drivers/firmware/arm_ffa/driver.c

   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 /*
 171  * The driver must be able to support all the versions from the earliest
 172  * supported FFA_MIN_VERSION to the latest supported FFA_DRIVER_VERSION.
 173  * The specification states that if firmware supports a FFA implementation
 174  * that is incompatible with and at a greater version number than specified
 175  * by the caller(FFA_DRIVER_VERSION passed as parameter to FFA_VERSION),
 176  * it must return the NOT_SUPPORTED error code.
 177  */
 178 static u32 ffa_compatible_version_find(u32 version)
 179 {
 180         u16 major = MAJOR_VERSION(version), minor = MINOR_VERSION(version);
 181         u16 drv_major = MAJOR_VERSION(FFA_DRIVER_VERSION);
 182         u16 drv_minor = MINOR_VERSION(FFA_DRIVER_VERSION);
 183
 184         if ((major < drv_major) || (major == drv_major && minor <= drv_minor))
 185                 return version;
 186
 187         pr_info("Firmware version higher than driver version, downgrading\n");
 188         return FFA_DRIVER_VERSION;
 189 }
 190
 191 static int ffa_version_check(u32 *version)
 192 {
 193         ffa_value_t ver;
 194
 195         invoke_ffa_fn((ffa_value_t){
 196                       .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION,
 197                       }, &ver);
 198
 199         if (ver.a0 == FFA_RET_NOT_SUPPORTED) {
 200                 pr_info("FFA_VERSION returned not supported\n");
 201                 return -EOPNOTSUPP;
 202         }
 203
 204         if (ver.a0 < FFA_MIN_VERSION) {
 205                 pr_err("Incompatible v%d.%d! Earliest supported v%d.%d\n",
 206                        MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0),
 207                        MAJOR_VERSION(FFA_MIN_VERSION),
 208                        MINOR_VERSION(FFA_MIN_VERSION));
 209                 return -EINVAL;
 210         }
 211
 212         pr_info("Driver version %d.%d\n", MAJOR_VERSION(FFA_DRIVER_VERSION),
 213                 MINOR_VERSION(FFA_DRIVER_VERSION));
 214         pr_info("Firmware version %d.%d found\n", MAJOR_VERSION(ver.a0),
 215                 MINOR_VERSION(ver.a0));
 216         *version = ffa_compatible_version_find(ver.a0);
 217
 218         return 0;
 219 }
 220
 221 static int ffa_rx_release(void)
 222 {
 223         ffa_value_t ret;
 224
 225         invoke_ffa_fn((ffa_value_t){
 226                       .a0 = FFA_RX_RELEASE,
 227                       }, &ret);
 228
 229         if (ret.a0 == FFA_ERROR)
 230                 return ffa_to_linux_errno((int)ret.a2);
 231
 232         /* check for ret.a0 == FFA_RX_RELEASE ? */
 233
 234         return 0;
 235 }
 236
 237 static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
 238 {
 239         ffa_value_t ret;
 240
 241         invoke_ffa_fn((ffa_value_t){
 242                       .a0 = FFA_FN_NATIVE(RXTX_MAP),
 243                       .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt,
 244                       }, &ret);
 245
 246         if (ret.a0 == FFA_ERROR)
 247                 return ffa_to_linux_errno((int)ret.a2);
 248
 249         return 0;
 250 }
 251
 252 static int ffa_rxtx_unmap(u16 vm_id)
 253 {
 254         ffa_value_t ret;
 255
 256         invoke_ffa_fn((ffa_value_t){
 257                       .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0),
 258                       }, &ret);
 259
 260         if (ret.a0 == FFA_ERROR)
 261                 return ffa_to_linux_errno((int)ret.a2);
 262
 263         return 0;
 264 }
 265
 266 /* buffer must be sizeof(struct ffa_partition_info) * num_partitions */
 267 static int
 268 __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3,
 269                          struct ffa_partition_info *buffer, int num_partitions)
 270 {
 271         int count;
 272         ffa_value_t partition_info;
 273
 274         mutex_lock(&drv_info->rx_lock);
 275         invoke_ffa_fn((ffa_value_t){
 276                       .a0 = FFA_PARTITION_INFO_GET,
