fsi-occ.c

  1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <linux/device.h>
  4#include <linux/err.h>
  5#include <linux/errno.h>
  6#include <linux/fs.h>
  7#include <linux/fsi-sbefifo.h>
  8#include <linux/gfp.h>
  9#include <linux/idr.h>
 10#include <linux/kernel.h>
 11#include <linux/list.h>
 12#include <linux/miscdevice.h>
 13#include <linux/mm.h>
 14#include <linux/module.h>
 15#include <linux/mutex.h>
 16#include <linux/fsi-occ.h>
 17#include <linux/of.h>
 18#include <linux/of_platform.h>
 19#include <linux/platform_device.h>
 20#include <linux/sched.h>
 21#include <linux/slab.h>
 22#include <linux/uaccess.h>
 23#include <linux/unaligned.h>
 24
 25#define OCC_SRAM_BYTES		8192
 26#define OCC_CMD_DATA_BYTES	8186
 27#define OCC_RESP_DATA_BYTES	8185
 28
 29#define OCC_P9_SRAM_CMD_ADDR	0xFFFBE000
 30#define OCC_P9_SRAM_RSP_ADDR	0xFFFBF000
 31
 32#define OCC_P10_SRAM_CMD_ADDR	0xFFFFD000
 33#define OCC_P10_SRAM_RSP_ADDR	0xFFFFE000
 34
 35#define OCC_P10_SRAM_MODE	0x58	/* Normal mode, OCB channel 2 */
 36
 37#define OCC_TIMEOUT_MS		1000
 38#define OCC_CMD_IN_PRG_WAIT_MS	50
 39
 40enum versions { occ_p9, occ_p10 };
 41
 42struct occ {
 43	struct device *dev;
 44	struct device *sbefifo;
 45	char name[32];
 46	int idx;
 47	bool platform_hwmon;
 48	u8 sequence_number;
 49	void *buffer;
 50	void *client_buffer;
 51	size_t client_buffer_size;
 52	size_t client_response_size;
 53	enum versions version;
 54	struct miscdevice mdev;
 55	struct mutex occ_lock;
 56};
 57
 58#define to_occ(x)	container_of((x), struct occ, mdev)
 59
 60struct occ_response {
 61	u8 seq_no;
 62	u8 cmd_type;
 63	u8 return_status;
 64	__be16 data_length;
 65	u8 data[OCC_RESP_DATA_BYTES + 2];	/* two bytes checksum */
 66} __packed;
 67
 68struct occ_client {
 69	struct occ *occ;
 70	struct mutex lock;
 71	size_t data_size;
 72	size_t read_offset;
 73	u8 *buffer;
 74};
 75
 76#define to_client(x)	container_of((x), struct occ_client, xfr)
 77
 78static DEFINE_IDA(occ_ida);
 79
 80static int occ_open(struct inode *inode, struct file *file)
 81{
 82	struct occ_client *client = kzalloc(sizeof(*client), GFP_KERNEL);
 83	struct miscdevice *mdev = file->private_data;
 84	struct occ *occ = to_occ(mdev);
 85
 86	if (!client)
 87		return -ENOMEM;
 88
 89	client->buffer = kvmalloc(OCC_SRAM_BYTES, GFP_KERNEL);
 90	if (!client->buffer) {
 91		kfree(client);
 92		return -ENOMEM;
 93	}
 94
 95	client->occ = occ;
 96	mutex_init(&client->lock);
 97	file->private_data = client;
 98	get_device(occ->dev);
 99
100	return 0;
101}
102
103static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
104			loff_t *offset)
105{
106	struct occ_client *client = file->private_data;
107	ssize_t rc = 0;
108
109	if (!client)
110		return -ENODEV;
111
112	if (len > OCC_SRAM_BYTES)
113		return -EINVAL;
114
115	mutex_lock(&client->lock);
116
117	/* This should not be possible ... */
118	if (WARN_ON_ONCE(client->read_offset > client->data_size)) {
119		rc = -EIO;
120		goto done;
121	}
122
123	/* Grab how much data we have to read */
124	rc = min(len, client->data_size - client->read_offset);
125	if (copy_to_user(buf, client->buffer + client->read_offset, rc))
126		rc = -EFAULT;
127	else
128		client->read_offset += rc;
129
130 done:
131	mutex_unlock(&client->lock);
132
133	return rc;
134}
135
