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 	int err_idx = -errno;
153 
154 	if (err_idx >= 0 && err_idx < ARRAY_SIZE(ffa_linux_errmap))
155 		return ffa_linux_errmap[err_idx];
156 	return -EINVAL;
157 }
158 
159 struct ffa_drv_info {
160 	u32 version;
161 	u16 vm_id;
162 	struct mutex rx_lock; /* lock to protect Rx buffer */
163 	struct mutex tx_lock; /* lock to protect Tx buffer */
164 	void *rx_buffer;
165 	void *tx_buffer;
166 };
167 
168 static struct ffa_drv_info *drv_info;
169 
170 static int ffa_version_check(u32 *version)
171 {
172 	ffa_value_t ver;
173 
174 	invoke_ffa_fn((ffa_value_t){
175 		      .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION,
176 		      }, &ver);
177 
178 	if (ver.a0 == FFA_RET_NOT_SUPPORTED) {
179 		pr_info("FFA_VERSION returned not supported\n");
180 		return -EOPNOTSUPP;
181 	}
182 
183 	if (ver.a0 < FFA_MIN_VERSION || ver.a0 > FFA_DRIVER_VERSION) {
184 		pr_err("Incompatible version %d.%d found\n",
185 		       MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0));
186 		return -EINVAL;
187 	}
188 
189 	*version = ver.a0;
190 	pr_info("Version %d.%d found\n", MAJOR_VERSION(ver.a0),
191 		MINOR_VERSION(ver.a0));
192 	return 0;
193 }
194 
195 static int ffa_rx_release(void)
196 {
197 	ffa_value_t ret;
198 
199 	invoke_ffa_fn((ffa_value_t){
200 		      .a0 = FFA_RX_RELEASE,
201 		      }, &ret);
202 
203 	if (ret.a0 == FFA_ERROR)
204 		return ffa_to_linux_errno((int)ret.a2);
205 
206 	/* check for ret.a0 == FFA_RX_RELEASE ? */
207 
208 	return 0;
209 }
210 
211 static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
212 {
213 	ffa_value_t ret;
214 
215 	invoke_ffa_fn((ffa_value_t){
216 		      .a0 = FFA_FN_NATIVE(RXTX_MAP),
217 		      .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt,
218 		      }, &ret);
219 
220 	if (ret.a0 == FFA_ERROR)
221 		return ffa_to_linux_errno((int)ret.a2);
222 
223 	return 0;
224 }
225 
226 static int ffa_rxtx_unmap(u16 vm_id)
227 {
228 	ffa_value_t ret;
229 
230 	invoke_ffa_fn((ffa_value_t){
231 		      .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0),
232 		      }, &ret);
233 
234 	if (ret.a0 == FFA_ERROR)
235 		return ffa_to_linux_errno((int)ret.a2);
236 
237 	return 0;
238 }
239 
240 /* buffer must be sizeof(struct ffa_partition_info) * num_partitions */
241 static int
242 __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3,
243 			 struct ffa_partition_info *buffer, int num_partitions)
244 {
245 	int count;
246 	ffa_value_t partition_info;
247 
248 	mutex_lock(&drv_info->rx_lock);
249 	invoke_ffa_fn((ffa_value_t){
250 		      .a0 = FFA_PARTITION_INFO_GET,
251 		      .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3,
252 		      }, &partition_info);
253 
254 	if (partition_info.a0 == FFA_ERROR) {
255 		mutex_unlock(&drv_info->rx_lock);
256 		return ffa_to_linux_errno((int)partition_info.a2);
257 	}
258 
259 	count = partition_info.a2;
260 
261 	if (buffer && count <= num_partitions)
262 		memcpy(buffer, drv_info->rx_buffer, sizeof(*buffer) * count);
263 
264 	ffa_rx_release();
265 
266 	mutex_unlock(&drv_info->rx_lock);
267 
268 	return count;
269 }
270 
271 /* buffer is allocated and caller must free the same if returned count > 0 */
272 static int
273 ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer)
274 {
275 	int count;
276 	u32 uuid0_4[4];
277 	struct ffa_partition_info *pbuf;
278 
279 	export_uuid((u8 *)uuid0_4, uuid);
280 	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
281 					 uuid0_4[3], NULL, 0);
282 	if (count <= 0)
283 		return count;
284 
285 	pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL);
286 	if (!pbuf)
287 		return -ENOMEM;
288 
289 	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
290 					 uuid0_4[3], pbuf, count);
291 	if (count <= 0)
292 		kfree(pbuf);
293 	else
294 		*buffer = pbuf;
295 
296 	return count;
297 }
298 
299 #define VM_ID_MASK	GENMASK(15, 0)
300 static int ffa_id_get(u16 *vm_id)
301 {
302 	ffa_value_t id;
