1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Intel On Demand (Software Defined Silicon) driver
4  *
5  * Copyright (c) 2022, Intel Corporation.
6  * All Rights Reserved.
7  *
8  * Author: "David E. Box" <david.e.box@linux.intel.com>
9  */
10 
11 #include <linux/auxiliary_bus.h>
12 #include <linux/bits.h>
13 #include <linux/bitfield.h>
14 #include <linux/device.h>
15 #include <linux/intel_vsec.h>
16 #include <linux/iopoll.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/overflow.h>
20 #include <linux/pci.h>
21 #include <linux/slab.h>
22 #include <linux/sysfs.h>
23 #include <linux/types.h>
24 #include <linux/uaccess.h>
25 
26 #define ACCESS_TYPE_BARID		2
27 #define ACCESS_TYPE_LOCAL		3
28 
29 #define SDSI_MIN_SIZE_DWORDS		276
30 #define SDSI_SIZE_MAILBOX		1024
31 #define SDSI_SIZE_REGS			80
32 #define SDSI_SIZE_CMD			sizeof(u64)
33 
34 /*
35  * Write messages are currently up to the size of the mailbox
36  * while read messages are up to 4 times the size of the
37  * mailbox, sent in packets
38  */
39 #define SDSI_SIZE_WRITE_MSG		SDSI_SIZE_MAILBOX
40 #define SDSI_SIZE_READ_MSG		(SDSI_SIZE_MAILBOX * 4)
41 
42 #define SDSI_ENABLED_FEATURES_OFFSET	16
43 #define SDSI_FEATURE_SDSI		BIT(3)
44 #define SDSI_FEATURE_METERING		BIT(26)
45 
46 #define SDSI_SOCKET_ID_OFFSET		64
47 #define SDSI_SOCKET_ID			GENMASK(3, 0)
48 
49 #define SDSI_MBOX_CMD_SUCCESS		0x40
50 #define SDSI_MBOX_CMD_TIMEOUT		0x80
51 
52 #define MBOX_TIMEOUT_US			500000
53 #define MBOX_TIMEOUT_ACQUIRE_US		1000
54 #define MBOX_POLLING_PERIOD_US		100
55 #define MBOX_ACQUIRE_NUM_RETRIES	5
56 #define MBOX_ACQUIRE_RETRY_DELAY_MS	500
57 #define MBOX_MAX_PACKETS		4
58 
59 #define MBOX_OWNER_NONE			0x00
60 #define MBOX_OWNER_INBAND		0x01
61 
62 #define CTRL_RUN_BUSY			BIT(0)
63 #define CTRL_READ_WRITE			BIT(1)
64 #define CTRL_SOM			BIT(2)
65 #define CTRL_EOM			BIT(3)
66 #define CTRL_OWNER			GENMASK(5, 4)
67 #define CTRL_COMPLETE			BIT(6)
68 #define CTRL_READY			BIT(7)
69 #define CTRL_INBAND_LOCK		BIT(32)
70 #define CTRL_METER_ENABLE_DRAM		BIT(33)
71 #define CTRL_STATUS			GENMASK(15, 8)
72 #define CTRL_PACKET_SIZE		GENMASK(31, 16)
73 #define CTRL_MSG_SIZE			GENMASK(63, 48)
74 
75 #define DISC_TABLE_SIZE			12
76 #define DT_ACCESS_TYPE			GENMASK(3, 0)
77 #define DT_SIZE				GENMASK(27, 12)
78 #define DT_TBIR				GENMASK(2, 0)
79 #define DT_OFFSET(v)			((v) & GENMASK(31, 3))
80 
81 #define SDSI_GUID_V1			0x006DD191
82 #define GUID_V1_CNTRL_SIZE		8
83 #define GUID_V1_REGS_SIZE		72
84 #define SDSI_GUID_V2			0xF210D9EF
85 #define GUID_V2_CNTRL_SIZE		16
86 #define GUID_V2_REGS_SIZE		80
87 
88 enum sdsi_command {
89 	SDSI_CMD_PROVISION_AKC		= 0x0004,
90 	SDSI_CMD_PROVISION_CAP		= 0x0008,
91 	SDSI_CMD_READ_STATE		= 0x0010,
92 	SDSI_CMD_READ_METER		= 0x0014,
93 };
94 
95 struct sdsi_mbox_info {
96 	u64	*payload;
97 	void	*buffer;
98 	u64	control_flags;
99 	int	size;
100 };
101 
102 struct disc_table {
103 	u32	access_info;
104 	u32	guid;
105 	u32	offset;
106 };
107 
108 struct sdsi_priv {
109 	struct mutex		mb_lock;	/* Mailbox access lock */
