xref: /linux/drivers/platform/x86/amd/hsmp.c (revision dbcedec3a31119d7594baacc743300d127c99c56)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AMD HSMP Platform Driver
4  * Copyright (c) 2022, AMD.
5  * All Rights Reserved.
6  *
7  * This file provides a device implementation for HSMP interface
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <asm/amd_hsmp.h>
13 #include <asm/amd_nb.h>
14 #include <linux/delay.h>
15 #include <linux/io.h>
16 #include <linux/miscdevice.h>
17 #include <linux/module.h>
18 #include <linux/pci.h>
19 #include <linux/platform_device.h>
20 #include <linux/semaphore.h>
21 #include <linux/acpi.h>
22 
23 #define DRIVER_NAME		"amd_hsmp"
24 #define DRIVER_VERSION		"2.2"
25 #define ACPI_HSMP_DEVICE_HID	"AMDI0097"
26 
27 /* HSMP Status / Error codes */
28 #define HSMP_STATUS_NOT_READY	0x00
29 #define HSMP_STATUS_OK		0x01
30 #define HSMP_ERR_INVALID_MSG	0xFE
31 #define HSMP_ERR_INVALID_INPUT	0xFF
32 
33 /* Timeout in millsec */
34 #define HSMP_MSG_TIMEOUT	100
35 #define HSMP_SHORT_SLEEP	1
36 
37 #define HSMP_WR			true
38 #define HSMP_RD			false
39 
40 /*
41  * To access specific HSMP mailbox register, s/w writes the SMN address of HSMP mailbox
42  * register into the SMN_INDEX register, and reads/writes the SMN_DATA reg.
43  * Below are required SMN address for HSMP Mailbox register offsets in SMU address space
44  */
45 #define SMN_HSMP_BASE		0x3B00000
46 #define SMN_HSMP_MSG_ID		0x0010534
47 #define SMN_HSMP_MSG_ID_F1A_M0H	0x0010934
48 #define SMN_HSMP_MSG_RESP	0x0010980
49 #define SMN_HSMP_MSG_DATA	0x00109E0
50 
51 #define HSMP_INDEX_REG		0xc4
52 #define HSMP_DATA_REG		0xc8
53 
54 #define HSMP_CDEV_NAME		"hsmp_cdev"
55 #define HSMP_DEVNODE_NAME	"hsmp"
56 #define HSMP_METRICS_TABLE_NAME	"metrics_bin"
57 
58 #define HSMP_ATTR_GRP_NAME_SIZE	10
59 
60 /* These are the strings specified in ACPI table */
61 #define MSG_IDOFF_STR		"MsgIdOffset"
62 #define MSG_ARGOFF_STR		"MsgArgOffset"
63 #define MSG_RESPOFF_STR		"MsgRspOffset"
64 
65 #define MAX_AMD_SOCKETS 8
66 
67 struct hsmp_mbaddr_info {
68 	u32 base_addr;
69 	u32 msg_id_off;
70 	u32 msg_resp_off;
71 	u32 msg_arg_off;
72 	u32 size;
73 };
74 
75 struct hsmp_socket {
76 	struct bin_attribute hsmp_attr;
77 	struct hsmp_mbaddr_info mbinfo;
78 	void __iomem *metric_tbl_addr;
79 	void __iomem *virt_base_addr;
80 	struct semaphore hsmp_sem;
81 	char name[HSMP_ATTR_GRP_NAME_SIZE];
82 	struct pci_dev *root;
83 	struct device *dev;
84 	u16 sock_ind;
85 };
86 
87 struct hsmp_plat_device {
88 	struct miscdevice hsmp_device;
89 	struct hsmp_socket *sock;
90 	u32 proto_ver;
91 	u16 num_sockets;
92 	bool is_acpi_device;
93 	bool is_probed;
94 };
95 
96 static struct hsmp_plat_device plat_dev;
97 
98 static int amd_hsmp_pci_rdwr(struct hsmp_socket *sock, u32 offset,
99 			     u32 *value, bool write)
100 {
101 	int ret;
102 
103 	if (!sock->root)
104 		return -ENODEV;
105 
106 	ret = pci_write_config_dword(sock->root, HSMP_INDEX_REG,
107 				     sock->mbinfo.base_addr + offset);
108 	if (ret)
109 		return ret;
110 
111 	ret = (write ? pci_write_config_dword(sock->root, HSMP_DATA_REG, *value)
112 		     : pci_read_config_dword(sock->root, HSMP_DATA_REG, value));
113 
114 	return ret;
115 }
116 
117 static void amd_hsmp_acpi_rdwr(struct hsmp_socket *sock, u32 offset,
118 			       u32 *value, bool write)
119 {
120 	if (write)
121 		iowrite32(*value, sock->virt_base_addr + offset);
122 	else
123 		*value = ioread32(sock->virt_base_addr + offset);
124 }
125 
126 static int amd_hsmp_rdwr(struct hsmp_socket *sock, u32 offset,
127 			 u32 *value, bool write)
128 {
129 	if (plat_dev.is_acpi_device)
130 		amd_hsmp_acpi_rdwr(sock, offset, value, write);
131 	else
132 		return amd_hsmp_pci_rdwr(sock, offset, value, write);
133 
134 	return 0;
135 }
136 
137 /*
138  * Send a message to the HSMP port via PCI-e config space registers
139  * or by writing to MMIO space.
