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_MMU = 4, 119 RSC_LAST = 5, 120}; 121 122#define FW_RSC_ADDR_ANY (0xFFFFFFFFFFFFFFFF) 123 124/** 125 * struct fw_rsc_carveout - physically contiguous memory request 126 * @da: device address 127 * @pa: physical address 128 * @len: length (in bytes) 129 * @flags: iommu protection flags 130 * @reserved: reserved (must be zero) 131 * @name: human-readable name of the requested memory region 132 * 133 * This resource entry requests the host to allocate a physically contiguous 134 * memory region. 135 * 136 * These request entries should precede other firmware resource entries, 137 * as other entries might request placing other data objects inside 138 * these memory regions (e.g. data/code segments, trace resource entries, ...). 139 * 140 * Allocating memory this way helps utilizing the reserved physical memory 141 * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries 142 * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB 143 * pressure is important; it may have a substantial impact on performance. 144 * 145 * If the firmware is compiled with static addresses, then @da should specify 146 * the expected device address of this memory region. If @da is set to 147 * FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then 148 * overwrite @da with the dynamically allocated address. 149 * 150 * We will always use @da to negotiate the device addresses, even if it 151 * isn't using an iommu. In that case, though, it will obviously contain 152 * physical addresses. 153 * 154 * Some remote processors needs to know the allocated physical address 155 * even if they do use an iommu. This is needed, e.g., if they control 156 * hardware accelerators which access the physical memory directly (this 157 * is the case with OMAP4 for instance). In that case, the host will 158 * overwrite @pa with the dynamically allocated physical address. 159 * Generally we don't want to expose physical addresses if we don't have to 160 * (remote processors are generally _not_ trusted), so we might want to 161 * change this to happen _only_ when explicitly required by the hardware. 162 * 163 * @flags is used to provide IOMMU protection flags, and @name should 164 * (optionally) contain a human readable name of this carveout region 165 * (mainly for debugging purposes). 166 */ 167struct fw_rsc_carveout { 168 u32 da; 169 u32 pa; 170 u32 len; 171 u32 flags; 172 u32 reserved; 173 u8 name[32]; 174} __packed; 175 176/** 177 * struct fw_rsc_devmem - iommu mapping request 178 * @da: device address 179 * @pa: physical address 180 * @len: length (in bytes) 181 * @flags: iommu protection flags 182 * @reserved: reserved (must be zero) 183 * @name: human-readable name of the requested region to be mapped 184 * 185 * This resource entry requests the host to iommu map a physically contiguous 186 * memory region. This is needed in case the remote processor requires 187 * access to certain memory-based peripherals; _never_ use it to access 188 * regular memory. 189 * 190 * This is obviously only needed if the remote processor is accessing memory 191 * via an iommu. 192 * 193 * @da should specify the required device address, @pa should specify 194 * the physical address we want to map, @len should specify the size of 195 * the mapping and @flags is the IOMMU protection flags. As always, @name may 196 * (optionally) contain a human readable name of this mapping (mainly for 197 * debugging purposes). 198 * 199 * Note: at this point we just "trust" those devmem entries to contain valid 200 * physical addresses, but this isn't safe and will be changed: eventually we 201 * want remoteproc implementations to provide us ranges of physical addresses 202 * the firmware is allowed to request, and not allow firmwares to request 203 * access to physical addresses that are outside those ranges. 204 */ 205struct fw_rsc_devmem { 206 u32 da; 207 u32 pa; 208 u32 len; 209 u32 flags; 210 u32 reserved; 211 u8 name[32]; 212} __packed; 213 214/** 215 * struct fw_rsc_trace - trace buffer declaration 216 * @da: device address 217 * @len: length (in bytes) 218 * @reserved: reserved (must be zero) 219 * @name: human-readable name of the trace buffer 220 * 221 * This resource entry provides the host information about a trace buffer 222 * into which the remote processor will write log messages. 223 * 224 * @da specifies the device address of the buffer, @len specifies 225 * its size, and @name may contain a human readable name of the trace buffer. 226 * 227 * After booting the remote processor, the trace buffers are exposed to the 228 * user via debugfs entries (called trace0, trace1, etc..). 