110 	struct device		*dev;
111 	void __iomem		*control_addr;
112 	void __iomem		*mbox_addr;
113 	void __iomem		*regs_addr;
114 	int			control_size;
115 	int			maibox_size;
116 	int			registers_size;
117 	u32			guid;
118 	u32			features;
119 };
120 
121 /* SDSi mailbox operations must be performed using 64bit mov instructions */
122 static __always_inline void
sdsi_memcpy64_toio(u64 __iomem * to,const u64 * from,size_t count_bytes)123 sdsi_memcpy64_toio(u64 __iomem *to, const u64 *from, size_t count_bytes)
124 {
125 	size_t count = count_bytes / sizeof(*to);
126 	int i;
127 
128 	for (i = 0; i < count; i++)
129 		writeq(from[i], &to[i]);
130 }
131 
132 static __always_inline void
sdsi_memcpy64_fromio(u64 * to,const u64 __iomem * from,size_t count_bytes)133 sdsi_memcpy64_fromio(u64 *to, const u64 __iomem *from, size_t count_bytes)
134 {
135 	size_t count = count_bytes / sizeof(*to);
136 	int i;
137 
138 	for (i = 0; i < count; i++)
139 		to[i] = readq(&from[i]);
140 }
141 
sdsi_complete_transaction(struct sdsi_priv * priv)142 static inline void sdsi_complete_transaction(struct sdsi_priv *priv)
143 {
144 	u64 control = FIELD_PREP(CTRL_COMPLETE, 1);
145 
146 	lockdep_assert_held(&priv->mb_lock);
147 	writeq(control, priv->control_addr);
148 }
149 
sdsi_status_to_errno(u32 status)150 static int sdsi_status_to_errno(u32 status)
151 {
152 	switch (status) {
153 	case SDSI_MBOX_CMD_SUCCESS:
154 		return 0;
155 	case SDSI_MBOX_CMD_TIMEOUT:
156 		return -ETIMEDOUT;
157 	default:
158 		return -EIO;
159 	}
160 }
161 
sdsi_mbox_poll(struct sdsi_priv * priv,struct sdsi_mbox_info * info,size_t * data_size)162 static int sdsi_mbox_poll(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
163 			  size_t *data_size)
164 {
165 	struct device *dev = priv->dev;
166 	u32 total, loop, eom, status, message_size;
167 	u64 control;
168 	int ret;
169 
170 	lockdep_assert_held(&priv->mb_lock);
171 
172 	/* For reads, data sizes that are larger than the mailbox size are read in packets. */
173 	total = 0;
174 	loop = 0;
175 	do {
176 		u32 packet_size;
177 
178 		/* Poll on ready bit */
179 		ret = readq_poll_timeout(priv->control_addr, control, control & CTRL_READY,
180 					 MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_US);
181 		if (ret)
182 			break;
183 
184 		eom = FIELD_GET(CTRL_EOM, control);
185 		status = FIELD_GET(CTRL_STATUS, control);
186 		packet_size = FIELD_GET(CTRL_PACKET_SIZE, control);
187 		message_size = FIELD_GET(CTRL_MSG_SIZE, control);
188 
189 		ret = sdsi_status_to_errno(status);
190 		if (ret)
191 			break;
192 
193 		if (!packet_size) {
194 			sdsi_complete_transaction(priv);
195 			break;
196 		}
197 
198 		/* Only the last packet can be less than the mailbox size. */
199 		if (!eom && packet_size != SDSI_SIZE_MAILBOX) {
200 			dev_err(dev, "Invalid packet size\n");
201 			ret = -EPROTO;
202 			break;
203 		}
204 
205 		if (packet_size > SDSI_SIZE_MAILBOX) {
206 			dev_err(dev, "Packet size too large\n");
207 			ret = -EPROTO;
