xref: /freebsd/sys/dev/ioat/ioat.h (revision 290bb03c0ccd7309f502cdfbc50866e3d9461638)
1 /*-
2  * Copyright (C) 2012 Intel Corporation
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 __FBSDID("$FreeBSD$");
28 
29 #ifndef __IOAT_H__
30 #define __IOAT_H__
31 
32 #include <sys/param.h>
33 #include <machine/bus.h>
34 
35 /*
36  * This file defines the public interface to the IOAT driver.
37  */
38 
39 /*
40  * Enables an interrupt for this operation. Typically, you would only enable
41  * this on the last operation in a group
42  */
43 #define	DMA_INT_EN	0x1
44 /*
45  * Like M_NOWAIT.  Operations will return NULL if they cannot allocate a
46  * descriptor without blocking.
47  */
48 #define	DMA_NO_WAIT	0x2
49 #define	DMA_ALL_FLAGS	(DMA_INT_EN | DMA_NO_WAIT)
50 
51 typedef void *bus_dmaengine_t;
52 struct bus_dmadesc;
53 typedef void (*bus_dmaengine_callback_t)(void *arg, int error);
54 
55 /*
56  * Called first to acquire a reference to the DMA channel
57  */
58 bus_dmaengine_t ioat_get_dmaengine(uint32_t channel_index);
59 
60 /* Release the DMA channel */
61 void ioat_put_dmaengine(bus_dmaengine_t dmaengine);
62 
63 /*
64  * Set interrupt coalescing on a DMA channel.
65  *
66  * The argument is in microseconds.  A zero value disables coalescing.  Any
67  * other value delays interrupt generation for N microseconds to provide
68  * opportunity to coalesce multiple operations into a single interrupt.
69  *
70  * Returns an error status, or zero on success.
71  *
72  * - ERANGE if the given value exceeds the delay supported by the hardware.
73  *   (All current hardware supports a maximum of 0x3fff microseconds delay.)
74  * - ENODEV if the hardware does not support interrupt coalescing.
75  */
76 int ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay);
77 
78 /*
79  * Return the maximum supported coalescing period, for use in
80  * ioat_set_interrupt_coalesce().  If the hardware does not support coalescing,
81  * returns zero.
82  */
83 uint16_t ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine);
84 
85 /*
86  * Acquire must be called before issuing an operation to perform. Release is
87  * called after. Multiple operations can be issued within the context of one
88  * acquire and release
89  */
90 void ioat_acquire(bus_dmaengine_t dmaengine);
91 void ioat_release(bus_dmaengine_t dmaengine);
92 
93 /*
94  * Issue a blockfill operation.  The 64-bit pattern 'fillpattern' is written to
95  * 'len' physically contiguous bytes at 'dst'.
96  *
97  * Only supported on devices with the BFILL capability.
98  */
99 struct bus_dmadesc *ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst,
100     uint64_t fillpattern, bus_size_t len, bus_dmaengine_callback_t callback_fn,
101     void *callback_arg, uint32_t flags);
102 
103 /* Issues the copy data operation */
104 struct bus_dmadesc *ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
105     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
106     void *callback_arg, uint32_t flags);
107 
108 /*
109  * Issue a copy data operation, with constraints:
110  *  - src1, src2, dst1, dst2 are all page-aligned addresses
111  *  - The quantity to copy is exactly 2 pages;
112  *  - src1 -> dst1, src2 -> dst2
113  *
114  * Why use this instead of normal _copy()?  You can copy two non-contiguous
115  * pages (src, dst, or both) with one descriptor.
116  */
117 struct bus_dmadesc *ioat_copy_8k_aligned(bus_dmaengine_t dmaengine,
118     bus_addr_t dst1, bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
119     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
120 
121 /*
122  * Issues a null operation. This issues the operation to the hardware, but the
123  * hardware doesn't do anything with it.
124  */
125 struct bus_dmadesc *ioat_null(bus_dmaengine_t dmaengine,
126     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
127 
128 
129 #endif /* __IOAT_H__ */
130 
131