140  *
141  * The caller is expected to zero out any unused arguments.
142  * If a response is expected, the number of response words should be greater than 0.
143  *
144  * Returns 0 for success and populates the requested number of arguments.
145  * Returns a negative error code for failure.
146  */
147 static int __hsmp_send_message(struct hsmp_socket *sock, struct hsmp_message *msg)
148 {
149 	struct hsmp_mbaddr_info *mbinfo;
150 	unsigned long timeout, short_sleep;
151 	u32 mbox_status;
152 	u32 index;
153 	int ret;
154 
155 	mbinfo = &sock->mbinfo;
156 
157 	/* Clear the status register */
158 	mbox_status = HSMP_STATUS_NOT_READY;
159 	ret = amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_WR);
160 	if (ret) {
161 		pr_err("Error %d clearing mailbox status register\n", ret);
162 		return ret;
163 	}
164 
165 	index = 0;
166 	/* Write any message arguments */
167 	while (index < msg->num_args) {
168 		ret = amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
169 				    &msg->args[index], HSMP_WR);
170 		if (ret) {
171 			pr_err("Error %d writing message argument %d\n", ret, index);
172 			return ret;
173 		}
174 		index++;
175 	}
176 
177 	/* Write the message ID which starts the operation */
178 	ret = amd_hsmp_rdwr(sock, mbinfo->msg_id_off, &msg->msg_id, HSMP_WR);
179 	if (ret) {
180 		pr_err("Error %d writing message ID %u\n", ret, msg->msg_id);
181 		return ret;
182 	}
183 
184 	/*
185 	 * Depending on when the trigger write completes relative to the SMU
186 	 * firmware 1 ms cycle, the operation may take from tens of us to 1 ms
187 	 * to complete. Some operations may take more. Therefore we will try
188 	 * a few short duration sleeps and switch to long sleeps if we don't
189 	 * succeed quickly.
190 	 */
191 	short_sleep = jiffies + msecs_to_jiffies(HSMP_SHORT_SLEEP);
192 	timeout	= jiffies + msecs_to_jiffies(HSMP_MSG_TIMEOUT);
193 
194 	while (time_before(jiffies, timeout)) {
195 		ret = amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_RD);
196 		if (ret) {
197 			pr_err("Error %d reading mailbox status\n", ret);
198 			return ret;
199 		}
200 
201 		if (mbox_status != HSMP_STATUS_NOT_READY)
202 			break;
203 		if (time_before(jiffies, short_sleep))
204 			usleep_range(50, 100);
205 		else
206 			usleep_range(1000, 2000);
207 	}
208 
209 	if (unlikely(mbox_status == HSMP_STATUS_NOT_READY)) {
210 		return -ETIMEDOUT;
211 	} else if (unlikely(mbox_status == HSMP_ERR_INVALID_MSG)) {
212 		return -ENOMSG;
213 	} else if (unlikely(mbox_status == HSMP_ERR_INVALID_INPUT)) {
214 		return -EINVAL;
215 	} else if (unlikely(mbox_status != HSMP_STATUS_OK)) {
216 		pr_err("Message ID %u unknown failure (status = 0x%X)\n",
217 		       msg->msg_id, mbox_status);
218 		return -EIO;
219 	}
220 
221 	/*
222 	 * SMU has responded OK. Read response data.
223 	 * SMU reads the input arguments from eight 32 bit registers starting
224 	 * from SMN_HSMP_MSG_DATA and writes the response data to the same
225 	 * SMN_HSMP_MSG_DATA address.
226 	 * We copy the response data if any, back to the args[].
