1/* 2 * Remote Processor Framework 3 * 4 * Copyright(c) 2011 Texas Instruments, Inc. 5 * Copyright(c) 2011 Google, Inc. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * * Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * * Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * * Neither the name Texas Instruments nor the names of its 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35#ifndef REMOTEPROC_H 36#define REMOTEPROC_H 37 38#include <linux/types.h> 39#include <linux/mutex.h> 40#include <linux/virtio.h> 41#include <linux/completion.h> 42#include <linux/idr.h> 43#include <linux/of.h> 44 45/** 46 * struct resource_table - firmware resource table header 47 * @ver: version number 48 * @num: number of resource entries 49 * @reserved: reserved (must be zero) 50 * @offset: array of offsets pointing at the various resource entries 51 * 52 * A resource table is essentially a list of system resources required 53 * by the remote processor. It may also include configuration entries. 54 * If needed, the remote processor firmware should contain this table 55 * as a dedicated ".resource_table" ELF section. 56 * 57 * Some resources entries are mere announcements, where the host is informed 58 * of specific remoteproc configuration. Other entries require the host to 59 * do something (e.g. allocate a system resource). Sometimes a negotiation 60 * is expected, where the firmware requests a resource, and once allocated, 61 * the host should provide back its details (e.g. address of an allocated 62 * memory region). 63 * 64 * The header of the resource table, as expressed by this structure, 65 * contains a version number (should we need to change this format in the 66 * future), the number of available resource entries, and their offsets 67 * in the table. 68 * 69 * Immediately following this header are the resource entries themselves, 70 * each of which begins with a resource entry header (as described below). 71 */ 72struct resource_table { 73 u32 ver; 74 u32 num; 75 u32 reserved[2]; 76 u32 offset[0]; 77} __packed; 78 79/** 80 * struct fw_rsc_hdr - firmware resource entry header 81 * @type: resource type 82 * @data: resource data 83 * 84 * Every resource entry begins with a 'struct fw_rsc_hdr' header providing 85 * its @type. The content of the entry itself will immediately follow 86 * this header, and it should be parsed according to the resource type. 87 */ 88struct fw_rsc_hdr { 89 u32 type; 90 u8 data[0]; 91} __packed; 92 93/** 94 * enum fw_resource_type - types of resource entries 95 * 96 * @RSC_CARVEOUT: request for allocation of a physically contiguous 97 * memory region. 98 * @RSC_DEVMEM: request to iommu_map a memory-based peripheral. 99 * @RSC_TRACE: announces the availability of a trace buffer into which 100 * the remote processor will be writing logs. 101 * @RSC_VDEV: declare support for a virtio device, and serve as its 102 * virtio header. 103 * @RSC_LAST: just keep this one at the end 104 * 105 * For more details regarding a specific resource type, please see its 106 * dedicated structure below. 107 * 108 * Please note that these values are used as indices to the rproc_handle_rsc 109 * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to 110 * check the validity of an index before the lookup table is accessed, so 111 * please update it as needed. 112 */ 113enum fw_resource_type { 114 RSC_CARVEOUT = 0, 115 RSC_DEVMEM = 1, 116 RSC_TRACE = 2, 117 RSC_VDEV = 3, 118 RSC_LAST = 4, 119}; 120 121#define FW_RSC_ADDR_ANY (-1) 122 123/** 124 * struct fw_rsc_carveout - physically contiguous memory request 125 * @da: device address 126 * @pa: physical address 127 * @len: length (in bytes) 128 * @flags: iommu protection flags 129 * @reserved: reserved (must be zero) 130 * @name: human-readable name of the requested memory region 131 * 132 * This resource entry requests the host to allocate a physically contiguous 133 * memory region. 134 * 135 * These request entries should precede other firmware resource entries, 136 * as other entries might request placing other data objects inside 137 * these memory regions (e.g. data/code segments, trace resource entries, ...). 138 * 139 * Allocating memory this way helps utilizing the reserved physical memory 140 * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries 141 * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB 142 * pressure is important; it may have a substantial impact on performance. 143 * 144 * If the firmware is compiled with static addresses, then @da should specify 145 * the expected device address of this memory region. If @da is set to 146 * FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then 147 * overwrite @da with the dynamically allocated address. 