1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Arm Firmware Framework for ARMv8-A(FFA) interface driver
4  *
5  * The Arm FFA specification[1] describes a software architecture to
6  * leverages the virtualization extension to isolate software images
7  * provided by an ecosystem of vendors from each other and describes
8  * interfaces that standardize communication between the various software
9  * images including communication between images in the Secure world and
10  * Normal world. Any Hypervisor could use the FFA interfaces to enable
11  * communication between VMs it manages.
12  *
13  * The Hypervisor a.k.a Partition managers in FFA terminology can assign
14  * system resources(Memory regions, Devices, CPU cycles) to the partitions
15  * and manage isolation amongst them.
16  *
17  * [1] https://developer.arm.com/docs/den0077/latest
18  *
19  * Copyright (C) 2021 ARM Ltd.
20  */
21 
22 #define DRIVER_NAME "ARM FF-A"
23 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
24 
25 #include <linux/arm_ffa.h>
26 #include <linux/bitfield.h>
27 #include <linux/device.h>
28 #include <linux/io.h>
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/mm.h>
32 #include <linux/scatterlist.h>
33 #include <linux/slab.h>
34 #include <linux/uuid.h>
35 
36 #include "common.h"
37 
38 #define FFA_DRIVER_VERSION	FFA_VERSION_1_0
39 
40 #define FFA_SMC(calling_convention, func_num)				\
41 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, (calling_convention),	\
42 			   ARM_SMCCC_OWNER_STANDARD, (func_num))
43 
44 #define FFA_SMC_32(func_num)	FFA_SMC(ARM_SMCCC_SMC_32, (func_num))
45 #define FFA_SMC_64(func_num)	FFA_SMC(ARM_SMCCC_SMC_64, (func_num))
46 
47 #define FFA_ERROR			FFA_SMC_32(0x60)
48 #define FFA_SUCCESS			FFA_SMC_32(0x61)
49 #define FFA_INTERRUPT			FFA_SMC_32(0x62)
50 #define FFA_VERSION			FFA_SMC_32(0x63)
51 #define FFA_FEATURES			FFA_SMC_32(0x64)
52 #define FFA_RX_RELEASE			FFA_SMC_32(0x65)
53 #define FFA_RXTX_MAP			FFA_SMC_32(0x66)
54 #define FFA_FN64_RXTX_MAP		FFA_SMC_64(0x66)
55 #define FFA_RXTX_UNMAP			FFA_SMC_32(0x67)
56 #define FFA_PARTITION_INFO_GET		FFA_SMC_32(0x68)
57 #define FFA_ID_GET			FFA_SMC_32(0x69)
58 #define FFA_MSG_POLL			FFA_SMC_32(0x6A)
59 #define FFA_MSG_WAIT			FFA_SMC_32(0x6B)
60 #define FFA_YIELD			FFA_SMC_32(0x6C)
61 #define FFA_RUN				FFA_SMC_32(0x6D)
62 #define FFA_MSG_SEND			FFA_SMC_32(0x6E)
63 #define FFA_MSG_SEND_DIRECT_REQ		FFA_SMC_32(0x6F)
64 #define FFA_FN64_MSG_SEND_DIRECT_REQ	FFA_SMC_64(0x6F)
65 #define FFA_MSG_SEND_DIRECT_RESP	FFA_SMC_32(0x70)
66 #define FFA_FN64_MSG_SEND_DIRECT_RESP	FFA_SMC_64(0x70)
67 #define FFA_MEM_DONATE			FFA_SMC_32(0x71)
68 #define FFA_FN64_MEM_DONATE		FFA_SMC_64(0x71)
69 #define FFA_MEM_LEND			FFA_SMC_32(0x72)
70 #define FFA_FN64_MEM_LEND		FFA_SMC_64(0x72)
71 #define FFA_MEM_SHARE			FFA_SMC_32(0x73)
72 #define FFA_FN64_MEM_SHARE		FFA_SMC_64(0x73)
73 #define FFA_MEM_RETRIEVE_REQ		FFA_SMC_32(0x74)
74 #define FFA_FN64_MEM_RETRIEVE_REQ	FFA_SMC_64(0x74)
75 #define FFA_MEM_RETRIEVE_RESP		FFA_SMC_32(0x75)
76 #define FFA_MEM_RELINQUISH		FFA_SMC_32(0x76)
77 #define FFA_MEM_RECLAIM			FFA_SMC_32(0x77)
78 #define FFA_MEM_OP_PAUSE		FFA_SMC_32(0x78)
79 #define FFA_MEM_OP_RESUME		FFA_SMC_32(0x79)
80 #define FFA_MEM_FRAG_RX			FFA_SMC_32(0x7A)
81 #define FFA_MEM_FRAG_TX			FFA_SMC_32(0x7B)
82 #define FFA_NORMAL_WORLD_RESUME		FFA_SMC_32(0x7C)
83 
84 /*
85  * For some calls it is necessary to use SMC64 to pass or return 64-bit values.