136static ssize_t occ_write(struct file *file, const char __user *buf,
137			 size_t len, loff_t *offset)
138{
139	struct occ_client *client = file->private_data;
140	size_t rlen, data_length;
141	ssize_t rc;
142	u8 *cmd;
143
144	if (!client)
145		return -ENODEV;
146
147	if (len > (OCC_CMD_DATA_BYTES + 3) || len < 3)
148		return -EINVAL;
149
150	mutex_lock(&client->lock);
151
152	/* Construct the command */
153	cmd = client->buffer;
154
155	/*
156	 * Copy the user command (assume user data follows the occ command
157	 * format)
158	 * byte 0: command type
159	 * bytes 1-2: data length (msb first)
160	 * bytes 3-n: data
161	 */
162	if (copy_from_user(&cmd[1], buf, len)) {
163		rc = -EFAULT;
164		goto done;
165	}
166
167	/* Extract data length */
168	data_length = (cmd[2] << 8) + cmd[3];
169	if (data_length > OCC_CMD_DATA_BYTES) {
170		rc = -EINVAL;
171		goto done;
172	}
173
174	/* Submit command; 4 bytes before the data and 2 bytes after */
175	rlen = OCC_SRAM_BYTES;
176	rc = fsi_occ_submit(client->occ->dev, cmd, data_length + 6, cmd,
177			    &rlen);
178	if (rc)
179		goto done;
180
181	/* Set read tracking data */
182	client->data_size = rlen;
183	client->read_offset = 0;
184
185	/* Done */
186	rc = len;
187
188 done:
189	mutex_unlock(&client->lock);
190
191	return rc;
192}
193
194static int occ_release(struct inode *inode, struct file *file)
195{
196	struct occ_client *client = file->private_data;
197
198	put_device(client->occ->dev);
199	kvfree(client->buffer);
200	kfree(client);
201
202	return 0;
203}
204
205static const struct file_operations occ_fops = {
206	.owner = THIS_MODULE,
207	.open = occ_open,
208	.read = occ_read,
209	.write = occ_write,
210	.release = occ_release,
211};
212
213static void occ_save_ffdc(struct occ *occ, __be32 *resp, size_t parsed_len,
214			  size_t resp_len)
215{
216	if (resp_len > parsed_len) {
217		size_t dh = resp_len - parsed_len;
218		size_t ffdc_len = (dh - 1) * 4; /* SBE words are four bytes */
219		__be32 *ffdc = &resp[parsed_len];
220
221		if (ffdc_len > occ->client_buffer_size)
222			ffdc_len = occ->client_buffer_size;
223
224		memcpy(occ->client_buffer, ffdc, ffdc_len);
225		occ->client_response_size = ffdc_len;
226	}
227}
228
229static int occ_verify_checksum(struct occ *occ, struct occ_response *resp,
230			       u16 data_length)
231{
232	/* Fetch the two bytes after the data for the checksum. */
233	u16 checksum_resp = get_unaligned_be16(&resp->data[data_length]);
234	u16 checksum;
235	u16 i;
236
237	checksum = resp->seq_no;
238	checksum += resp->cmd_type;
239	checksum += resp->return_status;
240	checksum += (data_length >> 8) + (data_length & 0xFF);
241
242	for (i = 0; i < data_length; ++i)
243		checksum += resp->data[i];
244
245	if (checksum != checksum_resp) {
246		dev_err(occ->dev, "Bad checksum: %04x!=%04x\n", checksum,
247			checksum_resp);
248		return -EBADE;
249	}
250
251	return 0;
252}
253
254static int occ_getsram(struct occ *occ, u32 offset, void *data, ssize_t len)
255{
256	u32 data_len = ((len + 7) / 8) * 8;	/* must be multiples of 8 B */
257	size_t cmd_len, parsed_len, resp_data_len;
258	size_t resp_len = OCC_MAX_RESP_WORDS;
259	__be32 *resp = occ->buffer;
260	__be32 cmd[6];
261	int idx = 0, rc;
262
263	/*
264	 * Magic sequence to do SBE getsram command. SBE will fetch data from
265	 * specified SRAM address.
