xref: /illumos-gate/usr/src/uts/common/sys/ddidmareq.h (revision 87c723434df4be9c0f7ef119567cb6e2da776a36)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 /*
25  * Copyright 2012 Garrett D'Amore <garrett@damore.org>.  All rights reserved.
26  */
27 
28 #ifndef	_SYS_DDIDMAREQ_H
29 #define	_SYS_DDIDMAREQ_H
30 
31 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 /*
36  * Memory Objects
37  *
38  * Definitions of structures that can describe
39  * an object that can be mapped for DMA.
40  */
41 
42 /*
43  * Structure describing a virtual address
44  */
45 struct v_address {
46 	caddr_t		v_addr;		/* base virtual address */
47 	struct	as	*v_as;		/* pointer to address space */
48 	void 		*v_priv;	/* priv data for shadow I/O */
49 };
50 
51 /*
52  * Structure describing a page-based address
53  */
54 struct pp_address {
55 	/*
56 	 * A pointer to a circularly linked list of page structures.
57 	 */
58 	struct page *pp_pp;
59 	uint_t pp_offset;	/* offset within first page */
60 };
61 
62 /*
63  * Structure to describe a physical memory address.
64  */
65 struct phy_address {
66 	ulong_t	p_addr;		/* base physical address */
67 	ulong_t	p_memtype;	/* memory type */
68 };
69 
70 /*
71  * Structure to describe an array DVMA addresses.
72  * Under normal circumstances, dv_nseg will be 1.
73  * dvs_start is always page aligned.
74  */
75 struct dvma_address {
76 	size_t dv_off;
77 	size_t dv_nseg;
78 	struct dvmaseg {
79 		uint64_t dvs_start;
80 		size_t dvs_len;
81 	} *dv_seg;
82 };
83 
84 /*
85  * A union of all of the above structures.
86  *
87  * This union describes the relationship between
88  * the kind of an address description and an object.
89  */
90 typedef union {
91 	struct v_address virt_obj;	/* Some virtual address		*/
92 	struct pp_address pp_obj;	/* Some page-based address	*/
93 	struct phy_address phys_obj;	/* Some physical address	*/
94 	struct dvma_address dvma_obj;
95 } ddi_dma_aobj_t;
96 
97 /*
98  * DMA object types - used to select how the object
99  * being mapped is being addressed by the IU.
100  */
101 typedef enum {
102 	DMA_OTYP_VADDR = 0,	/* enforce starting value of zero */
103 	DMA_OTYP_PAGES,
104 	DMA_OTYP_PADDR,
105 	DMA_OTYP_BUFVADDR,
106 	DMA_OTYP_DVADDR
107 } ddi_dma_atyp_t;
108 
109 /*
110  * A compact package to describe an object that is to be mapped for DMA.
111  */
112 typedef struct {
113 	uint_t		dmao_size;	/* size, in bytes, of the object */
114 	ddi_dma_atyp_t	dmao_type;	/* type of object */
115 	ddi_dma_aobj_t	dmao_obj;	/* the object described */
116 } ddi_dma_obj_t;
117 
118 /*
119  * DMA addressing limits.
120  *
121  * This structure describes the constraints that a particular device's
122  * DMA engine has to its parent so that the parent may correctly set
123  * things up for a DMA mapping. Each parent may in turn modify the
124  * constraints listed in a DMA request structure in order to describe
125  * to its parent any changed or additional constraints. The rules
126  * are that each parent may modify a constraint in order to further
127  * constrain things (e.g., picking a more limited address range than
128  * that permitted by the child), but that the parent may not ignore
129  * a child's constraints.
130  *
131  * A particular constraint that we do *not* address is whether or not
132  * a requested mapping is too large for a DMA engine's counter to
133  * correctly track. It is still up to each driver to explicitly handle
134  * transfers that are too large for its own hardware to deal with directly.
135  *
136  * The mapping routines that are cognizant of this structure will
137  * copy any user defined limits structure if they need to modify
138  * the fields (as alluded to above).
