1/*
2 * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
7 * any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12 * more details.
13 *
14 * The full GNU General Public License is included in this distribution in the
15 * file called COPYING.
16 */
17#ifndef LINUX_DMAENGINE_H
18#define LINUX_DMAENGINE_H
19
20#include <linux/device.h>
21#include <linux/err.h>
22#include <linux/uio.h>
23#include <linux/bug.h>
24#include <linux/scatterlist.h>
25#include <linux/bitmap.h>
26#include <linux/types.h>
27#include <asm/page.h>
28
29/**
30 * typedef dma_cookie_t - an opaque DMA cookie
31 *
32 * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
33 */
34typedef s32 dma_cookie_t;
35#define DMA_MIN_COOKIE	1
36
37static inline int dma_submit_error(dma_cookie_t cookie)
38{
39	return cookie < 0 ? cookie : 0;
40}
41
42/**
43 * enum dma_status - DMA transaction status
44 * @DMA_COMPLETE: transaction completed
45 * @DMA_IN_PROGRESS: transaction not yet processed
46 * @DMA_PAUSED: transaction is paused
47 * @DMA_ERROR: transaction failed
48 */
49enum dma_status {
50	DMA_COMPLETE,
51	DMA_IN_PROGRESS,
52	DMA_PAUSED,
53	DMA_ERROR,
54};
55
56/**
57 * enum dma_transaction_type - DMA transaction types/indexes
58 *
59 * Note: The DMA_ASYNC_TX capability is not to be set by drivers.  It is
60 * automatically set as dma devices are registered.
61 */
62enum dma_transaction_type {
63	DMA_MEMCPY,
64	DMA_XOR,
65	DMA_PQ,
66	DMA_XOR_VAL,
67	DMA_PQ_VAL,
68	DMA_INTERRUPT,
69	DMA_SG,
70	DMA_PRIVATE,
71	DMA_ASYNC_TX,
72	DMA_SLAVE,
73	DMA_CYCLIC,
74	DMA_INTERLEAVE,
75/* last transaction type for creation of the capabilities mask */
76	DMA_TX_TYPE_END,
77};
78
79/**
80 * enum dma_transfer_direction - dma transfer mode and direction indicator
81 * @DMA_MEM_TO_MEM: Async/Memcpy mode
82 * @DMA_MEM_TO_DEV: Slave mode & From Memory to Device
83 * @DMA_DEV_TO_MEM: Slave mode & From Device to Memory
84 * @DMA_DEV_TO_DEV: Slave mode & From Device to Device
85 */
86enum dma_transfer_direction {
87	DMA_MEM_TO_MEM,
88	DMA_MEM_TO_DEV,
89	DMA_DEV_TO_MEM,
90	DMA_DEV_TO_DEV,
91	DMA_TRANS_NONE,
92};
93
94/**
95 * Interleaved Transfer Request
96 * ----------------------------
97 * A chunk is collection of contiguous bytes to be transfered.
98 * The gap(in bytes) between two chunks is called inter-chunk-gap(ICG).
99 * ICGs may or maynot change between chunks.
100 * A FRAME is the smallest series of contiguous {chunk,icg} pairs,
101 *  that when repeated an integral number of times, specifies the transfer.
102 * A transfer template is specification of a Frame, the number of times
103 *  it is to be repeated and other per-transfer attributes.
104 *
105 * Practically, a client driver would have ready a template for each
106 *  type of transfer it is going to need during its lifetime and
107 *  set only 'src_start' and 'dst_start' before submitting the requests.
108 *
109 *
110 *  |      Frame-1        |       Frame-2       | ~ |       Frame-'numf'  |
111 *  |====....==.===...=...|====....==.===...=...| ~ |====....==.===...=...|
112 *
113 *    ==  Chunk size
114 *    ... ICG
115 */
116
117/**
118 * struct data_chunk - Element of scatter-gather list that makes a frame.
119 * @size: Number of bytes to read from source.
120 *	  size_dst := fn(op, size_src), so doesn't mean much for destination.
121 * @icg: Number of bytes to jump after last src/dst address of this
122 *	 chunk and before first src/dst address for next chunk.
123 *	 Ignored for dst(assumed 0), if dst_inc is true and dst_sgl is false.
124 *	 Ignored for src(assumed 0), if src_inc is true and src_sgl is false.
125 */
126struct data_chunk {
127	size_t size;
128	size_t icg;
129};
130
131/**
132 * struct dma_interleaved_template - Template to convey DMAC the transfer pattern
133 *	 and attributes.
134 * @src_start: Bus address of source for the first chunk.
135 * @dst_start: Bus address of destination for the first chunk.
136 * @dir: Specifies the type of Source and Destination.
