1 /*
2 * Copyright (c) 2020-2025, Arm Limited. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #ifndef FFA_SVC_H
8 #define FFA_SVC_H
9
10 #include <stdbool.h>
11
12 #include <lib/smccc.h>
13 #include <lib/utils_def.h>
14 #include <tools_share/uuid.h>
15
16 /* FFA error codes. */
17 #define FFA_ERROR_NOT_SUPPORTED -1
18 #define FFA_ERROR_INVALID_PARAMETER -2
19 #define FFA_ERROR_NO_MEMORY -3
20 #define FFA_ERROR_BUSY -4
21 #define FFA_ERROR_INTERRUPTED -5
22 #define FFA_ERROR_DENIED -6
23 #define FFA_ERROR_RETRY -7
24
25 /* The macros below are used to identify FFA calls from the SMC function ID */
26 #define FFA_FNUM_MIN_VALUE U(0x60)
27 #define FFA_FNUM_MAX_VALUE U(0x90)
28 #define is_ffa_fid(fid) __extension__ ({ \
29 __typeof__(fid) _fid = (fid); \
30 ((GET_SMC_NUM(_fid) >= FFA_FNUM_MIN_VALUE) && \
31 (GET_SMC_NUM(_fid) <= FFA_FNUM_MAX_VALUE)); })
32
33 /* FFA_VERSION helpers */
34 #define FFA_VERSION_MAJOR_SHIFT 16
35 #define FFA_VERSION_MAJOR_MASK U(0x7FFF)
36 #define FFA_VERSION_MINOR_SHIFT 0
37 #define FFA_VERSION_MINOR_MASK U(0xFFFF)
38 #define FFA_VERSION_BIT31_MASK U(0x1u << 31)
39 #define FFA_VERSION_MASK U(0xFFFFFFFF)
40
41 #define FFA_VERSION_MAJOR U(1)
42 #define FFA_VERSION_MINOR U(3)
43
44 #define MAKE_FFA_VERSION(major, minor) \
45 ((((major) & FFA_VERSION_MAJOR_MASK) << FFA_VERSION_MAJOR_SHIFT) | \
46 (((minor) & FFA_VERSION_MINOR_MASK) << FFA_VERSION_MINOR_SHIFT))
47 #define FFA_VERSION_COMPILED MAKE_FFA_VERSION(FFA_VERSION_MAJOR, \
48 FFA_VERSION_MINOR)
49
50 /* FFA_MSG_SEND helpers */
51 #define FFA_MSG_SEND_ATTRS_BLK_SHIFT U(0)
52 #define FFA_MSG_SEND_ATTRS_BLK_MASK U(0x1)
53 #define FFA_MSG_SEND_ATTRS_BLK U(0)
54 #define FFA_MSG_SEND_ATTRS_BLK_NOT U(1)
55 #define FFA_MSG_SEND_ATTRS(blk) \
56 (((blk) & FFA_MSG_SEND_ATTRS_BLK_MASK) \
57 << FFA_MSG_SEND_ATTRS_BLK_SHIFT)
58
59 /* Defines for FF-A framework messages exchanged using direct messages. */
60 #define FFA_FWK_MSG_BIT BIT_32(31)
61 #define FFA_FWK_MSG_MASK U(0xFF)
62 #define FFA_FWK_MSG_PSCI U(0x0)
63
64 /* Defines for FF-A power management messages framework messages. */
65 #define FFA_PM_MSG_WB_REQ U(0x1) /* Warm boot request. */
66 #define FFA_PM_MSG_PM_RESP U(0x2) /* Response to PSCI or warmboot req. */
67
68 /* FF-A warm boot types. */
69 #define FFA_WB_TYPE_S2RAM 0x0
70 #define FFA_WB_TYPE_NOTS2RAM 0x1
71
72 /* Get FFA fastcall std FID from function number */
