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      1 /*	$NetBSD: bus_defs.h,v 1.19 2022/10/15 11:07:38 jmcneill Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996, 1997, 1998, 2001 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9  * NASA Ames Research Center.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30  * POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 /*
     34  * Copyright (c) 1996 Charles M. Hannum.  All rights reserved.
     35  * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
     36  *
     37  * Redistribution and use in source and binary forms, with or without
     38  * modification, are permitted provided that the following conditions
     39  * are met:
     40  * 1. Redistributions of source code must retain the above copyright
     41  *    notice, this list of conditions and the following disclaimer.
     42  * 2. Redistributions in binary form must reproduce the above copyright
     43  *    notice, this list of conditions and the following disclaimer in the
     44  *    documentation and/or other materials provided with the distribution.
     45  * 3. All advertising materials mentioning features or use of this software
     46  *    must display the following acknowledgement:
     47  *      This product includes software developed by Christopher G. Demetriou
     48  *	for the NetBSD Project.
     49  * 4. The name of the author may not be used to endorse or promote products
     50  *    derived from this software without specific prior written permission
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     53  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     54  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     55  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     56  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     57  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     58  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     59  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     60  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     61  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     62  */
     63 
     64 #ifndef _ARM_BUS_DEFS_H_
     65 #define _ARM_BUS_DEFS_H_
     66 
     67 #if defined(_KERNEL_OPT)
     68 #include "opt_arm_bus_space.h"
     69 #include "opt_kasan.h"
     70 #endif
     71 
     72 /*
     73  * Addresses (in bus space).
     74  */
     75 typedef u_long bus_addr_t;
     76 typedef u_long bus_size_t;
     77 
     78 #define	PRIxBUSADDR	"lx"
     79 #define	PRIxBUSSIZE	"lx"
     80 #define	PRIuBUSSIZE	"lu"
     81 
     82 /*
     83  * Access methods for bus space.
     84  */
     85 typedef struct bus_space *bus_space_tag_t;
     86 typedef u_long bus_space_handle_t;
     87 
     88 #define	PRIxBSH		"lx"
     89 
     90 /*
     91  *	int bus_space_map(bus_space_tag_t t, bus_addr_t addr,
     92  *	    bus_size_t size, int flags, bus_space_handle_t *bshp);
     93  *
     94  * Map a region of bus space.
     95  */
     96 
     97 #define	BUS_SPACE_MAP_CACHEABLE		0x01
     98 #define	BUS_SPACE_MAP_LINEAR		0x02
     99 #define	BUS_SPACE_MAP_PREFETCHABLE     	0x04
    100 
