char/ipmi/ipmi_kcs_sm.c

125 static unsigned int init_kcs_data_with_state(struct si_sm_data *kcs,
128 	kcs->state = state;
129 	kcs->io = io;
130 	kcs->write_pos = 0;
131 	kcs->write_count = 0;
132 	kcs->orig_write_count = 0;
133 	kcs->read_pos = 0;
134 	kcs->error_retries = 0;
135 	kcs->truncated = 0;
136 	kcs->ibf_timeout = IBF_RETRY_TIMEOUT;
137 	kcs->obf_timeout = OBF_RETRY_TIMEOUT;
143 static unsigned int init_kcs_data(struct si_sm_data *kcs,
146 	return init_kcs_data_with_state(kcs, io, KCS_IDLE);
149 static inline unsigned char read_status(struct si_sm_data *kcs)
151 	return kcs->io->inputb(kcs->io, 1);
154 static inline unsigned char read_data(struct si_sm_data *kcs)
156 	return kcs->io->inputb(kcs->io, 0);
159 static inline void write_cmd(struct si_sm_data *kcs, unsigned char data)
161 	kcs->io->outputb(kcs->io, 1, data);
164 static inline void write_data(struct si_sm_data *kcs, unsigned char data)
166 	kcs->io->outputb(kcs->io, 0, data);
186 static inline void write_next_byte(struct si_sm_data *kcs)
188 	write_data(kcs, kcs->write_data[kcs->write_pos]);
189 	(kcs->write_pos)++;
190 	(kcs->write_count)--;
193 static inline void start_error_recovery(struct si_sm_data *kcs, char *reason)
195 	(kcs->error_retries)++;
196 	if (kcs->error_retries > MAX_ERROR_RETRIES) {
198 			dev_dbg(kcs->io->dev, "ipmi_kcs_sm: kcs hosed: %s\n",
200 		kcs->state = KCS_HOSED;
202 		kcs->error0_timeout = jiffies + ERROR0_OBF_WAIT_JIFFIES;
203 		kcs->state = KCS_ERROR0;
207 static inline void read_next_byte(struct si_sm_data *kcs)
209 	if (kcs->read_pos >= MAX_KCS_READ_SIZE) {
211 		read_data(kcs);
212 		kcs->truncated = 1;
214 		kcs->read_data[kcs->read_pos] = read_data(kcs);
215 		(kcs->read_pos)++;
217 	write_data(kcs, KCS_READ_BYTE);
220 static inline int check_ibf(struct si_sm_data *kcs, unsigned char status,
224 		kcs->ibf_timeout -= time;
225 		if (kcs->ibf_timeout < 0) {
226 			start_error_recovery(kcs, "IBF not ready in time");
227 			kcs->ibf_timeout = IBF_RETRY_TIMEOUT;
232 	kcs->ibf_timeout = IBF_RETRY_TIMEOUT;
236 static inline int check_obf(struct si_sm_data *kcs, unsigned char status,
240 		kcs->obf_timeout -= time;
241 		if (kcs->obf_timeout < 0) {
242 			kcs->obf_timeout = OBF_RETRY_TIMEOUT;
243 			start_error_recovery(kcs, "OBF not ready in time");
248 	kcs->obf_timeout = OBF_RETRY_TIMEOUT;
252 static void clear_obf(struct si_sm_data *kcs, unsigned char status)
255 		read_data(kcs);
258 static void restart_kcs_transaction(struct si_sm_data *kcs)
260 	kcs->write_count = kcs->orig_write_count;
261 	kcs->write_pos = 0;
262 	kcs->read_pos = 0;
263 	kcs->state = KCS_WAIT_WRITE_START;
264 	kcs->ibf_timeout = IBF_RETRY_TIMEOUT;
265 	kcs->obf_timeout = OBF_RETRY_TIMEOUT;
266 	write_cmd(kcs, KCS_WRITE_START);
269 static int start_kcs_transaction(struct si_sm_data *kcs, unsigned char *data,