303 
304 	invoke_ffa_fn((ffa_value_t){
305 		      .a0 = FFA_ID_GET,
306 		      }, &id);
307 
308 	if (id.a0 == FFA_ERROR)
309 		return ffa_to_linux_errno((int)id.a2);
310 
311 	*vm_id = FIELD_GET(VM_ID_MASK, (id.a2));
312 
313 	return 0;
314 }
315 
316 static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit,
317 				   struct ffa_send_direct_data *data)
318 {
319 	u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
320 	ffa_value_t ret;
321 
322 	if (mode_32bit) {
323 		req_id = FFA_MSG_SEND_DIRECT_REQ;
324 		resp_id = FFA_MSG_SEND_DIRECT_RESP;
325 	} else {
326 		req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ);
327 		resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP);
328 	}
329 
330 	invoke_ffa_fn((ffa_value_t){
331 		      .a0 = req_id, .a1 = src_dst_ids, .a2 = 0,
332 		      .a3 = data->data0, .a4 = data->data1, .a5 = data->data2,
333 		      .a6 = data->data3, .a7 = data->data4,
334 		      }, &ret);
335 
336 	while (ret.a0 == FFA_INTERRUPT)
337 		invoke_ffa_fn((ffa_value_t){
338 			      .a0 = FFA_RUN, .a1 = ret.a1,
339 			      }, &ret);
340 
341 	if (ret.a0 == FFA_ERROR)
342 		return ffa_to_linux_errno((int)ret.a2);
343 
344 	if (ret.a0 == resp_id) {
345 		data->data0 = ret.a3;
346 		data->data1 = ret.a4;
347 		data->data2 = ret.a5;
348 		data->data3 = ret.a6;
349 		data->data4 = ret.a7;
350 		return 0;
351 	}
352 
353 	return -EINVAL;
354 }
355 
356 static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
357 			      u32 frag_len, u32 len, u64 *handle)
358 {
359 	ffa_value_t ret;
360 
361 	invoke_ffa_fn((ffa_value_t){
362 		      .a0 = func_id, .a1 = len, .a2 = frag_len,
363 		      .a3 = buf, .a4 = buf_sz,
364 		      }, &ret);
365 
366 	while (ret.a0 == FFA_MEM_OP_PAUSE)
367 		invoke_ffa_fn((ffa_value_t){
368 			      .a0 = FFA_MEM_OP_RESUME,
369 			      .a1 = ret.a1, .a2 = ret.a2,
370 			      }, &ret);
371 
372 	if (ret.a0 == FFA_ERROR)
373 		return ffa_to_linux_errno((int)ret.a2);
374 
375 	if (ret.a0 != FFA_SUCCESS)
376 		return -EOPNOTSUPP;
377 
378 	if (handle)
379 		*handle = PACK_HANDLE(ret.a2, ret.a3);
380 
381 	return frag_len;
382 }
383 
384 static int ffa_mem_next_frag(u64 handle, u32 frag_len)
385 {
386 	ffa_value_t ret;
387 
388 	invoke_ffa_fn((ffa_value_t){
389 		      .a0 = FFA_MEM_FRAG_TX,
390 		      .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle),
391 		      .a3 = frag_len,
392 		      }, &ret);
393 
394 	while (ret.a0 == FFA_MEM_OP_PAUSE)
395 		invoke_ffa_fn((ffa_value_t){
396 			      .a0 = FFA_MEM_OP_RESUME,
397 			      .a1 = ret.a1, .a2 = ret.a2,
398 			      }, &ret);
399 
400 	if (ret.a0 == FFA_ERROR)
401 		return ffa_to_linux_errno((int)ret.a2);
402 
403 	if (ret.a0 != FFA_MEM_FRAG_RX)
404 		return -EOPNOTSUPP;
405 
406 	return ret.a3;
407 }
408 
409 static int
410 ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
411 		      u32 len, u64 *handle, bool first)
412 {
413 	if (!first)
414 		return ffa_mem_next_frag(*handle, frag_len);
415 
416 	return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle);
417 }
418 
419 static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
420 {
421 	u32 num_pages = 0;
422 
423 	do {
424 		num_pages += sg->length / FFA_PAGE_SIZE;
425 	} while ((sg = sg_next(sg)));
426 
427 	return num_pages;
428 }
429 
430 static int
431 ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
432 		       struct ffa_mem_ops_args *args)
433 {
434 	int rc = 0;
435 	bool first = true;
436 	phys_addr_t addr = 0;
437 	struct ffa_composite_mem_region *composite;
438 	struct ffa_mem_region_addr_range *constituents;
439 	struct ffa_mem_region_attributes *ep_mem_access;
440 	struct ffa_mem_region *mem_region = buffer;
441 	u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg);
442 
443 	mem_region->tag = args->tag;
444 	mem_region->flags = args->flags;
445 	mem_region->sender_id = drv_info->vm_id;
446 	mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
447 				 FFA_MEM_INNER_SHAREABLE;