137 * @src_inc: If the source address increments after reading from it.
138 * @dst_inc: If the destination address increments after writing to it.
139 * @src_sgl: If the 'icg' of sgl[] applies to Source (scattered read).
140 *		Otherwise, source is read contiguously (icg ignored).
141 *		Ignored if src_inc is false.
142 * @dst_sgl: If the 'icg' of sgl[] applies to Destination (scattered write).
143 *		Otherwise, destination is filled contiguously (icg ignored).
144 *		Ignored if dst_inc is false.
145 * @numf: Number of frames in this template.
146 * @frame_size: Number of chunks in a frame i.e, size of sgl[].
147 * @sgl: Array of {chunk,icg} pairs that make up a frame.
148 */
149struct dma_interleaved_template {
150	dma_addr_t src_start;
151	dma_addr_t dst_start;
152	enum dma_transfer_direction dir;
153	bool src_inc;
154	bool dst_inc;
155	bool src_sgl;
156	bool dst_sgl;
157	size_t numf;
158	size_t frame_size;
159	struct data_chunk sgl[0];
160};
161
162/**
163 * enum dma_ctrl_flags - DMA flags to augment operation preparation,
164 *  control completion, and communicate status.
165 * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
166 *  this transaction
167 * @DMA_CTRL_ACK - if clear, the descriptor cannot be reused until the client
168 *  acknowledges receipt, i.e. has has a chance to establish any dependency
169 *  chains
170 * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
171 * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
172 * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
173 *  sources that were the result of a previous operation, in the case of a PQ
174 *  operation it continues the calculation with new sources
175 * @DMA_PREP_FENCE - tell the driver that subsequent operations depend
176 *  on the result of this operation
177 */
178enum dma_ctrl_flags {
179	DMA_PREP_INTERRUPT = (1 << 0),
180	DMA_CTRL_ACK = (1 << 1),
181	DMA_PREP_PQ_DISABLE_P = (1 << 2),
182	DMA_PREP_PQ_DISABLE_Q = (1 << 3),
183	DMA_PREP_CONTINUE = (1 << 4),
184	DMA_PREP_FENCE = (1 << 5),
185};
186
187/**
188 * enum sum_check_bits - bit position of pq_check_flags
189 */
190enum sum_check_bits {
191	SUM_CHECK_P = 0,
192	SUM_CHECK_Q = 1,
193};
194
195/**
196 * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
197 * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
198 * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
199 */
200enum sum_check_flags {
201	SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
202	SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
203};
204
205
206/**
207 * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
208 * See linux/cpumask.h
209 */
210typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
211
212/**
213 * struct dma_chan_percpu - the per-CPU part of struct dma_chan
214 * @memcpy_count: transaction counter
215 * @bytes_transferred: byte counter
216 */
217
218struct dma_chan_percpu {
219	/* stats */
220	unsigned long memcpy_count;
221	unsigned long bytes_transferred;
222};
223
224/**
225 * struct dma_chan - devices supply DMA channels, clients use them
226 * @device: ptr to the dma device who supplies this channel, always !%NULL
227 * @cookie: last cookie value returned to client
228 * @completed_cookie: last completed cookie for this channel
229 * @chan_id: channel ID for sysfs
230 * @dev: class device for sysfs
231 * @device_node: used to add this to the device chan list
232 * @local: per-cpu pointer to a struct dma_chan_percpu
233 * @client_count: how many clients are using this channel
234 * @table_count: number of appearances in the mem-to-mem allocation table
235 * @private: private data for certain client-channel associations
236 */
237struct dma_chan {
238	struct dma_device *device;
239	dma_cookie_t cookie;
240	dma_cookie_t completed_cookie;
241
242	/* sysfs */
243	int chan_id;
244	struct dma_chan_dev *dev;
245
246	struct list_head device_node;
247	struct dma_chan_percpu __percpu *local;
248	int client_count;
249	int table_count;
250	void *private;
251};
252
253/**
254 * struct dma_chan_dev - relate sysfs device node to backing channel device
255 * @chan: driver channel device
256 * @device: sysfs device
257 * @dev_id: parent dma_device dev_id
258 * @idr_ref: reference count to gate release of dma_device dev_id
259 */
260struct dma_chan_dev {
261	struct dma_chan *chan;
262	struct device device;
263	int dev_id;
264	atomic_t *idr_ref;
265};
266
267/**
268 * enum dma_slave_buswidth - defines bus width of the DMA slave
269 * device, source or target buses
270 */
271enum dma_slave_buswidth {
272	DMA_SLAVE_BUSWIDTH_UNDEFINED = 0,
273	DMA_SLAVE_BUSWIDTH_1_BYTE = 1,
274	DMA_SLAVE_BUSWIDTH_2_BYTES = 2,
275	DMA_SLAVE_BUSWIDTH_3_BYTES = 3,
276	DMA_SLAVE_BUSWIDTH_4_BYTES = 4,
277	DMA_SLAVE_BUSWIDTH_8_BYTES = 8,
278	DMA_SLAVE_BUSWIDTH_16_BYTES = 16,
279	DMA_SLAVE_BUSWIDTH_32_BYTES = 32,
280	DMA_SLAVE_BUSWIDTH_64_BYTES = 64,
281};
282
283/**
284 * struct dma_slave_config - dma slave channel runtime config
285 * @direction: whether the data shall go in or out on this slave
286 * channel, right now. DMA_MEM_TO_DEV and DMA_DEV_TO_MEM are
287 * legal values. DEPRECATED, drivers should use the direction argument
288 * to the device_prep_slave_sg and device_prep_dma_cyclic functions or
289 * the dir field in the dma_interleaved_template structure.