208 			break;
209 		}
210 
211 		if (info->buffer) {
212 			void *buf = info->buffer + array_size(SDSI_SIZE_MAILBOX, loop);
213 
214 			sdsi_memcpy64_fromio(buf, priv->mbox_addr,
215 					     round_up(packet_size, SDSI_SIZE_CMD));
216 			total += packet_size;
217 		}
218 
219 		sdsi_complete_transaction(priv);
220 	} while (!eom && ++loop < MBOX_MAX_PACKETS);
221 
222 	if (ret) {
223 		sdsi_complete_transaction(priv);
224 		return ret;
225 	}
226 
227 	if (!eom) {
228 		dev_err(dev, "Exceeded read attempts\n");
229 		return -EPROTO;
230 	}
231 
232 	/* Message size check is only valid for multi-packet transfers */
233 	if (loop && total != message_size)
234 		dev_warn(dev, "Read count %u differs from expected count %u\n",
235 			 total, message_size);
236 
237 	if (data_size)
238 		*data_size = total;
239 
240 	return 0;
241 }
242 
sdsi_mbox_cmd_read(struct sdsi_priv * priv,struct sdsi_mbox_info * info,size_t * data_size)243 static int sdsi_mbox_cmd_read(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
244 			      size_t *data_size)
245 {
246 	u64 control;
247 
248 	lockdep_assert_held(&priv->mb_lock);
249 
250 	/* Format and send the read command */
251 	control = FIELD_PREP(CTRL_EOM, 1) |
252 		  FIELD_PREP(CTRL_SOM, 1) |
253 		  FIELD_PREP(CTRL_RUN_BUSY, 1) |
254 		  FIELD_PREP(CTRL_PACKET_SIZE, info->size) |
255 		  info->control_flags;
256 	writeq(control, priv->control_addr);
257 
258 	return sdsi_mbox_poll(priv, info, data_size);
259 }
260 
sdsi_mbox_cmd_write(struct sdsi_priv * priv,struct sdsi_mbox_info * info,size_t * data_size)261 static int sdsi_mbox_cmd_write(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
262 			       size_t *data_size)
263 {
264 	u64 control;
265 
266 	lockdep_assert_held(&priv->mb_lock);
267 
268 	/* Write rest of the payload */
269 	sdsi_memcpy64_toio(priv->mbox_addr + SDSI_SIZE_CMD, info->payload + 1,
270 			   info->size - SDSI_SIZE_CMD);
271 
272 	/* Format and send the write command */
273 	control = FIELD_PREP(CTRL_EOM, 1) |
274 		  FIELD_PREP(CTRL_SOM, 1) |
275 		  FIELD_PREP(CTRL_RUN_BUSY, 1) |
276 		  FIELD_PREP(CTRL_READ_WRITE, 1) |
277 		  FIELD_PREP(CTRL_MSG_SIZE, info->size) |
278 		  FIELD_PREP(CTRL_PACKET_SIZE, info->size);
279 	writeq(control, priv->control_addr);
280 
281 	return sdsi_mbox_poll(priv, info, data_size);
282 }
283 
sdsi_mbox_acquire(struct sdsi_priv * priv,struct sdsi_mbox_info * info)284 static int sdsi_mbox_acquire(struct sdsi_priv *priv, struct sdsi_mbox_info *info)
285 {
286 	u64 control;
287 	u32 owner;
288 	int ret, retries = 0;
289 
290 	lockdep_assert_held(&priv->mb_lock);
291 
292 	/* Check mailbox is available */
293 	control = readq(priv->control_addr);
294 	owner = FIELD_GET(CTRL_OWNER, control);
295 	if (owner != MBOX_OWNER_NONE)
296 		return -EBUSY;
297 
298 	/*
299 	 * If there has been no recent transaction and no one owns the mailbox,
300 	 * we should acquire it in under 1ms. However, if we've accessed it
301 	 * recently it may take up to 2.1 seconds to acquire it again.
