xref: /openbmc/linux/drivers/crypto/ccp/psp-dev.c (revision 6f69e2a3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Platform Security Processor (PSP) interface
4  *
5  * Copyright (C) 2016,2018 Advanced Micro Devices, Inc.
6  *
7  * Author: Brijesh Singh <brijesh.singh@amd.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/kthread.h>
13 #include <linux/sched.h>
14 #include <linux/interrupt.h>
15 #include <linux/spinlock.h>
16 #include <linux/spinlock_types.h>
17 #include <linux/types.h>
18 #include <linux/mutex.h>
19 #include <linux/delay.h>
20 #include <linux/hw_random.h>
21 #include <linux/ccp.h>
22 #include <linux/firmware.h>
23 
24 #include <asm/smp.h>
25 
26 #include "sp-dev.h"
27 #include "psp-dev.h"
28 
29 #define DEVICE_NAME		"sev"
30 #define SEV_FW_FILE		"amd/sev.fw"
31 #define SEV_FW_NAME_SIZE	64
32 
33 static DEFINE_MUTEX(sev_cmd_mutex);
34 static struct sev_misc_dev *misc_dev;
35 static struct psp_device *psp_master;
36 
37 static int psp_cmd_timeout = 100;
38 module_param(psp_cmd_timeout, int, 0644);
39 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
40 
41 static int psp_probe_timeout = 5;
42 module_param(psp_probe_timeout, int, 0644);
43 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
44 
45 static bool psp_dead;
46 static int psp_timeout;
47 
48 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
49 {
50 	if (psp_master->api_major > maj)
51 		return true;
52 	if (psp_master->api_major == maj && psp_master->api_minor >= min)
53 		return true;
54 	return false;
55 }
56 
57 static struct psp_device *psp_alloc_struct(struct sp_device *sp)
58 {
59 	struct device *dev = sp->dev;
60 	struct psp_device *psp;
61 
62 	psp = devm_kzalloc(dev, sizeof(*psp), GFP_KERNEL);
63 	if (!psp)
64 		return NULL;
65 
66 	psp->dev = dev;
67 	psp->sp = sp;
68 
69 	snprintf(psp->name, sizeof(psp->name), "psp-%u", sp->ord);
70 
71 	return psp;
72 }
73 
74 static irqreturn_t psp_irq_handler(int irq, void *data)
75 {
76 	struct psp_device *psp = data;
77 	unsigned int status;
78 	int reg;
79 
80 	/* Read the interrupt status: */
81 	status = ioread32(psp->io_regs + psp->vdata->intsts_reg);
82 
83 	/* Check if it is command completion: */
84 	if (!(status & PSP_CMD_COMPLETE))
85 		goto done;
86 
87 	/* Check if it is SEV command completion: */
88 	reg = ioread32(psp->io_regs + psp->vdata->cmdresp_reg);
89 	if (reg & PSP_CMDRESP_RESP) {
90 		psp->sev_int_rcvd = 1;
91 		wake_up(&psp->sev_int_queue);
92 	}
93 
94 done:
95 	/* Clear the interrupt status by writing the same value we read. */
96 	iowrite32(status, psp->io_regs + psp->vdata->intsts_reg);
97 
98 	return IRQ_HANDLED;
99 }
100 
101 static int sev_wait_cmd_ioc(struct psp_device *psp,
102 			    unsigned int *reg, unsigned int timeout)
103 {
104 	int ret;
105 
106 	ret = wait_event_timeout(psp->sev_int_queue,
107 			psp->sev_int_rcvd, timeout * HZ);
108 	if (!ret)
109 		return -ETIMEDOUT;
110 
111 	*reg = ioread32(psp->io_regs + psp->vdata->cmdresp_reg);
112 
113 	return 0;
114 }
115 
116 static int sev_cmd_buffer_len(int cmd)
117 {
118 	switch (cmd) {
119 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
120 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
121 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
122 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
123 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
124 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
125 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
126 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
127 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
128 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
129 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
130 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
131 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
132 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
133 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
134 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
135 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
136 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
137 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
138 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
139 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
140 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