 277                       .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3,
 278                       }, &partition_info);
 279
 280         if (partition_info.a0 == FFA_ERROR) {
 281                 mutex_unlock(&drv_info->rx_lock);
 282                 return ffa_to_linux_errno((int)partition_info.a2);
 283         }
 284
 285         count = partition_info.a2;
 286
 287         if (buffer && count <= num_partitions)
 288                 memcpy(buffer, drv_info->rx_buffer, sizeof(*buffer) * count);
 289
 290         ffa_rx_release();
 291
 292         mutex_unlock(&drv_info->rx_lock);
 293
 294         return count;
 295 }
 296
 297 /* buffer is allocated and caller must free the same if returned count > 0 */
 298 static int
 299 ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer)
 300 {
 301         int count;
 302         u32 uuid0_4[4];
 303         struct ffa_partition_info *pbuf;
 304
 305         export_uuid((u8 *)uuid0_4, uuid);
 306         count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
 307                                          uuid0_4[3], NULL, 0);
 308         if (count <= 0)
 309                 return count;
 310
 311         pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL);
 312         if (!pbuf)
 313                 return -ENOMEM;
 314
 315         count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
 316                                          uuid0_4[3], pbuf, count);
 317         if (count <= 0)
 318                 kfree(pbuf);
 319         else
 320                 *buffer = pbuf;
 321
 322         return count;
 323 }
 324
 325 #define VM_ID_MASK      GENMASK(15, 0)
 326 static int ffa_id_get(u16 *vm_id)
 327 {
 328         ffa_value_t id;
 329
 330         invoke_ffa_fn((ffa_value_t){
 331                       .a0 = FFA_ID_GET,
 332                       }, &id);
 333
 334         if (id.a0 == FFA_ERROR)
 335                 return ffa_to_linux_errno((int)id.a2);
 336
 337         *vm_id = FIELD_GET(VM_ID_MASK, (id.a2));
 338
 339         return 0;
 340 }
 341
 342 static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit,
 343                                    struct ffa_send_direct_data *data)
 344 {
 345         u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
 346         ffa_value_t ret;
 347
 348         if (mode_32bit) {
 349                 req_id = FFA_MSG_SEND_DIRECT_REQ;
 350                 resp_id = FFA_MSG_SEND_DIRECT_RESP;
 351         } else {
 352                 req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ);
 353                 resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP);
 354         }
 355
 356         invoke_ffa_fn((ffa_value_t){
 357                       .a0 = req_id, .a1 = src_dst_ids, .a2 = 0,
 358                       .a3 = data->data0, .a4 = data->data1, .a5 = data->data2,
 359                       .a6 = data->data3, .a7 = data->data4,
 360                       }, &ret);
 361
 362         while (ret.a0 == FFA_INTERRUPT)
 363                 invoke_ffa_fn((ffa_value_t){
 364                               .a0 = FFA_RUN, .a1 = ret.a1,
 365                               }, &ret);
 366
 367         if (ret.a0 == FFA_ERROR)
 368                 return ffa_to_linux_errno((int)ret.a2);
 369
 370         if (ret.a0 == resp_id) {
 371                 data->data0 = ret.a3;
 372                 data->data1 = ret.a4;
 373                 data->data2 = ret.a5;
 374                 data->data3 = ret.a6;
 375                 data->data4 = ret.a7;
 376                 return 0;
 377         }
 378
 379         return -EINVAL;
 380 }
 381
 382 static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
 383                               u32 frag_len, u32 len, u64 *handle)
 384 {
 385         ffa_value_t ret;
 386
 387         invoke_ffa_fn((ffa_value_t){
 388                       .a0 = func_id, .a1 = len, .a2 = frag_len,
 389                       .a3 = buf, .a4 = buf_sz,
 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_SUCCESS)
 402                 return -EOPNOTSUPP;