139  *
140  * A note as to how to define constraints:
141  *
142  * How you define the constraints for your device depends on how you
143  * define your device. For example, you may have an SBus card with a
144  * device on it that address only the bottom 16mb of virtual DMA space.
145  * However, if the card also has ancillary circuitry that pulls the high 8
146  * bits of address lines high, the more correct expression for your device
147  * is that it address [0xff000000..0xffffffff] rather than [0..0x00ffffff].
148  */
149 #if defined(__sparc)
150 typedef struct ddi_dma_lim {
151 
152 	/*
153 	 * Low range of 32 bit addressing capability.
154 	 */
155 	uint_t	dlim_addr_lo;
156 
157 	/*
158 	 * Upper inclusive bound of addressing capability. It is an
159 	 * inclusive boundary limit to allow for the addressing range
160 	 * [0..0xffffffff] to be specified in preference to [0..0].
161 	 */
162 	uint_t	dlim_addr_hi;
163 
164 	/*
165 	 * Inclusive upper bound with which The DMA engine's counter acts as
166 	 * a register.
167 	 *
168 	 * This handles the case where an upper portion of a DMA address
169 	 * register is a latch instead of being a full 32 bit register
170 	 * (e.g., the upper 8 bits may remain constant while the lower
171 	 * 24 bits are the real address register).
172 	 *
173 	 * This essentially gives a hint about segment limitations
174 	 * to the mapping routines.
175 	 */
176 	uint_t	dlim_cntr_max;
177 
178 	/*
179 	 * DMA burst sizes.
180 	 *
181 	 * At the time of a mapping request, this tag defines the possible
182 	 * DMA burst cycle sizes that the requestor's DMA engine can
183 	 * emit. The format of the data is binary encoding of burst sizes
184 	 * assumed to be powers of two. That is, if a DMA engine is capable
185 	 * of doing 1, 2, 4 and 16 byte transfers, the encoding would be 0x17.
186 	 *
187 	 * As the mapping request is handled by intervening nexi, the
188 	 * burstsizes value may be modified. Prior to enabling DMA for
189 	 * the specific device, the driver that owns the DMA engine should
190 	 * check (via ddi_dma_burstsizes(9F)) what the allowed burstsizes
191 	 * have become and program their DMA engine appropriately.
192 	 */
193 	uint_t	dlim_burstsizes;
194 
195 	/*
196 	 * Minimum effective DMA transfer size, in units of bytes.
197 	 *
198 	 * This value specifies the minimum effective granularity of the
199 	 * DMA engine. It is distinct from dlim_burtsizes in that it
200 	 * describes the minimum amount of access a DMA transfer will
201 	 * effect. dlim_burtsizes describes in what electrical fashion
202 	 * the DMA engine might perform its accesses, while dlim_minxfer
203 	 * describes the minimum amount of memory that can be touched by
204 	 * the DMA transfer.
205 	 *
206 	 * As the mapping request is handled by intervening nexi, the
207 	 * dlim_minxfer value may be modifed contingent upon the presence
208 	 * (and use) of I/O caches and DMA write buffers in between the
209 	 * DMA engine and the object that DMA is being performed on.
210 	 *
211 	 */
212 	uint_t	dlim_minxfer;
213 
214 	/*
215 	 * Expected average data rate for this DMA engine
216 	 * while transferring data.
217 	 *
218 	 * This is used as a hint for a number of operations that might
219 	 * want to know the possible optimal latency requirements of this
220 	 * device. A value of zero will be interpreted as a 'do not care'.
221 	 */
222 	uint_t	dlim_dmaspeed;
223 
224 } ddi_dma_lim_t;
225 
226 #elif defined(__x86)
227 
228 /*
229  * values for dlim_minxfer
230  */
231 #define	DMA_UNIT_8  1
232 #define	DMA_UNIT_16 2
233 #define	DMA_UNIT_32 4
234 
235 /*
236  * Version number
237  */
238 #define	DMALIM_VER0	((0x86000000) + 0)
239 
240 typedef struct ddi_dma_lim {
241 
242 	/*
243 	 * Low range of 32 bit addressing capability.
