aboutsummaryrefslogtreecommitdiff
path: root/include/linux/remoteproc.h
blob: f1ffabb978d3c0618325993b631eaa4c57f7324e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
/*
 * Remote Processor Framework
 *
 * Copyright(c) 2011 Texas Instruments, Inc.
 * Copyright(c) 2011 Google, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the
 *   distribution.
 * * Neither the name Texas Instruments nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef REMOTEPROC_H
#define REMOTEPROC_H

#include <linux/types.h>
#include <linux/kref.h>
#include <linux/klist.h>
#include <linux/mutex.h>
#include <linux/virtio.h>
#include <linux/completion.h>
#include <linux/idr.h>

/**
 * struct resource_table - firmware resource table header
 * @ver: version number
 * @num: number of resource entries
 * @reserved: reserved (must be zero)
 * @offset: array of offsets pointing at the various resource entries
 *
 * A resource table is essentially a list of system resources required
 * by the remote processor. It may also include configuration entries.
 * If needed, the remote processor firmware should contain this table
 * as a dedicated ".resource_table" ELF section.
 *
 * Some resources entries are mere announcements, where the host is informed
 * of specific remoteproc configuration. Other entries require the host to
 * do something (e.g. allocate a system resource). Sometimes a negotiation
 * is expected, where the firmware requests a resource, and once allocated,
 * the host should provide back its details (e.g. address of an allocated
 * memory region).
 *
 * The header of the resource table, as expressed by this structure,
 * contains a version number (should we need to change this format in the
 * future), the number of available resource entries, and their offsets
 * in the table.
 *
 * Immediately following this header are the resource entries themselves,
 * each of which begins with a resource entry header (as described below).
 */
struct resource_table {
	u32 ver;
	u32 num;
	u32 reserved[2];
	u32 offset[0];
} __packed;

/**
 * struct fw_rsc_hdr - firmware resource entry header
 * @type: resource type
 * @data: resource data
 *
 * Every resource entry begins with a 'struct fw_rsc_hdr' header providing
 * its @type. The content of the entry itself will immediately follow
 * this header, and it should be parsed according to the resource type.
 */
struct fw_rsc_hdr {
	u32 type;
	u8 data[0];
} __packed;

/**
 * enum fw_resource_type - types of resource entries
 *
 * @RSC_CARVEOUT:   request for allocation of a physically contiguous
 *		    memory region.
 * @RSC_DEVMEM:     request to iommu_map a memory-based peripheral.
 * @RSC_TRACE:	    announces the availability of a trace buffer into which
 *		    the remote processor will be writing logs.
 * @RSC_VDEV:       declare support for a virtio device, and serve as its
 *		    virtio header.
 * @RSC_LAST:       just keep this one at the end
 *
 * For more details regarding a specific resource type, please see its
 * dedicated structure below.
 *
 * Please note that these values are used as indices to the rproc_handle_rsc
 * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to
 * check the validity of an index before the lookup table is accessed, so
 * please update it as needed.
 */
enum fw_resource_type {
	RSC_CARVEOUT	= 0,
	RSC_DEVMEM	= 1,
	RSC_TRACE	= 2,
	RSC_VDEV	= 3,
	RSC_LAST	= 4,
};

#define FW_RSC_ADDR_ANY (0xFFFFFFFFFFFFFFFF)

/**
 * struct fw_rsc_carveout - physically contiguous memory request
 * @da: device address
 * @pa: physical address
 * @len: length (in bytes)
 * @flags: iommu protection flags
 * @reserved: reserved (must be zero)
 * @name: human-readable name of the requested memory region
 *
 * This resource entry requests the host to allocate a physically contiguous
 * memory region.
 *
 * These request entries should precede other firmware resource entries,
 * as other entries might request placing other data objects inside
 * these memory regions (e.g. data/code segments, trace resource entries, ...).
 *
 * Allocating memory this way helps utilizing the reserved physical memory
 * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
 * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
 * pressure is important; it may have a substantial impact on performance.
 *
 * If the firmware is compiled with static addresses, then @da should specify
 * the expected device address of this memory region. If @da is set to
 * FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then
 * overwrite @da with the dynamically allocated address.
 *
 * We will always use @da to negotiate the device addresses, even if it
 * isn't using an iommu. In that case, though, it will obviously contain
 * physical addresses.
 *
 * Some remote processors needs to know the allocated physical address
 * even if they do use an iommu. This is needed, e.g., if they control
 * hardware accelerators which access the physical memory directly (this
 * is the case with OMAP4 for instance). In that case, the host will
 * overwrite @pa with the dynamically allocated physical address.
 * Generally we don't want to expose physical addresses if we don't have to
 * (remote processors are generally _not_ trusted), so we might want to
 * change this to happen _only_ when explicitly required by the hardware.
 *
 * @flags is used to provide IOMMU protection flags, and @name should
 * (optionally) contain a human readable name of this carveout region
 * (mainly for debugging purposes).
 */
struct fw_rsc_carveout {
	u32 da;
	u32 pa;
	u32 len;
	u32 flags;
	u32 reserved;
	u8 name[32];
} __packed;