    101 #define	BUS_SPACE_MAP_BUS1		0x0100
    102 #define	BUS_SPACE_MAP_BUS2		0x0200
    103 #define	BUS_SPACE_MAP_BUS3		0x0400
    104 #define	BUS_SPACE_MAP_BUS4		0x0800
    105 
    106 #define	BUS_SPACE_MAP_NONPOSTED		BUS_SPACE_MAP_BUS1
    107 
    108 struct bus_space {
    109 	/* cookie */
    110 	void		*bs_cookie;
    111 
    112 	/* used for aarch64. require ".bs_cookie = bus_space" */
    113 	int		bs_stride;	/* offset <<= bs_stride (if needed) */
    114 	int		bs_flags;
    115 
    116 	/* mapping/unmapping */
    117 	int		(*bs_map)(void *, bus_addr_t, bus_size_t,
    118 			    int, bus_space_handle_t *);
    119 	void		(*bs_unmap)(void *, bus_space_handle_t,
    120 			    bus_size_t);
    121 	int		(*bs_subregion)(void *, bus_space_handle_t,
    122 			    bus_size_t, bus_size_t, bus_space_handle_t *);
    123 
    124 	/* allocation/deallocation */
    125 	int		(*bs_alloc)(void *, bus_addr_t, bus_addr_t,
    126 			    bus_size_t, bus_size_t, bus_size_t, int,
    127 			    bus_addr_t *, bus_space_handle_t *);
    128 	void		(*bs_free)(void *, bus_space_handle_t,
    129 			    bus_size_t);
    130 
    131 	/* get kernel virtual address */
    132 	void *		(*bs_vaddr)(void *, bus_space_handle_t);
    133 
    134 	/* mmap bus space for user */
    135 	paddr_t		(*bs_mmap)(void *, bus_addr_t, off_t, int, int);
    136 
    137 	/* barrier */
    138 	void		(*bs_barrier)(void *, bus_space_handle_t,
    139 			    bus_size_t, bus_size_t, int);
    140 
    141 	/* read (single) */
    142 	uint8_t		(*bs_r_1)(void *, bus_space_handle_t,
    143 			    bus_size_t);
    144 	uint16_t	(*bs_r_2)(void *, bus_space_handle_t,
    145 			    bus_size_t);
    146 	uint32_t	(*bs_r_4)(void *, bus_space_handle_t,
    147 			    bus_size_t);
    148 	uint64_t	(*bs_r_8)(void *, bus_space_handle_t,
    149 			    bus_size_t);
    150 
    151 	/* read multiple */
    152 	void		(*bs_rm_1)(void *, bus_space_handle_t,
    153 			    bus_size_t, uint8_t *, bus_size_t);
    154 	void		(*bs_rm_2)(void *, bus_space_handle_t,
    155 			    bus_size_t, uint16_t *, bus_size_t);
    156 	void		(*bs_rm_4)(void *, bus_space_handle_t,
    157 			    bus_size_t, uint32_t *, bus_size_t);
    158 	void		(*bs_rm_8)(void *, bus_space_handle_t,
    159 			    bus_size_t, uint64_t *, bus_size_t);
    160 
    161 	/* read region */
    162 	void		(*bs_rr_1)(void *, bus_space_handle_t,
    163 			    bus_size_t, uint8_t *, bus_size_t);
    164 	void		(*bs_rr_2)(void *, bus_space_handle_t,
    165 			    bus_size_t, uint16_t *, bus_size_t);
    166 	void		(*bs_rr_4)(void *, bus_space_handle_t,
    167 			    bus_size_t, uint32_t *, bus_size_t);
    168 	void		(*bs_rr_8)(void *, bus_space_handle_t,
    169 			    bus_size_t, uint64_t *, bus_size_t);
    170 
    171 	/* write (single) */
    172 	void		(*bs_w_1)(void *, bus_space_handle_t,
    173 			    bus_size_t, uint8_t);
    174 	void		(*bs_w_2)(void *, bus_space_handle_t,
    175 			    bus_size_t, uint16_t);
    176 	void		(*bs_w_4)(void *, bus_space_handle_t,
    177 			    bus_size_t, uint32_t);
    178 	void		(*bs_w_8)(void *, bus_space_handle_t,
    179 			    bus_size_t, uint64_t);
    180 
    181 	/* write multiple */