227 	 */
228 	index = 0;
229 	while (index < msg->response_sz) {
230 		ret = amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
231 				    &msg->args[index], HSMP_RD);
232 		if (ret) {
233 			pr_err("Error %d reading response %u for message ID:%u\n",
234 			       ret, index, msg->msg_id);
235 			break;
236 		}
237 		index++;
238 	}
239 
240 	return ret;
241 }
242 
243 static int validate_message(struct hsmp_message *msg)
244 {
245 	/* msg_id against valid range of message IDs */
246 	if (msg->msg_id < HSMP_TEST || msg->msg_id >= HSMP_MSG_ID_MAX)
247 		return -ENOMSG;
248 
249 	/* msg_id is a reserved message ID */
250 	if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_RSVD)
251 		return -ENOMSG;
252 
253 	/* num_args and response_sz against the HSMP spec */
254 	if (msg->num_args != hsmp_msg_desc_table[msg->msg_id].num_args ||
255 	    msg->response_sz != hsmp_msg_desc_table[msg->msg_id].response_sz)
256 		return -EINVAL;
257 
258 	return 0;
259 }
260 
261 int hsmp_send_message(struct hsmp_message *msg)
262 {
263 	struct hsmp_socket *sock;
264 	int ret;
265 
266 	if (!msg)
267 		return -EINVAL;
268 	ret = validate_message(msg);
269 	if (ret)
270 		return ret;
271 
272 	if (!plat_dev.sock || msg->sock_ind >= plat_dev.num_sockets)
273 		return -ENODEV;
274 	sock = &plat_dev.sock[msg->sock_ind];
275 
276 	/*
277 	 * The time taken by smu operation to complete is between
278 	 * 10us to 1ms. Sometime it may take more time.
279 	 * In SMP system timeout of 100 millisecs should
280 	 * be enough for the previous thread to finish the operation
281 	 */
282 	ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));
283 	if (ret < 0)
284 		return ret;
285 
286 	ret = __hsmp_send_message(sock, msg);
287 
288 	up(&sock->hsmp_sem);
289 
290 	return ret;
291 }
292 EXPORT_SYMBOL_GPL(hsmp_send_message);
293 
294 static int hsmp_test(u16 sock_ind, u32 value)
295 {
296 	struct hsmp_message msg = { 0 };
297 	int ret;
298 
299 	/*
300 	 * Test the hsmp port by performing TEST command. The test message
301 	 * takes one argument and returns the value of that argument + 1.
302 	 */
303 	msg.msg_id	= HSMP_TEST;
304 	msg.num_args	= 1;
305 	msg.response_sz	= 1;
306 	msg.args[0]	= value;
307 	msg.sock_ind	= sock_ind;
308 
309 	ret = hsmp_send_message(&msg);
310 	if (ret)
311 		return ret;
312 
313 	/* Check the response value */
314 	if (msg.args[0] != (value + 1)) {
315 		dev_err(plat_dev.sock[sock_ind].dev,
316 			"Socket %d test message failed, Expected 0x%08X, received 0x%08X\n",
317 			sock_ind, (value + 1), msg.args[0]);
318 		return -EBADE;
319 	}
320 
321 	return ret;
322 }
323 
324 static long hsmp_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
325 {
326 	int __user *arguser = (int  __user *)arg;
327 	struct hsmp_message msg = { 0 };
328 	int ret;
329 
330 	if (copy_struct_from_user(&msg, sizeof(msg), arguser, sizeof(struct hsmp_message)))
331 		return -EFAULT;
332 
333 	/*
334 	 * Check msg_id is within the range of supported msg ids
335 	 * i.e within the array bounds of hsmp_msg_desc_table
336 	 */
337 	if (msg.msg_id < HSMP_TEST || msg.msg_id >= HSMP_MSG_ID_MAX)
338 		return -ENOMSG;
339 
340 	switch (fp->f_mode & (FMODE_WRITE | FMODE_READ)) {
341 	case FMODE_WRITE:
342 		/*
343 		 * Device is opened in O_WRONLY mode
344 		 * Execute only set/configure commands
345 		 */
346 		if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_SET)
347 			return -EINVAL;
348 		break;
349 	case FMODE_READ:
350 		/*
351 		 * Device is opened in O_RDONLY mode
352 		 * Execute only get/monitor commands
353 		 */
354 		if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_GET)
355 			return -EINVAL;
356 		break;
357 	case FMODE_READ | FMODE_WRITE:
358 		/*
359 		 * Device is opened in O_RDWR mode
360 		 * Execute both get/monitor and set/configure commands
361 		 */
362 		break;
363 	default:
364 		return -EINVAL;
365 	}
366 
367 	ret = hsmp_send_message(&msg);
368 	if (ret)
369 		return ret;
370 
371 	if (hsmp_msg_desc_table[msg.msg_id].response_sz > 0) {
372 		/* Copy results back to user for get/monitor commands */
373 		if (copy_to_user(arguser, &msg, sizeof(struct hsmp_message)))
374 			return -EFAULT;
375 	}
376 
377 	return 0;
378 }
379 
380 static const struct file_operations hsmp_fops = {
381 	.owner		= THIS_MODULE,
382 	.unlocked_ioctl	= hsmp_ioctl,
383 	.compat_ioctl	= hsmp_ioctl,
384 };
385 
386 /* This is the UUID used for HSMP */
387 static const guid_t acpi_hsmp_uuid = GUID_INIT(0xb74d619d, 0x5707, 0x48bd,
388 						0xa6, 0x9f, 0x4e, 0xa2,
389 						0x87, 0x1f, 0xc2, 0xf6);
390 
391 static inline bool is_acpi_hsmp_uuid(union acpi_object *obj)
392 {
393 	if (obj->type == ACPI_TYPE_BUFFER && obj->buffer.length == UUID_SIZE)
394 		return guid_equal((guid_t *)obj->buffer.pointer, &acpi_hsmp_uuid);
395 
396 	return false;
397 }
398 
399 static inline int hsmp_get_uid(struct device *dev, u16 *sock_ind)
400 {
401 	char *uid;
402 
403 	/*
404 	 * UID (ID00, ID01..IDXX) is used for differentiating sockets,
405 	 * read it and strip the "ID" part of it and convert the remaining
406 	 * bytes to integer.