302 	 */
303 	do {
304 		/* Write first qword of payload */
305 		writeq(info->payload[0], priv->mbox_addr);
306 
307 		/* Check for ownership */
308 		ret = readq_poll_timeout(priv->control_addr, control,
309 			FIELD_GET(CTRL_OWNER, control) == MBOX_OWNER_INBAND,
310 			MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_ACQUIRE_US);
311 
312 		if (FIELD_GET(CTRL_OWNER, control) == MBOX_OWNER_NONE &&
313 		    retries++ < MBOX_ACQUIRE_NUM_RETRIES) {
314 			msleep(MBOX_ACQUIRE_RETRY_DELAY_MS);
315 			continue;
316 		}
317 
318 		/* Either we got it or someone else did. */
319 		break;
320 	} while (true);
321 
322 	return ret;
323 }
324 
sdsi_mbox_write(struct sdsi_priv * priv,struct sdsi_mbox_info * info,size_t * data_size)325 static int sdsi_mbox_write(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
326 			   size_t *data_size)
327 {
328 	int ret;
329 
330 	lockdep_assert_held(&priv->mb_lock);
331 
332 	ret = sdsi_mbox_acquire(priv, info);
333 	if (ret)
334 		return ret;
335 
336 	return sdsi_mbox_cmd_write(priv, info, data_size);
337 }
338 
sdsi_mbox_read(struct sdsi_priv * priv,struct sdsi_mbox_info * info,size_t * data_size)339 static int sdsi_mbox_read(struct sdsi_priv *priv, struct sdsi_mbox_info *info, size_t *data_size)
340 {
341 	int ret;
342 
343 	lockdep_assert_held(&priv->mb_lock);
344 
345 	ret = sdsi_mbox_acquire(priv, info);
346 	if (ret)
347 		return ret;
348 
349 	return sdsi_mbox_cmd_read(priv, info, data_size);
350 }
351 
sdsi_ib_locked(struct sdsi_priv * priv)352 static bool sdsi_ib_locked(struct sdsi_priv *priv)
353 {
354 	return !!FIELD_GET(CTRL_INBAND_LOCK, readq(priv->control_addr));
355 }
356 
sdsi_provision(struct sdsi_priv * priv,char * buf,size_t count,enum sdsi_command command)357 static ssize_t sdsi_provision(struct sdsi_priv *priv, char *buf, size_t count,
358 			      enum sdsi_command command)
359 {
360 	struct sdsi_mbox_info info = {};
361 	int ret;
362 
363 	if (count > (SDSI_SIZE_WRITE_MSG - SDSI_SIZE_CMD))
364 		return -EOVERFLOW;
365 
366 	/* Make sure In-band lock is not set */
367 	if (sdsi_ib_locked(priv))
368 		return -EPERM;
369 
370 	/* Qword aligned message + command qword */
371 	info.size = round_up(count, SDSI_SIZE_CMD) + SDSI_SIZE_CMD;
372 
373 	info.payload = kzalloc(info.size, GFP_KERNEL);
374 	if (!info.payload)
375 		return -ENOMEM;
376 
377 	/* Copy message to payload buffer */
378 	memcpy(info.payload, buf, count);
379 
380 	/* Command is last qword of payload buffer */
381 	info.payload[(info.size - SDSI_SIZE_CMD) / SDSI_SIZE_CMD] = command;
382 
383 	ret = mutex_lock_interruptible(&priv->mb_lock);
384 	if (ret)
385 		goto free_payload;
386 
387 	ret = sdsi_mbox_write(priv, &info, NULL);
388 
389 	mutex_unlock(&priv->mb_lock);
390 
391 free_payload:
392 	kfree(info.payload);
393 
394 	if (ret)
395 		return ret;
396 
397 	return count;
398 }
399 
provision_akc_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)400 static ssize_t provision_akc_write(struct file *filp, struct kobject *kobj,
401 				   struct bin_attribute *attr, char *buf, loff_t off,
402 				   size_t count)
403 {
404 	struct device *dev = kobj_to_dev(kobj);
405 	struct sdsi_priv *priv = dev_get_drvdata(dev);
406 
407 	if (off)
408 		return -ESPIPE;
409 
410 	return sdsi_provision(priv, buf, count, SDSI_CMD_PROVISION_AKC);
411 }
412 static BIN_ATTR_WO(provision_akc, SDSI_SIZE_WRITE_MSG);
413 
provision_cap_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)414 static ssize_t provision_cap_write(struct file *filp, struct kobject *kobj,
415 				   struct bin_attribute *attr, char *buf, loff_t off,