148 * 149 * We will always use @da to negotiate the device addresses, even if it 150 * isn't using an iommu. In that case, though, it will obviously contain 151 * physical addresses. 152 * 153 * Some remote processors needs to know the allocated physical address 154 * even if they do use an iommu. This is needed, e.g., if they control 155 * hardware accelerators which access the physical memory directly (this 156 * is the case with OMAP4 for instance). In that case, the host will 157 * overwrite @pa with the dynamically allocated physical address. 158 * Generally we don't want to expose physical addresses if we don't have to 159 * (remote processors are generally _not_ trusted), so we might want to 160 * change this to happen _only_ when explicitly required by the hardware. 161 * 162 * @flags is used to provide IOMMU protection flags, and @name should 163 * (optionally) contain a human readable name of this carveout region 164 * (mainly for debugging purposes). 165 */ 166struct fw_rsc_carveout { 167 u32 da; 168 u32 pa; 169 u32 len; 170 u32 flags; 171 u32 reserved; 172 u8 name[32]; 173} __packed; 174 175/** 176 * struct fw_rsc_devmem - iommu mapping request 177 * @da: device address 178 * @pa: physical address 179 * @len: length (in bytes) 180 * @flags: iommu protection flags 181 * @reserved: reserved (must be zero) 182 * @name: human-readable name of the requested region to be mapped 183 * 184 * This resource entry requests the host to iommu map a physically contiguous 185 * memory region. This is needed in case the remote processor requires 186 * access to certain memory-based peripherals; _never_ use it to access 187 * regular memory. 188 * 189 * This is obviously only needed if the remote processor is accessing memory 190 * via an iommu. 191 * 192 * @da should specify the required device address, @pa should specify 193 * the physical address we want to map, @len should specify the size of 194 * the mapping and @flags is the IOMMU protection flags. As always, @name may 195 * (optionally) contain a human readable name of this mapping (mainly for 196 * debugging purposes). 197 * 198 * Note: at this point we just "trust" those devmem entries to contain valid 199 * physical addresses, but this isn't safe and will be changed: eventually we 200 * want remoteproc implementations to provide us ranges of physical addresses 201 * the firmware is allowed to request, and not allow firmwares to request 202 * access to physical addresses that are outside those ranges. 203 */ 204struct fw_rsc_devmem { 205 u32 da; 206 u32 pa; 207 u32 len; 208 u32 flags; 209 u32 reserved; 210 u8 name[32]; 211} __packed; 212 213/** 214 * struct fw_rsc_trace - trace buffer declaration 215 * @da: device address 216 * @len: length (in bytes) 217 * @reserved: reserved (must be zero) 218 * @name: human-readable name of the trace buffer 219 * 220 * This resource entry provides the host information about a trace buffer 221 * into which the remote processor will write log messages. 222 * 223 * @da specifies the device address of the buffer, @len specifies 224 * its size, and @name may contain a human readable name of the trace buffer. 225 * 226 * After booting the remote processor, the trace buffers are exposed to the 227 * user via debugfs entries (called trace0, trace1, etc..). 228 */ 229struct fw_rsc_trace { 230 u32 da; 231 u32 len; 232 u32 reserved; 233 u8 name[32]; 234} __packed; 235 236/** 237 * struct fw_rsc_vdev_vring - vring descriptor entry 238 * @da: device address 239 * @align: the alignment between the consumer and producer parts of the vring 240 * @num: num of buffers supported by this vring (must be power of two) 241 * @notifyid is a unique rproc-wide notify index for this vring. This notify 242 * index is used when kicking a remote processor, to let it know that this 243 * vring is triggered. 244 * @pa: physical address 245 * 246 * This descriptor is not a resource entry by itself; it is part of the 247 * vdev resource type (see below). 248 * 249 * Note that @da should either contain the device address where 250 * the remote processor is expecting the vring, or indicate that 251 * dynamically allocation of the vring's device address is supported. 252 */ 253struct fw_rsc_vdev_vring { 254 u32 da; 255 u32 align; 256 u32 num; 257 u32 notifyid; 258 u32 pa; 259} __packed; 260 261/** 262 * struct fw_rsc_vdev - virtio device header 263 * @id: virtio device id (as in virtio_ids.h) 264 * @notifyid is a unique rproc-wide notify index for this vdev. This notify 265 * index is used when kicking a remote processor, to let it know that the 266 * status/features of this vdev have changes. 