 403
 404         if (handle)
 405                 *handle = PACK_HANDLE(ret.a2, ret.a3);
 406
 407         return frag_len;
 408 }
 409
 410 static int ffa_mem_next_frag(u64 handle, u32 frag_len)
 411 {
 412         ffa_value_t ret;
 413
 414         invoke_ffa_fn((ffa_value_t){
 415                       .a0 = FFA_MEM_FRAG_TX,
 416                       .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle),
 417                       .a3 = frag_len,
 418                       }, &ret);
 419
 420         while (ret.a0 == FFA_MEM_OP_PAUSE)
 421                 invoke_ffa_fn((ffa_value_t){
 422                               .a0 = FFA_MEM_OP_RESUME,
 423                               .a1 = ret.a1, .a2 = ret.a2,
 424                               }, &ret);
 425
 426         if (ret.a0 == FFA_ERROR)
 427                 return ffa_to_linux_errno((int)ret.a2);
 428
 429         if (ret.a0 != FFA_MEM_FRAG_RX)
 430                 return -EOPNOTSUPP;
 431
 432         return ret.a3;
 433 }
 434
 435 static int
 436 ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
 437                       u32 len, u64 *handle, bool first)
 438 {
 439         if (!first)
 440                 return ffa_mem_next_frag(*handle, frag_len);
 441
 442         return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle);
 443 }
 444
 445 static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
 446 {
 447         u32 num_pages = 0;
 448
 449         do {
 450                 num_pages += sg->length / FFA_PAGE_SIZE;
 451         } while ((sg = sg_next(sg)));
 452
 453         return num_pages;
 454 }
 455
 456 static int
 457 ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
 458                        struct ffa_mem_ops_args *args)
 459 {
 460         int rc = 0;
 461         bool first = true;
 462         phys_addr_t addr = 0;
 463         struct ffa_composite_mem_region *composite;
 464         struct ffa_mem_region_addr_range *constituents;
 465         struct ffa_mem_region_attributes *ep_mem_access;
 466         struct ffa_mem_region *mem_region = buffer;
 467         u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg);
 468
 469         mem_region->tag = args->tag;
 470         mem_region->flags = args->flags;
 471         mem_region->sender_id = drv_info->vm_id;
 472         mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
 473                                  FFA_MEM_INNER_SHAREABLE;
 474         ep_mem_access = &mem_region->ep_mem_access[0];
 475
 476         for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
 477                 ep_mem_access->receiver = args->attrs[idx].receiver;
 478                 ep_mem_access->attrs = args->attrs[idx].attrs;
 479                 ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
 480         }
 481         mem_region->ep_count = args->nattrs;
 482
 483         composite = buffer + COMPOSITE_OFFSET(args->nattrs);
 484         composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
 485         composite->addr_range_cnt = num_entries;
 486
 487         length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
 488         frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
 489         if (frag_len > max_fragsize)
 490                 return -ENXIO;
 491
 492         if (!args->use_txbuf) {
 493                 addr = virt_to_phys(buffer);
 494                 buf_sz = max_fragsize / FFA_PAGE_SIZE;
 495         }
 496
 497         constituents = buffer + frag_len;
 498         idx = 0;
 499         do {
 500                 if (frag_len == max_fragsize) {
 501                         rc = ffa_transmit_fragment(func_id, addr, buf_sz,
 502                                                    frag_len, length,
 503                                                    &args->g_handle, first);
 504                         if (rc < 0)
 505                                 return -ENXIO;
 506
 507                         first = false;
 508                         idx = 0;
 509                         frag_len = 0;