    182 	void		(*bs_wm_1)(void *, bus_space_handle_t,
    183 			    bus_size_t, const uint8_t *, bus_size_t);
    184 	void		(*bs_wm_2)(void *, bus_space_handle_t,
    185 			    bus_size_t, const uint16_t *, bus_size_t);
    186 	void		(*bs_wm_4)(void *, bus_space_handle_t,
    187 			    bus_size_t, const uint32_t *, bus_size_t);
    188 	void		(*bs_wm_8)(void *, bus_space_handle_t,
    189 			    bus_size_t, const uint64_t *, bus_size_t);
    190 
    191 	/* write region */
    192 	void		(*bs_wr_1)(void *, bus_space_handle_t,
    193 			    bus_size_t, const uint8_t *, bus_size_t);
    194 	void		(*bs_wr_2)(void *, bus_space_handle_t,
    195 			    bus_size_t, const uint16_t *, bus_size_t);
    196 	void		(*bs_wr_4)(void *, bus_space_handle_t,
    197 			    bus_size_t, const uint32_t *, bus_size_t);
    198 	void		(*bs_wr_8)(void *, bus_space_handle_t,
    199 			    bus_size_t, const uint64_t *, bus_size_t);
    200 
    201 	/* set multiple */
    202 	void		(*bs_sm_1)(void *, bus_space_handle_t,
    203 			    bus_size_t, uint8_t, bus_size_t);
    204 	void		(*bs_sm_2)(void *, bus_space_handle_t,
    205 			    bus_size_t, uint16_t, bus_size_t);
    206 	void		(*bs_sm_4)(void *, bus_space_handle_t,
    207 			    bus_size_t, uint32_t, bus_size_t);
    208 	void		(*bs_sm_8)(void *, bus_space_handle_t,
    209 			    bus_size_t, uint64_t, bus_size_t);
    210 
    211 	/* set region */
    212 	void		(*bs_sr_1)(void *, bus_space_handle_t,
    213 			    bus_size_t, uint8_t, bus_size_t);
    214 	void		(*bs_sr_2)(void *, bus_space_handle_t,
    215 			    bus_size_t, uint16_t, bus_size_t);
    216 	void		(*bs_sr_4)(void *, bus_space_handle_t,
    217 			    bus_size_t, uint32_t, bus_size_t);
    218 	void		(*bs_sr_8)(void *, bus_space_handle_t,
    219 			    bus_size_t, uint64_t, bus_size_t);
    220 
    221 	/* copy */
    222 	void		(*bs_c_1)(void *, bus_space_handle_t, bus_size_t,
    223 			    bus_space_handle_t, bus_size_t, bus_size_t);
    224 	void		(*bs_c_2)(void *, bus_space_handle_t, bus_size_t,
    225 			    bus_space_handle_t, bus_size_t, bus_size_t);
    226 	void		(*bs_c_4)(void *, bus_space_handle_t, bus_size_t,
    227 			    bus_space_handle_t, bus_size_t, bus_size_t);
    228 	void		(*bs_c_8)(void *, bus_space_handle_t, bus_size_t,
    229 			    bus_space_handle_t, bus_size_t, bus_size_t);
    230 
    231 #ifdef __BUS_SPACE_HAS_STREAM_METHODS
    232 	/* read stream (single) */
    233 	uint8_t		(*bs_r_1_s)(void *, bus_space_handle_t,
    234 			    bus_size_t);
    235 	uint16_t	(*bs_r_2_s)(void *, bus_space_handle_t,
    236 			    bus_size_t);
    237 	uint32_t	(*bs_r_4_s)(void *, bus_space_handle_t,
    238 			    bus_size_t);
    239 	uint64_t	(*bs_r_8_s)(void *, bus_space_handle_t,
    240 			    bus_size_t);
    241 
    242 	/* read multiple stream */
    243 	void		(*bs_rm_1_s)(void *, bus_space_handle_t,
    244 			    bus_size_t, uint8_t *, bus_size_t);
    245 	void		(*bs_rm_2_s)(void *, bus_space_handle_t,
    246 			    bus_size_t, uint16_t *, bus_size_t);
    247 	void		(*bs_rm_4_s)(void *, bus_space_handle_t,
    248 			    bus_size_t, uint32_t *, bus_size_t);
    249 	void		(*bs_rm_8_s)(void *, bus_space_handle_t,