73 #define FFA_FID(smc_cc, func_num) \
74 ((SMC_TYPE_FAST << FUNCID_TYPE_SHIFT) | \
75 ((smc_cc) << FUNCID_CC_SHIFT) | \
76 (OEN_STD_START << FUNCID_OEN_SHIFT) | \
77 ((func_num) << FUNCID_NUM_SHIFT))
78
79 /* FFA function numbers */
80 #define FFA_FNUM_ERROR U(0x60)
81 #define FFA_FNUM_SUCCESS U(0x61)
82 #define FFA_FNUM_INTERRUPT U(0x62)
83 #define FFA_FNUM_VERSION U(0x63)
84 #define FFA_FNUM_FEATURES U(0x64)
85 #define FFA_FNUM_RX_RELEASE U(0x65)
86 #define FFA_FNUM_RXTX_MAP U(0x66)
87 #define FFA_FNUM_RXTX_UNMAP U(0x67)
88 #define FFA_FNUM_PARTITION_INFO_GET U(0x68)
89 #define FFA_FNUM_ID_GET U(0x69)
90 #define FFA_FNUM_MSG_POLL U(0x6A) /* Legacy FF-A v1.0 */
91 #define FFA_FNUM_MSG_WAIT U(0x6B)
92 #define FFA_FNUM_MSG_YIELD U(0x6C)
93 #define FFA_FNUM_MSG_RUN U(0x6D)
94 #define FFA_FNUM_MSG_SEND U(0x6E) /* Legacy FF-A v1.0 */
95 #define FFA_FNUM_MSG_SEND_DIRECT_REQ U(0x6F)
96 #define FFA_FNUM_MSG_SEND_DIRECT_RESP U(0x70)
97 #define FFA_FNUM_MEM_DONATE U(0x71)
98 #define FFA_FNUM_MEM_LEND U(0x72)
99 #define FFA_FNUM_MEM_SHARE U(0x73)
100 #define FFA_FNUM_MEM_RETRIEVE_REQ U(0x74)
101 #define FFA_FNUM_MEM_RETRIEVE_RESP U(0x75)
102 #define FFA_FNUM_MEM_RELINQUISH U(0x76)
103 #define FFA_FNUM_MEM_RECLAIM U(0x77)
104 #define FFA_FNUM_MEM_FRAG_RX U(0x7A)
105 #define FFA_FNUM_MEM_FRAG_TX U(0x7B)
106 #define FFA_FNUM_NORMAL_WORLD_RESUME U(0x7C)
107
108 /* FF-A v1.1 */
109 #define FFA_FNUM_NOTIFICATION_BITMAP_CREATE U(0x7D)
110 #define FFA_FNUM_NOTIFICATION_BITMAP_DESTROY U(0x7E)
111 #define FFA_FNUM_NOTIFICATION_BIND U(0x7F)
112 #define FFA_FNUM_NOTIFICATION_UNBIND U(0x80)
113 #define FFA_FNUM_NOTIFICATION_SET U(0x81)
114 #define FFA_FNUM_NOTIFICATION_GET U(0x82)
115 #define FFA_FNUM_NOTIFICATION_INFO_GET U(0x83)
116 #define FFA_FNUM_RX_ACQUIRE U(0x84)
117 #define FFA_FNUM_SPM_ID_GET U(0x85)
118 #define FFA_FNUM_MSG_SEND2 U(0x86)
119 #define FFA_FNUM_SECONDARY_EP_REGISTER U(0x87)
120 #define FFA_FNUM_MEM_PERM_GET U(0x88)
121 #define FFA_FNUM_MEM_PERM_SET U(0x89)
122
123 /* FF-A v1.2 */
124 #define FFA_FNUM_PARTITION_INFO_GET_REGS U(0x8B)
125 #define FFA_FNUM_EL3_INTR_HANDLE U(0x8C)
126 #define FFA_FNUM_MSG_SEND_DIRECT_REQ2 U(0x8D)
127 #define FFA_FNUM_MSG_SEND_DIRECT_RESP2 U(0x8E)
128 #define FFA_FNUM_NS_RES_INFO_GET U(0x8F)
129
130 #define FFA_FNUM_CONSOLE_LOG U(0x8A)
131
132 /* FFA SMC32 FIDs */
133 #define FFA_ERROR FFA_FID(SMC_32, FFA_FNUM_ERROR)
