xref: /linux/drivers/crypto/ccp/psp-dev.c (revision a6f37cee6e4f6fa9d61962efbcb06a032efed1ba)
1 /*
2  * AMD Platform Security Processor (PSP) interface
3  *
4  * Copyright (C) 2016-2017 Advanced Micro Devices, Inc.
5  *
6  * Author: Brijesh Singh <brijesh.singh@amd.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/kthread.h>
16 #include <linux/sched.h>
17 #include <linux/interrupt.h>
18 #include <linux/spinlock.h>
19 #include <linux/spinlock_types.h>
20 #include <linux/types.h>
21 #include <linux/mutex.h>
22 #include <linux/delay.h>
23 #include <linux/hw_random.h>
24 #include <linux/ccp.h>
25 #include <linux/firmware.h>
26 
27 #include "sp-dev.h"
28 #include "psp-dev.h"
29 
30 #define SEV_VERSION_GREATER_OR_EQUAL(_maj, _min)	\
31 		((psp_master->api_major) >= _maj &&	\
32 		 (psp_master->api_minor) >= _min)
33 
34 #define DEVICE_NAME		"sev"
35 #define SEV_FW_FILE		"amd/sev.fw"
36 #define SEV_FW_NAME_SIZE	64
37 
38 static DEFINE_MUTEX(sev_cmd_mutex);
39 static struct sev_misc_dev *misc_dev;
40 static struct psp_device *psp_master;
41 
42 static int psp_cmd_timeout = 100;
43 module_param(psp_cmd_timeout, int, 0644);
44 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
45 
46 static int psp_probe_timeout = 5;
47 module_param(psp_probe_timeout, int, 0644);
48 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
49 
50 static bool psp_dead;
51 static int psp_timeout;
52 
53 static struct psp_device *psp_alloc_struct(struct sp_device *sp)
54 {
55 	struct device *dev = sp->dev;
56 	struct psp_device *psp;
57 
58 	psp = devm_kzalloc(dev, sizeof(*psp), GFP_KERNEL);
59 	if (!psp)
60 		return NULL;
61 
62 	psp->dev = dev;
63 	psp->sp = sp;
64 
65 	snprintf(psp->name, sizeof(psp->name), "psp-%u", sp->ord);
66 
67 	return psp;
68 }
69 
70 static irqreturn_t psp_irq_handler(int irq, void *data)
71 {
72 	struct psp_device *psp = data;
73 	unsigned int status;
74 	int reg;
75 
76 	/* Read the interrupt status: */
77 	status = ioread32(psp->io_regs + psp->vdata->intsts_reg);
78 
79 	/* Check if it is command completion: */
80 	if (!(status & PSP_CMD_COMPLETE))
81 		goto done;
82 
83 	/* Check if it is SEV command completion: */
84 	reg = ioread32(psp->io_regs + psp->vdata->cmdresp_reg);
85 	if (reg & PSP_CMDRESP_RESP) {
86 		psp->sev_int_rcvd = 1;
87 		wake_up(&psp->sev_int_queue);
88 	}
89 
90 done:
91 	/* Clear the interrupt status by writing the same value we read. */
92 	iowrite32(status, psp->io_regs + psp->vdata->intsts_reg);
93 
94 	return IRQ_HANDLED;
95 }
96 
97 static int sev_wait_cmd_ioc(struct psp_device *psp,
98 			    unsigned int *reg, unsigned int timeout)
99 {
100 	int ret;
101 
102 	ret = wait_event_timeout(psp->sev_int_queue,
103 			psp->sev_int_rcvd, timeout * HZ);
104 	if (!ret)
105 		return -ETIMEDOUT;
106 
107 	*reg = ioread32(psp->io_regs + psp->vdata->cmdresp_reg);
108 
109 	return 0;
110 }
111 
112 static int sev_cmd_buffer_len(int cmd)
113 {
114 	switch (cmd) {
115 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
116 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
117 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
118 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
119 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
120 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
121 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
122 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
123 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
124 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
125 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
126 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
127 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
128 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
129 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
130 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
131 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
132 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
133 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
134 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
135 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
