1 // SPDX-License-Identifier: GPL-2.0-only
3 * Arm Firmware Framework for ARMv8-A(FFA) interface driver
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.
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.
17 * [1] https://developer.arm.com/docs/den0077/latest
19 * Copyright (C) 2021 ARM Ltd.
22 #define DRIVER_NAME "ARM FF-A"
23 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
25 #include <linux/arm_ffa.h>
26 #include <linux/bitfield.h>
27 #include <linux/device.h>
29 #include <linux/kernel.h>
30 #include <linux/module.h>
32 #include <linux/scatterlist.h>
33 #include <linux/slab.h>
34 #include <linux/uuid.h>
38 #define FFA_DRIVER_VERSION FFA_VERSION_1_0
39 #define FFA_MIN_VERSION FFA_VERSION_1_0
41 #define SENDER_ID_MASK GENMASK(31, 16)
42 #define RECEIVER_ID_MASK GENMASK(15, 0)
43 #define SENDER_ID(x) ((u16)(FIELD_GET(SENDER_ID_MASK, (x))))
44 #define RECEIVER_ID(x) ((u16)(FIELD_GET(RECEIVER_ID_MASK, (x))))
45 #define PACK_TARGET_INFO(s, r) \
46 (FIELD_PREP(SENDER_ID_MASK, (s)) | FIELD_PREP(RECEIVER_ID_MASK, (r)))
49 * Keeping RX TX buffer size as 4K for now
50 * 64K may be preferred to keep it min a page in 64K PAGE_SIZE config
52 #define RXTX_BUFFER_SIZE SZ_4K
54 static ffa_fn *invoke_ffa_fn;
56 static const int ffa_linux_errmap[] = {
57 /* better than switch case as long as return value is continuous */
58 0, /* FFA_RET_SUCCESS */
59 -EOPNOTSUPP, /* FFA_RET_NOT_SUPPORTED */
60 -EINVAL, /* FFA_RET_INVALID_PARAMETERS */
61 -ENOMEM, /* FFA_RET_NO_MEMORY */
62 -EBUSY, /* FFA_RET_BUSY */
63 -EINTR, /* FFA_RET_INTERRUPTED */
64 -EACCES, /* FFA_RET_DENIED */
65 -EAGAIN, /* FFA_RET_RETRY */
66 -ECANCELED, /* FFA_RET_ABORTED */
69 static inline int ffa_to_linux_errno(int errno)
73 if (err_idx >= 0 && err_idx < ARRAY_SIZE(ffa_linux_errmap))
74 return ffa_linux_errmap[err_idx];
81 struct mutex rx_lock; /* lock to protect Rx buffer */
82 struct mutex tx_lock; /* lock to protect Tx buffer */
88 static struct ffa_drv_info *drv_info;
91 * The driver must be able to support all the versions from the earliest
92 * supported FFA_MIN_VERSION to the latest supported FFA_DRIVER_VERSION.
93 * The specification states that if firmware supports a FFA implementation
94 * that is incompatible with and at a greater version number than specified
95 * by the caller(FFA_DRIVER_VERSION passed as parameter to FFA_VERSION),
96 * it must return the NOT_SUPPORTED error code.