244 	 */
245 	uint_t	dlim_addr_lo;
246 
247 	/*
248 	 * Upper Inclusive bound of 32 bit addressing capability.
249 	 *
250 	 * The ISA nexus restricts this to 0x00ffffff, since this bus has
251 	 * only 24 address lines.  This enforces the 16 Mb address limitation.
252 	 * The EISA nexus restricts this to 0xffffffff.
253 	 */
254 	uint_t	dlim_addr_hi;
255 
256 	/*
257 	 * DMA engine counter not used; set to 0
258 	 */
259 	uint_t	dlim_cntr_max;
260 
261 	/*
262 	 *  DMA burst sizes not used; set to 1
263 	 */
264 	uint_t	dlim_burstsizes;
265 
266 	/*
267 	 * Minimum effective DMA transfer size.
268 	 *
269 	 * This value specifies the minimum effective granularity of the
270 	 * DMA engine. It is distinct from dlim_burstsizes in that it
271 	 * describes the minimum amount of access a DMA transfer will
272 	 * effect. dlim_burstsizes describes in what electrical fashion
273 	 * the DMA engine might perform its accesses, while dlim_minxfer
274 	 * describes the minimum amount of memory that can be touched by
275 	 * the DMA transfer.
276 	 *
277 	 * This value also implies the required address alignment.
278 	 * The number of bytes transferred is assumed to be
279 	 * 	dlim_minxfer * (DMA engine count)
280 	 *
281 	 * It should be set to DMA_UNIT_8, DMA_UNIT_16, or DMA_UNIT_32.
282 	 */
283 	uint_t	dlim_minxfer;
284 
285 	/*
286 	 * Expected average data rate for this DMA engine
287 	 * while transferring data.
288 	 *
289 	 * This is used as a hint for a number of operations that might
290 	 * want to know the possible optimal latency requirements of this
291 	 * device. A value of zero will be interpreted as a 'do not care'.
292 	 */
293 	uint_t	dlim_dmaspeed;
294 
295 
296 	/*
297 	 * Version number of this structure
298 	 */
299 	uint_t	dlim_version;	/* = 0x86 << 24 + 0 */
300 
301 	/*
302 	 * Inclusive upper bound with which the DMA engine's Address acts as
303 	 * a register.
304 	 * This handles the case where an upper portion of a DMA address
305 	 * register is a latch instead of being a full 32 bit register
306 	 * (e.g., the upper 16 bits remain constant while the lower 16 bits
307 	 * are incremented for each DMA transfer).
308 	 *
309 	 * The ISA nexus restricts only 3rd-party DMA requests to 0x0000ffff,
310 	 * since the ISA DMA engine has a 16-bit register for low address and
311 	 * an 8-bit latch for high address.  This enforces the first 64 Kb
312 	 * limitation (address boundary).
313 	 * The EISA nexus restricts only 3rd-party DMA requests to 0xffffffff.
314 	 */
315 	uint_t	dlim_adreg_max;
316 
317 	/*
318 	 * Maximum transfer count that the DMA engine can handle.
319 	 *
320 	 * The ISA nexus restricts only 3rd-party DMA requests to 0x0000ffff,
321 	 * since the ISA DMA engine has a 16-bit register for counting.
322 	 * This enforces the other 64 Kb limitation (count size).
323 	 * The EISA nexus restricts only 3rd-party DMA requests to 0x00ffffff,
324 	 * since the EISA DMA engine has a 24-bit register for counting.
325 	 *
326 	 * This transfer count limitation is a per segment limitation.
327 	 * It can also be used to restrict the size of segments.
328 	 *
329 	 * This is used as a bit mask, so it must be a power of 2, minus 1.
330 	 */
331 	uint_t	dlim_ctreg_max;
332 
333 	/*
334 	 * Granularity of DMA transfer, in units of bytes.
335 	 *
336 	 * Breakup sizes must be multiples of this value.