 510                         constituents = buffer;
 511                 }
 512
 513                 if ((void *)constituents - buffer > max_fragsize) {
 514                         pr_err("Memory Region Fragment > Tx Buffer size\n");
 515                         return -EFAULT;
 516                 }
 517
 518                 constituents->address = sg_phys(args->sg);
 519                 constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
 520                 constituents++;
 521                 frag_len += sizeof(struct ffa_mem_region_addr_range);
 522         } while ((args->sg = sg_next(args->sg)));
 523
 524         return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
 525                                      length, &args->g_handle, first);
 526 }
 527
 528 static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
 529 {
 530         int ret;
 531         void *buffer;
 532
 533         if (!args->use_txbuf) {
 534                 buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
 535                 if (!buffer)
 536                         return -ENOMEM;
 537         } else {
 538                 buffer = drv_info->tx_buffer;
 539                 mutex_lock(&drv_info->tx_lock);
 540         }
 541
 542         ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
 543
 544         if (args->use_txbuf)
 545                 mutex_unlock(&drv_info->tx_lock);
 546         else
 547                 free_pages_exact(buffer, RXTX_BUFFER_SIZE);
 548
 549         return ret < 0 ? ret : 0;
 550 }
 551
 552 static int ffa_memory_reclaim(u64 g_handle, u32 flags)
 553 {
 554         ffa_value_t ret;
 555
 556         invoke_ffa_fn((ffa_value_t){
 557                       .a0 = FFA_MEM_RECLAIM,
 558                       .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle),
 559                       .a3 = flags,
 560                       }, &ret);
 561
 562         if (ret.a0 == FFA_ERROR)
 563                 return ffa_to_linux_errno((int)ret.a2);
 564
 565         return 0;
 566 }
 567
 568 static u32 ffa_api_version_get(void)
 569 {
 570         return drv_info->version;
 571 }
 572
 573 static int ffa_partition_info_get(const char *uuid_str,
 574                                   struct ffa_partition_info *buffer)
 575 {
 576         int count;
 577         uuid_t uuid;
 578         struct ffa_partition_info *pbuf;
 579
 580         if (uuid_parse(uuid_str, &uuid)) {
 581                 pr_err("invalid uuid (%s)\n", uuid_str);
 582                 return -ENODEV;
 583         }
 584
 585         count = ffa_partition_probe(&uuid_null, &pbuf);
 586         if (count <= 0)
 587                 return -ENOENT;
 588
 589         memcpy(buffer, pbuf, sizeof(*pbuf) * count);
 590         kfree(pbuf);
 591         return 0;
 592 }
 593
 594 static void ffa_mode_32bit_set(struct ffa_device *dev)
 595 {
 596         dev->mode_32bit = true;
 597 }
 598
 599 static int ffa_sync_send_receive(struct ffa_device *dev,
 600                                  struct ffa_send_direct_data *data)
 601 {
 602         return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id,
 603                                        dev->mode_32bit, data);
 604 }
 605
 606 static int
 607 ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args)
 608 {
 609         if (dev->mode_32bit)
 610                 return ffa_memory_ops(FFA_MEM_SHARE, args);
 611
 612         return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
 613 }
 614
 615 static int
 616 ffa_memory_lend(struct ffa_device *dev, struct ffa_mem_ops_args *args)
 617 {
 618         /* Note that upon a successful MEM_LEND request the caller
 619          * must ensure that the memory region specified is not accessed
 620          * until a successful MEM_RECALIM call has been made.
 621          * On systems with a hypervisor present this will been enforced,
 622          * however on systems without a hypervisor the responsibility
 623          * falls to the calling kernel driver to prevent access.