134 #define FFA_SUCCESS_SMC32 FFA_FID(SMC_32, FFA_FNUM_SUCCESS)
135 #define FFA_INTERRUPT FFA_FID(SMC_32, FFA_FNUM_INTERRUPT)
136 #define FFA_VERSION FFA_FID(SMC_32, FFA_FNUM_VERSION)
137 #define FFA_FEATURES FFA_FID(SMC_32, FFA_FNUM_FEATURES)
138 #define FFA_RX_RELEASE FFA_FID(SMC_32, FFA_FNUM_RX_RELEASE)
139 #define FFA_RX_ACQUIRE FFA_FID(SMC_32, FFA_FNUM_RX_ACQUIRE)
140 #define FFA_RXTX_MAP_SMC32 FFA_FID(SMC_32, FFA_FNUM_RXTX_MAP)
141 #define FFA_RXTX_UNMAP FFA_FID(SMC_32, FFA_FNUM_RXTX_UNMAP)
142 #define FFA_PARTITION_INFO_GET FFA_FID(SMC_32, FFA_FNUM_PARTITION_INFO_GET)
143 #define FFA_ID_GET FFA_FID(SMC_32, FFA_FNUM_ID_GET)
144 #define FFA_MSG_POLL FFA_FID(SMC_32, FFA_FNUM_MSG_POLL)
145 #define FFA_MSG_WAIT FFA_FID(SMC_32, FFA_FNUM_MSG_WAIT)
146 #define FFA_MSG_YIELD FFA_FID(SMC_32, FFA_FNUM_MSG_YIELD)
147 #define FFA_MSG_RUN FFA_FID(SMC_32, FFA_FNUM_MSG_RUN)
148 #define FFA_MSG_SEND FFA_FID(SMC_32, FFA_FNUM_MSG_SEND)
149 #define FFA_MSG_SEND2 FFA_FID(SMC_32, FFA_FNUM_MSG_SEND2)
150 #define FFA_MSG_SEND_DIRECT_REQ_SMC32 \
151 FFA_FID(SMC_32, FFA_FNUM_MSG_SEND_DIRECT_REQ)
152 #define FFA_MSG_SEND_DIRECT_RESP_SMC32 \
153 FFA_FID(SMC_32, FFA_FNUM_MSG_SEND_DIRECT_RESP)
154 #define FFA_MEM_DONATE_SMC32 FFA_FID(SMC_32, FFA_FNUM_MEM_DONATE)
155 #define FFA_MEM_LEND_SMC32 FFA_FID(SMC_32, FFA_FNUM_MEM_LEND)
156 #define FFA_MEM_SHARE_SMC32 FFA_FID(SMC_32, FFA_FNUM_MEM_SHARE)
157 #define FFA_MEM_RETRIEVE_REQ_SMC32 \
158 FFA_FID(SMC_32, FFA_FNUM_MEM_RETRIEVE_REQ)
159 #define FFA_MEM_RETRIEVE_RESP FFA_FID(SMC_32, FFA_FNUM_MEM_RETRIEVE_RESP)
160 #define FFA_MEM_RELINQUISH FFA_FID(SMC_32, FFA_FNUM_MEM_RELINQUISH)
161 #define FFA_MEM_RECLAIM FFA_FID(SMC_32, FFA_FNUM_MEM_RECLAIM)
162 #define FFA_NOTIFICATION_BITMAP_CREATE \
163 FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_BITMAP_CREATE)
164 #define FFA_NOTIFICATION_BITMAP_DESTROY \
165 FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_BITMAP_DESTROY)
166 #define FFA_NOTIFICATION_BIND FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_BIND)
167 #define FFA_NOTIFICATION_UNBIND FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_UNBIND)
168 #define FFA_NOTIFICATION_SET FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_SET)
169 #define FFA_NOTIFICATION_GET FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_GET)
170 #define FFA_NOTIFICATION_INFO_GET \