141 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
142 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
143 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
144 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
145 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
146 	default:				return 0;
147 	}
148 
149 	return 0;
150 }
151 
152 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
153 {
154 	struct psp_device *psp = psp_master;
155 	unsigned int phys_lsb, phys_msb;
156 	unsigned int reg, ret = 0;
157 
158 	if (!psp)
159 		return -ENODEV;
160 
161 	if (psp_dead)
162 		return -EBUSY;
163 
164 	/* Get the physical address of the command buffer */
165 	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
166 	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
167 
168 	dev_dbg(psp->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
169 		cmd, phys_msb, phys_lsb, psp_timeout);
170 
171 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
172 			     sev_cmd_buffer_len(cmd), false);
173 
174 	iowrite32(phys_lsb, psp->io_regs + psp->vdata->cmdbuff_addr_lo_reg);
175 	iowrite32(phys_msb, psp->io_regs + psp->vdata->cmdbuff_addr_hi_reg);
176 
177 	psp->sev_int_rcvd = 0;
178 
179 	reg = cmd;
180 	reg <<= PSP_CMDRESP_CMD_SHIFT;
181 	reg |= PSP_CMDRESP_IOC;
182 	iowrite32(reg, psp->io_regs + psp->vdata->cmdresp_reg);
183 
184 	/* wait for command completion */
185 	ret = sev_wait_cmd_ioc(psp, &reg, psp_timeout);
186 	if (ret) {
187 		if (psp_ret)
188 			*psp_ret = 0;
189 
190 		dev_err(psp->dev, "sev command %#x timed out, disabling PSP \n", cmd);
191 		psp_dead = true;
192 
193 		return ret;
194 	}
195 
196 	psp_timeout = psp_cmd_timeout;
197 
198 	if (psp_ret)
199 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
200 
201 	if (reg & PSP_CMDRESP_ERR_MASK) {
202 		dev_dbg(psp->dev, "sev command %#x failed (%#010x)\n",
203 			cmd, reg & PSP_CMDRESP_ERR_MASK);
204 		ret = -EIO;
205 	}
206 
207 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
208 			     sev_cmd_buffer_len(cmd), false);
209 
210 	return ret;
211 }
212 
213 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
214 {
215 	int rc;
216 
217 	mutex_lock(&sev_cmd_mutex);
218 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
219 	mutex_unlock(&sev_cmd_mutex);
220 
221 	return rc;
222 }
223 
224 static int __sev_platform_init_locked(int *error)
225 {
226 	struct psp_device *psp = psp_master;
227 	int rc = 0;
228 
229 	if (!psp)
230 		return -ENODEV;
231 
232 	if (psp->sev_state == SEV_STATE_INIT)
233 		return 0;
234 
235 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &psp->init_cmd_buf, error);
236 	if (rc)
237 		return rc;
238 
239 	psp->sev_state = SEV_STATE_INIT;
240 
241 	/* Prepare for first SEV guest launch after INIT */
242 	wbinvd_on_all_cpus();
243 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
244 	if (rc)
245 		return rc;
246 
247 	dev_dbg(psp->dev, "SEV firmware initialized\n");
248 
249 	return rc;
250 }
251 
252 int sev_platform_init(int *error)
253 {
254 	int rc;
255 
256 	mutex_lock(&sev_cmd_mutex);
257 	rc = __sev_platform_init_locked(error);
258 	mutex_unlock(&sev_cmd_mutex);
259 
260 	return rc;
261 }
262 EXPORT_SYMBOL_GPL(sev_platform_init);
263 
264 static int __sev_platform_shutdown_locked(int *error)
265 {
266 	int ret;
267 
268 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
269 	if (ret)
270 		return ret;
271 
272 	psp_master->sev_state = SEV_STATE_UNINIT;
273 	dev_dbg(psp_master->dev, "SEV firmware shutdown\n");
274 
275 	return ret;
276 }
277 
278 static int sev_platform_shutdown(int *error)
279 {
280 	int rc;
281 
282 	mutex_lock(&sev_cmd_mutex);
283 	rc = __sev_platform_shutdown_locked(NULL);
284 	mutex_unlock(&sev_cmd_mutex);
285 
286 	return rc;
287 }
288 
289 static int sev_get_platform_state(int *state, int *error)
290 {
291 	int rc;
292 
293 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
294 				 &psp_master->status_cmd_buf, error);
295 	if (rc)
296 		return rc;
297 
298 	*state = psp_master->status_cmd_buf.state;
299 	return rc;
300 }
301 
302 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
303 {
304 	int state, rc;
305 
306 	if (!capable(CAP_SYS_ADMIN))
307 		return -EPERM;
308 
309 	/*
310 	 * The SEV spec requires that FACTORY_RESET must be issued in
311 	 * UNINIT state. Before we go further lets check if any guest is
312 	 * active.