    250 			    bus_size_t, uint64_t *, bus_size_t);
    251 
    252 	/* read region stream */
    253 	void		(*bs_rr_1_s)(void *, bus_space_handle_t,
    254 			    bus_size_t, uint8_t *, bus_size_t);
    255 	void		(*bs_rr_2_s)(void *, bus_space_handle_t,
    256 			    bus_size_t, uint16_t *, bus_size_t);
    257 	void		(*bs_rr_4_s)(void *, bus_space_handle_t,
    258 			    bus_size_t, uint32_t *, bus_size_t);
    259 	void		(*bs_rr_8_s)(void *, bus_space_handle_t,
    260 			    bus_size_t, uint64_t *, bus_size_t);
    261 
    262 	/* write stream (single) */
    263 	void		(*bs_w_1_s)(void *, bus_space_handle_t,
    264 			    bus_size_t, uint8_t);
    265 	void		(*bs_w_2_s)(void *, bus_space_handle_t,
    266 			    bus_size_t, uint16_t);
    267 	void		(*bs_w_4_s)(void *, bus_space_handle_t,
    268 			    bus_size_t, uint32_t);
    269 	void		(*bs_w_8_s)(void *, bus_space_handle_t,
    270 			    bus_size_t, uint64_t);
    271 
    272 	/* write multiple stream */
    273 	void		(*bs_wm_1_s)(void *, bus_space_handle_t,
    274 			    bus_size_t, const uint8_t *, bus_size_t);
    275 	void		(*bs_wm_2_s)(void *, bus_space_handle_t,
    276 			    bus_size_t, const uint16_t *, bus_size_t);
    277 	void		(*bs_wm_4_s)(void *, bus_space_handle_t,
    278 			    bus_size_t, const uint32_t *, bus_size_t);
    279 	void		(*bs_wm_8_s)(void *, bus_space_handle_t,
    280 			    bus_size_t, const uint64_t *, bus_size_t);
    281 
    282 	/* write region stream */
    283 	void		(*bs_wr_1_s)(void *, bus_space_handle_t,
    284 			    bus_size_t, const uint8_t *, bus_size_t);
    285 	void		(*bs_wr_2_s)(void *, bus_space_handle_t,
    286 			    bus_size_t, const uint16_t *, bus_size_t);
    287 	void		(*bs_wr_4_s)(void *, bus_space_handle_t,
    288 			    bus_size_t, const uint32_t *, bus_size_t);
    289 	void		(*bs_wr_8_s)(void *, bus_space_handle_t,
    290 			    bus_size_t, const uint64_t *, bus_size_t);
    291 #endif	/* __BUS_SPACE_HAS_STREAM_METHODS */
    292 
    293 #ifdef __BUS_SPACE_HAS_PROBING_METHODS
    294 	/* peek */
    295 	int		(*bs_pe_1)(void *, bus_space_handle_t,
    296 			    bus_size_t, uint8_t *);
    297 	int		(*bs_pe_2)(void *, bus_space_handle_t,
    298 			    bus_size_t, uint16_t *);
    299 	int		(*bs_pe_4)(void *, bus_space_handle_t,
    300 			    bus_size_t, uint32_t *);
    301 	int		(*bs_pe_8)(void *, bus_space_handle_t,
    302 			    bus_size_t, uint64_t *);
    303 
    304 	/* poke */
    305 	int		(*bs_po_1)(void *, bus_space_handle_t,
    306 			    bus_size_t, uint8_t);
    307 	int		(*bs_po_2)(void *, bus_space_handle_t,
    308 			    bus_size_t, uint16_t);
    309 	int		(*bs_po_4)(void *, bus_space_handle_t,
    310 			    bus_size_t, uint32_t);
    311 	int		(*bs_po_8)(void *, bus_space_handle_t,
    312 			    bus_size_t, uint64_t);
    313 #endif /* __BUS_SPACE_HAS_PROBING_METHODS */
    314 };
    315 
    316 #define	BUS_SPACE_BARRIER_READ	0x01
    317 #define	BUS_SPACE_BARRIER_WRITE	0x02
    318 
    319 #define BUS_SPACE_ALIGNED_POINTER(p, t) ALIGNED_POINTER(p, t)
    320 
    321 /* Bus Space DMA macros */
    322 
    323 /*
    324  * Flags used in various bus DMA methods.