171 FFA_FID(SMC_32, FFA_FNUM_NOTIFICATION_INFO_GET)
172 #define FFA_MEM_FRAG_RX FFA_FID(SMC_32, FFA_FNUM_MEM_FRAG_RX)
173 #define FFA_MEM_FRAG_TX FFA_FID(SMC_32, FFA_FNUM_MEM_FRAG_TX)
174 #define FFA_SPM_ID_GET FFA_FID(SMC_32, FFA_FNUM_SPM_ID_GET)
175 #define FFA_NORMAL_WORLD_RESUME FFA_FID(SMC_32, FFA_FNUM_NORMAL_WORLD_RESUME)
176 #define FFA_EL3_INTR_HANDLE FFA_FID(SMC_32, FFA_FNUM_EL3_INTR_HANDLE)
177 #define FFA_MEM_PERM_GET_SMC32 FFA_FID(SMC_32, FFA_FNUM_MEM_PERM_GET)
178 #define FFA_MEM_PERM_SET_SMC32 FFA_FID(SMC_32, FFA_FNUM_MEM_PERM_SET)
179 #define FFA_CONSOLE_LOG_SMC32 FFA_FID(SMC_32, FFA_FNUM_CONSOLE_LOG)
180
181 /* FFA SMC64 FIDs */
182 #define FFA_ERROR_SMC64 FFA_FID(SMC_64, FFA_FNUM_ERROR)
183 #define FFA_SUCCESS_SMC64 FFA_FID(SMC_64, FFA_FNUM_SUCCESS)
184 #define FFA_RXTX_MAP_SMC64 FFA_FID(SMC_64, FFA_FNUM_RXTX_MAP)
185 #define FFA_MSG_SEND_DIRECT_REQ_SMC64 \
186 FFA_FID(SMC_64, FFA_FNUM_MSG_SEND_DIRECT_REQ)
187 #define FFA_MSG_SEND_DIRECT_RESP_SMC64 \
188 FFA_FID(SMC_64, FFA_FNUM_MSG_SEND_DIRECT_RESP)
189 #define FFA_MEM_DONATE_SMC64 FFA_FID(SMC_64, FFA_FNUM_MEM_DONATE)
190 #define FFA_MEM_LEND_SMC64 FFA_FID(SMC_64, FFA_FNUM_MEM_LEND)
191 #define FFA_MEM_SHARE_SMC64 FFA_FID(SMC_64, FFA_FNUM_MEM_SHARE)
192 #define FFA_MEM_RETRIEVE_REQ_SMC64 \
193 FFA_FID(SMC_64, FFA_FNUM_MEM_RETRIEVE_REQ)
194 #define FFA_SECONDARY_EP_REGISTER_SMC64 \
195 FFA_FID(SMC_64, FFA_FNUM_SECONDARY_EP_REGISTER)
196 #define FFA_NOTIFICATION_INFO_GET_SMC64 \
197 FFA_FID(SMC_64, FFA_FNUM_NOTIFICATION_INFO_GET)
198 #define FFA_PARTITION_INFO_GET_REGS_SMC64 \
199 FFA_FID(SMC_64, FFA_FNUM_PARTITION_INFO_GET_REGS)
200 #define FFA_CONSOLE_LOG_SMC64 FFA_FID(SMC_64, FFA_FNUM_CONSOLE_LOG)
201 #define FFA_MSG_SEND_DIRECT_REQ2_SMC64 \
202 FFA_FID(SMC_64, FFA_FNUM_MSG_SEND_DIRECT_REQ2)
203 #define FFA_MSG_SEND_DIRECT_RESP2_SMC64 \
204 FFA_FID(SMC_64, FFA_FNUM_MSG_SEND_DIRECT_RESP2)
205 #define FFA_MEM_PERM_GET_SMC64 FFA_FID(SMC_64, FFA_FNUM_MEM_PERM_GET)
206 #define FFA_MEM_PERM_SET_SMC64 FFA_FID(SMC_64, FFA_FNUM_MEM_PERM_SET)
207 #define FFA_NS_RES_INFO_GET_SMC64 \
208 FFA_FID(SMC_64, FFA_FNUM_NS_RES_INFO_GET)
209
210 /* FF-A v1.3 ALP2 specification. */
211 #define FFA_FNUM_ABORT U(0x90)
212 #define FFA_ABORT_SMC32 FFA_FID(SMC_32, FFA_FNUM_ABORT)
213 #define FFA_ABORT_SMC64 FFA_FID(SMC_64, FFA_FNUM_ABORT)
214 /*
215 * FF-A partition properties values.