290 * @src_addr: this is the physical address where DMA slave data
291 * should be read (RX), if the source is memory this argument is
292 * ignored.
293 * @dst_addr: this is the physical address where DMA slave data
294 * should be written (TX), if the source is memory this argument
295 * is ignored.
296 * @src_addr_width: this is the width in bytes of the source (RX)
297 * register where DMA data shall be read. If the source
298 * is memory this may be ignored depending on architecture.
299 * Legal values: 1, 2, 4, 8.
300 * @dst_addr_width: same as src_addr_width but for destination
301 * target (TX) mutatis mutandis.
302 * @src_maxburst: the maximum number of words (note: words, as in
303 * units of the src_addr_width member, not bytes) that can be sent
304 * in one burst to the device. Typically something like half the
305 * FIFO depth on I/O peripherals so you don't overflow it. This
306 * may or may not be applicable on memory sources.
307 * @dst_maxburst: same as src_maxburst but for destination target
308 * mutatis mutandis.
309 * @device_fc: Flow Controller Settings. Only valid for slave channels. Fill
310 * with 'true' if peripheral should be flow controller. Direction will be
311 * selected at Runtime.
312 * @slave_id: Slave requester id. Only valid for slave channels. The dma
313 * slave peripheral will have unique id as dma requester which need to be
314 * pass as slave config.
315 *
316 * This struct is passed in as configuration data to a DMA engine
317 * in order to set up a certain channel for DMA transport at runtime.
318 * The DMA device/engine has to provide support for an additional
319 * callback in the dma_device structure, device_config and this struct
320 * will then be passed in as an argument to the function.
321 *
322 * The rationale for adding configuration information to this struct is as
323 * follows: if it is likely that more than one DMA slave controllers in
324 * the world will support the configuration option, then make it generic.
325 * If not: if it is fixed so that it be sent in static from the platform
326 * data, then prefer to do that.
327 */
328struct dma_slave_config {
329	enum dma_transfer_direction direction;
330	dma_addr_t src_addr;
331	dma_addr_t dst_addr;
332	enum dma_slave_buswidth src_addr_width;
333	enum dma_slave_buswidth dst_addr_width;
334	u32 src_maxburst;
335	u32 dst_maxburst;
336	bool device_fc;
337	unsigned int slave_id;
338};
339
340/**
341 * enum dma_residue_granularity - Granularity of the reported transfer residue
342 * @DMA_RESIDUE_GRANULARITY_DESCRIPTOR: Residue reporting is not support. The
343 *  DMA channel is only able to tell whether a descriptor has been completed or
344 *  not, which means residue reporting is not supported by this channel. The
345 *  residue field of the dma_tx_state field will always be 0.
346 * @DMA_RESIDUE_GRANULARITY_SEGMENT: Residue is updated after each successfully
347 *  completed segment of the transfer (For cyclic transfers this is after each
348 *  period). This is typically implemented by having the hardware generate an
349 *  interrupt after each transferred segment and then the drivers updates the
350 *  outstanding residue by the size of the segment. Another possibility is if
351 *  the hardware supports scatter-gather and the segment descriptor has a field
352 *  which gets set after the segment has been completed. The driver then counts
353 *  the number of segments without the flag set to compute the residue.
354 * @DMA_RESIDUE_GRANULARITY_BURST: Residue is updated after each transferred
355 *  burst. This is typically only supported if the hardware has a progress
356 *  register of some sort (E.g. a register with the current read/write address
357 *  or a register with the amount of bursts/beats/bytes that have been
358 *  transferred or still need to be transferred).