416 				   size_t count)
417 {
418 	struct device *dev = kobj_to_dev(kobj);
419 	struct sdsi_priv *priv = dev_get_drvdata(dev);
420 
421 	if (off)
422 		return -ESPIPE;
423 
424 	return sdsi_provision(priv, buf, count, SDSI_CMD_PROVISION_CAP);
425 }
426 static BIN_ATTR_WO(provision_cap, SDSI_SIZE_WRITE_MSG);
427 
428 static ssize_t
certificate_read(u64 command,u64 control_flags,struct sdsi_priv * priv,char * buf,loff_t off,size_t count)429 certificate_read(u64 command, u64 control_flags, struct sdsi_priv *priv,
430 		 char *buf, loff_t off, size_t count)
431 {
432 	struct sdsi_mbox_info info = {};
433 	size_t size;
434 	int ret;
435 
436 	if (off)
437 		return 0;
438 
439 	/* Buffer for return data */
440 	info.buffer = kmalloc(SDSI_SIZE_READ_MSG, GFP_KERNEL);
441 	if (!info.buffer)
442 		return -ENOMEM;
443 
444 	info.payload = &command;
445 	info.size = sizeof(command);
446 	info.control_flags = control_flags;
447 
448 	ret = mutex_lock_interruptible(&priv->mb_lock);
449 	if (ret)
450 		goto free_buffer;
451 	ret = sdsi_mbox_read(priv, &info, &size);
452 	mutex_unlock(&priv->mb_lock);
453 	if (ret < 0)
454 		goto free_buffer;
455 
456 	if (size > count)
457 		size = count;
458 
459 	memcpy(buf, info.buffer, size);
460 
461 free_buffer:
462 	kfree(info.buffer);
463 
464 	if (ret)
465 		return ret;
466 
467 	return size;
468 }
469 
470 static ssize_t
state_certificate_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)471 state_certificate_read(struct file *filp, struct kobject *kobj,
472 		       struct bin_attribute *attr, char *buf, loff_t off,
473 		       size_t count)
474 {
475 	struct device *dev = kobj_to_dev(kobj);
476 	struct sdsi_priv *priv = dev_get_drvdata(dev);
477 
478 	return certificate_read(SDSI_CMD_READ_STATE, 0, priv, buf, off, count);
479 }
480 static BIN_ATTR_ADMIN_RO(state_certificate, SDSI_SIZE_READ_MSG);
481 
482 static ssize_t
meter_certificate_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)483 meter_certificate_read(struct file *filp, struct kobject *kobj,
484 		       struct bin_attribute *attr, char *buf, loff_t off,
485 		       size_t count)
486 {
487 	struct device *dev = kobj_to_dev(kobj);
488 	struct sdsi_priv *priv = dev_get_drvdata(dev);
489 
490 	return certificate_read(SDSI_CMD_READ_METER, 0, priv, buf, off, count);
491 }
492 static BIN_ATTR_ADMIN_RO(meter_certificate, SDSI_SIZE_READ_MSG);
493 
494 static ssize_t
meter_current_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)495 meter_current_read(struct file *filp, struct kobject *kobj,
496 		   struct bin_attribute *attr, char *buf, loff_t off,
497 		   size_t count)
498 {
499 	struct device *dev = kobj_to_dev(kobj);
500 	struct sdsi_priv *priv = dev_get_drvdata(dev);
501 
502 	return certificate_read(SDSI_CMD_READ_METER, CTRL_METER_ENABLE_DRAM,
503 				priv, buf, off, count);
504 }
505 static BIN_ATTR_ADMIN_RO(meter_current, SDSI_SIZE_READ_MSG);
506 
registers_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)507 static ssize_t registers_read(struct file *filp, struct kobject *kobj,
508 			      struct bin_attribute *attr, char *buf, loff_t off,
509 			      size_t count)
510 {
511 	struct device *dev = kobj_to_dev(kobj);
512 	struct sdsi_priv *priv = dev_get_drvdata(dev);
513 	void __iomem *addr = priv->regs_addr;
514 	int size =  priv->registers_size;
515 
516 	/*
517 	 * The check below is performed by the sysfs caller based on the static
518 	 * file size. But this may be greater than the actual size which is based
519 	 * on the GUID. So check here again based on actual size before reading.