216 */
217 #define FFA_PARTITION_DIRECT_REQ_RECV U(1 << 0)
218 #define FFA_PARTITION_DIRECT_REQ_SEND U(1 << 1)
219 #define FFA_PARTITION_INDIRECT_MSG U(1 << 2)
220 #define FFA_PARTITION_VM_CREATED U(1 << 6)
221 #define FFA_PARTITION_VM_DESTROYED U(1 << 7)
222 #define FFA_PARTITION_DIRECT_REQ2_RECV U(1 << 9)
223 #define FFA_PARTITION_DIRECT_REQ2_SEND U(1 << 10)
224
225 /*
226 * "vm-availability-messages" values.
227 */
228 #define FFA_VM_AVAILABILITY_CREATED U(1 << 0)
229 #define FFA_VM_AVAILABILITY_DESTROYED U(1 << 1)
230
231 /*
232 * Reserve a special value for traffic targeted to the Hypervisor or SPM.
233 */
234 #define FFA_TARGET_INFO_MBZ U(0x0)
235
236 /*
237 * Reserve a special value for MBZ parameters.
238 */
239 #define FFA_PARAM_MBZ U(0x0)
240
241 /*
242 * Maximum FF-A endpoint id value
243 */
244 #define FFA_ENDPOINT_ID_MAX U(1 << 16)
245
246 /*
247 * Reserve endpoint id for the SPMD.
248 */
249 #define SPMD_DIRECT_MSG_ENDPOINT_ID U(FFA_ENDPOINT_ID_MAX - 1)
250
251 /* Mask and shift to check valid secure FF-A Endpoint ID. */
252 #define SPMC_SECURE_ID_MASK U(1)
253 #define SPMC_SECURE_ID_SHIFT U(15)
254
255 /*
256 * Partition Count Flag in FFA_PARTITION_INFO_GET.
257 */
258 #define FFA_PARTITION_INFO_GET_COUNT_FLAG_MASK U(1 << 0)
259
260 /*
261 * Mask for source and destination endpoint id in
262 * a direct message request/response.
263 */
264 #define FFA_DIRECT_MSG_ENDPOINT_ID_MASK U(0xffff)
265
266 /*
267 * Bit shift for destination endpoint id in a direct message request/response.
268 */
269 #define FFA_DIRECT_MSG_DESTINATION_SHIFT U(0)
270
271 /*
272 * Bit shift for source endpoint id in a direct message request/response.
273 */
274 #define FFA_DIRECT_MSG_SOURCE_SHIFT U(16)
275
276 /******************************************************************************
277 * ffa_endpoint_destination
278 *****************************************************************************/
ffa_endpoint_destination(unsigned int ep)279 static inline uint16_t ffa_endpoint_destination(unsigned int ep)
280 {
281 return (ep >> FFA_DIRECT_MSG_DESTINATION_SHIFT) &
282 FFA_DIRECT_MSG_ENDPOINT_ID_MASK;
283 }
284
285 /******************************************************************************
286 * ffa_endpoint_source
287 *****************************************************************************/
ffa_endpoint_source(unsigned int ep)288 static inline uint16_t ffa_endpoint_source(unsigned int ep)
289 {
290 return (ep >> FFA_DIRECT_MSG_SOURCE_SHIFT) &
291 FFA_DIRECT_MSG_ENDPOINT_ID_MASK;
292 }
293
294 /******************************************************************************
295 * FF-A helper functions to determine partition ID world.
296 *****************************************************************************/
297
298 /*
299 * Determine if provided ID is in the secure world.
300 */
ffa_is_secure_world_id(uint16_t id)301 static inline bool ffa_is_secure_world_id(uint16_t id)
302 {
303 return ((id >> SPMC_SECURE_ID_SHIFT) & SPMC_SECURE_ID_MASK) == 1;
304 }
305
306 /*
307 * Determine if provided ID is in the normal world.
308 */
ffa_is_normal_world_id(uint16_t id)309 static inline bool ffa_is_normal_world_id(uint16_t id)
310 {
311 return !ffa_is_secure_world_id(id);
312 }
313
314
315 /******************************************************************************
316 * Boot information protocol as per the FF-A v1.1 spec.