86  * For such calls FFA_FN_NATIVE(name) will choose the appropriate
87  * (native-width) function ID.
88  */
89 #ifdef CONFIG_64BIT
90 #define FFA_FN_NATIVE(name)	FFA_FN64_##name
91 #else
92 #define FFA_FN_NATIVE(name)	FFA_##name
93 #endif
94 
95 /* FFA error codes. */
96 #define FFA_RET_SUCCESS            (0)
97 #define FFA_RET_NOT_SUPPORTED      (-1)
98 #define FFA_RET_INVALID_PARAMETERS (-2)
99 #define FFA_RET_NO_MEMORY          (-3)
100 #define FFA_RET_BUSY               (-4)
101 #define FFA_RET_INTERRUPTED        (-5)
102 #define FFA_RET_DENIED             (-6)
103 #define FFA_RET_RETRY              (-7)
104 #define FFA_RET_ABORTED            (-8)
105 
106 #define MAJOR_VERSION_MASK	GENMASK(30, 16)
107 #define MINOR_VERSION_MASK	GENMASK(15, 0)
108 #define MAJOR_VERSION(x)	((u16)(FIELD_GET(MAJOR_VERSION_MASK, (x))))
109 #define MINOR_VERSION(x)	((u16)(FIELD_GET(MINOR_VERSION_MASK, (x))))
110 #define PACK_VERSION_INFO(major, minor)			\
111 	(FIELD_PREP(MAJOR_VERSION_MASK, (major)) |	\
112 	 FIELD_PREP(MINOR_VERSION_MASK, (minor)))
113 #define FFA_VERSION_1_0		PACK_VERSION_INFO(1, 0)
114 #define FFA_MIN_VERSION		FFA_VERSION_1_0
115 
116 #define SENDER_ID_MASK		GENMASK(31, 16)
117 #define RECEIVER_ID_MASK	GENMASK(15, 0)
118 #define SENDER_ID(x)		((u16)(FIELD_GET(SENDER_ID_MASK, (x))))
119 #define RECEIVER_ID(x)		((u16)(FIELD_GET(RECEIVER_ID_MASK, (x))))
120 #define PACK_TARGET_INFO(s, r)		\
121 	(FIELD_PREP(SENDER_ID_MASK, (s)) | FIELD_PREP(RECEIVER_ID_MASK, (r)))
122 
123 /**
124  * FF-A specification mentions explicitly about '4K pages'. This should
125  * not be confused with the kernel PAGE_SIZE, which is the translation
126  * granule kernel is configured and may be one among 4K, 16K and 64K.