313 	 *
314 	 * If FW is in WORKING state then deny the request otherwise issue
315 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
316 	 *
317 	 */
318 	rc = sev_get_platform_state(&state, &argp->error);
319 	if (rc)
320 		return rc;
321 
322 	if (state == SEV_STATE_WORKING)
323 		return -EBUSY;
324 
325 	if (state == SEV_STATE_INIT) {
326 		rc = __sev_platform_shutdown_locked(&argp->error);
327 		if (rc)
328 			return rc;
329 	}
330 
331 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
332 }
333 
334 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
335 {
336 	struct sev_user_data_status *data = &psp_master->status_cmd_buf;
337 	int ret;
338 
339 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
340 	if (ret)
341 		return ret;
342 
343 	if (copy_to_user((void __user *)argp->data, data, sizeof(*data)))
344 		ret = -EFAULT;
345 
346 	return ret;
347 }
348 
349 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp)
350 {
351 	int rc;
352 
353 	if (!capable(CAP_SYS_ADMIN))
354 		return -EPERM;
355 
356 	if (psp_master->sev_state == SEV_STATE_UNINIT) {
357 		rc = __sev_platform_init_locked(&argp->error);
358 		if (rc)
359 			return rc;
360 	}
361 
362 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
363 }
364 
365 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp)
366 {
367 	struct sev_user_data_pek_csr input;
368 	struct sev_data_pek_csr *data;
369 	void *blob = NULL;
370 	int ret;
371 
372 	if (!capable(CAP_SYS_ADMIN))
373 		return -EPERM;
374 
375 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
376 		return -EFAULT;
377 
378 	data = kzalloc(sizeof(*data), GFP_KERNEL);
379 	if (!data)
380 		return -ENOMEM;
381 
382 	/* userspace wants to query CSR length */
383 	if (!input.address || !input.length)
384 		goto cmd;
385 
386 	/* allocate a physically contiguous buffer to store the CSR blob */
387 	if (!access_ok(input.address, input.length) ||
388 	    input.length > SEV_FW_BLOB_MAX_SIZE) {
389 		ret = -EFAULT;
390 		goto e_free;
391 	}
392 
393 	blob = kmalloc(input.length, GFP_KERNEL);
394 	if (!blob) {
395 		ret = -ENOMEM;
396 		goto e_free;
397 	}
398 
399 	data->address = __psp_pa(blob);
400 	data->len = input.length;
401 
402 cmd:
403 	if (psp_master->sev_state == SEV_STATE_UNINIT) {
404 		ret = __sev_platform_init_locked(&argp->error);
405 		if (ret)
406 			goto e_free_blob;
407 	}
408 
409 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
410 
411 	 /* If we query the CSR length, FW responded with expected data. */
412 	input.length = data->len;
413 
414 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
415 		ret = -EFAULT;
416 		goto e_free_blob;
417 	}
418 
419 	if (blob) {
420 		if (copy_to_user((void __user *)input.address, blob, input.length))
421 			ret = -EFAULT;
422 	}
423 
424 e_free_blob:
425 	kfree(blob);
426 e_free:
427 	kfree(data);
428 	return ret;
429 }
430 
431 void *psp_copy_user_blob(u64 __user uaddr, u32 len)
432 {
433 	if (!uaddr || !len)
434 		return ERR_PTR(-EINVAL);
435 
436 	/* verify that blob length does not exceed our limit */
437 	if (len > SEV_FW_BLOB_MAX_SIZE)
438 		return ERR_PTR(-EINVAL);
439 
440 	return memdup_user((void __user *)(uintptr_t)uaddr, len);
441 }
442 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
443 
444 static int sev_get_api_version(void)
445 {
446 	struct sev_user_data_status *status;
447 	int error = 0, ret;
448 
449 	status = &psp_master->status_cmd_buf;
450 	ret = sev_platform_status(status, &error);
451 	if (ret) {
452 		dev_err(psp_master->dev,
453 			"SEV: failed to get status. Error: %#x\n", error);
454 		return 1;
455 	}
456 
457 	psp_master->api_major = status->api_major;
458 	psp_master->api_minor = status->api_minor;
459 	psp_master->build = status->build;
460 	psp_master->sev_state = status->state;
461 
462 	return 0;
463 }
464 
465 static int sev_get_firmware(struct device *dev,
466 			    const struct firmware **firmware)
467 {
468 	char fw_name_specific[SEV_FW_NAME_SIZE];
469 	char fw_name_subset[SEV_FW_NAME_SIZE];
470 
471 	snprintf(fw_name_specific, sizeof(fw_name_specific),
472 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
473 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
474 
475 	snprintf(fw_name_subset, sizeof(fw_name_subset),
476 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
477 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
478 
479 	/* Check for SEV FW for a particular model.