407 	 */
408 	uid = acpi_device_uid(ACPI_COMPANION(dev));
409 
410 	return kstrtou16(uid + 2, 10, sock_ind);
411 }
412 
413 static acpi_status hsmp_resource(struct acpi_resource *res, void *data)
414 {
415 	struct hsmp_socket *sock = data;
416 	struct resource r;
417 
418 	switch (res->type) {
419 	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
420 		if (!acpi_dev_resource_memory(res, &r))
421 			return AE_ERROR;
422 		if (!r.start || r.end < r.start || !(r.flags & IORESOURCE_MEM_WRITEABLE))
423 			return AE_ERROR;
424 		sock->mbinfo.base_addr = r.start;
425 		sock->mbinfo.size = resource_size(&r);
426 		break;
427 	case ACPI_RESOURCE_TYPE_END_TAG:
428 		break;
429 	default:
430 		return AE_ERROR;
431 	}
432 
433 	return AE_OK;
434 }
435 
436 static int hsmp_read_acpi_dsd(struct hsmp_socket *sock)
437 {
438 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
439 	union acpi_object *guid, *mailbox_package;
440 	union acpi_object *dsd;
441 	acpi_status status;
442 	int ret = 0;
443 	int j;
444 
445 	status = acpi_evaluate_object_typed(ACPI_HANDLE(sock->dev), "_DSD", NULL,
446 					    &buf, ACPI_TYPE_PACKAGE);
447 	if (ACPI_FAILURE(status)) {
448 		dev_err(sock->dev, "Failed to read mailbox reg offsets from DSD table, err: %s\n",
449 			acpi_format_exception(status));
450 		return -ENODEV;
451 	}
452 
453 	dsd = buf.pointer;
454 
455 	/* HSMP _DSD property should contain 2 objects.
456 	 * 1. guid which is an acpi object of type ACPI_TYPE_BUFFER
457 	 * 2. mailbox which is an acpi object of type ACPI_TYPE_PACKAGE
458 	 *    This mailbox object contains 3 more acpi objects of type
459 	 *    ACPI_TYPE_PACKAGE for holding msgid, msgresp, msgarg offsets
460 	 *    these packages inturn contain 2 acpi objects of type
461 	 *    ACPI_TYPE_STRING and ACPI_TYPE_INTEGER
462 	 */
463 	if (!dsd || dsd->type != ACPI_TYPE_PACKAGE || dsd->package.count != 2) {
464 		ret = -EINVAL;
465 		goto free_buf;
466 	}
467 
468 	guid = &dsd->package.elements[0];
469 	mailbox_package = &dsd->package.elements[1];
470 	if (!is_acpi_hsmp_uuid(guid) || mailbox_package->type != ACPI_TYPE_PACKAGE) {
471 		dev_err(sock->dev, "Invalid hsmp _DSD table data\n");
472 		ret = -EINVAL;
473 		goto free_buf;
474 	}
475 
476 	for (j = 0; j < mailbox_package->package.count; j++) {
477 		union acpi_object *msgobj, *msgstr, *msgint;
478 
479 		msgobj	= &mailbox_package->package.elements[j];
480 		msgstr	= &msgobj->package.elements[0];
481 		msgint	= &msgobj->package.elements[1];
482 
483 		/* package should have 1 string and 1 integer object */
484 		if (msgobj->type != ACPI_TYPE_PACKAGE ||
485 		    msgstr->type != ACPI_TYPE_STRING ||
486 		    msgint->type != ACPI_TYPE_INTEGER) {
487 			ret = -EINVAL;
488 			goto free_buf;
489 		}
490 
491 		if (!strncmp(msgstr->string.pointer, MSG_IDOFF_STR,
492 			     msgstr->string.length)) {
493 			sock->mbinfo.msg_id_off = msgint->integer.value;
494 		} else if (!strncmp(msgstr->string.pointer, MSG_RESPOFF_STR,
495 				    msgstr->string.length)) {
496 			sock->mbinfo.msg_resp_off =  msgint->integer.value;
497 		} else if (!strncmp(msgstr->string.pointer, MSG_ARGOFF_STR,