/**
 * struct fw_rsc_devmem - iommu mapping request
 * @da: device address
 * @pa: physical address
 * @len: length (in bytes)
 * @flags: iommu protection flags
 * @reserved: reserved (must be zero)
 * @name: human-readable name of the requested region to be mapped
 *
 * This resource entry requests the host to iommu map a physically contiguous
 * memory region. This is needed in case the remote processor requires
 * access to certain memory-based peripherals; _never_ use it to access
 * regular memory.
 *
 * This is obviously only needed if the remote processor is accessing memory
 * via an iommu.
 *
 * @da should specify the required device address, @pa should specify
 * the physical address we want to map, @len should specify the size of
 * the mapping and @flags is the IOMMU protection flags. As always, @name may
 * (optionally) contain a human readable name of this mapping (mainly for
 * debugging purposes).
 *
 * Note: at this point we just "trust" those devmem entries to contain valid
 * physical addresses, but this isn't safe and will be changed: eventually we
 * want remoteproc implementations to provide us ranges of physical addresses
 * the firmware is allowed to request, and not allow firmwares to request
 * access to physical addresses that are outside those ranges.
 */
struct fw_rsc_devmem {
	u32 da;
	u32 pa;
	u32 len;
	u32 flags;
	u32 reserved;
	u8 name[32];
} __packed;

/**
 * struct fw_rsc_trace - trace buffer declaration
 * @da: device address
 * @len: length (in bytes)
 * @reserved: reserved (must be zero)
 * @name: human-readable name of the trace buffer
 *
 * This resource entry provides the host information about a trace buffer
 * into which the remote processor will write log messages.
 *
 * @da specifies the device address of the buffer, @len specifies
 * its size, and @name may contain a human readable name of the trace buffer.
 *
 * After booting the remote processor, the trace buffers are exposed to the
 * user via debugfs entries (called trace0, trace1, etc..).
 */
struct fw_rsc_trace {
	u32 da;
	u32 len;
	u32 reserved;
	u8 name[32];
} __packed;

/**
 * struct fw_rsc_vdev_vring - vring descriptor entry
 * @da: device address
 * @align: the alignment between the consumer and producer parts of the vring
 * @num: num of buffers supported by this vring (must be power of two)
 * @notifyid is a unique rproc-wide notify index for this vring. This notify
 * index is used when kicking a remote processor, to let it know that this
 * vring is triggered.
 * @reserved: reserved (must be zero)
 *
 * This descriptor is not a resource entry by itself; it is part of the
 * vdev resource type (see below).
 *
 * Note that @da should either contain the device address where
 * the remote processor is expecting the vring, or indicate that
 * dynamically allocation of the vring's device address is supported.
 */
struct fw_rsc_vdev_vring {
	u32 da;
	u32 align;
	u32 num;
	u32 notifyid;
	u32 reserved;
} __packed;

/**
 * struct fw_rsc_vdev - virtio device header
 * @id: virtio device id (as in virtio_ids.h)
 * @notifyid is a unique rproc-wide notify index for this vdev. This notify
 * index is used when kicking a remote processor, to let it know that the
 * status/features of this vdev have changes.
 * @dfeatures specifies the virtio device features supported by the firmware
 * @gfeatures is a place holder used by the host to write back the
 * negotiated features that are supported by both sides.
 * @config_len is the size of the virtio config space of this vdev. The config
 * space lies in the resource table immediate after this vdev header.
 * @status is a place holder where the host will indicate its virtio progress.
 * @num_of_vrings indicates how many vrings are described in this vdev header
 * @reserved: reserved (must be zero)
 * @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'.
 *
 * This resource is a virtio device header: it provides information about
 * the vdev, and is then used by the host and its peer remote processors
 * to negotiate and share certain virtio properties.
 *
 * By providing this resource entry, the firmware essentially asks remoteproc
 * to statically allocate a vdev upon registration of the rproc (dynamic vdev
 * allocation is not yet supported).
 *
 * Note: unlike virtualization systems, the term 'host' here means
 * the Linux side which is running remoteproc to control the remote
 * processors. We use the name 'gfeatures' to comply with virtio's terms,
 * though there isn't really any virtualized guest OS here: it's the host
 * which is responsible for negotiating the final features.
 * Yeah, it's a bit confusing.
 *
 * Note: immediately following this structure is the virtio config space for
 * this vdev (which is specific to the vdev; for more info, read the virtio
 * spec). the size of the config space is specified by @config_len.
 */
struct fw_rsc_vdev {
	u32 id;
	u32 notifyid;
	u32 dfeatures;
	u32 gfeatures;
	u32 config_len;
	u8 status;
	u8 num_of_vrings;
	u8 reserved[2];
	struct fw_rsc_vdev_vring vring[0];
} __packed;