267 * @dfeatures specifies the virtio device features supported by the firmware 268 * @gfeatures is a place holder used by the host to write back the 269 * negotiated features that are supported by both sides. 270 * @config_len is the size of the virtio config space of this vdev. The config 271 * space lies in the resource table immediate after this vdev header. 272 * @status is a place holder where the host will indicate its virtio progress. 273 * @num_of_vrings indicates how many vrings are described in this vdev header 274 * @reserved: reserved (must be zero) 275 * @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'. 276 * 277 * This resource is a virtio device header: it provides information about 278 * the vdev, and is then used by the host and its peer remote processors 279 * to negotiate and share certain virtio properties. 280 * 281 * By providing this resource entry, the firmware essentially asks remoteproc 282 * to statically allocate a vdev upon registration of the rproc (dynamic vdev 283 * allocation is not yet supported). 284 * 285 * Note: unlike virtualization systems, the term 'host' here means 286 * the Linux side which is running remoteproc to control the remote 287 * processors. We use the name 'gfeatures' to comply with virtio's terms, 288 * though there isn't really any virtualized guest OS here: it's the host 289 * which is responsible for negotiating the final features. 290 * Yeah, it's a bit confusing. 291 * 292 * Note: immediately following this structure is the virtio config space for 293 * this vdev (which is specific to the vdev; for more info, read the virtio 294 * spec). the size of the config space is specified by @config_len. 295 */ 296struct fw_rsc_vdev { 297 u32 id; 298 u32 notifyid; 299 u32 dfeatures; 300 u32 gfeatures; 301 u32 config_len; 302 u8 status; 303 u8 num_of_vrings; 304 u8 reserved[2]; 305 struct fw_rsc_vdev_vring vring[0]; 306} __packed; 307 308/** 309 * struct rproc_mem_entry - memory entry descriptor 310 * @va: virtual address 311 * @dma: dma address 312 * @len: length, in bytes 313 * @da: device address 314 * @priv: associated data 315 * @node: list node 316 */ 317struct rproc_mem_entry { 318 void *va; 319 dma_addr_t dma; 320 int len; 321 u32 da; 322 void *priv; 323 struct list_head node; 324}; 325 326struct rproc; 327 328/** 329 * struct rproc_ops - platform-specific device handlers 330 * @start: power on the device and boot it 331 * @stop: power off the device 332 * @kick: kick a virtqueue (virtqueue id given as a parameter) 333 * @da_to_va: optional platform hook to perform address translations 334 */ 335struct rproc_ops { 336 int (*start)(struct rproc *rproc); 337 int (*stop)(struct rproc *rproc); 338 void (*kick)(struct rproc *rproc, int vqid); 339 void * (*da_to_va)(struct rproc *rproc, u64 da, int len); 340}; 341 342/** 343 * enum rproc_state - remote processor states 344 * @RPROC_OFFLINE: device is powered off 345 * @RPROC_SUSPENDED: device is suspended; needs to be woken up to receive 346 * a message. 347 * @RPROC_RUNNING: device is up and running 348 * @RPROC_CRASHED: device has crashed; need to start recovery 349 * @RPROC_DELETED: device is deleted 350 * @RPROC_LAST: just keep this one at the end 351 * 352 * Please note that the values of these states are used as indices 353 * to rproc_state_string, a state-to-name lookup table, 354 * so please keep the two synchronized. @RPROC_LAST is used to check 355 * the validity of an index before the lookup table is accessed, so 356 * please update it as needed too. 357 */ 358enum rproc_state { 359 RPROC_OFFLINE = 0, 360 RPROC_SUSPENDED = 1, 361 RPROC_RUNNING = 2, 362 RPROC_CRASHED = 3, 363 RPROC_DELETED = 4, 364 RPROC_LAST = 5, 365}; 366 367/** 368 * enum rproc_crash_type - remote processor crash types 369 * @RPROC_MMUFAULT: iommu fault 370 * @RPROC_WATCHDOG: watchdog bite 371 * @RPROC_FATAL_ERROR fatal error 372 * 373 * Each element of the enum is used as an array index. So that, the value of 374 * the elements should be always something sane. 375 * 376 * Feel free to add more types when needed. 377 */ 378enum rproc_crash_type { 379 RPROC_MMUFAULT, 380 RPROC_WATCHDOG, 381 RPROC_FATAL_ERROR, 382}; 383 384/** 385 * struct rproc - represents a physical remote processor device 386 * @node: list node of this rproc object 387 * @domain: iommu domain 388 * @name: human readable name of the rproc 389 * @firmware: name of firmware file to be loaded 390 * @priv: private data which belongs to the platform-specific rproc module 391 * @ops: platform-specific start/stop rproc handlers 392 * @dev: virtual device for refcounting and common remoteproc behavior 393 * @fw_ops: firmware-specific handlers 394 * @power: refcount of users who need this rproc powered up 395 * @state: state of the device 396 * @lock: lock which protects concurrent manipulations