520 	 */
521 	if (off >= size)
522 		return 0;
523 
524 	if (off + count > size)
525 		count = size - off;
526 
527 	memcpy_fromio(buf, addr + off, count);
528 
529 	return count;
530 }
531 static BIN_ATTR_ADMIN_RO(registers, SDSI_SIZE_REGS);
532 
533 static struct bin_attribute *sdsi_bin_attrs[] = {
534 	&bin_attr_registers,
535 	&bin_attr_state_certificate,
536 	&bin_attr_meter_certificate,
537 	&bin_attr_meter_current,
538 	&bin_attr_provision_akc,
539 	&bin_attr_provision_cap,
540 	NULL
541 };
542 
543 static umode_t
sdsi_battr_is_visible(struct kobject * kobj,struct bin_attribute * attr,int n)544 sdsi_battr_is_visible(struct kobject *kobj, struct bin_attribute *attr, int n)
545 {
546 	struct device *dev = kobj_to_dev(kobj);
547 	struct sdsi_priv *priv = dev_get_drvdata(dev);
548 
549 	/* Registers file is always readable if the device is present */
550 	if (attr == &bin_attr_registers)
551 		return attr->attr.mode;
552 
553 	/* All other attributes not visible if BIOS has not enabled On Demand */
554 	if (!(priv->features & SDSI_FEATURE_SDSI))
555 		return 0;
556 
557 	if (attr == &bin_attr_meter_certificate || attr == &bin_attr_meter_current)
558 		return (priv->features & SDSI_FEATURE_METERING) ?
559 				attr->attr.mode : 0;
560 
561 	return attr->attr.mode;
562 }
563 
guid_show(struct device * dev,struct device_attribute * attr,char * buf)564 static ssize_t guid_show(struct device *dev, struct device_attribute *attr, char *buf)
565 {
566 	struct sdsi_priv *priv = dev_get_drvdata(dev);
567 
568 	return sysfs_emit(buf, "0x%x\n", priv->guid);
569 }
570 static DEVICE_ATTR_RO(guid);
571 
572 static struct attribute *sdsi_attrs[] = {
573 	&dev_attr_guid.attr,
574 	NULL
575 };
576 
577 static const struct attribute_group sdsi_group = {
578 	.attrs = sdsi_attrs,
579 	.bin_attrs = sdsi_bin_attrs,
580 	.is_bin_visible = sdsi_battr_is_visible,
581 };
582 __ATTRIBUTE_GROUPS(sdsi);
583 
sdsi_get_layout(struct sdsi_priv * priv,struct disc_table * table)584 static int sdsi_get_layout(struct sdsi_priv *priv, struct disc_table *table)
585 {
586 	switch (table->guid) {
587 	case SDSI_GUID_V1:
588 		priv->control_size = GUID_V1_CNTRL_SIZE;
589 		priv->registers_size = GUID_V1_REGS_SIZE;
590 		break;
591 	case SDSI_GUID_V2:
592 		priv->control_size = GUID_V2_CNTRL_SIZE;
593 		priv->registers_size = GUID_V2_REGS_SIZE;
594 		break;
595 	default:
596 		dev_err(priv->dev, "Unrecognized GUID 0x%x\n", table->guid);
597 		return -EINVAL;
598 	}
599 	return 0;
600 }
601 
sdsi_map_mbox_registers(struct sdsi_priv * priv,struct pci_dev * parent,struct disc_table * disc_table,struct resource * disc_res)602 static int sdsi_map_mbox_registers(struct sdsi_priv *priv, struct pci_dev *parent,
603 				   struct disc_table *disc_table, struct resource *disc_res)
604 {
605 	u32 access_type = FIELD_GET(DT_ACCESS_TYPE, disc_table->access_info);
606 	u32 size = FIELD_GET(DT_SIZE, disc_table->access_info);
607 	u32 tbir = FIELD_GET(DT_TBIR, disc_table->offset);
608 	u32 offset = DT_OFFSET(disc_table->offset);
609 	struct resource res = {};