359 */
360enum dma_residue_granularity {
361	DMA_RESIDUE_GRANULARITY_DESCRIPTOR = 0,
362	DMA_RESIDUE_GRANULARITY_SEGMENT = 1,
363	DMA_RESIDUE_GRANULARITY_BURST = 2,
364};
365
366/* struct dma_slave_caps - expose capabilities of a slave channel only
367 *
368 * @src_addr_widths: bit mask of src addr widths the channel supports
369 * @dst_addr_widths: bit mask of dstn addr widths the channel supports
370 * @directions: bit mask of slave direction the channel supported
371 * 	since the enum dma_transfer_direction is not defined as bits for each
372 * 	type of direction, the dma controller should fill (1 << <TYPE>) and same
373 * 	should be checked by controller as well
374 * @cmd_pause: true, if pause and thereby resume is supported
375 * @cmd_terminate: true, if terminate cmd is supported
376 * @residue_granularity: granularity of the reported transfer residue
377 */
378struct dma_slave_caps {
379	u32 src_addr_widths;
380	u32 dst_addr_widths;
381	u32 directions;
382	bool cmd_pause;
383	bool cmd_terminate;
384	enum dma_residue_granularity residue_granularity;
385};
386
387static inline const char *dma_chan_name(struct dma_chan *chan)
388{
389	return dev_name(&chan->dev->device);
390}
391
392void dma_chan_cleanup(struct kref *kref);
393
394/**
395 * typedef dma_filter_fn - callback filter for dma_request_channel
396 * @chan: channel to be reviewed
397 * @filter_param: opaque parameter passed through dma_request_channel
398 *
399 * When this optional parameter is specified in a call to dma_request_channel a
400 * suitable channel is passed to this routine for further dispositioning before
401 * being returned.  Where 'suitable' indicates a non-busy channel that
402 * satisfies the given capability mask.  It returns 'true' to indicate that the
403 * channel is suitable.
404 */
405typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
406
407typedef void (*dma_async_tx_callback)(void *dma_async_param);
408
409struct dmaengine_unmap_data {
410	u8 map_cnt;
411	u8 to_cnt;
412	u8 from_cnt;
413	u8 bidi_cnt;
414	struct device *dev;
415	struct kref kref;
416	size_t len;
417	dma_addr_t addr[0];
418};
419
420/**
421 * struct dma_async_tx_descriptor - async transaction descriptor
422 * ---dma generic offload fields---
423 * @cookie: tracking cookie for this transaction, set to -EBUSY if
424 *	this tx is sitting on a dependency list
425 * @flags: flags to augment operation preparation, control completion, and
426 * 	communicate status
427 * @phys: physical address of the descriptor
428 * @chan: target channel for this operation
429 * @tx_submit: accept the descriptor, assign ordered cookie and mark the
430 * descriptor pending. To be pushed on .issue_pending() call
431 * @callback: routine to call after this operation is complete
432 * @callback_param: general parameter to pass to the callback routine
433 * ---async_tx api specific fields---
434 * @next: at completion submit this descriptor
435 * @parent: pointer to the next level up in the dependency chain
436 * @lock: protect the parent and next pointers
437 */
438struct dma_async_tx_descriptor {
439	dma_cookie_t cookie;
440	enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */
441	dma_addr_t phys;
442	struct dma_chan *chan;
443	dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
444	dma_async_tx_callback callback;
445	void *callback_param;
446	struct dmaengine_unmap_data *unmap;
447#ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
448	struct dma_async_tx_descriptor *next;
449	struct dma_async_tx_descriptor *parent;
450	spinlock_t lock;
451#endif
452};
453
454#ifdef CONFIG_DMA_ENGINE
455static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
456				 struct dmaengine_unmap_data *unmap)
457{
458	kref_get(&unmap->kref);
459	tx->unmap = unmap;
460}
461
462struct dmaengine_unmap_data *
463dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
464void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
465#else
466static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
467				 struct dmaengine_unmap_data *unmap)
468{
469}
470static inline struct dmaengine_unmap_data *
471dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
472{
473	return NULL;
474}
475static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap)
476{
477}
478#endif
479
480static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx)
481{
482	if (tx->unmap) {
483		dmaengine_unmap_put(tx->unmap);
484		tx->unmap = NULL;
485	}
486}
487
488#ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
489static inline void txd_lock(struct dma_async_tx_descriptor *txd)
490{
491}
492static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
493{
494}
495static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
496{
497	BUG();
498}
499static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
500{
501}
502static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
503{
504}
505static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
506{
507	return NULL;
508}
509static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
510{
511	return NULL;
512}
513
514#else
515static inline void txd_lock(struct dma_async_tx_descriptor *txd)
516{
517	spin_lock_bh(&txd->lock);
518}
519static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
520{
521	spin_unlock_bh(&txd->lock);
522}
523static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
524{
525	txd->next = next;
526	next->parent = txd;
527}
528static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
529{
530	txd->parent = NULL;
531}
532static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
533{
534	txd->next = NULL;
535}
536static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
537{
538	return txd->parent;
539}
540static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
541{
542	return txd->next;
543}
544#endif
545
546/**
547 * struct dma_tx_state - filled in to report the status of
548 * a transfer.