498 				    msgstr->string.length)) {
499 			sock->mbinfo.msg_arg_off = msgint->integer.value;
500 		} else {
501 			ret = -ENOENT;
502 			goto free_buf;
503 		}
504 	}
505 
506 	if (!sock->mbinfo.msg_id_off || !sock->mbinfo.msg_resp_off ||
507 	    !sock->mbinfo.msg_arg_off)
508 		ret = -EINVAL;
509 
510 free_buf:
511 	ACPI_FREE(buf.pointer);
512 	return ret;
513 }
514 
515 static int hsmp_read_acpi_crs(struct hsmp_socket *sock)
516 {
517 	acpi_status status;
518 
519 	status = acpi_walk_resources(ACPI_HANDLE(sock->dev), METHOD_NAME__CRS,
520 				     hsmp_resource, sock);
521 	if (ACPI_FAILURE(status)) {
522 		dev_err(sock->dev, "Failed to look up MP1 base address from CRS method, err: %s\n",
523 			acpi_format_exception(status));
524 		return -EINVAL;
525 	}
526 	if (!sock->mbinfo.base_addr || !sock->mbinfo.size)
527 		return -EINVAL;
528 
529 	/* The mapped region should be un cached */
530 	sock->virt_base_addr = devm_ioremap_uc(sock->dev, sock->mbinfo.base_addr,
531 					       sock->mbinfo.size);
532 	if (!sock->virt_base_addr) {
533 		dev_err(sock->dev, "Failed to ioremap MP1 base address\n");
534 		return -ENOMEM;
535 	}
536 
537 	return 0;
538 }
539 
540 /* Parse the ACPI table to read the data */
541 static int hsmp_parse_acpi_table(struct device *dev, u16 sock_ind)
542 {
543 	struct hsmp_socket *sock = &plat_dev.sock[sock_ind];
544 	int ret;
545 
546 	sock->sock_ind		= sock_ind;
547 	sock->dev		= dev;
548 	plat_dev.is_acpi_device	= true;
549 
550 	sema_init(&sock->hsmp_sem, 1);
551 
552 	/* Read MP1 base address from CRS method */
553 	ret = hsmp_read_acpi_crs(sock);
554 	if (ret)
555 		return ret;
556 
557 	/* Read mailbox offsets from DSD table */
558 	return hsmp_read_acpi_dsd(sock);
559 }
560 
561 static ssize_t hsmp_metric_tbl_read(struct file *filp, struct kobject *kobj,
562 				    struct bin_attribute *bin_attr, char *buf,
563 				    loff_t off, size_t count)
564 {
565 	struct hsmp_socket *sock = bin_attr->private;
566 	struct hsmp_message msg = { 0 };
567 	int ret;
568 
569 	if (!sock)
570 		return -EINVAL;
571 
572 	/* Do not support lseek(), reads entire metric table */
573 	if (count < bin_attr->size) {
574 		dev_err(sock->dev, "Wrong buffer size\n");
575 		return -EINVAL;
576 	}
577 
578 	msg.msg_id	= HSMP_GET_METRIC_TABLE;
579 	msg.sock_ind	= sock->sock_ind;
580 
581 	ret = hsmp_send_message(&msg);
582 	if (ret)
583 		return ret;
584 	memcpy_fromio(buf, sock->metric_tbl_addr, bin_attr->size);
585 
586 	return bin_attr->size;
587 }
588 
589 static int hsmp_get_tbl_dram_base(u16 sock_ind)
590 {
591 	struct hsmp_socket *sock = &plat_dev.sock[sock_ind];
592 	struct hsmp_message msg = { 0 };
593 	phys_addr_t dram_addr;
594 	int ret;
595 
596 	msg.sock_ind	= sock_ind;
597 	msg.response_sz	= hsmp_msg_desc_table[HSMP_GET_METRIC_TABLE_DRAM_ADDR].response_sz;
598 	msg.msg_id	= HSMP_GET_METRIC_TABLE_DRAM_ADDR;
599 
600 	ret = hsmp_send_message(&msg);
601 	if (ret)
602 		return ret;
603 
604 	/*
605 	 * calculate the metric table DRAM address from lower and upper 32 bits
606 	 * sent from SMU and ioremap it to virtual address.