317 *****************************************************************************/
318 #define FFA_INIT_DESC_SIGNATURE 0x00000FFA
319
320 /* Boot information type. */
321 #define FFA_BOOT_INFO_TYPE_STD U(0x0)
322 #define FFA_BOOT_INFO_TYPE_IMPL U(0x1)
323
324 #define FFA_BOOT_INFO_TYPE_MASK U(0x1)
325 #define FFA_BOOT_INFO_TYPE_SHIFT U(0x7)
326 #define FFA_BOOT_INFO_TYPE(type) \
327 (((type) & FFA_BOOT_INFO_TYPE_MASK) \
328 << FFA_BOOT_INFO_TYPE_SHIFT)
329
330 /* Boot information identifier. */
331 #define FFA_BOOT_INFO_TYPE_ID_FDT U(0x0)
332 #define FFA_BOOT_INFO_TYPE_ID_HOB U(0x1)
333
334 #define FFA_BOOT_INFO_TYPE_ID_MASK U(0x3F)
335 #define FFA_BOOT_INFO_TYPE_ID_SHIFT U(0x0)
336 #define FFA_BOOT_INFO_TYPE_ID(type) \
337 (((type) & FFA_BOOT_INFO_TYPE_ID_MASK) \
338 << FFA_BOOT_INFO_TYPE_ID_SHIFT)
339
340 /* Format of Flags Name field. */
341 #define FFA_BOOT_INFO_FLAG_NAME_STRING U(0x0)
342 #define FFA_BOOT_INFO_FLAG_NAME_UUID U(0x1)
343
344 #define FFA_BOOT_INFO_FLAG_NAME_MASK U(0x3)
345 #define FFA_BOOT_INFO_FLAG_NAME_SHIFT U(0x0)
346 #define FFA_BOOT_INFO_FLAG_NAME(type) \
347 (((type) & FFA_BOOT_INFO_FLAG_NAME_MASK)\
348 << FFA_BOOT_INFO_FLAG_NAME_SHIFT)
349
350 /* Format of Flags Contents field. */
351 #define FFA_BOOT_INFO_FLAG_CONTENT_ADR U(0x0)
352 #define FFA_BOOT_INFO_FLAG_CONTENT_VAL U(0x1)
353
354 #define FFA_BOOT_INFO_FLAG_CONTENT_MASK U(0x1)
355 #define FFA_BOOT_INFO_FLAG_CONTENT_SHIFT U(0x2)
356 #define FFA_BOOT_INFO_FLAG_CONTENT(content) \
357 (((content) & FFA_BOOT_INFO_FLAG_CONTENT_MASK) \
358 << FFA_BOOT_INFO_FLAG_CONTENT_SHIFT)
359
360 /* Boot information descriptor. */
361 struct ffa_boot_info_desc {
362 uint8_t name[16];
363 uint8_t type;
364 uint8_t reserved;
365 uint16_t flags;
366 uint32_t size_boot_info;
367 uint64_t content;
368 };
369
370 /* Boot information header. */
371 struct ffa_boot_info_header {
372 uint32_t signature; /* 0xFFA */
373 uint32_t version;
374 uint32_t size_boot_info_blob;
375 uint32_t size_boot_info_desc;
376 uint32_t count_boot_info_desc;
377 uint32_t offset_boot_info_desc;
378 uint64_t reserved;
379 };
380
381 /* FF-A Partition Info Get related macros. */
382 #define FFA_PARTITION_INFO_GET_PROPERTIES_V1_0_MASK U(0x7)
383 #define FFA_PARTITION_INFO_GET_EXEC_STATE_SHIFT U(8)
384 #define FFA_PARTITION_INFO_GET_AARCH32_STATE U(0)
385 #define FFA_PARTITION_INFO_GET_AARCH64_STATE U(1)
386
387 /**
388 * Holds information returned for each partition by the FFA_PARTITION_INFO_GET
389 * interface.
390 */
391 struct ffa_partition_info_v1_0 {
392 uint16_t ep_id;
393 uint16_t execution_ctx_count;
394 uint32_t properties;
395 };
396
397 /* Extended structure for FF-A v1.1. */
398 struct ffa_partition_info_v1_1 {
399 uint16_t ep_id;
400 uint16_t execution_ctx_count;
401 uint32_t properties;
402 uint32_t uuid[4];
403 };
404
405 #endif /* FFA_SVC_H */
406