127  */
128 #define FFA_PAGE_SIZE		SZ_4K
129 /*
130  * Keeping RX TX buffer size as 4K for now
131  * 64K may be preferred to keep it min a page in 64K PAGE_SIZE config
132  */
133 #define RXTX_BUFFER_SIZE	SZ_4K
134 
135 static ffa_fn *invoke_ffa_fn;
136 
137 static const int ffa_linux_errmap[] = {
138 	/* better than switch case as long as return value is continuous */
139 	0,		/* FFA_RET_SUCCESS */
140 	-EOPNOTSUPP,	/* FFA_RET_NOT_SUPPORTED */
141 	-EINVAL,	/* FFA_RET_INVALID_PARAMETERS */
142 	-ENOMEM,	/* FFA_RET_NO_MEMORY */
143 	-EBUSY,		/* FFA_RET_BUSY */
144 	-EINTR,		/* FFA_RET_INTERRUPTED */
145 	-EACCES,	/* FFA_RET_DENIED */
146 	-EAGAIN,	/* FFA_RET_RETRY */
147 	-ECANCELED,	/* FFA_RET_ABORTED */
148 };
149 
150 static inline int ffa_to_linux_errno(int errno)
151 {
152 	if (errno < FFA_RET_SUCCESS && errno >= -ARRAY_SIZE(ffa_linux_errmap))
153 		return ffa_linux_errmap[-errno];
154 	return -EINVAL;
155 }
156 
157 struct ffa_drv_info {
158 	u32 version;
159 	u16 vm_id;
160 	struct mutex rx_lock; /* lock to protect Rx buffer */
161 	struct mutex tx_lock; /* lock to protect Tx buffer */
162 	void *rx_buffer;
163 	void *tx_buffer;
164 };
165 
166 static struct ffa_drv_info *drv_info;
167 
168 static int ffa_version_check(u32 *version)
169 {
170 	ffa_value_t ver;
171 
172 	invoke_ffa_fn((ffa_value_t){
173 		      .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION,
174 		      }, &ver);
175 
176 	if (ver.a0 == FFA_RET_NOT_SUPPORTED) {
177 		pr_info("FFA_VERSION returned not supported\n");
178 		return -EOPNOTSUPP;
179 	}
180 
181 	if (ver.a0 < FFA_MIN_VERSION || ver.a0 > FFA_DRIVER_VERSION) {
182 		pr_err("Incompatible version %d.%d found\n",
183 		       MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0));
184 		return -EINVAL;
185 	}
186 
187 	*version = ver.a0;
188 	pr_info("Version %d.%d found\n", MAJOR_VERSION(ver.a0),
189 		MINOR_VERSION(ver.a0));
190 	return 0;
191 }
192 
193 static int ffa_rx_release(void)
194 {
195 	ffa_value_t ret;
196 
197 	invoke_ffa_fn((ffa_value_t){
198 		      .a0 = FFA_RX_RELEASE,
199 		      }, &ret);
200 
201 	if (ret.a0 == FFA_ERROR)
202 		return ffa_to_linux_errno((int)ret.a2);
203 
204 	/* check for ret.a0 == FFA_RX_RELEASE ? */
205 
206 	return 0;
207 }
208 
209 static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
210 {
211 	ffa_value_t ret;
212 
213 	invoke_ffa_fn((ffa_value_t){
214 		      .a0 = FFA_FN_NATIVE(RXTX_MAP),
215 		      .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt,
216 		      }, &ret);
217 
218 	if (ret.a0 == FFA_ERROR)
219 		return ffa_to_linux_errno((int)ret.a2);
220 
221 	return 0;
222 }
223 
224 static int ffa_rxtx_unmap(u16 vm_id)
225 {
226 	ffa_value_t ret;
227 
228 	invoke_ffa_fn((ffa_value_t){
229 		      .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0),
230 		      }, &ret);
231 
232 	if (ret.a0 == FFA_ERROR)
233 		return ffa_to_linux_errno((int)ret.a2);
234 
235 	return 0;
236 }
237 
238 /* buffer must be sizeof(struct ffa_partition_info) * num_partitions */
239 static int
240 __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3,
241 			 struct ffa_partition_info *buffer, int num_partitions)
242 {
243 	int count;
244 	ffa_value_t partition_info;
245 
246 	mutex_lock(&drv_info->rx_lock);
247 	invoke_ffa_fn((ffa_value_t){
248 		      .a0 = FFA_PARTITION_INFO_GET,
249 		      .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3,
250 		      }, &partition_info);
251 
252 	if (partition_info.a0 == FFA_ERROR) {
253 		mutex_unlock(&drv_info->rx_lock);