607 	 */
608 	dram_addr = msg.args[0] | ((u64)(msg.args[1]) << 32);
609 	if (!dram_addr) {
610 		dev_err(sock->dev, "Invalid DRAM address for metric table\n");
611 		return -ENOMEM;
612 	}
613 	sock->metric_tbl_addr = devm_ioremap(sock->dev, dram_addr,
614 					     sizeof(struct hsmp_metric_table));
615 	if (!sock->metric_tbl_addr) {
616 		dev_err(sock->dev, "Failed to ioremap metric table addr\n");
617 		return -ENOMEM;
618 	}
619 	return 0;
620 }
621 
622 static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
623 					 struct bin_attribute *battr, int id)
624 {
625 	if (plat_dev.proto_ver == HSMP_PROTO_VER6)
626 		return battr->attr.mode;
627 	else
628 		return 0;
629 }
630 
631 static int hsmp_init_metric_tbl_bin_attr(struct bin_attribute **hattrs, u16 sock_ind)
632 {
633 	struct bin_attribute *hattr = &plat_dev.sock[sock_ind].hsmp_attr;
634 
635 	sysfs_bin_attr_init(hattr);
636 	hattr->attr.name	= HSMP_METRICS_TABLE_NAME;
637 	hattr->attr.mode	= 0444;
638 	hattr->read		= hsmp_metric_tbl_read;
639 	hattr->size		= sizeof(struct hsmp_metric_table);
640 	hattr->private		= &plat_dev.sock[sock_ind];
641 	hattrs[0]		= hattr;
642 
643 	if (plat_dev.proto_ver == HSMP_PROTO_VER6)
644 		return hsmp_get_tbl_dram_base(sock_ind);
645 	else
646 		return 0;
647 }
648 
649 /* One bin sysfs for metrics table */
650 #define NUM_HSMP_ATTRS		1
651 
652 static int hsmp_create_attr_list(struct attribute_group *attr_grp,
653 				 struct device *dev, u16 sock_ind)
654 {
655 	struct bin_attribute **hsmp_bin_attrs;
656 
657 	/* Null terminated list of attributes */
658 	hsmp_bin_attrs = devm_kcalloc(dev, NUM_HSMP_ATTRS + 1,
659 				      sizeof(*hsmp_bin_attrs),
660 				      GFP_KERNEL);
661 	if (!hsmp_bin_attrs)
662 		return -ENOMEM;
663 
664 	attr_grp->bin_attrs = hsmp_bin_attrs;
665 
666 	return hsmp_init_metric_tbl_bin_attr(hsmp_bin_attrs, sock_ind);
667 }
668 
669 static int hsmp_create_non_acpi_sysfs_if(struct device *dev)
670 {
671 	const struct attribute_group **hsmp_attr_grps;
672 	struct attribute_group *attr_grp;
673 	u16 i;
674 
675 	hsmp_attr_grps = devm_kcalloc(dev, plat_dev.num_sockets + 1,
676 				      sizeof(*hsmp_attr_grps),
677 				      GFP_KERNEL);
678 	if (!hsmp_attr_grps)
679 		return -ENOMEM;
680 
681 	/* Create a sysfs directory for each socket */
682 	for (i = 0; i < plat_dev.num_sockets; i++) {
683 		attr_grp = devm_kzalloc(dev, sizeof(struct attribute_group),
684 					GFP_KERNEL);
685 		if (!attr_grp)
686 			return -ENOMEM;
687 
688 		snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE, "socket%u", (u8)i);
689 		attr_grp->name			= plat_dev.sock[i].name;
690 		attr_grp->is_bin_visible	= hsmp_is_sock_attr_visible;
691 		hsmp_attr_grps[i]		= attr_grp;
692 
693 		hsmp_create_attr_list(attr_grp, dev, i);
694 	}
695 
696 	return devm_device_add_groups(dev, hsmp_attr_grps);
697 }
698 
699 static int hsmp_create_acpi_sysfs_if(struct device *dev)