448 	ep_mem_access = &mem_region->ep_mem_access[0];
449 
450 	for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
451 		ep_mem_access->receiver = args->attrs[idx].receiver;
452 		ep_mem_access->attrs = args->attrs[idx].attrs;
453 		ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
454 	}
455 	mem_region->ep_count = args->nattrs;
456 
457 	composite = buffer + COMPOSITE_OFFSET(args->nattrs);
458 	composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
459 	composite->addr_range_cnt = num_entries;
460 
461 	length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
462 	frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
463 	if (frag_len > max_fragsize)
464 		return -ENXIO;
465 
466 	if (!args->use_txbuf) {
467 		addr = virt_to_phys(buffer);
468 		buf_sz = max_fragsize / FFA_PAGE_SIZE;
469 	}
470 
471 	constituents = buffer + frag_len;
472 	idx = 0;
473 	do {
474 		if (frag_len == max_fragsize) {
475 			rc = ffa_transmit_fragment(func_id, addr, buf_sz,
476 						   frag_len, length,
477 						   &args->g_handle, first);
478 			if (rc < 0)
479 				return -ENXIO;
480 
481 			first = false;
482 			idx = 0;
483 			frag_len = 0;
484 			constituents = buffer;
485 		}
486 
487 		if ((void *)constituents - buffer > max_fragsize) {
488 			pr_err("Memory Region Fragment > Tx Buffer size\n");
489 			return -EFAULT;
490 		}
491 
492 		constituents->address = sg_phys(args->sg);
493 		constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
494 		constituents++;
495 		frag_len += sizeof(struct ffa_mem_region_addr_range);
496 	} while ((args->sg = sg_next(args->sg)));
497 
498 	return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
499 				     length, &args->g_handle, first);
500 }
501 
502 static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
503 {
504 	int ret;
505 	void *buffer;
506 
507 	if (!args->use_txbuf) {
508 		buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
509 		if (!buffer)
510 			return -ENOMEM;
511 	} else {
512 		buffer = drv_info->tx_buffer;
513 		mutex_lock(&drv_info->tx_lock);
514 	}
515 
516 	ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
517 
518 	if (args->use_txbuf)
519 		mutex_unlock(&drv_info->tx_lock);
520 	else
521 		free_pages_exact(buffer, RXTX_BUFFER_SIZE);
522 
523 	return ret < 0 ? ret : 0;
524 }
525 
526 static int ffa_memory_reclaim(u64 g_handle, u32 flags)
527 {
528 	ffa_value_t ret;
529 
530 	invoke_ffa_fn((ffa_value_t){
531 		      .a0 = FFA_MEM_RECLAIM,
532 		      .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle),
533 		      .a3 = flags,
534 		      }, &ret);
535 
536 	if (ret.a0 == FFA_ERROR)
537 		return ffa_to_linux_errno((int)ret.a2);
538 
539 	return 0;
540 }
541 
542 static u32 ffa_api_version_get(void)
543 {
544 	return drv_info->version;
545 }
546 
547 static int ffa_partition_info_get(const char *uuid_str,
548 				  struct ffa_partition_info *buffer)
549 {
550 	int count;
551 	uuid_t uuid;
552 	struct ffa_partition_info *pbuf;
553 
554 	if (uuid_parse(uuid_str, &uuid)) {
555 		pr_err("invalid uuid (%s)\n", uuid_str);
556 		return -ENODEV;
557 	}
558 
559 	count = ffa_partition_probe(&uuid_null, &pbuf);
560 	if (count <= 0)
561 		return -ENOENT;
562 
563 	memcpy(buffer, pbuf, sizeof(*pbuf) * count);
564 	kfree(pbuf);
565 	return 0;
566 }
567 
568 static void ffa_mode_32bit_set(struct ffa_device *dev)
569 {
570 	dev->mode_32bit = true;
571 }
572 
573 static int ffa_sync_send_receive(struct ffa_device *dev,
574 				 struct ffa_send_direct_data *data)
575 {
576 	return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id,
577 				       dev->mode_32bit, data);
578 }
579 
580 static int
581 ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args)
582 {
583 	if (dev->mode_32bit)
584 		return ffa_memory_ops(FFA_MEM_SHARE, args);
585 
586 	return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
587 }
588 
589 static const struct ffa_dev_ops ffa_ops = {
590 	.api_version_get = ffa_api_version_get,
