read_smic_status(struct si_sm_data * smic)182 static inline unsigned char read_smic_status(struct si_sm_data *smic)
183 {
184 	return smic->io->inputb(smic->io, 1);
185 }
186 
read_smic_data(struct si_sm_data * smic)187 static inline unsigned char read_smic_data(struct si_sm_data *smic)
188 {
189 	return smic->io->inputb(smic->io, 0);
190 }
191 
write_smic_flags(struct si_sm_data * smic,unsigned char flags)192 static inline void write_smic_flags(struct si_sm_data *smic,
193 				    unsigned char   flags)
194 {
195 	smic->io->outputb(smic->io, 2, flags);
196 }
197 
write_smic_control(struct si_sm_data * smic,unsigned char control)198 static inline void write_smic_control(struct si_sm_data *smic,
199 				      unsigned char   control)
200 {
201 	smic->io->outputb(smic->io, 1, control);
202 }
203 
write_si_sm_data(struct si_sm_data * smic,unsigned char data)204 static inline void write_si_sm_data(struct si_sm_data *smic,
205 				    unsigned char   data)
206 {
207 	smic->io->outputb(smic->io, 0, data);
208 }
209 
start_error_recovery(struct si_sm_data * smic,char * reason)210 static inline void start_error_recovery(struct si_sm_data *smic, char *reason)
211 {
212 	(smic->error_retries)++;
213 	if (smic->error_retries > SMIC_MAX_ERROR_RETRIES) {
214 		if (smic_debug & SMIC_DEBUG_ENABLE)
215 			pr_warn("ipmi_smic_drv: smic hosed: %s\n", reason);
216 		smic->state = SMIC_HOSED;
217 	} else {
218 		smic->write_count = smic->orig_write_count;
219 		smic->write_pos = 0;
220 		smic->read_pos = 0;
221 		smic->state = SMIC_START_OP;
222 		smic->smic_timeout = SMIC_RETRY_TIMEOUT;
223 	}
224 }
225 
write_next_byte(struct si_sm_data * smic)226 static inline void write_next_byte(struct si_sm_data *smic)
227 {
228 	write_si_sm_data(smic, smic->write_data[smic->write_pos]);
229 	(smic->write_pos)++;
230 	(smic->write_count)--;
231 }
232 
read_next_byte(struct si_sm_data * smic)233 static inline void read_next_byte(struct si_sm_data *smic)
234 {
235 	if (smic->read_pos >= MAX_SMIC_READ_SIZE) {
236 		read_smic_data(smic);
237 		smic->truncated = 1;
238 	} else {
239 		smic->read_data[smic->read_pos] = read_smic_data(smic);
240 		smic->read_pos++;
241 	}
242 }
243 
244 /*  SMIC Control/Status Code Components */
245 #define	SMIC_GET_STATUS		0x00	/* Control form's name */
246 #define	SMIC_READY		0x00	/* Status  form's name */
247 #define	SMIC_WR_START		0x01	/* Unified Control/Status names... */
248 #define	SMIC_WR_NEXT		0x02
249 #define	SMIC_WR_END		0x03
250 #define	SMIC_RD_START		0x04
251 #define	SMIC_RD_NEXT		0x05
252 #define	SMIC_RD_END		0x06
253 #define	SMIC_CODE_MASK		0x0f
254 
255 #define	SMIC_CONTROL		0x00
256 #define	SMIC_STATUS		0x80
257 #define	SMIC_CS_MASK		0x80
258 