549 * @last: last completed DMA cookie
550 * @used: last issued DMA cookie (i.e. the one in progress)
551 * @residue: the remaining number of bytes left to transmit
552 *	on the selected transfer for states DMA_IN_PROGRESS and
553 *	DMA_PAUSED if this is implemented in the driver, else 0
554 */
555struct dma_tx_state {
556	dma_cookie_t last;
557	dma_cookie_t used;
558	u32 residue;
559};
560
561/**
562 * struct dma_device - info on the entity supplying DMA services
563 * @chancnt: how many DMA channels are supported
564 * @privatecnt: how many DMA channels are requested by dma_request_channel
565 * @channels: the list of struct dma_chan
566 * @global_node: list_head for global dma_device_list
567 * @cap_mask: one or more dma_capability flags
568 * @max_xor: maximum number of xor sources, 0 if no capability
569 * @max_pq: maximum number of PQ sources and PQ-continue capability
570 * @copy_align: alignment shift for memcpy operations
571 * @xor_align: alignment shift for xor operations
572 * @pq_align: alignment shift for pq operations
573 * @dev_id: unique device ID
574 * @dev: struct device reference for dma mapping api
575 * @src_addr_widths: bit mask of src addr widths the device supports
576 * @dst_addr_widths: bit mask of dst addr widths the device supports
577 * @directions: bit mask of slave direction the device supports since
578 * 	the enum dma_transfer_direction is not defined as bits for
579 * 	each type of direction, the dma controller should fill (1 <<
580 * 	<TYPE>) and same should be checked by controller as well
581 * @residue_granularity: granularity of the transfer residue reported
582 *	by tx_status
583 * @device_alloc_chan_resources: allocate resources and return the
584 *	number of allocated descriptors
585 * @device_free_chan_resources: release DMA channel's resources
586 * @device_prep_dma_memcpy: prepares a memcpy operation
587 * @device_prep_dma_xor: prepares a xor operation
588 * @device_prep_dma_xor_val: prepares a xor validation operation
589 * @device_prep_dma_pq: prepares a pq operation
590 * @device_prep_dma_pq_val: prepares a pqzero_sum operation
591 * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
592 * @device_prep_slave_sg: prepares a slave dma operation
593 * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio.
594 *	The function takes a buffer of size buf_len. The callback function will
595 *	be called after period_len bytes have been transferred.
596 * @device_prep_interleaved_dma: Transfer expression in a generic way.
597 * @device_config: Pushes a new configuration to a channel, return 0 or an error
598 *	code
599 * @device_pause: Pauses any transfer happening on a channel. Returns
600 *	0 or an error code
601 * @device_resume: Resumes any transfer on a channel previously
602 *	paused. Returns 0 or an error code
603 * @device_terminate_all: Aborts all transfers on a channel. Returns 0
604 *	or an error code
605 * @device_tx_status: poll for transaction completion, the optional
606 *	txstate parameter can be supplied with a pointer to get a
607 *	struct with auxiliary transfer status information, otherwise the call
608 *	will just return a simple status code
609 * @device_issue_pending: push pending transactions to hardware
610 */
611struct dma_device {
612
613	unsigned int chancnt;
614	unsigned int privatecnt;
615	struct list_head channels;
616	struct list_head global_node;
617	dma_cap_mask_t  cap_mask;
618	unsigned short max_xor;
619	unsigned short max_pq;
620	u8 copy_align;
621	u8 xor_align;
622	u8 pq_align;
623	#define DMA_HAS_PQ_CONTINUE (1 << 15)
624
625	int dev_id;
626	struct device *dev;
627
628	u32 src_addr_widths;
629	u32 dst_addr_widths;
630	u32 directions;
631	enum dma_residue_granularity residue_granularity;
632
633	int (*device_alloc_chan_resources)(struct dma_chan *chan);
634	void (*device_free_chan_resources)(struct dma_chan *chan);
635
636	struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
637		struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
638		size_t len, unsigned long flags);
639	struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
640		struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
641		unsigned int src_cnt, size_t len, unsigned long flags);
642	struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
643		struct dma_chan *chan, dma_addr_t *src,	unsigned int src_cnt,
644		size_t len, enum sum_check_flags *result, unsigned long flags);
645	struct dma_async_tx_descriptor *(*device_prep_dma_pq)(
646		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
647		unsigned int src_cnt, const unsigned char *scf,
648		size_t len, unsigned long flags);
649	struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)(
650		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
651		unsigned int src_cnt, const unsigned char *scf, size_t len,
652		enum sum_check_flags *pqres, unsigned long flags);