136 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
137 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
138 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
139 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
140 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
141 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
142 	default:				return 0;
143 	}
144 
145 	return 0;
146 }
147 
148 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
149 {
150 	struct psp_device *psp = psp_master;
151 	unsigned int phys_lsb, phys_msb;
152 	unsigned int reg, ret = 0;
153 
154 	if (!psp)
155 		return -ENODEV;
156 
157 	if (psp_dead)
158 		return -EBUSY;
159 
160 	/* Get the physical address of the command buffer */
161 	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
162 	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
163 
164 	dev_dbg(psp->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
165 		cmd, phys_msb, phys_lsb, psp_timeout);
166 
167 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
168 			     sev_cmd_buffer_len(cmd), false);
169 
170 	iowrite32(phys_lsb, psp->io_regs + psp->vdata->cmdbuff_addr_lo_reg);
171 	iowrite32(phys_msb, psp->io_regs + psp->vdata->cmdbuff_addr_hi_reg);
172 
173 	psp->sev_int_rcvd = 0;
174 
175 	reg = cmd;
176 	reg <<= PSP_CMDRESP_CMD_SHIFT;
177 	reg |= PSP_CMDRESP_IOC;
178 	iowrite32(reg, psp->io_regs + psp->vdata->cmdresp_reg);
179 
180 	/* wait for command completion */
181 	ret = sev_wait_cmd_ioc(psp, &reg, psp_timeout);
182 	if (ret) {
183 		if (psp_ret)
184 			*psp_ret = 0;
185 
186 		dev_err(psp->dev, "sev command %#x timed out, disabling PSP \n", cmd);
187 		psp_dead = true;
188 
189 		return ret;
190 	}
191 
192 	psp_timeout = psp_cmd_timeout;
193 
194 	if (psp_ret)
195 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
196 
197 	if (reg & PSP_CMDRESP_ERR_MASK) {
198 		dev_dbg(psp->dev, "sev command %#x failed (%#010x)\n",
199 			cmd, reg & PSP_CMDRESP_ERR_MASK);
200 		ret = -EIO;
201 	}
202 
203 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
204 			     sev_cmd_buffer_len(cmd), false);
205 
206 	return ret;
207 }
208 
209 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
210 {
211 	int rc;
212 
213 	mutex_lock(&sev_cmd_mutex);
214 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
215 	mutex_unlock(&sev_cmd_mutex);
216 
217 	return rc;
218 }
219 
220 static int __sev_platform_init_locked(int *error)
221 {
222 	struct psp_device *psp = psp_master;
223 	int rc = 0;
224 
225 	if (!psp)
226 		return -ENODEV;
227 
228 	if (psp->sev_state == SEV_STATE_INIT)
229 		return 0;
230 
231 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &psp->init_cmd_buf, error);
232 	if (rc)
233 		return rc;
234 
235 	psp->sev_state = SEV_STATE_INIT;
236 	dev_dbg(psp->dev, "SEV firmware initialized\n");
237 
238 	return rc;
239 }
240 
241 int sev_platform_init(int *error)
242 {
243 	int rc;
244 
245 	mutex_lock(&sev_cmd_mutex);
246 	rc = __sev_platform_init_locked(error);
247 	mutex_unlock(&sev_cmd_mutex);
248 
249 	return rc;
250 }
251 EXPORT_SYMBOL_GPL(sev_platform_init);
252 
253 static int __sev_platform_shutdown_locked(int *error)
254 {
255 	int ret;
256 
257 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
258 	if (ret)
259 		return ret;
260 
261 	psp_master->sev_state = SEV_STATE_UNINIT;
262 	dev_dbg(psp_master->dev, "SEV firmware shutdown\n");
263 
264 	return ret;
265 }
266 
267 static int sev_platform_shutdown(int *error)
268 {
269 	int rc;
270 
271 	mutex_lock(&sev_cmd_mutex);
272 	rc = __sev_platform_shutdown_locked(NULL);
273 	mutex_unlock(&sev_cmd_mutex);
274 
275 	return rc;
276 }
277 
278 static int sev_get_platform_state(int *state, int *error)
279 {
280 	int rc;
281 
282 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
283 				 &psp_master->status_cmd_buf, error);
284 	if (rc)
285 		return rc;
286 
287 	*state = psp_master->status_cmd_buf.state;
288 	return rc;
289 }
290 
291 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
292 {
293 	int state, rc;
294 
295 	/*
296 	 * The SEV spec requires that FACTORY_RESET must be issued in
297 	 * UNINIT state. Before we go further lets check if any guest is
298 	 * active.