266	 */
267	switch (occ->version) {
268	default:
269	case occ_p9:
270		cmd_len = 5;
271		cmd[2] = cpu_to_be32(1);	/* Normal mode */
272		cmd[3] = cpu_to_be32(OCC_P9_SRAM_RSP_ADDR + offset);
273		break;
274	case occ_p10:
275		idx = 1;
276		cmd_len = 6;
277		cmd[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
278		cmd[3] = 0;
279		cmd[4] = cpu_to_be32(OCC_P10_SRAM_RSP_ADDR + offset);
280		break;
281	}
282
283	cmd[0] = cpu_to_be32(cmd_len);
284	cmd[1] = cpu_to_be32(SBEFIFO_CMD_GET_OCC_SRAM);
285	cmd[4 + idx] = cpu_to_be32(data_len);
286
287	rc = sbefifo_submit(occ->sbefifo, cmd, cmd_len, resp, &resp_len);
288	if (rc)
289		return rc;
290
291	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_GET_OCC_SRAM,
292				  resp, resp_len, &parsed_len);
293	if (rc > 0) {
294		dev_err(occ->dev, "SRAM read returned failure status: %08x\n",
295			rc);
296		occ_save_ffdc(occ, resp, parsed_len, resp_len);
297		return -ECOMM;
298	} else if (rc) {
299		return rc;
300	}
301
302	resp_data_len = be32_to_cpu(resp[parsed_len - 1]);
303	if (resp_data_len != data_len) {
304		dev_err(occ->dev, "SRAM read expected %d bytes got %zd\n",
305			data_len, resp_data_len);
306		rc = -EBADMSG;
307	} else {
308		memcpy(data, resp, len);
309	}
310
311	return rc;
312}
313
314static int occ_putsram(struct occ *occ, const void *data, ssize_t len,
315		       u8 seq_no, u16 checksum)
316{
317	u32 data_len = ((len + 7) / 8) * 8;	/* must be multiples of 8 B */
318	size_t cmd_len, parsed_len, resp_data_len;
319	size_t resp_len = OCC_MAX_RESP_WORDS;
320	__be32 *buf = occ->buffer;
321	u8 *byte_buf;
322	int idx = 0, rc;
323
324	cmd_len = (occ->version == occ_p10) ? 6 : 5;
325	cmd_len += data_len >> 2;
326
327	/*
328	 * Magic sequence to do SBE putsram command. SBE will transfer
329	 * data to specified SRAM address.
330	 */
331	buf[0] = cpu_to_be32(cmd_len);
332	buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
333
334	switch (occ->version) {
335	default:
336	case occ_p9:
337		buf[2] = cpu_to_be32(1);	/* Normal mode */
338		buf[3] = cpu_to_be32(OCC_P9_SRAM_CMD_ADDR);
339		break;
340	case occ_p10:
341		idx = 1;
342		buf[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
343		buf[3] = 0;
344		buf[4] = cpu_to_be32(OCC_P10_SRAM_CMD_ADDR);
345		break;
346	}
347
348	buf[4 + idx] = cpu_to_be32(data_len);
349	memcpy(&buf[5 + idx], data, len);
350
351	byte_buf = (u8 *)&buf[5 + idx];
352	/*
353	 * Overwrite the first byte with our sequence number and the last two
354	 * bytes with the checksum.