254 		return ffa_to_linux_errno((int)partition_info.a2);
255 	}
256 
257 	count = partition_info.a2;
258 
259 	if (buffer && count <= num_partitions)
260 		memcpy(buffer, drv_info->rx_buffer, sizeof(*buffer) * count);
261 
262 	ffa_rx_release();
263 
264 	mutex_unlock(&drv_info->rx_lock);
265 
266 	return count;
267 }
268 
269 /* buffer is allocated and caller must free the same if returned count > 0 */
270 static int
271 ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer)
272 {
273 	int count;
274 	u32 uuid0_4[4];
275 	struct ffa_partition_info *pbuf;
276 
277 	export_uuid((u8 *)uuid0_4, uuid);
278 	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
279 					 uuid0_4[3], NULL, 0);
280 	if (count <= 0)
281 		return count;
282 
283 	pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL);
284 	if (!pbuf)
285 		return -ENOMEM;
286 
287 	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
288 					 uuid0_4[3], pbuf, count);
289 	if (count <= 0)
290 		kfree(pbuf);
291 	else
292 		*buffer = pbuf;
293 
294 	return count;
295 }
296 
297 #define VM_ID_MASK	GENMASK(15, 0)
298 static int ffa_id_get(u16 *vm_id)
299 {
300 	ffa_value_t id;
301 
302 	invoke_ffa_fn((ffa_value_t){
303 		      .a0 = FFA_ID_GET,
304 		      }, &id);
305 
306 	if (id.a0 == FFA_ERROR)
307 		return ffa_to_linux_errno((int)id.a2);
308 
309 	*vm_id = FIELD_GET(VM_ID_MASK, (id.a2));
310 
311 	return 0;
312 }
313 
314 static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit,
315 				   struct ffa_send_direct_data *data)
316 {
317 	u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
318 	ffa_value_t ret;
319 
320 	if (mode_32bit) {
321 		req_id = FFA_MSG_SEND_DIRECT_REQ;
322 		resp_id = FFA_MSG_SEND_DIRECT_RESP;
323 	} else {
324 		req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ);
325 		resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP);
326 	}
327 
328 	invoke_ffa_fn((ffa_value_t){
329 		      .a0 = req_id, .a1 = src_dst_ids, .a2 = 0,
330 		      .a3 = data->data0, .a4 = data->data1, .a5 = data->data2,
331 		      .a6 = data->data3, .a7 = data->data4,
332 		      }, &ret);
333 
334 	while (ret.a0 == FFA_INTERRUPT)
335 		invoke_ffa_fn((ffa_value_t){
336 			      .a0 = FFA_RUN, .a1 = ret.a1,
337 			      }, &ret);
338 
339 	if (ret.a0 == FFA_ERROR)
340 		return ffa_to_linux_errno((int)ret.a2);
341 
342 	if (ret.a0 == resp_id) {
343 		data->data0 = ret.a3;
344 		data->data1 = ret.a4;
345 		data->data2 = ret.a5;
346 		data->data3 = ret.a6;
347 		data->data4 = ret.a7;
348 		return 0;
349 	}
350 
351 	return -EINVAL;
352 }
353 
354 static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
355 			      u32 frag_len, u32 len, u64 *handle)
356 {
357 	ffa_value_t ret;
358 
359 	invoke_ffa_fn((ffa_value_t){
360 		      .a0 = func_id, .a1 = len, .a2 = frag_len,
361 		      .a3 = buf, .a4 = buf_sz,
362 		      }, &ret);
363 
364 	while (ret.a0 == FFA_MEM_OP_PAUSE)
365 		invoke_ffa_fn((ffa_value_t){
366 			      .a0 = FFA_MEM_OP_RESUME,
367 			      .a1 = ret.a1, .a2 = ret.a2,
368 			      }, &ret);
369 
370 	if (ret.a0 == FFA_ERROR)
371 		return ffa_to_linux_errno((int)ret.a2);
372 
373 	if (ret.a0 != FFA_SUCCESS)
374 		return -EOPNOTSUPP;
375 
376 	if (handle)
377 		*handle = PACK_HANDLE(ret.a2, ret.a3);
378 
379 	return frag_len;
380 }
381 
382 static int ffa_mem_next_frag(u64 handle, u32 frag_len)
383 {
384 	ffa_value_t ret;
385 
386 	invoke_ffa_fn((ffa_value_t){
387 		      .a0 = FFA_MEM_FRAG_TX,
388 		      .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle),
389 		      .a3 = frag_len,
390 		      }, &ret);