480 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
481 	 *
482 	 * or
483 	 *
484 	 * Check for SEV FW common to a subset of models.
485 	 * Ex. amd_sev_fam17h_model0xh.sbin for
486 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
487 	 *
488 	 * or
489 	 *
490 	 * Fall-back to using generic name: sev.fw
491 	 */
492 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
493 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
494 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
495 		return 0;
496 
497 	return -ENOENT;
498 }
499 
500 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
501 static int sev_update_firmware(struct device *dev)
502 {
503 	struct sev_data_download_firmware *data;
504 	const struct firmware *firmware;
505 	int ret, error, order;
506 	struct page *p;
507 	u64 data_size;
508 
509 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
510 		dev_dbg(dev, "No SEV firmware file present\n");
511 		return -1;
512 	}
513 
514 	/*
515 	 * SEV FW expects the physical address given to it to be 32
516 	 * byte aligned. Memory allocated has structure placed at the
517 	 * beginning followed by the firmware being passed to the SEV
518 	 * FW. Allocate enough memory for data structure + alignment
519 	 * padding + SEV FW.
520 	 */
521 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
522 
523 	order = get_order(firmware->size + data_size);
524 	p = alloc_pages(GFP_KERNEL, order);
525 	if (!p) {
526 		ret = -1;
527 		goto fw_err;
528 	}
529 
530 	/*
531 	 * Copy firmware data to a kernel allocated contiguous
532 	 * memory region.
533 	 */
534 	data = page_address(p);
535 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
536 
537 	data->address = __psp_pa(page_address(p) + data_size);
538 	data->len = firmware->size;
539 
540 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
541 	if (ret)
542 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
543 	else
544 		dev_info(dev, "SEV firmware update successful\n");
545 
546 	__free_pages(p, order);
547 
548 fw_err:
549 	release_firmware(firmware);
550 
551 	return ret;
552 }
553 
554 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp)
555 {
556 	struct sev_user_data_pek_cert_import input;
557 	struct sev_data_pek_cert_import *data;
558 	void *pek_blob, *oca_blob;
559 	int ret;
560 
561 	if (!capable(CAP_SYS_ADMIN))
562 		return -EPERM;
563 
564 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
565 		return -EFAULT;
566 
567 	data = kzalloc(sizeof(*data), GFP_KERNEL);
568 	if (!data)
569 		return -ENOMEM;
570 
571 	/* copy PEK certificate blobs from userspace */
572 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
573 	if (IS_ERR(pek_blob)) {
574 		ret = PTR_ERR(pek_blob);
575 		goto e_free;
576 	}
577 
578 	data->pek_cert_address = __psp_pa(pek_blob);
579 	data->pek_cert_len = input.pek_cert_len;
580 
581 	/* copy PEK certificate blobs from userspace */
582 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
583 	if (IS_ERR(oca_blob)) {
584 		ret = PTR_ERR(oca_blob);
585 		goto e_free_pek;
586 	}
587 
588 	data->oca_cert_address = __psp_pa(oca_blob);
589 	data->oca_cert_len = input.oca_cert_len;
590 
591 	/* If platform is not in INIT state then transition it to INIT */
592 	if (psp_master->sev_state != SEV_STATE_INIT) {
593 		ret = __sev_platform_init_locked(&argp->error);
594 		if (ret)
595 			goto e_free_oca;
596 	}
597 
598 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
599 
600 e_free_oca:
601 	kfree(oca_blob);
602 e_free_pek:
603 	kfree(pek_blob);
604 e_free:
605 	kfree(data);
606 	return ret;
607 }
608 
609 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
610 {
611 	struct sev_user_data_get_id2 input;
612 	struct sev_data_get_id *data;
613 	void *id_blob = NULL;
614 	int ret;
615 
616 	/* SEV GET_ID is available from SEV API v0.16 and up */
617 	if (!sev_version_greater_or_equal(0, 16))
618 		return -ENOTSUPP;
619 
620 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
621 		return -EFAULT;
622 
623 	/* Check if we have write access to the userspace buffer */