355	 */
356	byte_buf[0] = seq_no;
357	byte_buf[len - 2] = checksum >> 8;
358	byte_buf[len - 1] = checksum & 0xff;
359
360	rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
361	if (rc)
362		return rc;
363
364	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
365				  buf, resp_len, &parsed_len);
366	if (rc > 0) {
367		dev_err(occ->dev, "SRAM write returned failure status: %08x\n",
368			rc);
369		occ_save_ffdc(occ, buf, parsed_len, resp_len);
370		return -ECOMM;
371	} else if (rc) {
372		return rc;
373	}
374
375	if (parsed_len != 1) {
376		dev_err(occ->dev, "SRAM write response length invalid: %zd\n",
377			parsed_len);
378		rc = -EBADMSG;
379	} else {
380		resp_data_len = be32_to_cpu(buf[0]);
381		if (resp_data_len != data_len) {
382			dev_err(occ->dev,
383				"SRAM write expected %d bytes got %zd\n",
384				data_len, resp_data_len);
385			rc = -EBADMSG;
386		}
387	}
388
389	return rc;
390}
391
392static int occ_trigger_attn(struct occ *occ)
393{
394	__be32 *buf = occ->buffer;
395	size_t cmd_len, parsed_len, resp_data_len;
396	size_t resp_len = OCC_MAX_RESP_WORDS;
397	int idx = 0, rc;
398
399	switch (occ->version) {
400	default:
401	case occ_p9:
402		cmd_len = 7;
403		buf[2] = cpu_to_be32(3); /* Circular mode */
404		buf[3] = 0;
405		break;
406	case occ_p10:
407		idx = 1;
408		cmd_len = 8;
409		buf[2] = cpu_to_be32(0xd0); /* Circular mode, OCB Channel 1 */
410		buf[3] = 0;
411		buf[4] = 0;
412		break;
413	}
414
415	buf[0] = cpu_to_be32(cmd_len);		/* Chip-op length in words */
416	buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
417	buf[4 + idx] = cpu_to_be32(8);		/* Data length in bytes */
418	buf[5 + idx] = cpu_to_be32(0x20010000);	/* Trigger OCC attention */
419	buf[6 + idx] = 0;
420
421	rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
422	if (rc)
423		return rc;
424
425	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
426				  buf, resp_len, &parsed_len);
427	if (rc > 0) {
428		dev_err(occ->dev, "SRAM attn returned failure status: %08x\n",
429			rc);
430		occ_save_ffdc(occ, buf, parsed_len, resp_len);
431		return -ECOMM;
432	} else if (rc) {
433		return rc;
434	}
435
436	if (parsed_len != 1) {
437		dev_err(occ->dev, "SRAM attn response length invalid: %zd\n",
438			parsed_len);
439		rc = -EBADMSG;
440	} else {
441		resp_data_len = be32_to_cpu(buf[0]);
442		if (resp_data_len != 8) {
443			dev_err(occ->dev,
444				"SRAM attn expected 8 bytes got %zd\n",
445				resp_data_len);
446			rc = -EBADMSG;
447		}
448	}
449
450	return rc;
451}
452
453static bool fsi_occ_response_not_ready(struct occ_response *resp, u8 seq_no,
454				       u8 cmd_type)
455{
456	return resp->return_status == OCC_RESP_CMD_IN_PRG ||
457		resp->return_status == OCC_RESP_CRIT_INIT ||
458		resp->seq_no != seq_no || resp->cmd_type != cmd_type;
459}
460
461int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
462		   void *response, size_t *resp_len)
463{
464	const unsigned long timeout = msecs_to_jiffies(OCC_TIMEOUT_MS);
465	const unsigned long wait_time =
466		msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
467	struct occ *occ = dev_get_drvdata(dev);
468	struct occ_response *resp = response;
469	size_t user_resp_len = *resp_len;
470	u8 seq_no;
471	u8 cmd_type;
472	u16 checksum = 0;
473	u16 resp_data_length;
474	const u8 *byte_request = (const u8 *)request;
475	unsigned long end;
476	int rc;
477	size_t i;
478
479	*resp_len = 0;
480
481	if (!occ)
482		return -ENODEV;
483
484	if (user_resp_len < 7) {
485		dev_dbg(dev, "Bad resplen %zd\n", user_resp_len);
486		return -EINVAL;
487	}
488
489	cmd_type = byte_request[1];
490
491	/* Checksum the request, ignoring first byte (sequence number). */
492	for (i = 1; i < req_len - 2; ++i)
493		checksum += byte_request[i];
494
495	rc = mutex_lock_interruptible(&occ->occ_lock);
496	if (rc)
497		return rc;
498
499	occ->client_buffer = response;
500	occ->client_buffer_size = user_resp_len;
501	occ->client_response_size = 0;
502
503	if (!occ->buffer) {
504		rc = -ENOENT;
505		goto done;
506	}
507
508	/*
509	 * Get a sequence number and update the counter. Avoid a sequence
510	 * number of 0 which would pass the response check below even if the
511	 * OCC response is uninitialized. Any sequence number the user is
512	 * trying to send is overwritten since this function is the only common
513	 * interface to the OCC and therefore the only place we can guarantee
514	 * unique sequence numbers.