229 */ 230struct fw_rsc_trace { 231 u32 da; 232 u32 len; 233 u32 reserved; 234 u8 name[32]; 235} __packed; 236 237/** 238 * struct fw_rsc_vdev_vring - vring descriptor entry 239 * @da: device address 240 * @align: the alignment between the consumer and producer parts of the vring 241 * @num: num of buffers supported by this vring (must be power of two) 242 * @notifyid is a unique rproc-wide notify index for this vring. This notify 243 * index is used when kicking a remote processor, to let it know that this 244 * vring is triggered. 245 * @reserved: reserved (must be zero) 246 * 247 * This descriptor is not a resource entry by itself; it is part of the 248 * vdev resource type (see below). 249 * 250 * Note that @da should either contain the device address where 251 * the remote processor is expecting the vring, or indicate that 252 * dynamically allocation of the vring's device address is supported. 253 */ 254struct fw_rsc_vdev_vring { 255 u32 da; 256 u32 align; 257 u32 num; 258 u32 notifyid; 259 u32 reserved; 260} __packed; 261 262/** 263 * struct fw_rsc_vdev - virtio device header 264 * @id: virtio device id (as in virtio_ids.h) 265 * @notifyid is a unique rproc-wide notify index for this vdev. This notify 266 * index is used when kicking a remote processor, to let it know that the 267 * status/features of this vdev have changes. 268 * @dfeatures specifies the virtio device features supported by the firmware 269 * @gfeatures is a place holder used by the host to write back the 270 * negotiated features that are supported by both sides. 271 * @config_len is the size of the virtio config space of this vdev. The config 272 * space lies in the resource table immediate after this vdev header. 273 * @status is a place holder where the host will indicate its virtio progress. 274 * @num_of_vrings indicates how many vrings are described in this vdev header 275 * @reserved: reserved (must be zero) 276 * @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'. 277 * 278 * This resource is a virtio device header: it provides information about 279 * the vdev, and is then used by the host and its peer remote processors 280 * to negotiate and share certain virtio properties. 281 * 282 * By providing this resource entry, the firmware essentially asks remoteproc 283 * to statically allocate a vdev upon registration of the rproc (dynamic vdev 284 * allocation is not yet supported). 285 * 286 * Note: unlike virtualization systems, the term 'host' here means 287 * the Linux side which is running remoteproc to control the remote 288 * processors. We use the name 'gfeatures' to comply with virtio's terms, 289 * though there isn't really any virtualized guest OS here: it's the host 290 * which is responsible for negotiating the final features. 291 * Yeah, it's a bit confusing. 292 * 293 * Note: immediately following this structure is the virtio config space for 294 * this vdev (which is specific to the vdev; for more info, read the virtio 295 * spec). the size of the config space is specified by @config_len. 296 */ 297struct fw_rsc_vdev { 298 u32 id; 299 u32 notifyid; 300 u32 dfeatures; 301 u32 gfeatures; 302 u32 config_len; 303 u8 status; 304 u8 num_of_vrings; 305 u8 reserved[2]; 306 struct fw_rsc_vdev_vring vring[0]; 307} __packed; 308 309/** 310 * struct rproc_mem_entry - memory entry descriptor 311 * @va: virtual address 312 * @dma: dma address 313 * @len: length, in bytes 314 * @da: device address 315 * @priv: associated data 316 * @node: list node 317 */ 318struct rproc_mem_entry { 319 void *va; 320 dma_addr_t dma; 321 int len; 322 u32 da; 323 void *priv; 324 struct list_head node; 325}; 326 327struct rproc; 328 329/** 330 * struct rproc_ops - platform-specific device handlers 331 * @start: power on the device and boot it 332 * @stop: power off the device 333 * @kick: kick a virtqueue (virtqueue id given as a parameter) 334 * @da_to_va: optional platform hook to perform address translations 335 */ 336struct rproc_ops { 337 int (*start)(struct rproc *rproc); 338 int (*stop)(struct rproc *rproc); 339 void (*kick)(struct rproc *rproc, int vqid); 340 void * (*da_to_va)(struct rproc *rproc, u64 da, int len); 341}; 342 343/** 344 * enum rproc_state - remote processor states 345 * @RPROC_OFFLINE: device is powered off 346 * @RPROC_SUSPENDED: device is suspended; needs to be woken up to receive 347 * a message. 348 * @RPROC_RUNNING: device is up and running 349 * @RPROC_CRASHED: device has crashed; need to start recovery 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_LAST = 4, 364}; 365 366/** 367 * enum rproc_crash_type - remote processor crash types 368 * @RPROC_MMUFAULT: iommu fault 369 * 370 * Each element of the enum is used as an array index. So that, the value of 371 * the elements should be always something sane. 372 * 373 * Feel free to add more types when needed. 