624 	if (input.address &&
625 	    input.length &&
626 	    !access_ok(input.address, input.length))
627 		return -EFAULT;
628 
629 	data = kzalloc(sizeof(*data), GFP_KERNEL);
630 	if (!data)
631 		return -ENOMEM;
632 
633 	if (input.address && input.length) {
634 		id_blob = kmalloc(input.length, GFP_KERNEL);
635 		if (!id_blob) {
636 			kfree(data);
637 			return -ENOMEM;
638 		}
639 
640 		data->address = __psp_pa(id_blob);
641 		data->len = input.length;
642 	}
643 
644 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
645 
646 	/*
647 	 * Firmware will return the length of the ID value (either the minimum
648 	 * required length or the actual length written), return it to the user.
649 	 */
650 	input.length = data->len;
651 
652 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
653 		ret = -EFAULT;
654 		goto e_free;
655 	}
656 
657 	if (id_blob) {
658 		if (copy_to_user((void __user *)input.address,
659 				 id_blob, data->len)) {
660 			ret = -EFAULT;
661 			goto e_free;
662 		}
663 	}
664 
665 e_free:
666 	kfree(id_blob);
667 	kfree(data);
668 
669 	return ret;
670 }
671 
672 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
673 {
674 	struct sev_data_get_id *data;
675 	u64 data_size, user_size;
676 	void *id_blob, *mem;
677 	int ret;
678 
679 	/* SEV GET_ID available from SEV API v0.16 and up */
680 	if (!sev_version_greater_or_equal(0, 16))
681 		return -ENOTSUPP;
682 
683 	/* SEV FW expects the buffer it fills with the ID to be
684 	 * 8-byte aligned. Memory allocated should be enough to
685 	 * hold data structure + alignment padding + memory
686 	 * where SEV FW writes the ID.
687 	 */
688 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
689 	user_size = sizeof(struct sev_user_data_get_id);
690 
691 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
692 	if (!mem)
693 		return -ENOMEM;
694 
695 	data = mem;
696 	id_blob = mem + data_size;
697 
698 	data->address = __psp_pa(id_blob);
699 	data->len = user_size;
700 
701 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
702 	if (!ret) {
703 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
704 			ret = -EFAULT;
705 	}
706 
707 	kfree(mem);
708 
709 	return ret;
710 }
711 
712 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp)
713 {
714 	struct sev_user_data_pdh_cert_export input;
715 	void *pdh_blob = NULL, *cert_blob = NULL;
716 	struct sev_data_pdh_cert_export *data;
717 	int ret;
718 
719 	/* If platform is not in INIT state then transition it to INIT. */
720 	if (psp_master->sev_state != SEV_STATE_INIT) {
721 		if (!capable(CAP_SYS_ADMIN))
722 			return -EPERM;
723 
724 		ret = __sev_platform_init_locked(&argp->error);
725 		if (ret)
726 			return ret;
727 	}
728 
729 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
730 		return -EFAULT;
731 
732 	data = kzalloc(sizeof(*data), GFP_KERNEL);
733 	if (!data)
734 		return -ENOMEM;
735 
736 	/* Userspace wants to query the certificate length. */
737 	if (!input.pdh_cert_address ||
738 	    !input.pdh_cert_len ||
739 	    !input.cert_chain_address)
740 		goto cmd;
741 
742 	/* Allocate a physically contiguous buffer to store the PDH blob. */
743 	if ((input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) ||
744 	    !access_ok(input.pdh_cert_address, input.pdh_cert_len)) {
745 		ret = -EFAULT;
746 		goto e_free;
747 	}
748 
749 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
750 	if ((input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) ||
751 	    !access_ok(input.cert_chain_address, input.cert_chain_len)) {
752 		ret = -EFAULT;
753 		goto e_free;
754 	}
755 
756 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
757 	if (!pdh_blob) {
758 		ret = -ENOMEM;
759 		goto e_free;
760 	}
761 
762 	data->pdh_cert_address = __psp_pa(pdh_blob);
763 	data->pdh_cert_len = input.pdh_cert_len;
764 
765 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
766 	if (!cert_blob) {
767 		ret = -ENOMEM;
768 		goto e_free_pdh;
769 	}
770 
771 	data->cert_chain_address = __psp_pa(cert_blob);