    325  */
    326 #define	BUS_DMA_WAITOK		0x000	/* safe to sleep (pseudo-flag) */
    327 #define	BUS_DMA_NOWAIT		0x001	/* not safe to sleep */
    328 #define	BUS_DMA_ALLOCNOW	0x002	/* perform resource allocation now */
    329 #define	BUS_DMA_COHERENT	0x004	/* hint: map memory DMA coherent */
    330 #define	BUS_DMA_STREAMING	0x008	/* hint: sequential, unidirectional */
    331 #define	BUS_DMA_BUS1		0x010	/* placeholders for bus functions... */
    332 #define	BUS_DMA_BUS2		0x020
    333 #define	BUS_DMA_BUS3		0x040
    334 #define	BUS_DMA_BUS4		0x080
    335 #define	BUS_DMA_READ		0x100	/* mapping is device -> memory only */
    336 #define	BUS_DMA_WRITE		0x200	/* mapping is memory -> device only */
    337 #define	BUS_DMA_NOCACHE		0x400	/* hint: map non-cached memory */
    338 
    339 /*
    340  * Private flags stored in the DMA map.
    341  */
    342 #define	_BUS_DMAMAP_COHERENT	0x10000	/* no cache flush necessary on sync */
    343 #define	_BUS_DMAMAP_IS_BOUNCING	0x20000 /* is bouncing current xfer */
    344 #define	_BUS_DMAMAP_NOALLOC	0x40000	/* don't alloc memory from this range */
    345 
    346 /* Forwards needed by prototypes below. */
    347 struct mbuf;
    348 struct uio;
    349 
    350 /*
    351  * Operations performed by bus_dmamap_sync().
    352  */
    353 #define	BUS_DMASYNC_PREREAD	0x01	/* pre-read synchronization */
    354 #define	BUS_DMASYNC_POSTREAD	0x02	/* post-read synchronization */
    355 #define	BUS_DMASYNC_PREWRITE	0x04	/* pre-write synchronization */
    356 #define	BUS_DMASYNC_POSTWRITE	0x08	/* post-write synchronization */
    357 
    358 typedef struct arm32_bus_dma_tag	*bus_dma_tag_t;
    359 typedef struct arm32_bus_dmamap		*bus_dmamap_t;
    360 
    361 #define BUS_DMA_TAG_VALID(t)    ((t) != (bus_dma_tag_t)0)
    362 
    363 /*
    364  *	bus_dma_segment_t
    365  *
    366  *	Describes a single contiguous DMA transaction.  Values
    367  *	are suitable for programming into DMA registers.
    368  */
    369 struct arm32_bus_dma_segment {
    370 	/*
    371 	 * PUBLIC MEMBERS: these are used by machine-independent code.
    372 	 */
    373 	bus_addr_t	ds_addr;	/* DMA address */
    374 	bus_size_t	ds_len;		/* length of transfer */
    375 
    376 	/*
    377 	 * PRIVATE MEMBERS:
    378 	 */
    379 	uint32_t	_ds_flags;	/* _BUS_DMAMAP_COHERENT */
    380 	paddr_t		_ds_paddr;	/* CPU address */
    381 };
    382 typedef struct arm32_bus_dma_segment	bus_dma_segment_t;
    383 
    384 /*
    385  *	arm32_dma_range
    386  *
    387  *	This structure describes a valid DMA range.
    388  */
    389 struct arm32_dma_range {
    390 	bus_addr_t	dr_sysbase;	/* system base address */
    391 	bus_addr_t	dr_busbase;	/* appears here on bus */
    392 	bus_size_t	dr_len;		/* length of range */
    393 	uint32_t	dr_flags;	/* flags for range */
    394 };
    395 
    396 /*
    397  *	bus_dma_tag_t
    398  *
    399  *	A machine-dependent opaque type describing the implementation of
    400  *	DMA for a given bus.