374 */ 375enum rproc_crash_type { 376 RPROC_MMUFAULT, 377}; 378 379/** 380 * struct rproc - represents a physical remote processor device 381 * @node: list node of this rproc object 382 * @domain: iommu domain 383 * @name: human readable name of the rproc 384 * @firmware: name of firmware file to be loaded 385 * @priv: private data which belongs to the platform-specific rproc module 386 * @ops: platform-specific start/stop rproc handlers 387 * @dev: virtual device for refcounting and common remoteproc behavior 388 * @fw_ops: firmware-specific handlers 389 * @power: refcount of users who need this rproc powered up 390 * @state: state of the device 391 * @lock: lock which protects concurrent manipulations of the rproc 392 * @dbg_dir: debugfs directory of this rproc device 393 * @traces: list of trace buffers 394 * @num_traces: number of trace buffers 395 * @carveouts: list of physically contiguous memory allocations 396 * @mappings: list of iommu mappings we initiated, needed on shutdown 397 * @firmware_loading_complete: marks e/o asynchronous firmware loading 398 * @bootaddr: address of first instruction to boot rproc with (optional) 399 * @rvdevs: list of remote virtio devices 400 * @notifyids: idr for dynamically assigning rproc-wide unique notify ids 401 * @index: index of this rproc device 402 * @crash_handler: workqueue for handling a crash 403 * @crash_cnt: crash counter 404 * @crash_comp: completion used to sync crash handler and the rproc reload 405 * @recovery_disabled: flag that state if recovery was disabled 406 * @max_notifyid: largest allocated notify id. 407 * @table_ptr: pointer to the resource table in effect 408 * @cached_table: copy of the resource table 409 * @table_csum: checksum of the resource table 410 * @has_iommu: flag to indicate if remote processor is behind an MMU 411 */ 412struct rproc { 413 struct list_head node; 414 struct iommu_domain *domain; 415 const char *name; 416 const char *firmware; 417 void *priv; 418 const struct rproc_ops *ops; 419 struct device dev; 420 const struct rproc_fw_ops *fw_ops; 421 atomic_t power; 422 unsigned int state; 423 struct mutex lock; 424 struct dentry *dbg_dir; 425 struct list_head traces; 426 int num_traces; 427 struct list_head carveouts; 428 struct list_head mappings; 429 struct completion firmware_loading_complete; 430 u32 bootaddr; 431 struct list_head rvdevs; 432 struct idr notifyids; 433 int index; 434 struct work_struct crash_handler; 435 unsigned crash_cnt; 436 struct completion crash_comp; 437 bool recovery_disabled; 438 int max_notifyid; 439 struct resource_table *table_ptr; 440 struct resource_table *cached_table; 441 u32 table_csum; 442 bool has_iommu; 443}; 444 445/* we currently support only two vrings per rvdev */ 446 447#define RVDEV_NUM_VRINGS 2 448 449/** 450 * struct rproc_vring - remoteproc vring state 451 * @va: virtual address 452 * @dma: dma address 453 * @len: length, in bytes 454 * @da: device address 455 * @align: vring alignment 456 * @notifyid: rproc-specific unique vring index 457 * @rvdev: remote vdev 458 * @vq: the virtqueue of this vring 459 */ 460struct rproc_vring { 461 void *va; 462 dma_addr_t dma; 463 int len; 464 u32 da; 465 u32 align; 466 int notifyid; 467 struct rproc_vdev *rvdev; 468 struct virtqueue *vq; 469}; 470 471/** 472 * struct rproc_vdev - remoteproc state for a supported virtio device 473 * @node: list node 474 * @rproc: the rproc handle 475 * @vdev: the virio device 476 * @vring: the vrings for this vdev 477 * @rsc_offset: offset of the vdev's resource entry 478 */ 479struct rproc_vdev { 480 struct list_head node; 481 struct rproc *rproc; 482 struct virtio_device vdev; 483 struct rproc_vring vring[RVDEV_NUM_VRINGS]; 484 u32 rsc_offset; 485}; 486 487struct rproc *rproc_get_by_phandle(phandle phandle); 488struct rproc *rproc_alloc(struct device *dev, const char *name, 489 const struct rproc_ops *ops, 490 const char *firmware, int len); 491void rproc_put(struct rproc *rproc); 492int rproc_add(struct rproc *rproc); 493int rproc_del(struct rproc *rproc); 494 495int rproc_boot(struct rproc *rproc); 496void rproc_shutdown(struct rproc *rproc); 497void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type); 498 499static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev) 500{ 501 return container_of(vdev, struct rproc_vdev, vdev); 502} 503 504static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev) 505{ 506 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); 507 508 return rvdev->rproc; 509} 510 511#endif /* REMOTEPROC_H */ 512