772 	data->cert_chain_len = input.cert_chain_len;
773 
774 cmd:
775 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
776 
777 	/* If we query the length, FW responded with expected data. */
778 	input.cert_chain_len = data->cert_chain_len;
779 	input.pdh_cert_len = data->pdh_cert_len;
780 
781 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
782 		ret = -EFAULT;
783 		goto e_free_cert;
784 	}
785 
786 	if (pdh_blob) {
787 		if (copy_to_user((void __user *)input.pdh_cert_address,
788 				 pdh_blob, input.pdh_cert_len)) {
789 			ret = -EFAULT;
790 			goto e_free_cert;
791 		}
792 	}
793 
794 	if (cert_blob) {
795 		if (copy_to_user((void __user *)input.cert_chain_address,
796 				 cert_blob, input.cert_chain_len))
797 			ret = -EFAULT;
798 	}
799 
800 e_free_cert:
801 	kfree(cert_blob);
802 e_free_pdh:
803 	kfree(pdh_blob);
804 e_free:
805 	kfree(data);
806 	return ret;
807 }
808 
809 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
810 {
811 	void __user *argp = (void __user *)arg;
812 	struct sev_issue_cmd input;
813 	int ret = -EFAULT;
814 
815 	if (!psp_master)
816 		return -ENODEV;
817 
818 	if (ioctl != SEV_ISSUE_CMD)
819 		return -EINVAL;
820 
821 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
822 		return -EFAULT;
823 
824 	if (input.cmd > SEV_MAX)
825 		return -EINVAL;
826 
827 	mutex_lock(&sev_cmd_mutex);
828 
829 	switch (input.cmd) {
830 
831 	case SEV_FACTORY_RESET:
832 		ret = sev_ioctl_do_reset(&input);
833 		break;
834 	case SEV_PLATFORM_STATUS:
835 		ret = sev_ioctl_do_platform_status(&input);
836 		break;
837 	case SEV_PEK_GEN:
838 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input);
839 		break;
840 	case SEV_PDH_GEN:
841 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input);
842 		break;
843 	case SEV_PEK_CSR:
844 		ret = sev_ioctl_do_pek_csr(&input);
845 		break;
846 	case SEV_PEK_CERT_IMPORT:
847 		ret = sev_ioctl_do_pek_import(&input);
848 		break;
849 	case SEV_PDH_CERT_EXPORT:
850 		ret = sev_ioctl_do_pdh_export(&input);
851 		break;
852 	case SEV_GET_ID:
853 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
854 		ret = sev_ioctl_do_get_id(&input);
855 		break;
856 	case SEV_GET_ID2:
857 		ret = sev_ioctl_do_get_id2(&input);
858 		break;
859 	default:
860 		ret = -EINVAL;
861 		goto out;
862 	}
863 
864 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
865 		ret = -EFAULT;
866 out:
867 	mutex_unlock(&sev_cmd_mutex);
868 
869 	return ret;
870 }
871 
872 static const struct file_operations sev_fops = {
873 	.owner	= THIS_MODULE,
874 	.unlocked_ioctl = sev_ioctl,
875 };
876 
877 int sev_platform_status(struct sev_user_data_status *data, int *error)
878 {
879 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
880 }
881 EXPORT_SYMBOL_GPL(sev_platform_status);
882 
883 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
884 {
885 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
886 }
887 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
888 
889 int sev_guest_activate(struct sev_data_activate *data, int *error)
890 {
891 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
892 }
893 EXPORT_SYMBOL_GPL(sev_guest_activate);
894 
895 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
896 {
897 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
898 }
899 EXPORT_SYMBOL_GPL(sev_guest_decommission);
900 
901 int sev_guest_df_flush(int *error)
902 {
903 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
904 }
905 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
906 
907 static void sev_exit(struct kref *ref)
908 {
909 	struct sev_misc_dev *misc_dev = container_of(ref, struct sev_misc_dev, refcount);
910 
911 	misc_deregister(&misc_dev->misc);
912 }
913 
914 static int sev_misc_init(struct psp_device *psp)
915 {
916 	struct device *dev = psp->dev;
917 	int ret;
918 
919 	/*
920 	 * SEV feature support can be detected on multiple devices but the SEV
921 	 * FW commands must be issued on the master. During probe, we do not
922 	 * know the master hence we create /dev/sev on the first device probe.