515	 */
516	seq_no = occ->sequence_number++;
517	if (!occ->sequence_number)
518		occ->sequence_number = 1;
519	checksum += seq_no;
520
521	rc = occ_putsram(occ, request, req_len, seq_no, checksum);
522	if (rc)
523		goto done;
524
525	rc = occ_trigger_attn(occ);
526	if (rc)
527		goto done;
528
529	end = jiffies + timeout;
530	while (true) {
531		/* Read occ response header */
532		rc = occ_getsram(occ, 0, resp, 8);
533		if (rc)
534			goto done;
535
536		if (fsi_occ_response_not_ready(resp, seq_no, cmd_type)) {
537			if (time_after(jiffies, end)) {
538				dev_err(occ->dev,
539					"resp timeout status=%02x seq=%d cmd=%d, our seq=%d cmd=%d\n",
540					resp->return_status, resp->seq_no,
541					resp->cmd_type, seq_no, cmd_type);
542				rc = -ETIMEDOUT;
543				goto done;
544			}
545
546			set_current_state(TASK_UNINTERRUPTIBLE);
547			schedule_timeout(wait_time);
548		} else {
549			/* Extract size of response data */
550			resp_data_length =
551				get_unaligned_be16(&resp->data_length);
552
553			/*
554			 * Message size is data length + 5 bytes header + 2
555			 * bytes checksum
556			 */
557			if ((resp_data_length + 7) > user_resp_len) {
558				rc = -EMSGSIZE;
559				goto done;
560			}
561
562			/*
563			 * Get the entire response including the header again,
564			 * in case it changed
565			 */
566			if (resp_data_length > 1) {
567				rc = occ_getsram(occ, 0, resp,
568						 resp_data_length + 7);
569				if (rc)
570					goto done;
571
572				if (!fsi_occ_response_not_ready(resp, seq_no,
573								cmd_type))
574					break;
575			} else {
576				break;
577			}
578		}
579	}
580
581	dev_dbg(dev, "resp_status=%02x resp_data_len=%d\n",
582		resp->return_status, resp_data_length);
583
584	rc = occ_verify_checksum(occ, resp, resp_data_length);
585	if (rc)
586		goto done;
587
588	occ->client_response_size = resp_data_length + 7;
589
590 done:
591	*resp_len = occ->client_response_size;
592	mutex_unlock(&occ->occ_lock);
593
594	return rc;
595}
596EXPORT_SYMBOL_GPL(fsi_occ_submit);
597
598static int occ_unregister_platform_child(struct device *dev, void *data)
599{
600	struct platform_device *hwmon_dev = to_platform_device(dev);
601
602	platform_device_unregister(hwmon_dev);
603
604	return 0;
605}
606
607static int occ_unregister_of_child(struct device *dev, void *data)
608{
609	struct platform_device *hwmon_dev = to_platform_device(dev);
610
611	of_device_unregister(hwmon_dev);
612	if (dev->of_node)
613		of_node_clear_flag(dev->of_node, OF_POPULATED);
614
615	return 0;
616}
617
618static int occ_probe(struct platform_device *pdev)
619{
620	int rc;
621	u32 reg;
622	char child_name[32];
623	struct occ *occ;
624	struct platform_device *hwmon_dev = NULL;
625	struct device_node *hwmon_node;
626	struct device *dev = &pdev->dev;
627	struct platform_device_info hwmon_dev_info = {
628		.parent = dev,
629		.name = "occ-hwmon",
630	};
631
632	occ = devm_kzalloc(dev, sizeof(*occ), GFP_KERNEL);
633	if (!occ)
634		return -ENOMEM;
635
636	/* SBE words are always four bytes */
637	occ->buffer = kvmalloc(OCC_MAX_RESP_WORDS * 4, GFP_KERNEL);
638	if (!occ->buffer)
639		return -ENOMEM;
640
641	occ->version = (uintptr_t)of_device_get_match_data(dev);
642	occ->dev = dev;
643	occ->sbefifo = dev->parent;
644	/*
645	 * Quickly derive a pseudo-random number from jiffies so that
646	 * re-probing the driver doesn't accidentally overlap sequence numbers.