/**
 * struct rproc_mem_entry - memory entry descriptor
 * @va:	virtual address
 * @dma: dma address
 * @len: length, in bytes
 * @da: device address
 * @priv: associated data
 * @node: list node
 */
struct rproc_mem_entry {
	void *va;
	dma_addr_t dma;
	int len;
	u32 da;
	void *priv;
	struct list_head node;
};

struct rproc;

/**
 * struct rproc_ops - platform-specific device handlers
 * @start:	power on the device and boot it
 * @stop:	power off the device
 * @kick:	kick a virtqueue (virtqueue id given as a parameter)
 */
struct rproc_ops {
	int (*start)(struct rproc *rproc);
	int (*stop)(struct rproc *rproc);
	void (*kick)(struct rproc *rproc, int vqid);
};

/**
 * enum rproc_state - remote processor states
 * @RPROC_OFFLINE:	device is powered off
 * @RPROC_SUSPENDED:	device is suspended; needs to be woken up to receive
 *			a message.
 * @RPROC_RUNNING:	device is up and running
 * @RPROC_CRASHED:	device has crashed; need to start recovery
 * @RPROC_LAST:		just keep this one at the end
 *
 * Please note that the values of these states are used as indices
 * to rproc_state_string, a state-to-name lookup table,
 * so please keep the two synchronized. @RPROC_LAST is used to check
 * the validity of an index before the lookup table is accessed, so
 * please update it as needed too.
 */
enum rproc_state {
	RPROC_OFFLINE	= 0,
	RPROC_SUSPENDED	= 1,
	RPROC_RUNNING	= 2,
	RPROC_CRASHED	= 3,
	RPROC_LAST	= 4,
};

/**
 * struct rproc - represents a physical remote processor device
 * @node: klist node of this rproc object
 * @domain: iommu domain
 * @name: human readable name of the rproc
 * @firmware: name of firmware file to be loaded
 * @priv: private data which belongs to the platform-specific rproc module
 * @ops: platform-specific start/stop rproc handlers
 * @dev: underlying device
 * @refcount: refcount of users that have a valid pointer to this rproc
 * @power: refcount of users who need this rproc powered up
 * @state: state of the device
 * @lock: lock which protects concurrent manipulations of the rproc
 * @dbg_dir: debugfs directory of this rproc device
 * @traces: list of trace buffers
 * @num_traces: number of trace buffers
 * @carveouts: list of physically contiguous memory allocations
 * @mappings: list of iommu mappings we initiated, needed on shutdown
 * @firmware_loading_complete: marks e/o asynchronous firmware loading
 * @bootaddr: address of first instruction to boot rproc with (optional)
 * @rvdevs: list of remote virtio devices
 * @notifyids: idr for dynamically assigning rproc-wide unique notify ids
 */
struct rproc {
	struct klist_node node;
	struct iommu_domain *domain;
	const char *name;
	const char *firmware;
	void *priv;
	const struct rproc_ops *ops;
	struct device *dev;
	struct kref refcount;
	atomic_t power;
	unsigned int state;
	struct mutex lock;
	struct dentry *dbg_dir;
	struct list_head traces;
	int num_traces;
	struct list_head carveouts;
	struct list_head mappings;
	struct completion firmware_loading_complete;
	u32 bootaddr;
	struct list_head rvdevs;
	struct idr notifyids;
};

/* we currently support only two vrings per rvdev */
#define RVDEV_NUM_VRINGS 2

/**
 * struct rproc_vring - remoteproc vring state
 * @va:	virtual address
 * @dma: dma address
 * @len: length, in bytes
 * @da: device address
 * @align: vring alignment
 * @notifyid: rproc-specific unique vring index
 * @rvdev: remote vdev
 * @vq: the virtqueue of this vring
 */
struct rproc_vring {
	void *va;
	dma_addr_t dma;
	int len;
	u32 da;
	u32 align;
	int notifyid;
	struct rproc_vdev *rvdev;
	struct virtqueue *vq;
};

/**
 * struct rproc_vdev - remoteproc state for a supported virtio device
 * @node: list node
 * @rproc: the rproc handle
 * @vdev: the virio device
 * @vring: the vrings for this vdev
 * @dfeatures: virtio device features
 * @gfeatures: virtio guest features
 */
struct rproc_vdev {
	struct list_head node;
	struct rproc *rproc;
	struct virtio_device vdev;
	struct rproc_vring vring[RVDEV_NUM_VRINGS];
	unsigned long dfeatures;
	unsigned long gfeatures;
};

struct rproc *rproc_get_by_name(const char *name);
void rproc_put(struct rproc *rproc);

struct rproc *rproc_alloc(struct device *dev, const char *name,
				const struct rproc_ops *ops,
				const char *firmware, int len);
void rproc_free(struct rproc *rproc);
int rproc_register(struct rproc *rproc);
int rproc_unregister(struct rproc *rproc);

int rproc_boot(struct rproc *rproc);
void rproc_shutdown(struct rproc *rproc);

static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
{
	return container_of(vdev, struct rproc_vdev, vdev);
}

static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev)
{
	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);

	return rvdev->rproc;
}

#endif /* REMOTEPROC_H */