337 	 * If no scatter/gather capabilty is specified, then the size of
338 	 * each DMA transfer must be a multiple of this value.
339 	 *
340 	 * If there is scatter/gather capability, then a single cookie cannot
341 	 * be smaller in size than the minimum xfer value, and may be less
342 	 * than the granularity value.  The total transfer length of the
343 	 * scatter/gather list should be a multiple of the granularity value;
344 	 * use dlim_sgllen to specify the length of the scatter/gather list.
345 	 *
346 	 * This value should be equal to the sector size of the device.
347 	 */
348 	uint_t	dlim_granular;
349 
350 	/*
351 	 * Length of scatter/gather list
352 	 *
353 	 * This value specifies the number of segments or cookies that a DMA
354 	 * engine can consume in one i/o request to the device.  For 3rd-party
355 	 * DMA that uses the bus nexus this should be set to 1.  Devices with
356 	 * 1st-party DMA capability should specify the number of entries in
357 	 * its scatter/gather list.  The breakup routine will ensure that each
358 	 * group of dlim_sgllen cookies (within a DMA window) will have a
359 	 * total transfer length that is a multiple of dlim_granular.
360 	 *
361 	 *	< 0  :  tbd
362 	 *	= 0  :  breakup is for PIO.
363 	 *	= 1  :  breakup is for DMA engine with no scatter/gather
364 	 *		capability.
365 	 *	>= 2 :  breakup is for DMA engine with scatter/gather
366 	 *		capability; value is max number of entries in list.
367 	 *
368 	 * Note that this list length is not dependent on the DMA window
369 	 * size.  The size of the DMA window is based on resources consumed,
370 	 * such as intermediate buffers.  Several s/g lists may exist within
371 	 * a window.  But the end of a window does imply the end of the s/g
372 	 * list.
373 	 */
374 	short	dlim_sgllen;
375 
376 	/*
377 	 * Size of device i/o request
378 	 *
379 	 * This value indicates the maximum number of bytes the device
380 	 * can transmit/receive for one i/o command.  This limitation is
381 	 * significant ony if it is less than (dlim_ctreg_max * dlim_sgllen).
382 	 */
383 	uint_t	dlim_reqsize;
384 
385 } ddi_dma_lim_t;
386 
387 #else
388 #error "struct ddi_dma_lim not defined for this architecture"
389 #endif	/* defined(__sparc) */
390 
391 /*
392  * Flags definition for dma_attr_flags
393  */
394 
395 /*
396  * return physical DMA address on platforms
397  * which support DVMA
398  */
399 #define	DDI_DMA_FORCE_PHYSICAL		0x0100
400 
401 /*
402  * An error will be flagged for DMA data path errors
403  */
404 #define	DDI_DMA_FLAGERR			0x200
405 
406 /*
407  * Enable relaxed ordering
408  */
409 #define	DDI_DMA_RELAXED_ORDERING	0x400
410 
411 
412 /*
413  * Consolidation private x86 only flag which will cause a bounce buffer
414  * (paddr < dma_attr_seg) to be used if the buffer passed to the bind
415  * operation contains pages both above and below dma_attr_seg. If this flag
416  * is set, dma_attr_seg must be <= dma_attr_addr_hi.
417  */
418 #define	_DDI_DMA_BOUNCE_ON_SEG		0x8000
419 
420 #define	DMA_ATTR_V0		0
421 #define	DMA_ATTR_VERSION	DMA_ATTR_V0
422 
423 typedef struct ddi_dma_attr {
424 	uint_t		dma_attr_version;	/* version number */
425 	uint64_t	dma_attr_addr_lo;	/* low DMA address range */
426 	uint64_t	dma_attr_addr_hi;	/* high DMA address range */
427 	uint64_t	dma_attr_count_max;	/* DMA counter register */
428 	uint64_t	dma_attr_align;		/* DMA address alignment */
429 	uint_t		dma_attr_burstsizes;	/* DMA burstsizes */
430 	uint32_t	dma_attr_minxfer;	/* min effective DMA size */
431 	uint64_t 	dma_attr_maxxfer;	/* max DMA xfer size */
432 	uint64_t 	dma_attr_seg;		/* segment boundary */
433 	int		dma_attr_sgllen;	/* s/g length */
434 	uint32_t	dma_attr_granular;	/* granularity of device */
435 	uint_t		dma_attr_flags;		/* Bus specific DMA flags */
436 } ddi_dma_attr_t;
437 
438 /*
439  * Handy macro to set a maximum bit value (should be elsewhere)
440  *
441  * Clear off all bits lower then 'mybit' in val; if there are no
442  * bits higher than or equal to mybit in val then set mybit. Assumes
443  * mybit equals some power of 2 and is not zero.