923 	 * sev_do_cmd() finds the right master device to which to issue the
924 	 * command to the firmware.
925 	 */
926 	if (!misc_dev) {
927 		struct miscdevice *misc;
928 
929 		misc_dev = devm_kzalloc(dev, sizeof(*misc_dev), GFP_KERNEL);
930 		if (!misc_dev)
931 			return -ENOMEM;
932 
933 		misc = &misc_dev->misc;
934 		misc->minor = MISC_DYNAMIC_MINOR;
935 		misc->name = DEVICE_NAME;
936 		misc->fops = &sev_fops;
937 
938 		ret = misc_register(misc);
939 		if (ret)
940 			return ret;
941 
942 		kref_init(&misc_dev->refcount);
943 	} else {
944 		kref_get(&misc_dev->refcount);
945 	}
946 
947 	init_waitqueue_head(&psp->sev_int_queue);
948 	psp->sev_misc = misc_dev;
949 	dev_dbg(dev, "registered SEV device\n");
950 
951 	return 0;
952 }
953 
954 static int psp_check_sev_support(struct psp_device *psp)
955 {
956 	unsigned int val = ioread32(psp->io_regs + psp->vdata->feature_reg);
957 
958 	/*
959 	 * Check for a access to the registers.  If this read returns
960 	 * 0xffffffff, it's likely that the system is running a broken
961 	 * BIOS which disallows access to the device. Stop here and
962 	 * fail the PSP initialization (but not the load, as the CCP
963 	 * could get properly initialized).
964 	 */
965 	if (val == 0xffffffff) {
966 		dev_notice(psp->dev, "psp: unable to access the device: you might be running a broken BIOS.\n");
967 		return -ENODEV;
968 	}
969 
970 	if (!(val & 1)) {
971 		/* Device does not support the SEV feature */
972 		dev_dbg(psp->dev, "psp does not support SEV\n");
973 		return -ENODEV;
974 	}
975 
976 	return 0;
977 }
978 
979 int psp_dev_init(struct sp_device *sp)
980 {
981 	struct device *dev = sp->dev;
982 	struct psp_device *psp;
983 	int ret;
984 
985 	ret = -ENOMEM;
986 	psp = psp_alloc_struct(sp);
987 	if (!psp)
988 		goto e_err;
989 
990 	sp->psp_data = psp;
991 
992 	psp->vdata = (struct psp_vdata *)sp->dev_vdata->psp_vdata;
993 	if (!psp->vdata) {
994 		ret = -ENODEV;
995 		dev_err(dev, "missing driver data\n");
996 		goto e_err;
997 	}
998 
999 	psp->io_regs = sp->io_map;
1000 
1001 	ret = psp_check_sev_support(psp);
1002 	if (ret)
1003 		goto e_disable;
1004 
1005 	/* Disable and clear interrupts until ready */
1006 	iowrite32(0, psp->io_regs + psp->vdata->inten_reg);
1007 	iowrite32(-1, psp->io_regs + psp->vdata->intsts_reg);
1008 
1009 	/* Request an irq */
1010 	ret = sp_request_psp_irq(psp->sp, psp_irq_handler, psp->name, psp);
1011 	if (ret) {
1012 		dev_err(dev, "psp: unable to allocate an IRQ\n");
1013 		goto e_err;
1014 	}
1015 
1016 	ret = sev_misc_init(psp);
1017 	if (ret)
1018 		goto e_irq;
1019 
1020 	if (sp->set_psp_master_device)
1021 		sp->set_psp_master_device(sp);
1022 
1023 	/* Enable interrupt */
1024 	iowrite32(-1, psp->io_regs + psp->vdata->inten_reg);
1025 
1026 	dev_notice(dev, "psp enabled\n");
1027 
1028 	return 0;