299 	 *
300 	 * If FW is in WORKING state then deny the request otherwise issue
301 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
302 	 *
303 	 */
304 	rc = sev_get_platform_state(&state, &argp->error);
305 	if (rc)
306 		return rc;
307 
308 	if (state == SEV_STATE_WORKING)
309 		return -EBUSY;
310 
311 	if (state == SEV_STATE_INIT) {
312 		rc = __sev_platform_shutdown_locked(&argp->error);
313 		if (rc)
314 			return rc;
315 	}
316 
317 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
318 }
319 
320 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
321 {
322 	struct sev_user_data_status *data = &psp_master->status_cmd_buf;
323 	int ret;
324 
325 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
326 	if (ret)
327 		return ret;
328 
329 	if (copy_to_user((void __user *)argp->data, data, sizeof(*data)))
330 		ret = -EFAULT;
331 
332 	return ret;
333 }
334 
335 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp)
336 {
337 	int rc;
338 
339 	if (psp_master->sev_state == SEV_STATE_UNINIT) {
340 		rc = __sev_platform_init_locked(&argp->error);
341 		if (rc)
342 			return rc;
343 	}
344 
345 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
346 }
347 
348 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp)
349 {
350 	struct sev_user_data_pek_csr input;
351 	struct sev_data_pek_csr *data;
352 	void *blob = NULL;
353 	int ret;
354 
355 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
356 		return -EFAULT;
357 
358 	data = kzalloc(sizeof(*data), GFP_KERNEL);
359 	if (!data)
360 		return -ENOMEM;
361 
362 	/* userspace wants to query CSR length */
363 	if (!input.address || !input.length)
364 		goto cmd;
365 
366 	/* allocate a physically contiguous buffer to store the CSR blob */
367 	if (!access_ok(VERIFY_WRITE, input.address, input.length) ||
368 	    input.length > SEV_FW_BLOB_MAX_SIZE) {
369 		ret = -EFAULT;
370 		goto e_free;
371 	}
372 
373 	blob = kmalloc(input.length, GFP_KERNEL);
374 	if (!blob) {
375 		ret = -ENOMEM;
376 		goto e_free;
377 	}
378 
379 	data->address = __psp_pa(blob);
380 	data->len = input.length;
381 
382 cmd:
383 	if (psp_master->sev_state == SEV_STATE_UNINIT) {
384 		ret = __sev_platform_init_locked(&argp->error);
385 		if (ret)
386 			goto e_free_blob;
387 	}
388 
389 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
390 
391 	 /* If we query the CSR length, FW responded with expected data. */
392 	input.length = data->len;
393 
394 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
395 		ret = -EFAULT;
396 		goto e_free_blob;
397 	}
398 
399 	if (blob) {
400 		if (copy_to_user((void __user *)input.address, blob, input.length))
401 			ret = -EFAULT;
402 	}
403 
404 e_free_blob:
405 	kfree(blob);
406 e_free:
407 	kfree(data);
408 	return ret;
409 }
410 
411 void *psp_copy_user_blob(u64 __user uaddr, u32 len)
412 {
413 	if (!uaddr || !len)
414 		return ERR_PTR(-EINVAL);
415 
416 	/* verify that blob length does not exceed our limit */
417 	if (len > SEV_FW_BLOB_MAX_SIZE)
418 		return ERR_PTR(-EINVAL);
419 
420 	return memdup_user((void __user *)(uintptr_t)uaddr, len);
421 }
422 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
423 
424 static int sev_get_api_version(void)
425 {
426 	struct sev_user_data_status *status;
427 	int error = 0, ret;
428 
429 	status = &psp_master->status_cmd_buf;
430 	ret = sev_platform_status(status, &error);
431 	if (ret) {
432 		dev_err(psp_master->dev,
433 			"SEV: failed to get status. Error: %#x\n", error);
434 		return 1;
435 	}
436 
437 	psp_master->api_major = status->api_major;
438 	psp_master->api_minor = status->api_minor;
439 	psp_master->build = status->build;
440 
441 	return 0;
442 }
443 
444 int sev_get_firmware(struct device *dev, const struct firmware **firmware)
445 {
446 	char fw_name_specific[SEV_FW_NAME_SIZE];
447 	char fw_name_subset[SEV_FW_NAME_SIZE];
448 
449 	snprintf(fw_name_specific, sizeof(fw_name_specific),
450 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
451 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
452 
453 	snprintf(fw_name_subset, sizeof(fw_name_subset),
454 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
455 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
456 
457 	/* Check for SEV FW for a particular model.