444  */
445 #define	maxbit(val, mybit)	\
446 	((val) & ~((mybit)-1)) | ((((val) & ~((mybit)-1)) == 0) ? (mybit) : 0)
447 
448 /*
449  * Handy macro to set a minimum bit value (should be elsewhere)
450  *
451  * Clear off all bits higher then 'mybit' in val; if there are no
452  * bits lower than or equal to mybit in val then set mybit. Assumes
453  * mybit equals some pow2 and is not zero.
454  */
455 #define	minbit(val, mybit)	\
456 	(((val)&((mybit)|((mybit)-1))) | \
457 	((((val) & ((mybit)-1)) == 0) ? (mybit) : 0))
458 
459 /*
460  * Structure of a request to map an object for DMA.
461  */
462 typedef struct ddi_dma_req {
463 	/*
464 	 * Caller's DMA engine constraints.
465 	 *
466 	 * If there are no particular constraints to the caller's DMA
467 	 * engine, this field may be set to NULL. The implementation DMA
468 	 * setup functions will then select a set of standard beginning
469 	 * constraints.
470 	 *
471 	 * In either case, as the mapping proceeds, the initial DMA
472 	 * constraints may become more restrictive as each intervening
473 	 * nexus might add further restrictions.
474 	 */
475 	ddi_dma_lim_t	*dmar_limits;
476 
477 	/*
478 	 * Contains the information passed to the DMA mapping allocation
479 	 * routine(s).
480 	 */
481 	uint_t		dmar_flags;
482 
483 	/*
484 	 * Callback function. A caller of the DMA mapping functions must
485 	 * specify by filling in this field whether the allocation routines
486 	 * can sleep awaiting mapping resources, must *not* sleep awaiting
487 	 * resources, or may *not* sleep awaiting any resources and must
488 	 * call the function specified by dmar_fp with the the argument
489 	 * dmar_arg when resources might have become available at a future
490 	 * time.
491 	 */
492 	int		(*dmar_fp)();
493 
494 	caddr_t		dmar_arg;	/* Callback function argument */
495 
496 	/*
497 	 * Description of the object to be mapped for DMA.
498 	 * Must be last in this structure in case that the
499 	 * union ddi_dma_obj_t changes in the future.
500 	 */
501 	ddi_dma_obj_t	dmar_object;
502 
503 } ddi_dma_req_t;
504 
505 /*
506  * Defines for the DMA mapping allocation functions
507  *
508  * If a DMA callback funtion is set to anything other than the following
509  * defines then it is assumed that one wishes a callback and is providing
510  * a function address.
511  */
512 #ifdef __STDC__
513 #define	DDI_DMA_DONTWAIT	((int (*)(caddr_t))0)
514 #define	DDI_DMA_SLEEP		((int (*)(caddr_t))1)
515 #else
516 #define	DDI_DMA_DONTWAIT	((int (*)())0)
517 #define	DDI_DMA_SLEEP		((int (*)())1)
518 #endif
519 
520 /*
521  * Return values from callback functions.
522  */
523 #define	DDI_DMA_CALLBACK_RUNOUT	0
524 #define	DDI_DMA_CALLBACK_DONE	1
525 
526 /*
527  * Flag definitions for the allocation functions.