    401  */
    402 
    403 struct arm32_bus_dma_tag {
    404 	/*
    405 	 * DMA range for this tag.  If the page doesn't fall within
    406 	 * one of these ranges, an error is returned.  The caller
    407 	 * may then decide what to do with the transfer.  If the
    408 	 * range pointer is NULL, it is ignored.
    409 	 */
    410 	struct arm32_dma_range *_ranges;
    411 	int _nranges;
    412 
    413 	/*
    414 	 * Opaque cookie for use by back-end.
    415 	 */
    416 	void *_cookie;
    417 
    418 	/*
    419 	 * DMA mapping methods.
    420 	 */
    421 	int	(*_dmamap_create)(bus_dma_tag_t, bus_size_t, int,
    422 		    bus_size_t, bus_size_t, int, bus_dmamap_t *);
    423 	void	(*_dmamap_destroy)(bus_dma_tag_t, bus_dmamap_t);
    424 	int	(*_dmamap_load)(bus_dma_tag_t, bus_dmamap_t, void *,
    425 		    bus_size_t, struct proc *, int);
    426 	int	(*_dmamap_load_mbuf)(bus_dma_tag_t, bus_dmamap_t,
    427 		    struct mbuf *, int);
    428 	int	(*_dmamap_load_uio)(bus_dma_tag_t, bus_dmamap_t,
    429 		    struct uio *, int);
    430 	int	(*_dmamap_load_raw)(bus_dma_tag_t, bus_dmamap_t,
    431 		    bus_dma_segment_t *, int, bus_size_t, int);
    432 	void	(*_dmamap_unload)(bus_dma_tag_t, bus_dmamap_t);
    433 	void	(*_dmamap_sync_pre)(bus_dma_tag_t, bus_dmamap_t,
    434 		    bus_addr_t, bus_size_t, int);
    435 	void	(*_dmamap_sync_post)(bus_dma_tag_t, bus_dmamap_t,
    436 		    bus_addr_t, bus_size_t, int);
    437 
    438 	/*
    439 	 * DMA memory utility functions.
    440 	 */
    441 	int	(*_dmamem_alloc)(bus_dma_tag_t, bus_size_t, bus_size_t,
    442 		    bus_size_t, bus_dma_segment_t *, int, int *, int);
    443 	void	(*_dmamem_free)(bus_dma_tag_t,
    444 		    bus_dma_segment_t *, int);
    445 	int	(*_dmamem_map)(bus_dma_tag_t, bus_dma_segment_t *,
    446 		    int, size_t, void **, int);
    447 	void	(*_dmamem_unmap)(bus_dma_tag_t, void *, size_t);
    448 	paddr_t	(*_dmamem_mmap)(bus_dma_tag_t, bus_dma_segment_t *,
    449 		    int, off_t, int, int);
    450 
    451 	/*
    452 	 * DMA tag utility functions
    453 	 */
    454 	int	(*_dmatag_subregion)(bus_dma_tag_t, bus_addr_t, bus_addr_t,
    455 		     bus_dma_tag_t *, int);
    456 	void	(*_dmatag_destroy)(bus_dma_tag_t);
    457 
    458 	/*
    459 	 * State for bounce buffers
    460 	 */
    461 	int	_tag_needs_free;
    462 	int	(*_may_bounce)(bus_dma_tag_t, bus_dmamap_t, int, int *);
    463 };
    464 
    465 /*
    466  *	bus_dmamap_t
    467  *
    468  *	Describes a DMA mapping.
    469  */
    470 struct arm32_bus_dmamap {
    471 	/*
    472 	 * PRIVATE MEMBERS: not for use by machine-independent code.