1029 
1030 e_irq:
1031 	sp_free_psp_irq(psp->sp, psp);
1032 e_err:
1033 	sp->psp_data = NULL;
1034 
1035 	dev_notice(dev, "psp initialization failed\n");
1036 
1037 	return ret;
1038 
1039 e_disable:
1040 	sp->psp_data = NULL;
1041 
1042 	return ret;
1043 }
1044 
1045 void psp_dev_destroy(struct sp_device *sp)
1046 {
1047 	struct psp_device *psp = sp->psp_data;
1048 
1049 	if (!psp)
1050 		return;
1051 
1052 	if (psp->sev_misc)
1053 		kref_put(&misc_dev->refcount, sev_exit);
1054 
1055 	sp_free_psp_irq(sp, psp);
1056 }
1057 
1058 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1059 				void *data, int *error)
1060 {
1061 	if (!filep || filep->f_op != &sev_fops)
1062 		return -EBADF;
1063 
1064 	return  sev_do_cmd(cmd, data, error);
1065 }
1066 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1067 
1068 void psp_pci_init(void)
1069 {
1070 	struct sp_device *sp;
1071 	int error, rc;
1072 
1073 	sp = sp_get_psp_master_device();
1074 	if (!sp)
1075 		return;
1076 
1077 	psp_master = sp->psp_data;
1078 
1079 	psp_timeout = psp_probe_timeout;
1080 
1081 	if (sev_get_api_version())
1082 		goto err;
1083 
1084 	/*
1085 	 * If platform is not in UNINIT state then firmware upgrade and/or
1086 	 * platform INIT command will fail. These command require UNINIT state.
1087 	 *
1088 	 * In a normal boot we should never run into case where the firmware
1089 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1090 	 * may not go through a typical shutdown sequence and may leave the
1091 	 * firmware in INIT or WORKING state.
1092 	 */
1093 
1094 	if (psp_master->sev_state != SEV_STATE_UNINIT) {
1095 		sev_platform_shutdown(NULL);
1096 		psp_master->sev_state = SEV_STATE_UNINIT;
1097 	}
1098 
1099 	if (sev_version_greater_or_equal(0, 15) &&
1100 	    sev_update_firmware(psp_master->dev) == 0)
1101 		sev_get_api_version();
1102 
1103 	/* Initialize the platform */
1104 	rc = sev_platform_init(&error);
1105 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1106 		/*
1107 		 * INIT command returned an integrity check failure
1108 		 * status code, meaning that firmware load and
1109 		 * validation of SEV related persistent data has
1110 		 * failed and persistent state has been erased.
1111 		 * Retrying INIT command here should succeed.
1112 		 */
1113 		dev_dbg(sp->dev, "SEV: retrying INIT command");
1114 		rc = sev_platform_init(&error);
1115 	}
1116 
1117 	if (rc) {
1118 		dev_err(sp->dev, "SEV: failed to INIT error %#x\n", error);
1119 		return;
1120 	}
1121 
1122 	dev_info(sp->dev, "SEV API:%d.%d build:%d\n", psp_master->api_major,
1123 		 psp_master->api_minor, psp_master->build);
1124 
1125 	return;
1126 
1127 err:
1128 	psp_master = NULL;
1129 }
1130 
1131 void psp_pci_exit(void)
1132 {
1133 	if (!psp_master)
1134 		return;
1135 
1136 	sev_platform_shutdown(NULL);
1137 }
1138