528  */
529 #define	DDI_DMA_WRITE		0x0001	/* Direction memory --> IO 	*/
530 #define	DDI_DMA_READ		0x0002	/* Direction IO --> memory	*/
531 #define	DDI_DMA_RDWR		(DDI_DMA_READ | DDI_DMA_WRITE)
532 
533 /*
534  * If possible, establish a MMU redzone after the mapping (to protect
535  * against cheap DMA hardware that might get out of control).
536  */
537 #define	DDI_DMA_REDZONE		0x0004
538 
539 /*
540  * A partial allocation is allowed. That is, if the size of the object
541  * exceeds the mapping resources available, only map a portion of the
542  * object and return status indicating that this took place. The caller
543  * can use the functions ddi_dma_numwin(9F) and ddi_dma_getwin(9F) to
544  * change, at a later point, the actual mapped portion of the object.
545  *
546  * The mapped portion begins at offset 0 of the object.
547  *
548  */
549 #define	DDI_DMA_PARTIAL		0x0008
550 
551 /*
552  * Map the object for byte consistent access. Note that explicit
553  * synchronization (via ddi_dma_sync(9F)) will still be required.
554  * Consider this flag to be a hint to the mapping routines as to
555  * the intended use of the mapping.
556  *
557  * Normal data transfers can be usually consider to use 'streaming'
558  * modes of operations. They start at a specific point, transfer a
559  * fairly large amount of data sequentially, and then stop (usually
560  * on a well aligned boundary).
561  *
562  * Control mode data transfers (for memory resident device control blocks,
563  * e.g., ethernet message descriptors) do not access memory in such
564  * a streaming sequential fashion. Instead, they tend to modify a few
565  * words or bytes, move around and maybe modify a few more.
566  *
567  * There are many machine implementations that make this difficult to
568  * control in a generic and seamless fashion. Therefore, explicit synch-
569  * ronization steps (via ddi_dma_sync(9F)) are still required (even if you
570  * ask for a byte-consistent mapping) in order to make the view of the
571  * memory object shared between a CPU and a DMA master in consistent.
572  * However, judicious use of this flag can give sufficient hints to
573  * the mapping routines to attempt to pick the most efficacious mapping
574  * such that the synchronization steps are as efficient as possible.
575  *
576  */
577 #define	DDI_DMA_CONSISTENT	0x0010
578 
579 /*
580  * Some DMA mappings have to be 'exclusive' access.
581  */
582 #define	DDI_DMA_EXCLUSIVE	0x0020
583 
584 /*
585  * Sequential, unidirectional, block-sized and block aligned transfers
586  */
587 #define	DDI_DMA_STREAMING	0x0040
588 
589 /*
590  * Support for 64-bit SBus devices
591  */
592 #define	DDI_DMA_SBUS_64BIT	0x2000
593 
594 /*
595  * Return values from the mapping allocation functions.
596  */
597 
598 /*
599  * succeeded in satisfying request
600  */
601 #define	DDI_DMA_MAPPED		0
602 
603 /*
604  * Mapping is legitimate (for advisory calls).
605  */
606 #define	DDI_DMA_MAPOK		0
607 
608 /*
609  * Succeeded in mapping a portion of the request.
610  */
611 #define	DDI_DMA_PARTIAL_MAP	1
612 
613 /*
614  * indicates end of window/segment list
615  */
616 #define	DDI_DMA_DONE		2
617 
618 /*
619  * No resources to map request.
620  */
621 #define	DDI_DMA_NORESOURCES	-1
622 
623 /*
624  * Can't establish a mapping to the specified object
625  * (no specific reason).
626  */
627 #define	DDI_DMA_NOMAPPING	-2
628 
629 /*
630  * The request is too big to be mapped.
631  */
632 #define	DDI_DMA_TOOBIG		-3
633 
634 /*
635  * The request is too small to be mapped.
636  */
637 #define	DDI_DMA_TOOSMALL	-4
638 
639 /*
640  * The request cannot be mapped because the object
641  * is locked against mapping by another DMA master.