259 #define	SMIC_SMS		0x40
260 #define	SMIC_SMM		0x60
261 #define	SMIC_STREAM_MASK	0x60
262 
263 /*  SMIC Control Codes */
264 #define	SMIC_CC_SMS_GET_STATUS	(SMIC_CONTROL|SMIC_SMS|SMIC_GET_STATUS)
265 #define	SMIC_CC_SMS_WR_START	(SMIC_CONTROL|SMIC_SMS|SMIC_WR_START)
266 #define	SMIC_CC_SMS_WR_NEXT	(SMIC_CONTROL|SMIC_SMS|SMIC_WR_NEXT)
267 #define	SMIC_CC_SMS_WR_END	(SMIC_CONTROL|SMIC_SMS|SMIC_WR_END)
268 #define	SMIC_CC_SMS_RD_START	(SMIC_CONTROL|SMIC_SMS|SMIC_RD_START)
269 #define	SMIC_CC_SMS_RD_NEXT	(SMIC_CONTROL|SMIC_SMS|SMIC_RD_NEXT)
270 #define	SMIC_CC_SMS_RD_END	(SMIC_CONTROL|SMIC_SMS|SMIC_RD_END)
271 
272 #define	SMIC_CC_SMM_GET_STATUS	(SMIC_CONTROL|SMIC_SMM|SMIC_GET_STATUS)
273 #define	SMIC_CC_SMM_WR_START	(SMIC_CONTROL|SMIC_SMM|SMIC_WR_START)
274 #define	SMIC_CC_SMM_WR_NEXT	(SMIC_CONTROL|SMIC_SMM|SMIC_WR_NEXT)
275 #define	SMIC_CC_SMM_WR_END	(SMIC_CONTROL|SMIC_SMM|SMIC_WR_END)
276 #define	SMIC_CC_SMM_RD_START	(SMIC_CONTROL|SMIC_SMM|SMIC_RD_START)
277 #define	SMIC_CC_SMM_RD_NEXT	(SMIC_CONTROL|SMIC_SMM|SMIC_RD_NEXT)
278 #define	SMIC_CC_SMM_RD_END	(SMIC_CONTROL|SMIC_SMM|SMIC_RD_END)
279 
280 /*  SMIC Status Codes */
281 #define	SMIC_SC_SMS_READY	(SMIC_STATUS|SMIC_SMS|SMIC_READY)
282 #define	SMIC_SC_SMS_WR_START	(SMIC_STATUS|SMIC_SMS|SMIC_WR_START)
283 #define	SMIC_SC_SMS_WR_NEXT	(SMIC_STATUS|SMIC_SMS|SMIC_WR_NEXT)
284 #define	SMIC_SC_SMS_WR_END	(SMIC_STATUS|SMIC_SMS|SMIC_WR_END)
285 #define	SMIC_SC_SMS_RD_START	(SMIC_STATUS|SMIC_SMS|SMIC_RD_START)
286 #define	SMIC_SC_SMS_RD_NEXT	(SMIC_STATUS|SMIC_SMS|SMIC_RD_NEXT)
287 #define	SMIC_SC_SMS_RD_END	(SMIC_STATUS|SMIC_SMS|SMIC_RD_END)
288 
289 #define	SMIC_SC_SMM_READY	(SMIC_STATUS|SMIC_SMM|SMIC_READY)
290 #define	SMIC_SC_SMM_WR_START	(SMIC_STATUS|SMIC_SMM|SMIC_WR_START)
291 #define	SMIC_SC_SMM_WR_NEXT	(SMIC_STATUS|SMIC_SMM|SMIC_WR_NEXT)
292 #define	SMIC_SC_SMM_WR_END	(SMIC_STATUS|SMIC_SMM|SMIC_WR_END)
293 #define	SMIC_SC_SMM_RD_START	(SMIC_STATUS|SMIC_SMM|SMIC_RD_START)
294 #define	SMIC_SC_SMM_RD_NEXT	(SMIC_STATUS|SMIC_SMM|SMIC_RD_NEXT)
295 #define	SMIC_SC_SMM_RD_END	(SMIC_STATUS|SMIC_SMM|SMIC_RD_END)
296 
297 /* these are the control/status codes we actually use
298 	SMIC_CC_SMS_GET_STATUS	0x40
299 	SMIC_CC_SMS_WR_START	0x41
300 	SMIC_CC_SMS_WR_NEXT	0x42
301 	SMIC_CC_SMS_WR_END	0x43
302 	SMIC_CC_SMS_RD_START	0x44
303 	SMIC_CC_SMS_RD_NEXT	0x45
304 	SMIC_CC_SMS_RD_END	0x46
305 
306 	SMIC_SC_SMS_READY	0xC0
307 	SMIC_SC_SMS_WR_START	0xC1
308 	SMIC_SC_SMS_WR_NEXT	0xC2
309 	SMIC_SC_SMS_WR_END	0xC3
310 	SMIC_SC_SMS_RD_START	0xC4
311 	SMIC_SC_SMS_RD_NEXT	0xC5
312 	SMIC_SC_SMS_RD_END	0xC6
313 */
314 
smic_event(struct si_sm_data * smic,long time)315 static enum si_sm_result smic_event(struct si_sm_data *smic, long time)
316 {