591 	.partition_info_get = ffa_partition_info_get,
592 	.mode_32bit_set = ffa_mode_32bit_set,
593 	.sync_send_receive = ffa_sync_send_receive,
594 	.memory_reclaim = ffa_memory_reclaim,
595 	.memory_share = ffa_memory_share,
596 };
597 
598 const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
599 {
600 	if (ffa_device_is_valid(dev))
601 		return &ffa_ops;
602 
603 	return NULL;
604 }
605 EXPORT_SYMBOL_GPL(ffa_dev_ops_get);
606 
607 void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid)
608 {
609 	int count, idx;
610 	struct ffa_partition_info *pbuf, *tpbuf;
611 
612 	count = ffa_partition_probe(uuid, &pbuf);
613 	if (count <= 0)
614 		return;
615 
616 	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++)
617 		if (tpbuf->id == ffa_dev->vm_id)
618 			uuid_copy(&ffa_dev->uuid, uuid);
619 	kfree(pbuf);
620 }
621 
622 static void ffa_setup_partitions(void)
623 {
624 	int count, idx;
625 	struct ffa_device *ffa_dev;
626 	struct ffa_partition_info *pbuf, *tpbuf;
627 
628 	count = ffa_partition_probe(&uuid_null, &pbuf);
629 	if (count <= 0) {
630 		pr_info("%s: No partitions found, error %d\n", __func__, count);
631 		return;
632 	}
633 
634 	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) {
635 		/* Note that the &uuid_null parameter will require
636 		 * ffa_device_match() to find the UUID of this partition id
637 		 * with help of ffa_device_match_uuid(). Once the FF-A spec
638 		 * is updated to provide correct UUID here for each partition
639 		 * as part of the discovery API, we need to pass the
640 		 * discovered UUID here instead.
641 		 */
642 		ffa_dev = ffa_device_register(&uuid_null, tpbuf->id);
643 		if (!ffa_dev) {
644 			pr_err("%s: failed to register partition ID 0x%x\n",
645 			       __func__, tpbuf->id);
646 			continue;
647 		}
648 
649 		ffa_dev_set_drvdata(ffa_dev, drv_info);
650 	}
651 	kfree(pbuf);
652 }
653 
654 static int __init ffa_init(void)
655 {
656 	int ret;
657 
658 	ret = ffa_transport_init(&invoke_ffa_fn);
659 	if (ret)
660 		return ret;
661 
662 	ret = arm_ffa_bus_init();
663 	if (ret)
664 		return ret;
665 
666 	drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
667 	if (!drv_info) {
668 		ret = -ENOMEM;
669 		goto ffa_bus_exit;
670 	}
671 
672 	ret = ffa_version_check(&drv_info->version);
673 	if (ret)
674 		goto free_drv_info;
675 
676 	if (ffa_id_get(&drv_info->vm_id)) {
677 		pr_err("failed to obtain VM id for self\n");
678 		ret = -ENODEV;
679 		goto free_drv_info;
680 	}
681 
682 	drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
683 	if (!drv_info->rx_buffer) {
684 		ret = -ENOMEM;
685 		goto free_pages;
686 	}
687 
688 	drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
689 	if (!drv_info->tx_buffer) {
690 		ret = -ENOMEM;
691 		goto free_pages;
692 	}
693 
694 	ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer),
695 			   virt_to_phys(drv_info->rx_buffer),
696 			   RXTX_BUFFER_SIZE / FFA_PAGE_SIZE);
697 	if (ret) {
698 		pr_err("failed to register FFA RxTx buffers\n");
699 		goto free_pages;
700 	}
701 
702 	mutex_init(&drv_info->rx_lock);
703 	mutex_init(&drv_info->tx_lock);
704 
705 	ffa_setup_partitions();
706 
707 	return 0;
708 free_pages:
709 	if (drv_info->tx_buffer)
710 		free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
711 	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
712 free_drv_info:
713 	kfree(drv_info);
714 ffa_bus_exit:
715 	arm_ffa_bus_exit();
716 	return ret;
717 }
718 subsys_initcall(ffa_init);
719 
720 static void __exit ffa_exit(void)
721 {
722 	ffa_rxtx_unmap(drv_info->vm_id);
723 	free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
724 	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
725 	kfree(drv_info);
726 	arm_ffa_bus_exit();
727 }
728 module_exit(ffa_exit);
729 
730 MODULE_ALIAS("arm-ffa");
731 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
732 MODULE_DESCRIPTION("Arm FF-A interface driver");
733 MODULE_LICENSE("GPL v2");
734