98 static u32 ffa_compatible_version_find(u32 version)
100 u16 major = FFA_MAJOR_VERSION(version), minor = FFA_MINOR_VERSION(version);
101 u16 drv_major = FFA_MAJOR_VERSION(FFA_DRIVER_VERSION);
102 u16 drv_minor = FFA_MINOR_VERSION(FFA_DRIVER_VERSION);
104 if ((major < drv_major) || (major == drv_major && minor <= drv_minor))
107 pr_info("Firmware version higher than driver version, downgrading\n");
108 return FFA_DRIVER_VERSION;
111 static int ffa_version_check(u32 *version)
115 invoke_ffa_fn((ffa_value_t){
116 .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION,
119 if (ver.a0 == FFA_RET_NOT_SUPPORTED) {
120 pr_info("FFA_VERSION returned not supported\n");
124 if (ver.a0 < FFA_MIN_VERSION) {
125 pr_err("Incompatible v%d.%d! Earliest supported v%d.%d\n",
126 FFA_MAJOR_VERSION(ver.a0), FFA_MINOR_VERSION(ver.a0),
127 FFA_MAJOR_VERSION(FFA_MIN_VERSION),
128 FFA_MINOR_VERSION(FFA_MIN_VERSION));
132 pr_info("Driver version %d.%d\n", FFA_MAJOR_VERSION(FFA_DRIVER_VERSION),
133 FFA_MINOR_VERSION(FFA_DRIVER_VERSION));
134 pr_info("Firmware version %d.%d found\n", FFA_MAJOR_VERSION(ver.a0),
135 FFA_MINOR_VERSION(ver.a0));
136 *version = ffa_compatible_version_find(ver.a0);
141 static int ffa_rx_release(void)
145 invoke_ffa_fn((ffa_value_t){
146 .a0 = FFA_RX_RELEASE,
149 if (ret.a0 == FFA_ERROR)
150 return ffa_to_linux_errno((int)ret.a2);
152 /* check for ret.a0 == FFA_RX_RELEASE ? */
157 static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
161 invoke_ffa_fn((ffa_value_t){
162 .a0 = FFA_FN_NATIVE(RXTX_MAP),
163 .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt,
166 if (ret.a0 == FFA_ERROR)
167 return ffa_to_linux_errno((int)ret.a2);
172 static int ffa_rxtx_unmap(u16 vm_id)
176 invoke_ffa_fn((ffa_value_t){
177 .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0),
180 if (ret.a0 == FFA_ERROR)
181 return ffa_to_linux_errno((int)ret.a2);
186 #define PARTITION_INFO_GET_RETURN_COUNT_ONLY BIT(0)
188 /* buffer must be sizeof(struct ffa_partition_info) * num_partitions */
190 __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3,
191 struct ffa_partition_info *buffer, int num_partitions)
193 int idx, count, flags = 0, sz, buf_sz;
194 ffa_value_t partition_info;
196 if (!buffer || !num_partitions) /* Just get the count for now */
197 flags = PARTITION_INFO_GET_RETURN_COUNT_ONLY;
199 mutex_lock(&drv_info->rx_lock);
200 invoke_ffa_fn((ffa_value_t){
201 .a0 = FFA_PARTITION_INFO_GET,
202 .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3,
206 if (partition_info.a0 == FFA_ERROR) {
207 mutex_unlock(&drv_info->rx_lock);
208 return ffa_to_linux_errno((int)partition_info.a2);
211 count = partition_info.a2;
213 if (drv_info->version > FFA_VERSION_1_0) {
214 buf_sz = sz = partition_info.a3;
215 if (sz > sizeof(*buffer))
216 buf_sz = sizeof(*buffer);
218 /* FFA_VERSION_1_0 lacks size in the response */
222 if (buffer && count <= num_partitions)
223 for (idx = 0; idx < count; idx++)
224 memcpy(buffer + idx, drv_info->rx_buffer + idx * sz,
229 mutex_unlock(&drv_info->rx_lock);
234 /* buffer is allocated and caller must free the same if returned count > 0 */
236 ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer)
240 struct ffa_partition_info *pbuf;
242 export_uuid((u8 *)uuid0_4, uuid);
243 count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
244 uuid0_4[3], NULL, 0);
248 pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL);
252 count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
253 uuid0_4[3], pbuf, count);
262 #define VM_ID_MASK GENMASK(15, 0)
263 static int ffa_id_get(u16 *vm_id)