700 {
701 	struct attribute_group *attr_grp;
702 	u16 sock_ind;
703 	int ret;
704 
705 	attr_grp = devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
706 	if (!attr_grp)
707 		return -ENOMEM;
708 
709 	attr_grp->is_bin_visible = hsmp_is_sock_attr_visible;
710 
711 	ret = hsmp_get_uid(dev, &sock_ind);
712 	if (ret)
713 		return ret;
714 
715 	ret = hsmp_create_attr_list(attr_grp, dev, sock_ind);
716 	if (ret)
717 		return ret;
718 
719 	return devm_device_add_group(dev, attr_grp);
720 }
721 
722 static int hsmp_cache_proto_ver(u16 sock_ind)
723 {
724 	struct hsmp_message msg = { 0 };
725 	int ret;
726 
727 	msg.msg_id	= HSMP_GET_PROTO_VER;
728 	msg.sock_ind	= sock_ind;
729 	msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz;
730 
731 	ret = hsmp_send_message(&msg);
732 	if (!ret)
733 		plat_dev.proto_ver = msg.args[0];
734 
735 	return ret;
736 }
737 
738 static inline bool is_f1a_m0h(void)
739 {
740 	if (boot_cpu_data.x86 == 0x1A && boot_cpu_data.x86_model <= 0x0F)
741 		return true;
742 
743 	return false;
744 }
745 
746 static int init_platform_device(struct device *dev)
747 {
748 	struct hsmp_socket *sock;
749 	int ret, i;
750 
751 	for (i = 0; i < plat_dev.num_sockets; i++) {
752 		if (!node_to_amd_nb(i))
753 			return -ENODEV;
754 		sock = &plat_dev.sock[i];
755 		sock->root			= node_to_amd_nb(i)->root;
756 		sock->sock_ind			= i;
757 		sock->dev			= dev;
758 		sock->mbinfo.base_addr		= SMN_HSMP_BASE;
759 
760 		/*
761 		 * This is a transitional change from non-ACPI to ACPI, only
762 		 * family 0x1A, model 0x00 platform is supported for both ACPI and non-ACPI.
763 		 */
764 		if (is_f1a_m0h())
765 			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID_F1A_M0H;
766 		else
767 			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID;
768 
769 		sock->mbinfo.msg_resp_off	= SMN_HSMP_MSG_RESP;
770 		sock->mbinfo.msg_arg_off	= SMN_HSMP_MSG_DATA;
771 		sema_init(&sock->hsmp_sem, 1);
772 
773 		/* Test the hsmp interface on each socket */
774 		ret = hsmp_test(i, 0xDEADBEEF);
775 		if (ret) {
776 			dev_err(dev, "HSMP test message failed on Fam:%x model:%x\n",
777 				boot_cpu_data.x86, boot_cpu_data.x86_model);
778 			dev_err(dev, "Is HSMP disabled in BIOS ?\n");
779 			return ret;
780 		}
781 	}
782 
783 	return 0;
784 }
785 
786 static const struct acpi_device_id amd_hsmp_acpi_ids[] = {
787 	{ACPI_HSMP_DEVICE_HID, 0},
788 	{}
789 };
790 MODULE_DEVICE_TABLE(acpi, amd_hsmp_acpi_ids);
791 
792 static int hsmp_pltdrv_probe(struct platform_device *pdev)
793 {
794 	struct acpi_device *adev;
795 	u16 sock_ind = 0;
796 	int ret;
797 
798 	/*
799 	 * On ACPI supported BIOS, there is an ACPI HSMP device added for
800 	 * each socket, so the per socket probing, but the memory allocated for
801 	 * sockets should be contiguous to access it as an array,
802 	 * Hence allocate memory for all the sockets at once instead of allocating
803 	 * on each probe.