391 
392 	while (ret.a0 == FFA_MEM_OP_PAUSE)
393 		invoke_ffa_fn((ffa_value_t){
394 			      .a0 = FFA_MEM_OP_RESUME,
395 			      .a1 = ret.a1, .a2 = ret.a2,
396 			      }, &ret);
397 
398 	if (ret.a0 == FFA_ERROR)
399 		return ffa_to_linux_errno((int)ret.a2);
400 
401 	if (ret.a0 != FFA_MEM_FRAG_RX)
402 		return -EOPNOTSUPP;
403 
404 	return ret.a3;
405 }
406 
407 static int
408 ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
409 		      u32 len, u64 *handle, bool first)
410 {
411 	if (!first)
412 		return ffa_mem_next_frag(*handle, frag_len);
413 
414 	return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle);
415 }
416 
417 static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
418 {
419 	u32 num_pages = 0;
420 
421 	do {
422 		num_pages += sg->length / FFA_PAGE_SIZE;
423 	} while ((sg = sg_next(sg)));
424 
425 	return num_pages;
426 }
427 
428 static int
429 ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
430 		       struct ffa_mem_ops_args *args)
431 {
432 	int rc = 0;
433 	bool first = true;
434 	phys_addr_t addr = 0;
435 	struct ffa_composite_mem_region *composite;
436 	struct ffa_mem_region_addr_range *constituents;
437 	struct ffa_mem_region_attributes *ep_mem_access;
438 	struct ffa_mem_region *mem_region = buffer;
439 	u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg);
440 
441 	mem_region->tag = args->tag;
442 	mem_region->flags = args->flags;
443 	mem_region->sender_id = drv_info->vm_id;
444 	mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
445 				 FFA_MEM_INNER_SHAREABLE;
446 	ep_mem_access = &mem_region->ep_mem_access[0];
447 
448 	for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
449 		ep_mem_access->receiver = args->attrs[idx].receiver;
450 		ep_mem_access->attrs = args->attrs[idx].attrs;
451 		ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
452 	}
453 	mem_region->ep_count = args->nattrs;
454 
455 	composite = buffer + COMPOSITE_OFFSET(args->nattrs);
456 	composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
457 	composite->addr_range_cnt = num_entries;
458 
459 	length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
460 	frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
461 	if (frag_len > max_fragsize)
462 		return -ENXIO;
463 
464 	if (!args->use_txbuf) {
465 		addr = virt_to_phys(buffer);
466 		buf_sz = max_fragsize / FFA_PAGE_SIZE;
467 	}
468 
469 	constituents = buffer + frag_len;
470 	idx = 0;
471 	do {
472 		if (frag_len == max_fragsize) {
473 			rc = ffa_transmit_fragment(func_id, addr, buf_sz,
474 						   frag_len, length,
475 						   &args->g_handle, first);
476 			if (rc < 0)
477 				return -ENXIO;
478 
479 			first = false;
480 			idx = 0;
481 			frag_len = 0;
482 			constituents = buffer;
483 		}
484 
485 		if ((void *)constituents - buffer > max_fragsize) {
486 			pr_err("Memory Region Fragment > Tx Buffer size\n");
487 			return -EFAULT;
488 		}
489 
490 		constituents->address = sg_phys(args->sg);
491 		constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
492 		constituents++;
493 		frag_len += sizeof(struct ffa_mem_region_addr_range);
494 	} while ((args->sg = sg_next(args->sg)));
495 
496 	return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
497 				     length, &args->g_handle, first);
498 }
499 
500 static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
501 {
502 	int ret;
503 	void *buffer;
504 
505 	if (!args->use_txbuf) {
506 		buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
507 		if (!buffer)
508 			return -ENOMEM;
509 	} else {