    473 	 */
    474 	bus_size_t	_dm_size;	/* largest DMA transfer mappable */
    475 	int		_dm_segcnt;	/* number of segs this map can map */
    476 	bus_size_t	_dm_maxmaxsegsz; /* fixed largest possible segment */
    477 	bus_size_t	_dm_boundary;	/* don't cross this */
    478 	int		_dm_flags;	/* misc. flags */
    479 
    480 	void		*_dm_origbuf;	/* pointer to original buffer */
    481 	int		_dm_buftype;	/* type of buffer */
    482 	struct vmspace	*_dm_vmspace;	/* vmspace that owns the mapping */
    483 
    484 	void		*_dm_cookie;	/* cookie for bus-specific functions */
    485 	void		*_dm_iommu;	/* cookie for iommu functions */
    486 
    487 	/*
    488 	 * PUBLIC MEMBERS: these are used by machine-independent code.
    489 	 */
    490 #if defined(KASAN)
    491 	void		*dm_buf;
    492 	bus_size_t	dm_buflen;
    493 	int		dm_buftype;
    494 #endif
    495 	bus_size_t	dm_maxsegsz;	/* largest possible segment */
    496 	bus_size_t	dm_mapsize;	/* size of the mapping */
    497 	int		dm_nsegs;	/* # valid segments in mapping */
    498 	bus_dma_segment_t dm_segs[1];	/* segments; variable length */
    499 };
    500 
    501 /* _dm_buftype */
    502 #define	_BUS_DMA_BUFTYPE_INVALID	0
    503 #define	_BUS_DMA_BUFTYPE_LINEAR		1
    504 #define	_BUS_DMA_BUFTYPE_MBUF		2
    505 #define	_BUS_DMA_BUFTYPE_UIO		3
    506 #define	_BUS_DMA_BUFTYPE_RAW		4
    507 
    508 #ifdef _ARM32_BUS_DMA_PRIVATE
    509 #define	_BUS_AVAIL_END	(physical_end - 1)
    510 /*
    511  * Cookie used for bounce buffers. A pointer to one of these it stashed in
    512  * the DMA map.
    513  */
    514 struct arm32_bus_dma_cookie {
    515 	int	id_flags;		/* flags; see below */
    516 
    517 	/*
    518 	 * Information about the original buffer used during
    519 	 * DMA map syncs.  Note that origibuflen is only used
    520 	 * for ID_BUFTYPE_LINEAR.
    521 	 */
    522 	union {
    523 		void	*un_origbuf;		/* pointer to orig buffer if
    524 						   bouncing */
    525 		char	*un_linearbuf;
    526 		struct mbuf	*un_mbuf;
    527 		struct uio	*un_uio;
    528 	} id_origbuf_un;
    529 #define	id_origbuf		id_origbuf_un.un_origbuf
    530 #define	id_origlinearbuf	id_origbuf_un.un_linearbuf
    531 #define	id_origmbuf		id_origbuf_un.un_mbuf
    532 #define	id_origuio		id_origbuf_un.un_uio
    533 	bus_size_t id_origbuflen;	/* ...and size */
    534 
    535 	void	*id_bouncebuf;		/* pointer to the bounce buffer */
    536 	bus_size_t id_bouncebuflen;	/* ...and size */
    537 	int	id_nbouncesegs;		/* number of valid bounce segs */
    538 	bus_dma_segment_t id_bouncesegs[0]; /* array of bounce buffer
    539 					       physical memory segments */
    540 };
    541 
    542 /* id_flags */
    543 #define	_BUS_DMA_IS_BOUNCING		0x04	/* is bouncing current xfer */
    544 #define	_BUS_DMA_HAS_BOUNCE		0x02	/* has bounce buffers */
    545 #endif /* _ARM32_BUS_DMA_PRIVATE */
    546 #define	_BUS_DMA_MIGHT_NEED_BOUNCE	0x01	/* may need bounce buffers */
    547 
    548 #endif /* _ARM_BUS_DEFS_H_ */
    549