of the rproc 397 * @dbg_dir: debugfs directory of this rproc device 398 * @traces: list of trace buffers 399 * @num_traces: number of trace buffers 400 * @carveouts: list of physically contiguous memory allocations 401 * @mappings: list of iommu mappings we initiated, needed on shutdown 402 * @bootaddr: address of first instruction to boot rproc with (optional) 403 * @rvdevs: list of remote virtio devices 404 * @subdevs: list of subdevices, to following the running state 405 * @notifyids: idr for dynamically assigning rproc-wide unique notify ids 406 * @index: index of this rproc device 407 * @crash_handler: workqueue for handling a crash 408 * @crash_cnt: crash counter 409 * @crash_comp: completion used to sync crash handler and the rproc reload 410 * @recovery_disabled: flag that state if recovery was disabled 411 * @max_notifyid: largest allocated notify id. 412 * @table_ptr: pointer to the resource table in effect 413 * @cached_table: copy of the resource table 414 * @has_iommu: flag to indicate if remote processor is behind an MMU 415 */ 416struct rproc { 417 struct list_head node; 418 struct iommu_domain *domain; 419 const char *name; 420 char *firmware; 421 void *priv; 422 const struct rproc_ops *ops; 423 struct device dev; 424 const struct rproc_fw_ops *fw_ops; 425 atomic_t power; 426 unsigned int state; 427 struct mutex lock; 428 struct dentry *dbg_dir; 429 struct list_head traces; 430 int num_traces; 431 struct list_head carveouts; 432 struct list_head mappings; 433 u32 bootaddr; 434 struct list_head rvdevs; 435 struct list_head subdevs; 436 struct idr notifyids; 437 int index; 438 struct work_struct crash_handler; 439 unsigned int crash_cnt; 440 struct completion crash_comp; 441 bool recovery_disabled; 442 int max_notifyid; 443 struct resource_table *table_ptr; 444 struct resource_table *cached_table; 445 bool has_iommu; 446 bool auto_boot; 447}; 448 449/** 450 * struct rproc_subdev - subdevice tied to a remoteproc 451 * @node: list node related to the rproc subdevs list 452 * @probe: probe function, called as the rproc is started 453 * @remove: remove function, called as the rproc is stopped 454 */ 455struct rproc_subdev { 456 struct list_head node; 457 458 int (*probe)(struct rproc_subdev *subdev); 459 void (*remove)(struct rproc_subdev *subdev); 460}; 461 462/* we currently support only two vrings per rvdev */ 463 464#define RVDEV_NUM_VRINGS 2 465 466/** 467 * struct rproc_vring - remoteproc vring state 468 * @va: virtual address 469 * @dma: dma address 470 * @len: length, in bytes 471 * @da: device address 472 * @align: vring alignment 473 * @notifyid: rproc-specific unique vring index 474 * @rvdev: remote vdev 475 * @vq: the virtqueue of this vring 476 */ 477struct rproc_vring { 478 void *va; 479 dma_addr_t dma; 480 int len; 481 u32 da; 482 u32 align; 483 int notifyid; 484 struct rproc_vdev *rvdev; 485 struct virtqueue *vq; 486}; 487 488/** 489 * struct rproc_vdev - remoteproc state for a supported virtio device 490 * @refcount: reference counter for the vdev and vring allocations 491 * @subdev: handle for registering the vdev as a rproc subdevice 492 * @id: virtio device id (as in virtio_ids.h) 493 * @node: list node 494 * @rproc: the rproc handle 495 * @vdev: the virio device 496 * @vring: the vrings for this vdev 497 * @rsc_offset: offset of the vdev's resource entry 498 */ 499struct rproc_vdev { 500 struct kref refcount; 501 502 struct rproc_subdev subdev; 503 504 unsigned int id; 505 struct list_head node; 506 struct rproc *rproc; 507 struct virtio_device vdev; 508 struct rproc_vring vring[RVDEV_NUM_VRINGS]; 509 u32 rsc_offset; 510}; 511 512struct rproc *rproc_get_by_phandle(phandle phandle); 513struct rproc *rproc_alloc(struct device *dev, const char *name, 514 const struct rproc_ops *ops, 515 const char *firmware, int len); 516void rproc_put(struct rproc *rproc); 517int rproc_add(struct rproc *rproc); 518int rproc_del(struct rproc *rproc); 519void rproc_free(struct rproc *rproc); 520 521int rproc_boot(struct rproc *rproc); 522void rproc_shutdown(struct rproc *rproc); 523void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type); 524 525static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev) 526{ 527 return container_of(vdev, struct rproc_vdev, vdev); 528} 529 530static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev) 531{ 532 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); 533 534 return rvdev->rproc; 535} 536 537void rproc_add_subdev(struct rproc *rproc, 538 struct rproc_subdev *subdev, 539 int (*probe)(struct rproc_subdev *subdev), 540 void (*remove)(struct rproc_subdev *subdev)); 541 542void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev); 543 544#endif /* REMOTEPROC_H */ 545