642  */
643 #define	DDI_DMA_LOCKED		-5
644 
645 /*
646  * The request cannot be mapped because the limits
647  * structure has bogus values.
648  */
649 #define	DDI_DMA_BADLIMITS	-6
650 
651 /*
652  * the segment/window pointer is stale
653  */
654 #define	DDI_DMA_STALE		-7
655 
656 /*
657  * The system can't allocate DMA resources using
658  * the given DMA attributes
659  */
660 #define	DDI_DMA_BADATTR		-8
661 
662 /*
663  * A DMA handle is already used for a DMA
664  */
665 #define	DDI_DMA_INUSE		-9
666 
667 
668 /*
669  * DVMA disabled or not supported. use physical DMA
670  */
671 #define	DDI_DMA_USE_PHYSICAL		-10
672 
673 
674 /*
675  * In order for the access to a memory object to be consistent
676  * between a device and a CPU, the function ddi_dma_sync(9F)
677  * must be called upon the DMA handle. The following flags
678  * define whose view of the object should be made consistent.
679  * There are different flags here because on different machines
680  * there are definite performance implications of how long
681  * such synchronization takes.
682  *
683  * DDI_DMA_SYNC_FORDEV makes all device references to the object
684  * mapped by the DMA handle up to date. It should be used by a
685  * driver after a cpu modifies the memory object (over the range
686  * specified by the other arguments to the ddi_dma_sync(9F) call).
687  *
688  * DDI_DMA_SYNC_FORCPU makes all cpu references to the object
689  * mapped by the DMA handle up to date. It should be used
690  * by a driver after the receipt of data from the device to
691  * the memory object is done (over the range specified by
692  * the other arguments to the ddi_dma_sync(9F) call).
693  *
694  * If the only mapping that concerns the driver is one for the
695  * kernel (such as memory allocated by ddi_iopb_alloc(9F)), the
696  * flag DDI_DMA_SYNC_FORKERNEL can be used. This is a hint to the
697  * system that if it can synchronize the kernel's view faster
698  * that the CPU's view, it can do so, otherwise it acts the
699  * same as DDI_DMA_SYNC_FORCPU. DDI_DMA_SYNC_FORKERNEL might
700  * speed up the synchronization of kernel mappings in case of
701  * non IO-coherent CPU caches.
702  */
703 #define	DDI_DMA_SYNC_FORDEV	0x0
704 #define	DDI_DMA_SYNC_FORCPU	0x1
705 #define	DDI_DMA_SYNC_FORKERNEL	0x2
706 
707 /*
708  * Bus nexus control functions for DMA
709  */
710 
711 /*
712  * Control operations, defined here so that devops.h can be included
713  * by drivers without having to include a specific SYSDDI implementation
714  * header file.
715  */
716 
717 enum ddi_dma_ctlops {
718 	DDI_DMA_FREE,		/* obsolete - do not use		*/
719 	DDI_DMA_SYNC,		/* obsolete - do not use		*/
720 	DDI_DMA_HTOC,		/* obsolete - do not use		*/
721 	DDI_DMA_KVADDR,		/* obsolete - do not use		*/
722 	DDI_DMA_MOVWIN,		/* obsolete - do not use		*/
723 	DDI_DMA_REPWIN,		/* obsolete - do not use		*/
724 	DDI_DMA_GETERR,		/* obsolete - do not use		*/
725 	DDI_DMA_COFF,		/* obsolete - do not use		*/
726 	DDI_DMA_NEXTWIN,	/* obsolete - do not use		*/
727 	DDI_DMA_NEXTSEG,	/* obsolete - do not use		*/
728 	DDI_DMA_SEGTOC,		/* obsolete - do not use		*/
729 	DDI_DMA_RESERVE,	/* reserve some DVMA range		*/