653	struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
654		struct dma_chan *chan, unsigned long flags);
655	struct dma_async_tx_descriptor *(*device_prep_dma_sg)(
656		struct dma_chan *chan,
657		struct scatterlist *dst_sg, unsigned int dst_nents,
658		struct scatterlist *src_sg, unsigned int src_nents,
659		unsigned long flags);
660
661	struct dma_async_tx_descriptor *(*device_prep_slave_sg)(
662		struct dma_chan *chan, struct scatterlist *sgl,
663		unsigned int sg_len, enum dma_transfer_direction direction,
664		unsigned long flags, void *context);
665	struct dma_async_tx_descriptor *(*device_prep_dma_cyclic)(
666		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
667		size_t period_len, enum dma_transfer_direction direction,
668		unsigned long flags);
669	struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
670		struct dma_chan *chan, struct dma_interleaved_template *xt,
671		unsigned long flags);
672
673	int (*device_config)(struct dma_chan *chan,
674			     struct dma_slave_config *config);
675	int (*device_pause)(struct dma_chan *chan);
676	int (*device_resume)(struct dma_chan *chan);
677	int (*device_terminate_all)(struct dma_chan *chan);
678
679	enum dma_status (*device_tx_status)(struct dma_chan *chan,
680					    dma_cookie_t cookie,
681					    struct dma_tx_state *txstate);
682	void (*device_issue_pending)(struct dma_chan *chan);
683};
684
685static inline int dmaengine_slave_config(struct dma_chan *chan,
686					  struct dma_slave_config *config)
687{
688	if (chan->device->device_config)
689		return chan->device->device_config(chan, config);
690
691	return -ENOSYS;
692}
693
694static inline bool is_slave_direction(enum dma_transfer_direction direction)
695{
696	return (direction == DMA_MEM_TO_DEV) || (direction == DMA_DEV_TO_MEM);
697}
698
699static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single(
700	struct dma_chan *chan, dma_addr_t buf, size_t len,
701	enum dma_transfer_direction dir, unsigned long flags)
702{
703	struct scatterlist sg;
704	sg_init_table(&sg, 1);
705	sg_dma_address(&sg) = buf;
706	sg_dma_len(&sg) = len;
707
708	return chan->device->device_prep_slave_sg(chan, &sg, 1,
709						  dir, flags, NULL);
710}
711
712static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
713	struct dma_chan *chan, struct scatterlist *sgl,	unsigned int sg_len,
714	enum dma_transfer_direction dir, unsigned long flags)
715{
716	return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
717						  dir, flags, NULL);
718}
719
720#ifdef CONFIG_RAPIDIO_DMA_ENGINE
721struct rio_dma_ext;
722static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
723	struct dma_chan *chan, struct scatterlist *sgl,	unsigned int sg_len,
724	enum dma_transfer_direction dir, unsigned long flags,
725	struct rio_dma_ext *rio_ext)
726{
727	return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
728						  dir, flags, rio_ext);
729}
730#endif
731
732static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
733		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
734		size_t period_len, enum dma_transfer_direction dir,
735		unsigned long flags)
736{
737	return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
738						period_len, dir, flags);
739}
740
741static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma(
742		struct dma_chan *chan, struct dma_interleaved_template *xt,
743		unsigned long flags)
744{
745	return chan->device->device_prep_interleaved_dma(chan, xt, flags);
746}
747
748static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
749		struct dma_chan *chan,
750		struct scatterlist *dst_sg, unsigned int dst_nents,
751		struct scatterlist *src_sg, unsigned int src_nents,
752		unsigned long flags)
753{
754	return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents,
755			src_sg, src_nents, flags);
756}
757
758static inline int dmaengine_terminate_all(struct dma_chan *chan)
759{
760	if (chan->device->device_terminate_all)
761		return chan->device->device_terminate_all(chan);
762
763	return -ENOSYS;
764}
765
766static inline int dmaengine_pause(struct dma_chan *chan)
767{
768	if (chan->device->device_pause)
769		return chan->device->device_pause(chan);
770
771	return -ENOSYS;
772}
773
774static inline int dmaengine_resume(struct dma_chan *chan)
775{
776	if (chan->device->device_resume)
777		return chan->device->device_resume(chan);
778
779	return -ENOSYS;
780}
781
782static inline enum dma_status dmaengine_tx_status(struct dma_chan *chan,
783	dma_cookie_t cookie, struct dma_tx_state *state)
784{
785	return chan->device->device_tx_status(chan, cookie, state);
786}
787
788static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc)
789{
790	return desc->tx_submit(desc);
791}
792
793static inline bool dmaengine_check_align(u8 align, size_t off1, size_t off2, size_t len)
794{
795	size_t mask;
796
797	if (!align)
798		return true;
799	mask = (1 << align) - 1;
800	if (mask & (off1 | off2 | len))