510 		buffer = drv_info->tx_buffer;
511 		mutex_lock(&drv_info->tx_lock);
512 	}
513 
514 	ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
515 
516 	if (args->use_txbuf)
517 		mutex_unlock(&drv_info->tx_lock);
518 	else
519 		free_pages_exact(buffer, RXTX_BUFFER_SIZE);
520 
521 	return ret < 0 ? ret : 0;
522 }
523 
524 static int ffa_memory_reclaim(u64 g_handle, u32 flags)
525 {
526 	ffa_value_t ret;
527 
528 	invoke_ffa_fn((ffa_value_t){
529 		      .a0 = FFA_MEM_RECLAIM,
530 		      .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle),
531 		      .a3 = flags,
532 		      }, &ret);
533 
534 	if (ret.a0 == FFA_ERROR)
535 		return ffa_to_linux_errno((int)ret.a2);
536 
537 	return 0;
538 }
539 
540 static u32 ffa_api_version_get(void)
541 {
542 	return drv_info->version;
543 }
544 
545 static int ffa_partition_info_get(const char *uuid_str,
546 				  struct ffa_partition_info *buffer)
547 {
548 	int count;
549 	uuid_t uuid;
550 	struct ffa_partition_info *pbuf;
551 
552 	if (uuid_parse(uuid_str, &uuid)) {
553 		pr_err("invalid uuid (%s)\n", uuid_str);
554 		return -ENODEV;
555 	}
556 
557 	count = ffa_partition_probe(&uuid_null, &pbuf);
558 	if (count <= 0)
559 		return -ENOENT;
560 
561 	memcpy(buffer, pbuf, sizeof(*pbuf) * count);
562 	kfree(pbuf);
563 	return 0;
564 }
565 
566 static void ffa_mode_32bit_set(struct ffa_device *dev)
567 {
568 	dev->mode_32bit = true;
569 }
570 
571 static int ffa_sync_send_receive(struct ffa_device *dev,
572 				 struct ffa_send_direct_data *data)
573 {
574 	return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id,
575 				       dev->mode_32bit, data);
576 }
577 
578 static int
579 ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args)
580 {
581 	if (dev->mode_32bit)
582 		return ffa_memory_ops(FFA_MEM_SHARE, args);
583 
584 	return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
585 }
586 
587 static const struct ffa_dev_ops ffa_ops = {
588 	.api_version_get = ffa_api_version_get,
589 	.partition_info_get = ffa_partition_info_get,
590 	.mode_32bit_set = ffa_mode_32bit_set,
591 	.sync_send_receive = ffa_sync_send_receive,
592 	.memory_reclaim = ffa_memory_reclaim,
593 	.memory_share = ffa_memory_share,
594 };
595 
596 const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
597 {
598 	if (ffa_device_is_valid(dev))
599 		return &ffa_ops;
600 
601 	return NULL;
602 }
603 EXPORT_SYMBOL_GPL(ffa_dev_ops_get);
604 
605 void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid)
606 {
607 	int count, idx;
608 	struct ffa_partition_info *pbuf, *tpbuf;
609 
610 	count = ffa_partition_probe(uuid, &pbuf);
611 	if (count <= 0)
612 		return;
613 
614 	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++)
615 		if (tpbuf->id == ffa_dev->vm_id)
616 			uuid_copy(&ffa_dev->uuid, uuid);
617 	kfree(pbuf);
618 }
619 
620 static void ffa_setup_partitions(void)
621 {
622 	int count, idx;
623 	struct ffa_device *ffa_dev;
624 	struct ffa_partition_info *pbuf, *tpbuf;
625 
626 	count = ffa_partition_probe(&uuid_null, &pbuf);
627 	if (count <= 0) {
628 		pr_info("%s: No partitions found, error %d\n", __func__, count);
629 		return;
630 	}
631 
632 	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) {
633 		/* Note that the &uuid_null parameter will require
634 		 * ffa_device_match() to find the UUID of this partition id
635 		 * with help of ffa_device_match_uuid(). Once the FF-A spec
636 		 * is updated to provide correct UUID here for each partition
637 		 * as part of the discovery API, we need to pass the
638 		 * discovered UUID here instead.