317 	unsigned char status;
318 	unsigned char flags;
319 	unsigned char data;
320 
321 	if (smic->state == SMIC_HOSED) {
322 		init_smic_data(smic, smic->io);
323 		return SI_SM_HOSED;
324 	}
325 	if (smic->state != SMIC_IDLE) {
326 		if (smic_debug & SMIC_DEBUG_STATES)
327 			printk(KERN_DEBUG
328 			       "smic_event - smic->smic_timeout = %ld, time = %ld\n",
329 			       smic->smic_timeout, time);
330 		/*
331 		 * FIXME: smic_event is sometimes called with time >
332 		 * SMIC_RETRY_TIMEOUT
333 		 */
334 		if (time < SMIC_RETRY_TIMEOUT) {
335 			smic->smic_timeout -= time;
336 			if (smic->smic_timeout < 0) {
337 				start_error_recovery(smic, "smic timed out.");
338 				return SI_SM_CALL_WITH_DELAY;
339 			}
340 		}
341 	}
342 	flags = read_smic_flags(smic);
343 	if (flags & SMIC_FLAG_BSY)
344 		return SI_SM_CALL_WITH_DELAY;
345 
346 	status = read_smic_status(smic);
347 	if (smic_debug & SMIC_DEBUG_STATES)
348 		printk(KERN_DEBUG "smic_event - state = %d, flags = 0x%02x, status = 0x%02x\n",
349 		       smic->state, flags, status);
350 
351 	switch (smic->state) {
352 	case SMIC_IDLE:
353 		/* in IDLE we check for available messages */
354 		if (flags & SMIC_SMS_DATA_AVAIL)
355 			return SI_SM_ATTN;
356 		return SI_SM_IDLE;
357 
358 	case SMIC_START_OP:
359 		/* sanity check whether smic is really idle */
360 		write_smic_control(smic, SMIC_CC_SMS_GET_STATUS);
361 		write_smic_flags(smic, flags | SMIC_FLAG_BSY);
362 		smic->state = SMIC_OP_OK;
363 		break;
364 
365 	case SMIC_OP_OK:
366 		if (status != SMIC_SC_SMS_READY) {
367 			/* this should not happen */
368 			start_error_recovery(smic,
369 					     "state = SMIC_OP_OK,"
370 					     " status != SMIC_SC_SMS_READY");
371 			return SI_SM_CALL_WITH_DELAY;
372 		}
373 		/* OK so far; smic is idle let us start ... */
374 		write_smic_control(smic, SMIC_CC_SMS_WR_START);
375 		write_next_byte(smic);
376 		write_smic_flags(smic, flags | SMIC_FLAG_BSY);
377 		smic->state = SMIC_WRITE_START;
378 		break;
379 
380 	case SMIC_WRITE_START:
381 		if (status != SMIC_SC_SMS_WR_START) {
382 			start_error_recovery(smic,
383 					     "state = SMIC_WRITE_START, "
384 					     "status != SMIC_SC_SMS_WR_START");
385 			return SI_SM_CALL_WITH_DELAY;
386 		}
387 		/*
388 		 * we must not issue WR_(NEXT|END) unless
389 		 * TX_DATA_READY is set
390 		 * */
391 		if (flags & SMIC_TX_DATA_READY) {
392 			if (smic->write_count == 1) {
393 				/* last byte */
394 				write_smic_control(smic, SMIC_CC_SMS_WR_END);
395 				smic->state = SMIC_WRITE_END;
396 			} else {
397 				write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
398 				smic->state = SMIC_WRITE_NEXT;
399 			}
400 			write_next_byte(smic);
401 			write_smic_flags(smic, flags | SMIC_FLAG_BSY);