458 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
459 	 *
460 	 * or
461 	 *
462 	 * Check for SEV FW common to a subset of models.
463 	 * Ex. amd_sev_fam17h_model0xh.sbin for
464 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
465 	 *
466 	 * or
467 	 *
468 	 * Fall-back to using generic name: sev.fw
469 	 */
470 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
471 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
472 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
473 		return 0;
474 
475 	return -ENOENT;
476 }
477 
478 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
479 static int sev_update_firmware(struct device *dev)
480 {
481 	struct sev_data_download_firmware *data;
482 	const struct firmware *firmware;
483 	int ret, error, order;
484 	struct page *p;
485 	u64 data_size;
486 
487 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
488 		dev_dbg(dev, "No SEV firmware file present\n");
489 		return -1;
490 	}
491 
492 	/*
493 	 * SEV FW expects the physical address given to it to be 32
494 	 * byte aligned. Memory allocated has structure placed at the
495 	 * beginning followed by the firmware being passed to the SEV
496 	 * FW. Allocate enough memory for data structure + alignment
497 	 * padding + SEV FW.
498 	 */
499 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
500 
501 	order = get_order(firmware->size + data_size);
502 	p = alloc_pages(GFP_KERNEL, order);
503 	if (!p) {
504 		ret = -1;
505 		goto fw_err;
506 	}
507 
508 	/*
509 	 * Copy firmware data to a kernel allocated contiguous
510 	 * memory region.
511 	 */
512 	data = page_address(p);
513 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
514 
515 	data->address = __psp_pa(page_address(p) + data_size);
516 	data->len = firmware->size;
517 
518 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
519 	if (ret)
520 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
521 	else
522 		dev_info(dev, "SEV firmware update successful\n");
523 
524 	__free_pages(p, order);
525 
526 fw_err:
527 	release_firmware(firmware);
528 
529 	return ret;
530 }
531 
532 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp)
533 {
534 	struct sev_user_data_pek_cert_import input;
535 	struct sev_data_pek_cert_import *data;
536 	void *pek_blob, *oca_blob;
537 	int ret;
538 
539 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
540 		return -EFAULT;
541 
542 	data = kzalloc(sizeof(*data), GFP_KERNEL);
543 	if (!data)
544 		return -ENOMEM;
545 
546 	/* copy PEK certificate blobs from userspace */
547 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
548 	if (IS_ERR(pek_blob)) {
549 		ret = PTR_ERR(pek_blob);
550 		goto e_free;
551 	}
552 
553 	data->pek_cert_address = __psp_pa(pek_blob);
554 	data->pek_cert_len = input.pek_cert_len;
555 
556 	/* copy PEK certificate blobs from userspace */
557 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
558 	if (IS_ERR(oca_blob)) {
559 		ret = PTR_ERR(oca_blob);
560 		goto e_free_pek;
561 	}
562 
563 	data->oca_cert_address = __psp_pa(oca_blob);
564 	data->oca_cert_len = input.oca_cert_len;
565 
566 	/* If platform is not in INIT state then transition it to INIT */
567 	if (psp_master->sev_state != SEV_STATE_INIT) {
568 		ret = __sev_platform_init_locked(&argp->error);
569 		if (ret)
570 			goto e_free_oca;
571 	}
572 
573 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
574 
575 e_free_oca:
576 	kfree(oca_blob);
577 e_free_pek:
578 	kfree(pek_blob);
579 e_free:
580 	kfree(data);
581 	return ret;
582 }
583 
584 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
585 {
586 	struct sev_data_get_id *data;
587 	u64 data_size, user_size;
588 	void *id_blob, *mem;
589 	int ret;
590 
591 	/* SEV GET_ID available from SEV API v0.16 and up */
592 	if (!SEV_VERSION_GREATER_OR_EQUAL(0, 16))
593 		return -ENOTSUPP;
594 
595 	/* SEV FW expects the buffer it fills with the ID to be
596 	 * 8-byte aligned. Memory allocated should be enough to
597 	 * hold data structure + alignment padding + memory
598 	 * where SEV FW writes the ID.