639 		 */
640 		ffa_dev = ffa_device_register(&uuid_null, tpbuf->id);
641 		if (!ffa_dev) {
642 			pr_err("%s: failed to register partition ID 0x%x\n",
643 			       __func__, tpbuf->id);
644 			continue;
645 		}
646 
647 		ffa_dev_set_drvdata(ffa_dev, drv_info);
648 	}
649 	kfree(pbuf);
650 }
651 
652 static int __init ffa_init(void)
653 {
654 	int ret;
655 
656 	ret = ffa_transport_init(&invoke_ffa_fn);
657 	if (ret)
658 		return ret;
659 
660 	ret = arm_ffa_bus_init();
661 	if (ret)
662 		return ret;
663 
664 	drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
665 	if (!drv_info) {
666 		ret = -ENOMEM;
667 		goto ffa_bus_exit;
668 	}
669 
670 	ret = ffa_version_check(&drv_info->version);
671 	if (ret)
672 		goto free_drv_info;
673 
674 	if (ffa_id_get(&drv_info->vm_id)) {
675 		pr_err("failed to obtain VM id for self\n");
676 		ret = -ENODEV;
677 		goto free_drv_info;
678 	}
679 
680 	drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
681 	if (!drv_info->rx_buffer) {
682 		ret = -ENOMEM;
683 		goto free_pages;
684 	}
685 
686 	drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
687 	if (!drv_info->tx_buffer) {
688 		ret = -ENOMEM;
689 		goto free_pages;
690 	}
691 
692 	ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer),
693 			   virt_to_phys(drv_info->rx_buffer),
694 			   RXTX_BUFFER_SIZE / FFA_PAGE_SIZE);
695 	if (ret) {
696 		pr_err("failed to register FFA RxTx buffers\n");
697 		goto free_pages;
698 	}
699 
700 	mutex_init(&drv_info->rx_lock);
701 	mutex_init(&drv_info->tx_lock);
702 
703 	ffa_setup_partitions();
704 
705 	return 0;
706 free_pages:
707 	if (drv_info->tx_buffer)
708 		free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
709 	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
710 free_drv_info:
711 	kfree(drv_info);
712 ffa_bus_exit:
713 	arm_ffa_bus_exit();
714 	return ret;
715 }
716 subsys_initcall(ffa_init);
717 
718 static void __exit ffa_exit(void)
719 {
720 	ffa_rxtx_unmap(drv_info->vm_id);
721 	free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
722 	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
723 	kfree(drv_info);
724 	arm_ffa_bus_exit();
725 }
726 module_exit(ffa_exit);
727 
728 MODULE_ALIAS("arm-ffa");
729 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
730 MODULE_DESCRIPTION("Arm FF-A interface driver");
731 MODULE_LICENSE("GPL v2");
732