730 	DDI_DMA_RELEASE,	/* free preallocated DVMA range		*/
731 	DDI_DMA_RESETH,		/* obsolete - do not use		*/
732 	DDI_DMA_CKSYNC,		/* obsolete - do not use		*/
733 	DDI_DMA_IOPB_ALLOC,	/* get contiguous DMA-able memory	*/
734 	DDI_DMA_IOPB_FREE,	/* return contiguous DMA-able memory	*/
735 	DDI_DMA_SMEM_ALLOC,	/* get contiguous DMA-able memory	*/
736 	DDI_DMA_SMEM_FREE,	/* return contiguous DMA-able memory	*/
737 	DDI_DMA_SET_SBUS64,	/* 64 bit SBus support			*/
738 	DDI_DMA_REMAP,		/* remap DMA buffers after relocation	*/
739 
740 		/*
741 		 * control ops for DMA engine on motherboard
742 		 */
743 	DDI_DMA_E_ACQUIRE,	/* get channel for exclusive use	*/
744 	DDI_DMA_E_FREE,		/* release channel			*/
745 	DDI_DMA_E_1STPTY,	/* setup channel for 1st party DMA	*/
746 	DDI_DMA_E_GETCB,	/* get control block for DMA engine	*/
747 	DDI_DMA_E_FREECB,	/* free control blk for DMA engine	*/
748 	DDI_DMA_E_PROG,		/* program channel of DMA engine	*/
749 	DDI_DMA_E_SWSETUP,	/* setup channel for software control	*/
750 	DDI_DMA_E_SWSTART,	/* software operation of DMA channel	*/
751 	DDI_DMA_E_ENABLE,	/* enable channel of DMA engine		*/
752 	DDI_DMA_E_STOP,		/* stop a channel of DMA engine		*/
753 	DDI_DMA_E_DISABLE,	/* disable channel of DMA engine	*/
754 	DDI_DMA_E_GETCNT,	/* get remaining xfer count		*/
755 	DDI_DMA_E_GETLIM,	/* get DMA engine limits		*/
756 	DDI_DMA_E_GETATTR	/* get DMA engine attributes		*/
757 };
758 
759 /*
760  * Cache attribute flags:
761  *
762  * IOMEM_DATA_CACHED
763  *   The CPU can cache the data it fetches and push it to memory at a later
764  *   time. This is the default attribute and used if no cache attributes is
765  *   specified.
766  *
767  * IOMEM_DATA_UC_WR_COMBINE
768  *   The CPU never caches the data but writes may occur out of order or be
769  *   combined. It implies re-ordering.
770  *
771  * IOMEM_DATA_UNCACHED
772  *   The CPU never caches the data and has uncacheable access to memory.
773  *   It also implies strict ordering.
774  *
775  * The cache attributes are mutually exclusive, and any combination of the
776  * values leads to a failure. On the sparc architecture, only IOMEM_DATA_CACHED
777  * is meaningful, but others lead to a failure.
778  */
779 #define	IOMEM_DATA_CACHED		0x10000 /* data is cached */
780 #define	IOMEM_DATA_UC_WR_COMBINE	0x20000 /* data is not cached, but */
781 						/* writes might be combined */
782 #define	IOMEM_DATA_UNCACHED		0x40000 /* data is not cached. */
783 #define	IOMEM_DATA_MASK			0xF0000	/* cache attrs mask */
784 
785 /*
786  * Check if either uncacheable or write-combining specified. (those flags are
787  * mutually exclusive) This macro is used to override hat attributes if either
788  * one is set.
789  */
790 #define	OVERRIDE_CACHE_ATTR(attr)	\
791 	(attr & (IOMEM_DATA_UNCACHED | IOMEM_DATA_UC_WR_COMBINE))
792 
793 /*
794  * Get the cache attribute from flags. If there is no attributes,
795  * return IOMEM_DATA_CACHED (default attribute).
796  */
797 #define	IOMEM_CACHE_ATTR(flags)	\
798 	((flags & IOMEM_DATA_MASK) ? (flags & IOMEM_DATA_MASK) : \
799 	    IOMEM_DATA_CACHED)
800 
801 #ifdef	__cplusplus
802 }
803 #endif
804 
805 #endif	/* _SYS_DDIDMAREQ_H */
806