279 	if (kcs->state != KCS_IDLE) {
280 		dev_warn(kcs->io->dev, "KCS in invalid state %d\n", kcs->state);
285 		dev_dbg(kcs->io->dev, "%s -", __func__);
290 	kcs->error_retries = 0;
291 	memcpy(kcs->write_data, data, size);
292 	kcs->write_count = size;
293 	kcs->orig_write_count = size;
294 	kcs->write_pos = 0;
295 	kcs->read_pos = 0;
296 	kcs->state = KCS_START_OP;
297 	kcs->ibf_timeout = IBF_RETRY_TIMEOUT;
298 	kcs->obf_timeout = OBF_RETRY_TIMEOUT;
302 static int get_kcs_result(struct si_sm_data *kcs, unsigned char *data,
305 	if (length < kcs->read_pos) {
306 		kcs->read_pos = length;
307 		kcs->truncated = 1;
310 	memcpy(data, kcs->read_data, kcs->read_pos);
312 	if ((length >= 3) && (kcs->read_pos < 3)) {
316 		kcs->read_pos = 3;
318 	if (kcs->truncated) {
325 		kcs->truncated = 0;
328 	return kcs->read_pos;
336 static enum si_sm_result kcs_event(struct si_sm_data *kcs, long time)
341 	status = read_status(kcs);
344 		dev_dbg(kcs->io->dev,
345 			"KCS: State = %d, %x\n", kcs->state, status);
348 	if (!check_ibf(kcs, status, time))
354 	switch (kcs->state) {
357 		clear_obf(kcs, status);
366 			start_error_recovery(kcs,
371 		clear_obf(kcs, status);
372 		write_cmd(kcs, KCS_WRITE_START);
373 		kcs->state = KCS_WAIT_WRITE_START;
379 				kcs,
383 		read_data(kcs);
384 		if (kcs->write_count == 1) {
385 			write_cmd(kcs, KCS_WRITE_END);
386 			kcs->state = KCS_WAIT_WRITE_END;
388 			write_next_byte(kcs);
389 			kcs->state = KCS_WAIT_WRITE;
395 			start_error_recovery(kcs,
399 		clear_obf(kcs, status);
400 		if (kcs->write_count == 1) {
401 			write_cmd(kcs, KCS_WRITE_END);
402 			kcs->state = KCS_WAIT_WRITE_END;
404 			write_next_byte(kcs);
410 			start_error_recovery(kcs,
415 		clear_obf(kcs, status);
416 		write_next_byte(kcs);
417 		kcs->state = KCS_WAIT_READ;
423 				kcs,
429 			if (!check_obf(kcs, status, time))
431 			read_next_byte(kcs);
442 			clear_obf(kcs, status);
443 			kcs->orig_write_count = 0;
444 			kcs->state = KCS_IDLE;
450 		clear_obf(kcs, status);
451 		status = read_status(kcs);
454 			if (time_before(jiffies, kcs->error0_timeout))
456 		write_cmd(kcs, KCS_GET_STATUS_ABORT);
457 		kcs->state = KCS_ERROR1;
461 		clear_obf(kcs, status);
462 		write_data(kcs, 0);
463 		kcs->state = KCS_ERROR2;
468 			start_error_recovery(kcs,
472 		if (!check_obf(kcs, status, time))
475 		clear_obf(kcs, status);
476 		write_data(kcs, KCS_READ_BYTE);
477 		kcs->state = KCS_ERROR3;
482 			start_error_recovery(kcs,
487 		if (!check_obf(kcs, status, time))
490 		clear_obf(kcs, status);
491 		if (kcs->orig_write_count) {
492 			restart_kcs_transaction(kcs);
494 			kcs->state = KCS_IDLE;
503 	if (kcs->state == KCS_HOSED) {
504 		init_kcs_data_with_state(kcs, kcs->io, KCS_ERROR0);
516 static int kcs_detect(struct si_sm_data *kcs)
524 	if (read_status(kcs) == 0xff)
530 static void kcs_cleanup(struct si_sm_data *kcs)