 624          */
 625         if (dev->mode_32bit)
 626                 return ffa_memory_ops(FFA_MEM_LEND, args);
 627
 628         return ffa_memory_ops(FFA_FN_NATIVE(MEM_LEND), args);
 629 }
 630
 631 static const struct ffa_dev_ops ffa_ops = {
 632         .api_version_get = ffa_api_version_get,
 633         .partition_info_get = ffa_partition_info_get,
 634         .mode_32bit_set = ffa_mode_32bit_set,
 635         .sync_send_receive = ffa_sync_send_receive,
 636         .memory_reclaim = ffa_memory_reclaim,
 637         .memory_share = ffa_memory_share,
 638         .memory_lend = ffa_memory_lend,
 639 };
 640
 641 const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
 642 {
 643         if (ffa_device_is_valid(dev))
 644                 return &ffa_ops;
 645
 646         return NULL;
 647 }
 648 EXPORT_SYMBOL_GPL(ffa_dev_ops_get);
 649
 650 void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid)
 651 {
 652         int count, idx;
 653         struct ffa_partition_info *pbuf, *tpbuf;
 654
 655         count = ffa_partition_probe(uuid, &pbuf);
 656         if (count <= 0)
 657                 return;
 658
 659         for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++)
 660                 if (tpbuf->id == ffa_dev->vm_id)
 661                         uuid_copy(&ffa_dev->uuid, uuid);
 662         kfree(pbuf);
 663 }
 664
 665 static void ffa_setup_partitions(void)
 666 {
 667         int count, idx;
 668         struct ffa_device *ffa_dev;
 669         struct ffa_partition_info *pbuf, *tpbuf;
 670
 671         count = ffa_partition_probe(&uuid_null, &pbuf);
 672         if (count <= 0) {
 673                 pr_info("%s: No partitions found, error %d\n", __func__, count);
 674                 return;
 675         }
 676
 677         for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) {
 678                 /* Note that the &uuid_null parameter will require
 679                  * ffa_device_match() to find the UUID of this partition id
 680                  * with help of ffa_device_match_uuid(). Once the FF-A spec
 681                  * is updated to provide correct UUID here for each partition
 682                  * as part of the discovery API, we need to pass the
 683                  * discovered UUID here instead.
 684                  */
 685                 ffa_dev = ffa_device_register(&uuid_null, tpbuf->id);
 686                 if (!ffa_dev) {
 687                         pr_err("%s: failed to register partition ID 0x%x\n",
 688                                __func__, tpbuf->id);
 689                         continue;
 690                 }
 691
 692                 ffa_dev_set_drvdata(ffa_dev, drv_info);
 693         }
 694         kfree(pbuf);
 695 }
 696
 697 static int __init ffa_init(void)
 698 {
 699         int ret;
 700
 701         ret = ffa_transport_init(&invoke_ffa_fn);
 702         if (ret)
 703                 return ret;
 704
 705         ret = arm_ffa_bus_init();
 706         if (ret)
 707                 return ret;
 708
 709         drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
 710         if (!drv_info) {
 711                 ret = -ENOMEM;
 712                 goto ffa_bus_exit;
 713         }
 714
 715         ret = ffa_version_check(&drv_info->version);
 716         if (ret)
 717                 goto free_drv_info;
 718
 719         if (ffa_id_get(&drv_info->vm_id)) {
 720                 pr_err("failed to obtain VM id for self\n");
 721                 ret = -ENODEV;
 722                 goto free_drv_info;
 723         }
 724
 725         drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
 726         if (!drv_info->rx_buffer) {
 727                 ret = -ENOMEM;
 728                 goto free_pages;
 729         }
 730
 731         drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
 732         if (!drv_info->tx_buffer) {
 733                 ret = -ENOMEM;
 734                 goto free_pages;
 735         }
 736
 737         ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer),
 738                            virt_to_phys(drv_info->rx_buffer),
 739                            RXTX_BUFFER_SIZE / FFA_PAGE_SIZE);
 740         if (ret) {
 741                 pr_err("failed to register FFA RxTx buffers\n");
 742                 goto free_pages;
 743         }
 744
 745         mutex_init(&drv_info->rx_lock);
 746         mutex_init(&drv_info->tx_lock);
 747
 748         ffa_setup_partitions();
 749
 750         return 0;
 751 free_pages:
 752         if (drv_info->tx_buffer)
 753                 free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
 754         free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
 755 free_drv_info:
 756         kfree(drv_info);
 757 ffa_bus_exit:
 758         arm_ffa_bus_exit();
 759         return ret;
 760 }
 761 subsys_initcall(ffa_init);
 762
 763 static void __exit ffa_exit(void)
 764 {
 765         ffa_rxtx_unmap(drv_info->vm_id);
 766         free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
 767         free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
 768         kfree(drv_info);
 769         arm_ffa_bus_exit();
 770 }
 771 module_exit(ffa_exit);
 772
 773 MODULE_ALIAS("arm-ffa");
 774 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
 775 MODULE_DESCRIPTION("Arm FF-A interface driver");
 776 MODULE_LICENSE("GPL v2");