xref: /freebsd/sys/dev/ioat/ioat.h (revision b9c36cc755002809a7d7c7109e3425fdfca036d2)
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 /*
50  * Disallow prefetching the source of the following operation.  Ordinarily, DMA
51  * operations can be pipelined on some hardware.  E.g., operation 2's source
52  * may be prefetched before operation 1 completes.
53  */
54 #define	DMA_FENCE	0x4
55 #define	_DMA_GENERIC_FLAGS	(DMA_INT_EN | DMA_NO_WAIT | DMA_FENCE)
56 
57 /*
58  * Emit a CRC32C as the result of a ioat_copy_crc() or ioat_crc().
59  */
60 #define	DMA_CRC_STORE	0x8
61 
62 /*
63  * Compare the CRC32C of a ioat_copy_crc() or ioat_crc() against an expeceted
64  * value.  It is invalid to specify both TEST and STORE.
65  */
66 #define	DMA_CRC_TEST	0x10
67 #define	_DMA_CRC_TESTSTORE	(DMA_CRC_STORE | DMA_CRC_TEST)
68 
69 /*
70  * Use an inline comparison CRC32C or emit an inline CRC32C result.  Invalid
71  * without one of STORE or TEST.
72  */
73 #define	DMA_CRC_INLINE	0x20
74 #define	_DMA_CRC_FLAGS	(DMA_CRC_STORE | DMA_CRC_TEST | DMA_CRC_INLINE)
75 
76 /*
77  * Hardware revision number.  Different hardware revisions support different
78  * features.  For example, 3.2 cannot read from MMIO space, while 3.3 can.
79  */
80 #define	IOAT_VER_3_0			0x30
81 #define	IOAT_VER_3_2			0x32
82 #define	IOAT_VER_3_3			0x33
83 
84 /*
85  * Hardware capabilities.  Different hardware revisions support different
86  * features.  It is often useful to detect specific features than try to infer
87  * them from hardware version.
88  *
89  * Different channels may support different features too; for example, 'PQ' may
90  * only be supported on the first two channels of some hardware.
91  */
92 #define	IOAT_DMACAP_PB			(1 << 0)
93 #define	IOAT_DMACAP_CRC			(1 << 1)
94 #define	IOAT_DMACAP_MARKER_SKIP		(1 << 2)
95 #define	IOAT_DMACAP_OLD_XOR		(1 << 3)
96 #define	IOAT_DMACAP_DCA			(1 << 4)
97 #define	IOAT_DMACAP_MOVECRC		(1 << 5)
98 #define	IOAT_DMACAP_BFILL		(1 << 6)
99 #define	IOAT_DMACAP_EXT_APIC		(1 << 7)
100 #define	IOAT_DMACAP_XOR			(1 << 8)
101 #define	IOAT_DMACAP_PQ			(1 << 9)
102 #define	IOAT_DMACAP_DMA_DIF		(1 << 10)
103 #define	IOAT_DMACAP_DWBES		(1 << 13)
104 #define	IOAT_DMACAP_RAID16SS		(1 << 17)
105 #define	IOAT_DMACAP_DMAMC		(1 << 18)
106 #define	IOAT_DMACAP_CTOS		(1 << 19)
107 
108 #define	IOAT_DMACAP_STR \
109     "\20\24Completion_Timeout_Support\23DMA_with_Multicasting_Support" \
110     "\22RAID_Super_descriptors\16Descriptor_Write_Back_Error_Support" \
111     "\13DMA_with_DIF\12PQ\11XOR\10Extended_APIC_ID\07Block_Fill\06Move_CRC" \
112     "\05DCA\04Old_XOR\03Marker_Skipping\02CRC\01Page_Break"
113 
114 typedef void *bus_dmaengine_t;
115 struct bus_dmadesc;
116 typedef void (*bus_dmaengine_callback_t)(void *arg, int error);
117 
118 unsigned ioat_get_nchannels(void);
119 
120 /*
121  * Called first to acquire a reference to the DMA channel
122  *
123  * Flags may be M_WAITOK or M_NOWAIT.
124  */
125 bus_dmaengine_t ioat_get_dmaengine(uint32_t channel_index, int flags);
126 
127 /* Release the DMA channel */
128 void ioat_put_dmaengine(bus_dmaengine_t dmaengine);
129 
130 /* Check the DMA engine's HW version */
131 int ioat_get_hwversion(bus_dmaengine_t dmaengine);
132 size_t ioat_get_max_io_size(bus_dmaengine_t dmaengine);
133 uint32_t ioat_get_capabilities(bus_dmaengine_t dmaengine);
134 
135 /*
136  * Set interrupt coalescing on a DMA channel.