599 	 */
600 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
601 	user_size = sizeof(struct sev_user_data_get_id);
602 
603 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
604 	if (!mem)
605 		return -ENOMEM;
606 
607 	data = mem;
608 	id_blob = mem + data_size;
609 
610 	data->address = __psp_pa(id_blob);
611 	data->len = user_size;
612 
613 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
614 	if (!ret) {
615 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
616 			ret = -EFAULT;
617 	}
618 
619 	kfree(mem);
620 
621 	return ret;
622 }
623 
624 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp)
625 {
626 	struct sev_user_data_pdh_cert_export input;
627 	void *pdh_blob = NULL, *cert_blob = NULL;
628 	struct sev_data_pdh_cert_export *data;
629 	int ret;
630 
631 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
632 		return -EFAULT;
633 
634 	data = kzalloc(sizeof(*data), GFP_KERNEL);
635 	if (!data)
636 		return -ENOMEM;
637 
638 	/* Userspace wants to query the certificate length. */
639 	if (!input.pdh_cert_address ||
640 	    !input.pdh_cert_len ||
641 	    !input.cert_chain_address)
642 		goto cmd;
643 
644 	/* Allocate a physically contiguous buffer to store the PDH blob. */
645 	if ((input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) ||
646 	    !access_ok(VERIFY_WRITE, input.pdh_cert_address, input.pdh_cert_len)) {
647 		ret = -EFAULT;
648 		goto e_free;
649 	}
650 
651 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
652 	if ((input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) ||
653 	    !access_ok(VERIFY_WRITE, input.cert_chain_address, input.cert_chain_len)) {
654 		ret = -EFAULT;
655 		goto e_free;
656 	}
657 
658 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
659 	if (!pdh_blob) {
660 		ret = -ENOMEM;
661 		goto e_free;
662 	}
663 
664 	data->pdh_cert_address = __psp_pa(pdh_blob);
665 	data->pdh_cert_len = input.pdh_cert_len;
666 
667 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
668 	if (!cert_blob) {
669 		ret = -ENOMEM;
670 		goto e_free_pdh;
671 	}
672 
673 	data->cert_chain_address = __psp_pa(cert_blob);
674 	data->cert_chain_len = input.cert_chain_len;
675 
676 cmd:
677 	/* If platform is not in INIT state then transition it to INIT. */
678 	if (psp_master->sev_state != SEV_STATE_INIT) {
679 		ret = __sev_platform_init_locked(&argp->error);
680 		if (ret)
681 			goto e_free_cert;
682 	}
683 
684 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
685 
686 	/* If we query the length, FW responded with expected data. */
687 	input.cert_chain_len = data->cert_chain_len;
688 	input.pdh_cert_len = data->pdh_cert_len;
689 
690 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
691 		ret = -EFAULT;
692 		goto e_free_cert;
693 	}
694 
695 	if (pdh_blob) {
696 		if (copy_to_user((void __user *)input.pdh_cert_address,
697 				 pdh_blob, input.pdh_cert_len)) {
698 			ret = -EFAULT;
699 			goto e_free_cert;
700 		}
701 	}
702 
703 	if (cert_blob) {
704 		if (copy_to_user((void __user *)input.cert_chain_address,
705 				 cert_blob, input.cert_chain_len))
706 			ret = -EFAULT;
707 	}
708 
709 e_free_cert:
710 	kfree(cert_blob);
711 e_free_pdh:
712 	kfree(pdh_blob);
713 e_free:
714 	kfree(data);
715 	return ret;
716 }
717 
718 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
719 {
720 	void __user *argp = (void __user *)arg;
721 	struct sev_issue_cmd input;
722 	int ret = -EFAULT;
723 
724 	if (!psp_master)
725 		return -ENODEV;
726 
727 	if (ioctl != SEV_ISSUE_CMD)
728 		return -EINVAL;
729 
730 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
731 		return -EFAULT;
732 
733 	if (input.cmd > SEV_MAX)
734 		return -EINVAL;
735 
736 	mutex_lock(&sev_cmd_mutex);
737 
738 	switch (input.cmd) {
739 
740 	case SEV_FACTORY_RESET:
741 		ret = sev_ioctl_do_reset(&input);
742 		break;
743 	case SEV_PLATFORM_STATUS:
744 		ret = sev_ioctl_do_platform_status(&input);
745 		break;
746 	case SEV_PEK_GEN:
747 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input);
748 		break;
749 	case SEV_PDH_GEN:
750 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input);
751 		break;
752 	case SEV_PEK_CSR:
753 		ret = sev_ioctl_do_pek_csr(&input);
754 		break;
755 	case SEV_PEK_CERT_IMPORT:
756 		ret = sev_ioctl_do_pek_import(&input);
757 		break;
758 	case SEV_PDH_CERT_EXPORT:
759 		ret = sev_ioctl_do_pdh_export(&input);
760 		break;
761 	case SEV_GET_ID:
762 		ret = sev_ioctl_do_get_id(&input);
763 		break;
764 	default:
765 		ret = -EINVAL;
766 		goto out;
767 	}
768 
769 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
770 		ret = -EFAULT;
771 out:
772 	mutex_unlock(&sev_cmd_mutex);
773 
774 	return ret;
775 }
776 
777 static const struct file_operations sev_fops = {
778 	.owner	= THIS_MODULE,
779 	.unlocked_ioctl = sev_ioctl,
780 };
781 
782 int sev_platform_status(struct sev_user_data_status *data, int *error)
783 {
784 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
785 }
786 EXPORT_SYMBOL_GPL(sev_platform_status);
787 
788 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
789 {
790 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
791 }
792 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
793 
794 int sev_guest_activate(struct sev_data_activate *data, int *error)
795 {
796 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
797 }
798 EXPORT_SYMBOL_GPL(sev_guest_activate);
799 
800 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
801 {
802 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
803 }
804 EXPORT_SYMBOL_GPL(sev_guest_decommission);
805 
806 int sev_guest_df_flush(int *error)
807 {
808 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
809 }
810 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
811 
812 static void sev_exit(struct kref *ref)
813 {
814 	struct sev_misc_dev *misc_dev = container_of(ref, struct sev_misc_dev, refcount);
815 
816 	misc_deregister(&misc_dev->misc);
817 }
818 
819 static int sev_misc_init(struct psp_device *psp)
820 {
821 	struct device *dev = psp->dev;
822 	int ret;
823 
824 	/*
825 	 * SEV feature support can be detected on multiple devices but the SEV
826 	 * FW commands must be issued on the master. During probe, we do not
827 	 * know the master hence we create /dev/sev on the first device probe.
828 	 * sev_do_cmd() finds the right master device to which to issue the
829 	 * command to the firmware.