267 invoke_ffa_fn((ffa_value_t){
271 if (id.a0 == FFA_ERROR)
272 return ffa_to_linux_errno((int)id.a2);
274 *vm_id = FIELD_GET(VM_ID_MASK, (id.a2));
279 static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit,
280 struct ffa_send_direct_data *data)
282 u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
286 req_id = FFA_MSG_SEND_DIRECT_REQ;
287 resp_id = FFA_MSG_SEND_DIRECT_RESP;
289 req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ);
290 resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP);
293 invoke_ffa_fn((ffa_value_t){
294 .a0 = req_id, .a1 = src_dst_ids, .a2 = 0,
295 .a3 = data->data0, .a4 = data->data1, .a5 = data->data2,
296 .a6 = data->data3, .a7 = data->data4,
299 while (ret.a0 == FFA_INTERRUPT)
300 invoke_ffa_fn((ffa_value_t){
301 .a0 = FFA_RUN, .a1 = ret.a1,
304 if (ret.a0 == FFA_ERROR)
305 return ffa_to_linux_errno((int)ret.a2);
307 if (ret.a0 == resp_id) {
308 data->data0 = ret.a3;
309 data->data1 = ret.a4;
310 data->data2 = ret.a5;
311 data->data3 = ret.a6;
312 data->data4 = ret.a7;
319 static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
320 u32 frag_len, u32 len, u64 *handle)
324 invoke_ffa_fn((ffa_value_t){
325 .a0 = func_id, .a1 = len, .a2 = frag_len,
326 .a3 = buf, .a4 = buf_sz,
329 while (ret.a0 == FFA_MEM_OP_PAUSE)
330 invoke_ffa_fn((ffa_value_t){
331 .a0 = FFA_MEM_OP_RESUME,
332 .a1 = ret.a1, .a2 = ret.a2,
335 if (ret.a0 == FFA_ERROR)
336 return ffa_to_linux_errno((int)ret.a2);
338 if (ret.a0 == FFA_SUCCESS) {
340 *handle = PACK_HANDLE(ret.a2, ret.a3);
341 } else if (ret.a0 == FFA_MEM_FRAG_RX) {
343 *handle = PACK_HANDLE(ret.a1, ret.a2);
351 static int ffa_mem_next_frag(u64 handle, u32 frag_len)
355 invoke_ffa_fn((ffa_value_t){
356 .a0 = FFA_MEM_FRAG_TX,
357 .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle),
361 while (ret.a0 == FFA_MEM_OP_PAUSE)
362 invoke_ffa_fn((ffa_value_t){
363 .a0 = FFA_MEM_OP_RESUME,
364 .a1 = ret.a1, .a2 = ret.a2,
367 if (ret.a0 == FFA_ERROR)
368 return ffa_to_linux_errno((int)ret.a2);
370 if (ret.a0 == FFA_MEM_FRAG_RX)
372 else if (ret.a0 == FFA_SUCCESS)
379 ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
380 u32 len, u64 *handle, bool first)
383 return ffa_mem_next_frag(*handle, frag_len);
385 return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle);
388 static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
393 num_pages += sg->length / FFA_PAGE_SIZE;
394 } while ((sg = sg_next(sg)));
400 ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
401 struct ffa_mem_ops_args *args)
405 phys_addr_t addr = 0;
406 struct ffa_composite_mem_region *composite;
407 struct ffa_mem_region_addr_range *constituents;
408 struct ffa_mem_region_attributes *ep_mem_access;
409 struct ffa_mem_region *mem_region = buffer;
410 u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg);
412 mem_region->tag = args->tag;
413 mem_region->flags = args->flags;
414 mem_region->sender_id = drv_info->vm_id;
415 mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
416 FFA_MEM_INNER_SHAREABLE;
417 ep_mem_access = &mem_region->ep_mem_access[0];
419 for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
420 ep_mem_access->receiver = args->attrs[idx].receiver;
421 ep_mem_access->attrs = args->attrs[idx].attrs;
422 ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
424 mem_region->ep_count = args->nattrs;
426 composite = buffer + COMPOSITE_OFFSET(args->nattrs);
427 composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
428 composite->addr_range_cnt = num_entries;
430 length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