804 	 */
805 	if (!plat_dev.is_probed) {
806 		plat_dev.sock = devm_kcalloc(&pdev->dev, plat_dev.num_sockets,
807 					     sizeof(*plat_dev.sock),
808 					     GFP_KERNEL);
809 		if (!plat_dev.sock)
810 			return -ENOMEM;
811 	}
812 	adev = ACPI_COMPANION(&pdev->dev);
813 	if (adev && !acpi_match_device_ids(adev, amd_hsmp_acpi_ids)) {
814 		ret = hsmp_get_uid(&pdev->dev, &sock_ind);
815 		if (ret)
816 			return ret;
817 		if (sock_ind >= plat_dev.num_sockets)
818 			return -EINVAL;
819 		ret = hsmp_parse_acpi_table(&pdev->dev, sock_ind);
820 		if (ret) {
821 			dev_err(&pdev->dev, "Failed to parse ACPI table\n");
822 			return ret;
823 		}
824 		/* Test the hsmp interface */
825 		ret = hsmp_test(sock_ind, 0xDEADBEEF);
826 		if (ret) {
827 			dev_err(&pdev->dev, "HSMP test message failed on Fam:%x model:%x\n",
828 				boot_cpu_data.x86, boot_cpu_data.x86_model);
829 			dev_err(&pdev->dev, "Is HSMP disabled in BIOS ?\n");
830 			return ret;
831 		}
832 	} else {
833 		ret = init_platform_device(&pdev->dev);
834 		if (ret) {
835 			dev_err(&pdev->dev, "Failed to init HSMP mailbox\n");
836 			return ret;
837 		}
838 	}
839 
840 	ret = hsmp_cache_proto_ver(sock_ind);
841 	if (ret) {
842 		dev_err(&pdev->dev, "Failed to read HSMP protocol version\n");
843 		return ret;
844 	}
845 
846 	if (plat_dev.is_acpi_device)
847 		ret = hsmp_create_acpi_sysfs_if(&pdev->dev);
848 	else
849 		ret = hsmp_create_non_acpi_sysfs_if(&pdev->dev);
850 	if (ret)
851 		dev_err(&pdev->dev, "Failed to create HSMP sysfs interface\n");
852 
853 	if (!plat_dev.is_probed) {
854 		plat_dev.hsmp_device.name	= HSMP_CDEV_NAME;
855 		plat_dev.hsmp_device.minor	= MISC_DYNAMIC_MINOR;
856 		plat_dev.hsmp_device.fops	= &hsmp_fops;
857 		plat_dev.hsmp_device.parent	= &pdev->dev;
858 		plat_dev.hsmp_device.nodename	= HSMP_DEVNODE_NAME;
859 		plat_dev.hsmp_device.mode	= 0644;
860 
861 		ret = misc_register(&plat_dev.hsmp_device);
862 		if (ret)
863 			return ret;
864 
865 		plat_dev.is_probed = true;
866 	}
867 
868 	return 0;
869 
870 }
871 
872 static void hsmp_pltdrv_remove(struct platform_device *pdev)
873 {
874 	/*
875 	 * We register only one misc_device even on multi socket system.
876 	 * So, deregister should happen only once.
877 	 */
878 	if (plat_dev.is_probed) {
879 		misc_deregister(&plat_dev.hsmp_device);
880 		plat_dev.is_probed = false;
881 	}
882 }
883 
884 static struct platform_driver amd_hsmp_driver = {
885 	.probe		= hsmp_pltdrv_probe,
886 	.remove_new	= hsmp_pltdrv_remove,
887 	.driver		= {
888 		.name	= DRIVER_NAME,
889 		.acpi_match_table = amd_hsmp_acpi_ids,
890 	},
891 };
892 
893 static struct platform_device *amd_hsmp_platdev;
894 
895 static int hsmp_plat_dev_register(void)
896 {
897 	int ret;
898 
899 	amd_hsmp_platdev = platform_device_alloc(DRIVER_NAME, PLATFORM_DEVID_NONE);
900 	if (!amd_hsmp_platdev)
901 		return -ENOMEM;
902 
903 	ret = platform_device_add(amd_hsmp_platdev);
904 	if (ret)
905 		platform_device_put(amd_hsmp_platdev);
906 
907 	return ret;
908 }
909 
910 static int __init hsmp_plt_init(void)
911 {
912 	int ret = -ENODEV;
913 
914 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD || boot_cpu_data.x86 < 0x19) {
915 		pr_err("HSMP is not supported on Family:%x model:%x\n",
916 		       boot_cpu_data.x86, boot_cpu_data.x86_model);
917 		return ret;
918 	}
919 
920 	/*
921 	 * amd_nb_num() returns number of SMN/DF interfaces present in the system
922 	 * if we have N SMN/DF interfaces that ideally means N sockets
923 	 */
924 	plat_dev.num_sockets = amd_nb_num();
925 	if (plat_dev.num_sockets == 0 || plat_dev.num_sockets > MAX_AMD_SOCKETS)
926 		return ret;
927 
928 	ret = platform_driver_register(&amd_hsmp_driver);
929 	if (ret)
930 		return ret;
931 
932 	if (!plat_dev.is_acpi_device) {
933 		ret = hsmp_plat_dev_register();
934 		if (ret)
935 			platform_driver_unregister(&amd_hsmp_driver);
936 	}
937 
938 	return ret;
939 }
940 
941 static void __exit hsmp_plt_exit(void)
942 {
943 	platform_device_unregister(amd_hsmp_platdev);
944 	platform_driver_unregister(&amd_hsmp_driver);
945 }
946 
947 device_initcall(hsmp_plt_init);
948 module_exit(hsmp_plt_exit);
949 
950 MODULE_DESCRIPTION("AMD HSMP Platform Interface Driver");
951 MODULE_VERSION(DRIVER_VERSION);
952 MODULE_LICENSE("GPL v2");
953