402 		} else
403 			return SI_SM_CALL_WITH_DELAY;
404 		break;
405 
406 	case SMIC_WRITE_NEXT:
407 		if (status != SMIC_SC_SMS_WR_NEXT) {
408 			start_error_recovery(smic,
409 					     "state = SMIC_WRITE_NEXT, "
410 					     "status != SMIC_SC_SMS_WR_NEXT");
411 			return SI_SM_CALL_WITH_DELAY;
412 		}
413 		/* this is the same code as in SMIC_WRITE_START */
414 		if (flags & SMIC_TX_DATA_READY) {
415 			if (smic->write_count == 1) {
416 				write_smic_control(smic, SMIC_CC_SMS_WR_END);
417 				smic->state = SMIC_WRITE_END;
418 			} else {
419 				write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
420 				smic->state = SMIC_WRITE_NEXT;
421 			}
422 			write_next_byte(smic);
423 			write_smic_flags(smic, flags | SMIC_FLAG_BSY);
424 		} else
425 			return SI_SM_CALL_WITH_DELAY;
426 		break;
427 
428 	case SMIC_WRITE_END:
429 		if (status != SMIC_SC_SMS_WR_END) {
430 			start_error_recovery(smic,
431 					     "state = SMIC_WRITE_END, "
432 					     "status != SMIC_SC_SMS_WR_END");
433 			return SI_SM_CALL_WITH_DELAY;
434 		}
435 		/* data register holds an error code */
436 		data = read_smic_data(smic);
437 		if (data != 0) {
438 			if (smic_debug & SMIC_DEBUG_ENABLE)
439 				printk(KERN_DEBUG "SMIC_WRITE_END: data = %02x\n",
440 				       data);
441 			start_error_recovery(smic,
442 					     "state = SMIC_WRITE_END, "
443 					     "data != SUCCESS");
444 			return SI_SM_CALL_WITH_DELAY;
445 		} else
446 			smic->state = SMIC_WRITE2READ;
447 		break;
448 
449 	case SMIC_WRITE2READ:
450 		/*
451 		 * we must wait for RX_DATA_READY to be set before we
452 		 * can continue
453 		 */
454 		if (flags & SMIC_RX_DATA_READY) {
455 			write_smic_control(smic, SMIC_CC_SMS_RD_START);
456 			write_smic_flags(smic, flags | SMIC_FLAG_BSY);
457 			smic->state = SMIC_READ_START;
458 		} else
459 			return SI_SM_CALL_WITH_DELAY;
460 		break;
461 
462 	case SMIC_READ_START:
463 		if (status != SMIC_SC_SMS_RD_START) {
464 			start_error_recovery(smic,
465 					     "state = SMIC_READ_START, "
466 					     "status != SMIC_SC_SMS_RD_START");
467 			return SI_SM_CALL_WITH_DELAY;
468 		}
469 		if (flags & SMIC_RX_DATA_READY) {
470 			read_next_byte(smic);
471 			write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
472 			write_smic_flags(smic, flags | SMIC_FLAG_BSY);
473 			smic->state = SMIC_READ_NEXT;
474 		} else
475 			return SI_SM_CALL_WITH_DELAY;
476 		break;
477 
478 	case SMIC_READ_NEXT:
479 		switch (status) {
480 		/*
481 		 * smic tells us that this is the last byte to be read
482 		 * --> clean up
483 		 */
484 		case SMIC_SC_SMS_RD_END:
485 			read_next_byte(smic);
486 			write_smic_control(smic, SMIC_CC_SMS_RD_END);