431 frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
432 if (frag_len > max_fragsize)
435 if (!args->use_txbuf) {
436 addr = virt_to_phys(buffer);
437 buf_sz = max_fragsize / FFA_PAGE_SIZE;
440 constituents = buffer + frag_len;
443 if (frag_len == max_fragsize) {
444 rc = ffa_transmit_fragment(func_id, addr, buf_sz,
446 &args->g_handle, first);
453 constituents = buffer;
456 if ((void *)constituents - buffer > max_fragsize) {
457 pr_err("Memory Region Fragment > Tx Buffer size\n");
461 constituents->address = sg_phys(args->sg);
462 constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
464 frag_len += sizeof(struct ffa_mem_region_addr_range);
465 } while ((args->sg = sg_next(args->sg)));
467 return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
468 length, &args->g_handle, first);
471 static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
476 if (!args->use_txbuf) {
477 buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
481 buffer = drv_info->tx_buffer;
482 mutex_lock(&drv_info->tx_lock);
485 ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
488 mutex_unlock(&drv_info->tx_lock);
490 free_pages_exact(buffer, RXTX_BUFFER_SIZE);
492 return ret < 0 ? ret : 0;
495 static int ffa_memory_reclaim(u64 g_handle, u32 flags)
499 invoke_ffa_fn((ffa_value_t){
500 .a0 = FFA_MEM_RECLAIM,
501 .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle),
505 if (ret.a0 == FFA_ERROR)
506 return ffa_to_linux_errno((int)ret.a2);
511 static int ffa_features(u32 func_feat_id, u32 input_props,
512 u32 *if_props_1, u32 *if_props_2)
516 if (!ARM_SMCCC_IS_FAST_CALL(func_feat_id) && input_props) {
517 pr_err("%s: Invalid Parameters: %x, %x", __func__,
518 func_feat_id, input_props);
519 return ffa_to_linux_errno(FFA_RET_INVALID_PARAMETERS);
522 invoke_ffa_fn((ffa_value_t){
523 .a0 = FFA_FEATURES, .a1 = func_feat_id, .a2 = input_props,
526 if (id.a0 == FFA_ERROR)
527 return ffa_to_linux_errno((int)id.a2);
537 static void ffa_set_up_mem_ops_native_flag(void)
539 if (!ffa_features(FFA_FN_NATIVE(MEM_LEND), 0, NULL, NULL) ||
540 !ffa_features(FFA_FN_NATIVE(MEM_SHARE), 0, NULL, NULL))
541 drv_info->mem_ops_native = true;
544 static u32 ffa_api_version_get(void)
546 return drv_info->version;
549 static int ffa_partition_info_get(const char *uuid_str,
550 struct ffa_partition_info *buffer)
554 struct ffa_partition_info *pbuf;
556 if (uuid_parse(uuid_str, &uuid)) {
557 pr_err("invalid uuid (%s)\n", uuid_str);
561 count = ffa_partition_probe(&uuid, &pbuf);
565 memcpy(buffer, pbuf, sizeof(*pbuf) * count);
570 static void _ffa_mode_32bit_set(struct ffa_device *dev)
572 dev->mode_32bit = true;
575 static void ffa_mode_32bit_set(struct ffa_device *dev)
577 if (drv_info->version > FFA_VERSION_1_0)
580 _ffa_mode_32bit_set(dev);
583 static int ffa_sync_send_receive(struct ffa_device *dev,
584 struct ffa_send_direct_data *data)
586 return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id,
587 dev->mode_32bit, data);
590 static int ffa_memory_share(struct ffa_mem_ops_args *args)
592 if (drv_info->mem_ops_native)
593 return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
595 return ffa_memory_ops(FFA_MEM_SHARE, args);
598 static int ffa_memory_lend(struct ffa_mem_ops_args *args)
600 /* Note that upon a successful MEM_LEND request the caller
601 * must ensure that the memory region specified is not accessed
602 * until a successful MEM_RECALIM call has been made.
603 * On systems with a hypervisor present this will been enforced,
604 * however on systems without a hypervisor the responsibility
605 * falls to the calling kernel driver to prevent access.