610 
611 	/* Starting location of SDSi MMIO region based on access type */
612 	switch (access_type) {
613 	case ACCESS_TYPE_LOCAL:
614 		if (tbir) {
615 			dev_err(priv->dev, "Unsupported BAR index %u for access type %u\n",
616 				tbir, access_type);
617 			return -EINVAL;
618 		}
619 
620 		/*
621 		 * For access_type LOCAL, the base address is as follows:
622 		 * base address = end of discovery region + base offset + 1
623 		 */
624 		res.start = disc_res->end + offset + 1;
625 		break;
626 
627 	case ACCESS_TYPE_BARID:
628 		res.start = pci_resource_start(parent, tbir) + offset;
629 		break;
630 
631 	default:
632 		dev_err(priv->dev, "Unrecognized access_type %u\n", access_type);
633 		return -EINVAL;
634 	}
635 
636 	res.end = res.start + size * sizeof(u32) - 1;
637 	res.flags = IORESOURCE_MEM;
638 
639 	priv->control_addr = devm_ioremap_resource(priv->dev, &res);
640 	if (IS_ERR(priv->control_addr))
641 		return PTR_ERR(priv->control_addr);
642 
643 	priv->mbox_addr = priv->control_addr + priv->control_size;
644 	priv->regs_addr = priv->mbox_addr + SDSI_SIZE_MAILBOX;
645 
646 	priv->features = readq(priv->regs_addr + SDSI_ENABLED_FEATURES_OFFSET);
647 
648 	return 0;
649 }
650 
sdsi_probe(struct auxiliary_device * auxdev,const struct auxiliary_device_id * id)651 static int sdsi_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id)
652 {
653 	struct intel_vsec_device *intel_cap_dev = auxdev_to_ivdev(auxdev);
654 	struct disc_table disc_table;
655 	struct resource *disc_res;
656 	void __iomem *disc_addr;
657 	struct sdsi_priv *priv;
658 	int ret;
659 
660 	priv = devm_kzalloc(&auxdev->dev, sizeof(*priv), GFP_KERNEL);
661 	if (!priv)
662 		return -ENOMEM;
663 
664 	priv->dev = &auxdev->dev;
665 	mutex_init(&priv->mb_lock);
666 	auxiliary_set_drvdata(auxdev, priv);
667 
668 	/* Get the SDSi discovery table */
669 	disc_res = &intel_cap_dev->resource[0];
670 	disc_addr = devm_ioremap_resource(&auxdev->dev, disc_res);
671 	if (IS_ERR(disc_addr))
672 		return PTR_ERR(disc_addr);
673 
674 	memcpy_fromio(&disc_table, disc_addr, DISC_TABLE_SIZE);
675 
676 	priv->guid = disc_table.guid;
677 
678 	/* Get guid based layout info */
679 	ret = sdsi_get_layout(priv, &disc_table);
680 	if (ret)
681 		return ret;
682 
683 	/* Map the SDSi mailbox registers */
684 	ret = sdsi_map_mbox_registers(priv, intel_cap_dev->pcidev, &disc_table, disc_res);
685 	if (ret)
686 		return ret;
687 
688 	return 0;
689 }
690 
691 static const struct auxiliary_device_id sdsi_aux_id_table[] = {
692 	{ .name = "intel_vsec.sdsi" },
693 	{}
694 };
695 MODULE_DEVICE_TABLE(auxiliary, sdsi_aux_id_table);
696 
697 static struct auxiliary_driver sdsi_aux_driver = {
698 	.driver = {
699 		.dev_groups = sdsi_groups,
700 	},
701 	.id_table	= sdsi_aux_id_table,
702 	.probe		= sdsi_probe,
703 	/* No remove. All resources are handled under devm */
704 };
705 module_auxiliary_driver(sdsi_aux_driver);
706 
707 MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
708 MODULE_DESCRIPTION("Intel On Demand (SDSi) driver");
709 MODULE_LICENSE("GPL");
710