801		return false;
802	return true;
803}
804
805static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1,
806				       size_t off2, size_t len)
807{
808	return dmaengine_check_align(dev->copy_align, off1, off2, len);
809}
810
811static inline bool is_dma_xor_aligned(struct dma_device *dev, size_t off1,
812				      size_t off2, size_t len)
813{
814	return dmaengine_check_align(dev->xor_align, off1, off2, len);
815}
816
817static inline bool is_dma_pq_aligned(struct dma_device *dev, size_t off1,
818				     size_t off2, size_t len)
819{
820	return dmaengine_check_align(dev->pq_align, off1, off2, len);
821}
822
823static inline void
824dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
825{
826	dma->max_pq = maxpq;
827	if (has_pq_continue)
828		dma->max_pq |= DMA_HAS_PQ_CONTINUE;
829}
830
831static inline bool dmaf_continue(enum dma_ctrl_flags flags)
832{
833	return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
834}
835
836static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
837{
838	enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;
839
840	return (flags & mask) == mask;
841}
842
843static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
844{
845	return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
846}
847
848static inline unsigned short dma_dev_to_maxpq(struct dma_device *dma)
849{
850	return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
851}
852
853/* dma_maxpq - reduce maxpq in the face of continued operations
854 * @dma - dma device with PQ capability
855 * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
856 *
857 * When an engine does not support native continuation we need 3 extra
858 * source slots to reuse P and Q with the following coefficients:
859 * 1/ {00} * P : remove P from Q', but use it as a source for P'
860 * 2/ {01} * Q : use Q to continue Q' calculation
861 * 3/ {00} * Q : subtract Q from P' to cancel (2)
862 *
863 * In the case where P is disabled we only need 1 extra source:
864 * 1/ {01} * Q : use Q to continue Q' calculation
865 */
866static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
867{
868	if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
869		return dma_dev_to_maxpq(dma);
870	else if (dmaf_p_disabled_continue(flags))
871		return dma_dev_to_maxpq(dma) - 1;
872	else if (dmaf_continue(flags))
873		return dma_dev_to_maxpq(dma) - 3;
874	BUG();
875}
876
877/* --- public DMA engine API --- */
878
879#ifdef CONFIG_DMA_ENGINE
880void dmaengine_get(void);
881void dmaengine_put(void);
882#else
883static inline void dmaengine_get(void)
884{
885}
886static inline void dmaengine_put(void)
887{
888}
889#endif
890
891#ifdef CONFIG_ASYNC_TX_DMA
892#define async_dmaengine_get()	dmaengine_get()
893#define async_dmaengine_put()	dmaengine_put()
894#ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
895#define async_dma_find_channel(type) dma_find_channel(DMA_ASYNC_TX)
896#else
897#define async_dma_find_channel(type) dma_find_channel(type)
898#endif /* CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH */
899#else
900static inline void async_dmaengine_get(void)
901{
902}
903static inline void async_dmaengine_put(void)
904{
905}
906static inline struct dma_chan *
907async_dma_find_channel(enum dma_transaction_type type)
908{
909	return NULL;
910}
911#endif /* CONFIG_ASYNC_TX_DMA */
912void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
913				  struct dma_chan *chan);
914
915static inline void async_tx_ack(struct dma_async_tx_descriptor *tx)
916{
917	tx->flags |= DMA_CTRL_ACK;
918}
919
920static inline void async_tx_clear_ack(struct dma_async_tx_descriptor *tx)
921{
922	tx->flags &= ~DMA_CTRL_ACK;
923}
924
925static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx)
926{
927	return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK;
928}
929
930#define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask))
931static inline void
932__dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
933{
934	set_bit(tx_type, dstp->bits);
935}
936
937#define dma_cap_clear(tx, mask) __dma_cap_clear((tx), &(mask))
938static inline void
939__dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
940{
941	clear_bit(tx_type, dstp->bits);
942}
943
944#define dma_cap_zero(mask) __dma_cap_zero(&(mask))
945static inline void __dma_cap_zero(dma_cap_mask_t *dstp)
946{
947	bitmap_zero(dstp->bits, DMA_TX_TYPE_END);
948}
949
950#define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
951static inline int
952__dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
953{
954	return test_bit(tx_type, srcp->bits);
955}
956
957#define for_each_dma_cap_mask(cap, mask) \
958	for_each_set_bit(cap, mask.bits, DMA_TX_TYPE_END)
959
960/**
961 * dma_async_issue_pending - flush pending transactions to HW
962 * @chan: target DMA channel
963 *
964 * This allows drivers to push copies to HW in batches,
965 * reducing MMIO writes where possible.