830 	 */
831 	if (!misc_dev) {
832 		struct miscdevice *misc;
833 
834 		misc_dev = devm_kzalloc(dev, sizeof(*misc_dev), GFP_KERNEL);
835 		if (!misc_dev)
836 			return -ENOMEM;
837 
838 		misc = &misc_dev->misc;
839 		misc->minor = MISC_DYNAMIC_MINOR;
840 		misc->name = DEVICE_NAME;
841 		misc->fops = &sev_fops;
842 
843 		ret = misc_register(misc);
844 		if (ret)
845 			return ret;
846 
847 		kref_init(&misc_dev->refcount);
848 	} else {
849 		kref_get(&misc_dev->refcount);
850 	}
851 
852 	init_waitqueue_head(&psp->sev_int_queue);
853 	psp->sev_misc = misc_dev;
854 	dev_dbg(dev, "registered SEV device\n");
855 
856 	return 0;
857 }
858 
859 static int sev_init(struct psp_device *psp)
860 {
861 	/* Check if device supports SEV feature */
862 	if (!(ioread32(psp->io_regs + psp->vdata->feature_reg) & 1)) {
863 		dev_dbg(psp->dev, "device does not support SEV\n");
864 		return 1;
865 	}
866 
867 	return sev_misc_init(psp);
868 }
869 
870 int psp_dev_init(struct sp_device *sp)
871 {
872 	struct device *dev = sp->dev;
873 	struct psp_device *psp;
874 	int ret;
875 
876 	ret = -ENOMEM;
877 	psp = psp_alloc_struct(sp);
878 	if (!psp)
879 		goto e_err;
880 
881 	sp->psp_data = psp;
882 
883 	psp->vdata = (struct psp_vdata *)sp->dev_vdata->psp_vdata;
884 	if (!psp->vdata) {
885 		ret = -ENODEV;
886 		dev_err(dev, "missing driver data\n");
887 		goto e_err;
888 	}
889 
890 	psp->io_regs = sp->io_map;
891 
892 	/* Disable and clear interrupts until ready */
893 	iowrite32(0, psp->io_regs + psp->vdata->inten_reg);
894 	iowrite32(-1, psp->io_regs + psp->vdata->intsts_reg);
895 
896 	/* Request an irq */
897 	ret = sp_request_psp_irq(psp->sp, psp_irq_handler, psp->name, psp);
898 	if (ret) {
899 		dev_err(dev, "psp: unable to allocate an IRQ\n");
900 		goto e_err;
901 	}
902 
903 	ret = sev_init(psp);
904 	if (ret)
905 		goto e_irq;
906 
907 	if (sp->set_psp_master_device)
908 		sp->set_psp_master_device(sp);
909 
910 	/* Enable interrupt */
911 	iowrite32(-1, psp->io_regs + psp->vdata->inten_reg);
912 
913 	dev_notice(dev, "psp enabled\n");
914 
915 	return 0;
916 
917 e_irq:
918 	sp_free_psp_irq(psp->sp, psp);
919 e_err:
920 	sp->psp_data = NULL;
921 
922 	dev_notice(dev, "psp initialization failed\n");
923 
924 	return ret;
925 }
926 
927 void psp_dev_destroy(struct sp_device *sp)
928 {
929 	struct psp_device *psp = sp->psp_data;
930 
931 	if (!psp)
932 		return;
933 
934 	if (psp->sev_misc)
935 		kref_put(&misc_dev->refcount, sev_exit);
936 
937 	sp_free_psp_irq(sp, psp);
938 }
939 
940 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
941 				void *data, int *error)
942 {
943 	if (!filep || filep->f_op != &sev_fops)
944 		return -EBADF;
945 
946 	return  sev_do_cmd(cmd, data, error);
947 }
948 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
949 
950 void psp_pci_init(void)
951 {
952 	struct sp_device *sp;
953 	int error, rc;
954 
955 	sp = sp_get_psp_master_device();
956 	if (!sp)
957 		return;
958 
959 	psp_master = sp->psp_data;
960 
961 	psp_timeout = psp_probe_timeout;
962 
963 	if (sev_get_api_version())
964 		goto err;
965 
966 	if (SEV_VERSION_GREATER_OR_EQUAL(0, 15) &&
967 	    sev_update_firmware(psp_master->dev) == 0)
968 		sev_get_api_version();
969 
970 	/* Initialize the platform */
971 	rc = sev_platform_init(&error);
972 	if (rc) {
973 		dev_err(sp->dev, "SEV: failed to INIT error %#x\n", error);
974 		goto err;
975 	}
976 
977 	dev_info(sp->dev, "SEV API:%d.%d build:%d\n", psp_master->api_major,
978 		 psp_master->api_minor, psp_master->build);
979 
980 	return;
981 
982 err:
983 	psp_master = NULL;
984 }
985 
986 void psp_pci_exit(void)
987 {
988 	if (!psp_master)
989 		return;
990 
991 	sev_platform_shutdown(NULL);
992 }
993