607 if (drv_info->mem_ops_native)
608 return ffa_memory_ops(FFA_FN_NATIVE(MEM_LEND), args);
610 return ffa_memory_ops(FFA_MEM_LEND, args);
613 static const struct ffa_info_ops ffa_drv_info_ops = {
614 .api_version_get = ffa_api_version_get,
615 .partition_info_get = ffa_partition_info_get,
618 static const struct ffa_msg_ops ffa_drv_msg_ops = {
619 .mode_32bit_set = ffa_mode_32bit_set,
620 .sync_send_receive = ffa_sync_send_receive,
623 static const struct ffa_mem_ops ffa_drv_mem_ops = {
624 .memory_reclaim = ffa_memory_reclaim,
625 .memory_share = ffa_memory_share,
626 .memory_lend = ffa_memory_lend,
629 static const struct ffa_ops ffa_drv_ops = {
630 .info_ops = &ffa_drv_info_ops,
631 .msg_ops = &ffa_drv_msg_ops,
632 .mem_ops = &ffa_drv_mem_ops,
635 void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid)
638 struct ffa_partition_info *pbuf, *tpbuf;
641 * FF-A v1.1 provides UUID for each partition as part of the discovery
642 * API, the discovered UUID must be populated in the device's UUID and
643 * there is no need to copy the same from the driver table.
645 if (drv_info->version > FFA_VERSION_1_0)
648 count = ffa_partition_probe(uuid, &pbuf);
652 for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++)
653 if (tpbuf->id == ffa_dev->vm_id)
654 uuid_copy(&ffa_dev->uuid, uuid);
658 static void ffa_setup_partitions(void)
662 struct ffa_device *ffa_dev;
663 struct ffa_partition_info *pbuf, *tpbuf;
665 count = ffa_partition_probe(&uuid_null, &pbuf);
667 pr_info("%s: No partitions found, error %d\n", __func__, count);
671 for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) {
672 import_uuid(&uuid, (u8 *)tpbuf->uuid);
674 /* Note that if the UUID will be uuid_null, that will require
675 * ffa_device_match() to find the UUID of this partition id
676 * with help of ffa_device_match_uuid(). FF-A v1.1 and above
677 * provides UUID here for each partition as part of the
678 * discovery API and the same is passed.
680 ffa_dev = ffa_device_register(&uuid, tpbuf->id, &ffa_drv_ops);
682 pr_err("%s: failed to register partition ID 0x%x\n",
683 __func__, tpbuf->id);
687 if (drv_info->version > FFA_VERSION_1_0 &&
688 !(tpbuf->properties & FFA_PARTITION_AARCH64_EXEC))
689 _ffa_mode_32bit_set(ffa_dev);
694 static int __init ffa_init(void)
698 ret = ffa_transport_init(&invoke_ffa_fn);
702 ret = arm_ffa_bus_init();
706 drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
712 ret = ffa_version_check(&drv_info->version);
716 if (ffa_id_get(&drv_info->vm_id)) {
717 pr_err("failed to obtain VM id for self\n");
722 drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
723 if (!drv_info->rx_buffer) {
728 drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
729 if (!drv_info->tx_buffer) {
734 ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer),
735 virt_to_phys(drv_info->rx_buffer),
736 RXTX_BUFFER_SIZE / FFA_PAGE_SIZE);
738 pr_err("failed to register FFA RxTx buffers\n");
742 mutex_init(&drv_info->rx_lock);
743 mutex_init(&drv_info->tx_lock);
745 ffa_setup_partitions();
747 ffa_set_up_mem_ops_native_flag();
751 if (drv_info->tx_buffer)
752 free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
753 free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
760 subsys_initcall(ffa_init);
762 static void __exit ffa_exit(void)
764 ffa_rxtx_unmap(drv_info->vm_id);
765 free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
766 free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
770 module_exit(ffa_exit);
772 MODULE_ALIAS("arm-ffa");
773 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
774 MODULE_DESCRIPTION("Arm FF-A interface driver");
775 MODULE_LICENSE("GPL v2");