487 			write_smic_flags(smic, flags | SMIC_FLAG_BSY);
488 			smic->state = SMIC_READ_END;
489 			break;
490 		case SMIC_SC_SMS_RD_NEXT:
491 			if (flags & SMIC_RX_DATA_READY) {
492 				read_next_byte(smic);
493 				write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
494 				write_smic_flags(smic, flags | SMIC_FLAG_BSY);
495 				smic->state = SMIC_READ_NEXT;
496 			} else
497 				return SI_SM_CALL_WITH_DELAY;
498 			break;
499 		default:
500 			start_error_recovery(
501 				smic,
502 				"state = SMIC_READ_NEXT, "
503 				"status != SMIC_SC_SMS_RD_(NEXT|END)");
504 			return SI_SM_CALL_WITH_DELAY;
505 		}
506 		break;
507 
508 	case SMIC_READ_END:
509 		if (status != SMIC_SC_SMS_READY) {
510 			start_error_recovery(smic,
511 					     "state = SMIC_READ_END, "
512 					     "status != SMIC_SC_SMS_READY");
513 			return SI_SM_CALL_WITH_DELAY;
514 		}
515 		data = read_smic_data(smic);
516 		/* data register holds an error code */
517 		if (data != 0) {
518 			if (smic_debug & SMIC_DEBUG_ENABLE)
519 				printk(KERN_DEBUG "SMIC_READ_END: data = %02x\n",
520 				       data);
521 			start_error_recovery(smic,
522 					     "state = SMIC_READ_END, "
523 					     "data != SUCCESS");
524 			return SI_SM_CALL_WITH_DELAY;
525 		} else {
526 			smic->state = SMIC_IDLE;
527 			return SI_SM_TRANSACTION_COMPLETE;
528 		}
529 
530 	case SMIC_HOSED:
531 		init_smic_data(smic, smic->io);
532 		return SI_SM_HOSED;
533 
534 	default:
535 		if (smic_debug & SMIC_DEBUG_ENABLE) {
536 			printk(KERN_DEBUG "smic->state = %d\n", smic->state);
537 			start_error_recovery(smic, "state = UNKNOWN");
538 			return SI_SM_CALL_WITH_DELAY;
539 		}
540 	}
541 	smic->smic_timeout = SMIC_RETRY_TIMEOUT;
542 	return SI_SM_CALL_WITHOUT_DELAY;
543 }
544 
smic_detect(struct si_sm_data * smic)545 static int smic_detect(struct si_sm_data *smic)
546 {
547 	/*
548 	 * It's impossible for the SMIC fnags register to be all 1's,
549 	 * (assuming a properly functioning, self-initialized BMC)
550 	 * but that's what you get from reading a bogus address, so we
551 	 * test that first.
552 	 */
553 	if (read_smic_flags(smic) == 0xff)
554 		return 1;
555 
556 	return 0;
557 }
558 
smic_cleanup(struct si_sm_data * kcs)559 static void smic_cleanup(struct si_sm_data *kcs)
560 {
561 }
562 
smic_size(void)563 static int smic_size(void)
564 {
565 	return sizeof(struct si_sm_data);
566 }
567 
568 const struct si_sm_handlers smic_smi_handlers = {
569 	.init_data         = init_smic_data,
570 	.start_transaction = start_smic_transaction,
571 	.get_result        = smic_get_result,
572 	.event             = smic_event,
573 	.detect            = smic_detect,
574 	.cleanup           = smic_cleanup,
575 	.size              = smic_size,
576 };
577