966 */
967static inline void dma_async_issue_pending(struct dma_chan *chan)
968{
969	chan->device->device_issue_pending(chan);
970}
971
972/**
973 * dma_async_is_tx_complete - poll for transaction completion
974 * @chan: DMA channel
975 * @cookie: transaction identifier to check status of
976 * @last: returns last completed cookie, can be NULL
977 * @used: returns last issued cookie, can be NULL
978 *
979 * If @last and @used are passed in, upon return they reflect the driver
980 * internal state and can be used with dma_async_is_complete() to check
981 * the status of multiple cookies without re-checking hardware state.
982 */
983static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
984	dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
985{
986	struct dma_tx_state state;
987	enum dma_status status;
988
989	status = chan->device->device_tx_status(chan, cookie, &state);
990	if (last)
991		*last = state.last;
992	if (used)
993		*used = state.used;
994	return status;
995}
996
997/**
998 * dma_async_is_complete - test a cookie against chan state
999 * @cookie: transaction identifier to test status of
1000 * @last_complete: last know completed transaction
1001 * @last_used: last cookie value handed out
1002 *
1003 * dma_async_is_complete() is used in dma_async_is_tx_complete()
1004 * the test logic is separated for lightweight testing of multiple cookies
1005 */
1006static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
1007			dma_cookie_t last_complete, dma_cookie_t last_used)
1008{
1009	if (last_complete <= last_used) {
1010		if ((cookie <= last_complete) || (cookie > last_used))
1011			return DMA_COMPLETE;
1012	} else {
1013		if ((cookie <= last_complete) && (cookie > last_used))
1014			return DMA_COMPLETE;
1015	}
1016	return DMA_IN_PROGRESS;
1017}
1018
1019static inline void
1020dma_set_tx_state(struct dma_tx_state *st, dma_cookie_t last, dma_cookie_t used, u32 residue)
1021{
1022	if (st) {
1023		st->last = last;
1024		st->used = used;
1025		st->residue = residue;
1026	}
1027}
1028
1029#ifdef CONFIG_DMA_ENGINE
1030struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
1031enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
1032enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
1033void dma_issue_pending_all(void);
1034struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
1035					dma_filter_fn fn, void *fn_param);
1036struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
1037						  const char *name);
1038struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
1039void dma_release_channel(struct dma_chan *chan);
1040int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps);
1041#else
1042static inline struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type)
1043{
1044	return NULL;
1045}
1046static inline enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
1047{
1048	return DMA_COMPLETE;
1049}
1050static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
1051{
1052	return DMA_COMPLETE;
1053}
1054static inline void dma_issue_pending_all(void)
1055{
1056}
1057static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
1058					      dma_filter_fn fn, void *fn_param)
1059{
1060	return NULL;
1061}
1062static inline struct dma_chan *dma_request_slave_channel_reason(
1063					struct device *dev, const char *name)
1064{
1065	return ERR_PTR(-ENODEV);
1066}
1067static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
1068							 const char *name)
1069{
1070	return NULL;
1071}
1072static inline void dma_release_channel(struct dma_chan *chan)
1073{
1074}
1075static inline int dma_get_slave_caps(struct dma_chan *chan,
1076				     struct dma_slave_caps *caps)
1077{
1078	return -ENXIO;
1079}
1080#endif
1081
1082/* --- DMA device --- */
1083
1084int dma_async_device_register(struct dma_device *device);
1085void dma_async_device_unregister(struct dma_device *device);
1086void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
1087struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
1088struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
1089#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
1090#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
1091	__dma_request_slave_channel_compat(&(mask), x, y, dev, name)
1092
1093static inline struct dma_chan
1094*__dma_request_slave_channel_compat(const dma_cap_mask_t *mask,
1095				  dma_filter_fn fn, void *fn_param,
1096				  struct device *dev, char *name)
1097{
1098	struct dma_chan *chan;
1099
1100	chan = dma_request_slave_channel(dev, name);
1101	if (chan)
1102		return chan;
1103
1104	return __dma_request_channel(mask, fn, fn_param);
1105}
1106#endif /* DMAENGINE_H */
1107