137  *
138  * The argument is in microseconds.  A zero value disables coalescing.  Any
139  * other value delays interrupt generation for N microseconds to provide
140  * opportunity to coalesce multiple operations into a single interrupt.
141  *
142  * Returns an error status, or zero on success.
143  *
144  * - ERANGE if the given value exceeds the delay supported by the hardware.
145  *   (All current hardware supports a maximum of 0x3fff microseconds delay.)
146  * - ENODEV if the hardware does not support interrupt coalescing.
147  */
148 int ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay);
149 
150 /*
151  * Return the maximum supported coalescing period, for use in
152  * ioat_set_interrupt_coalesce().  If the hardware does not support coalescing,
153  * returns zero.
154  */
155 uint16_t ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine);
156 
157 /*
158  * Acquire must be called before issuing an operation to perform. Release is
159  * called after.  Multiple operations can be issued within the context of one
160  * acquire and release
161  */
162 void ioat_acquire(bus_dmaengine_t dmaengine);
163 void ioat_release(bus_dmaengine_t dmaengine);
164 
165 /*
166  * Acquire_reserve can be called to ensure there is room for N descriptors.  If
167  * it succeeds, the next N valid operations will successfully enqueue.
168  *
169  * It may fail with:
170  *   - ENXIO if the channel is in an errored state, or the driver is being
171  *     unloaded
172  *   - EAGAIN if mflags included M_NOWAIT
173  *
174  * On failure, the caller does not hold the dmaengine.
175  */
176 int ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags);
177 
178 /*
179  * Issue a blockfill operation.  The 64-bit pattern 'fillpattern' is written to
180  * 'len' physically contiguous bytes at 'dst'.
181  *
182  * Only supported on devices with the BFILL capability.
183  */
184 struct bus_dmadesc *ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst,
185     uint64_t fillpattern, bus_size_t len, bus_dmaengine_callback_t callback_fn,
186     void *callback_arg, uint32_t flags);
187 
188 /* Issues the copy data operation */
189 struct bus_dmadesc *ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
190     bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
191     void *callback_arg, uint32_t flags);
192 
193 /*
194  * Issue a copy data operation, with constraints:
195  *  - src1, src2, dst1, dst2 are all page-aligned addresses
196  *  - The quantity to copy is exactly 2 pages;
197  *  - src1 -> dst1, src2 -> dst2
198  *
199  * Why use this instead of normal _copy()?  You can copy two non-contiguous
200  * pages (src, dst, or both) with one descriptor.
201  */
202 struct bus_dmadesc *ioat_copy_8k_aligned(bus_dmaengine_t dmaengine,
203     bus_addr_t dst1, bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
204     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
205 
206 /*
207  * Copy len bytes from dst to src, like ioat_copy().
208  *
209  * Additionally, accumulate a CRC32C of the data.
210  *
211  * If initialseed is not NULL, the value it points to is used to seed the
212  * initial value of the CRC32C.
213  *
214  * If flags include DMA_CRC_STORE and not DMA_CRC_INLINE, crcptr is written
215  * with the 32-bit CRC32C result (in wire format).
216  *
217  * If flags include DMA_CRC_TEST and not DMA_CRC_INLINE, the computed CRC32C is
218  * compared with the 32-bit CRC32C pointed to by crcptr.  If they do not match,
219  * a channel error is raised.
220  *
221  * If the DMA_CRC_INLINE flag is set, crcptr is ignored and the DMA engine uses
222  * the 4 bytes trailing the source data (TEST) or the destination data (STORE).
223  */
224 struct bus_dmadesc *ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst,
225     bus_addr_t src, bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
226     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
227 
228 /*
229  * ioat_crc() is nearly identical to ioat_copy_crc(), but does not actually
230  * move data around.
231  *
232  * Like ioat_copy_crc, ioat_crc computes a CRC32C over len bytes pointed to by
233  * src.  The flags affect its operation in the same way, with one exception:
234  *
235  * If flags includes both DMA_CRC_STORE and DMA_CRC_INLINE, the computed CRC32C
236  * is written to the 4 bytes trailing the *source* data.
237  */
238 struct bus_dmadesc *ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src,
239     bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
240     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
241 
242 /*
243  * Issues a null operation. This issues the operation to the hardware, but the
244  * hardware doesn't do anything with it.
245  */
246 struct bus_dmadesc *ioat_null(bus_dmaengine_t dmaengine,
247     bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
248 
249 
250 #endif /* __IOAT_H__ */
251 
252