647	 */
648	occ->sequence_number = (u8)((jiffies % 0xff) + 1);
649	mutex_init(&occ->occ_lock);
650
651	if (dev->of_node) {
652		rc = of_property_read_u32(dev->of_node, "reg", &reg);
653		if (!rc) {
654			/* make sure we don't have a duplicate from dts */
655			occ->idx = ida_alloc_range(&occ_ida, reg, reg,
656						   GFP_KERNEL);
657			if (occ->idx < 0)
658				occ->idx = ida_alloc_min(&occ_ida, 1,
659							 GFP_KERNEL);
660		} else {
661			occ->idx = ida_alloc_min(&occ_ida, 1, GFP_KERNEL);
662		}
663	} else {
664		occ->idx = ida_alloc_min(&occ_ida, 1, GFP_KERNEL);
665	}
666
667	platform_set_drvdata(pdev, occ);
668
669	snprintf(occ->name, sizeof(occ->name), "occ%d", occ->idx);
670	occ->mdev.fops = &occ_fops;
671	occ->mdev.minor = MISC_DYNAMIC_MINOR;
672	occ->mdev.name = occ->name;
673	occ->mdev.parent = dev;
674
675	rc = misc_register(&occ->mdev);
676	if (rc) {
677		dev_err(dev, "failed to register miscdevice: %d\n", rc);
678		ida_free(&occ_ida, occ->idx);
679		kvfree(occ->buffer);
680		return rc;
681	}
682
683	hwmon_node = of_get_child_by_name(dev->of_node, hwmon_dev_info.name);
684	if (hwmon_node) {
685		snprintf(child_name, sizeof(child_name), "%s.%d", hwmon_dev_info.name, occ->idx);
686		hwmon_dev = of_platform_device_create(hwmon_node, child_name, dev);
687		of_node_put(hwmon_node);
688	}
689
690	if (!hwmon_dev) {
691		occ->platform_hwmon = true;
692		hwmon_dev_info.id = occ->idx;
693		hwmon_dev = platform_device_register_full(&hwmon_dev_info);
694		if (IS_ERR(hwmon_dev))
695			dev_warn(dev, "failed to create hwmon device\n");
696	}
697
698	return 0;
699}
700
701static void occ_remove(struct platform_device *pdev)
702{
703	struct occ *occ = platform_get_drvdata(pdev);
704
705	misc_deregister(&occ->mdev);
706
707	mutex_lock(&occ->occ_lock);
708	kvfree(occ->buffer);
709	occ->buffer = NULL;
710	mutex_unlock(&occ->occ_lock);
711
712	if (occ->platform_hwmon)
713		device_for_each_child(&pdev->dev, NULL, occ_unregister_platform_child);
714	else
715		device_for_each_child(&pdev->dev, NULL, occ_unregister_of_child);
716
717	ida_free(&occ_ida, occ->idx);
718}
719
720static const struct of_device_id occ_match[] = {
721	{
722		.compatible = "ibm,p9-occ",
723		.data = (void *)occ_p9
724	},
725	{
726		.compatible = "ibm,p10-occ",
727		.data = (void *)occ_p10
728	},
729	{ },
730};
731MODULE_DEVICE_TABLE(of, occ_match);
732
733static struct platform_driver occ_driver = {
734	.driver = {
735		.name = "occ",
736		.of_match_table	= occ_match,
737	},
738	.probe	= occ_probe,
739	.remove = occ_remove,
740};
741
742static int occ_init(void)
743{
744	return platform_driver_register(&occ_driver);
745}
746
747static void occ_exit(void)
748{
749	platform_driver_unregister(&occ_driver);
750
751	ida_destroy(&occ_ida);
752}
753
754module_init(occ_init);
755module_exit(occ_exit);
756
757MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
758MODULE_DESCRIPTION("BMC P9 OCC driver");
759MODULE_LICENSE("GPL");